1 /*
2 * Copyright (c) 1994, 2024, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package java.lang;
27
28 import java.lang.annotation.Annotation;
29 import java.lang.constant.ClassDesc;
30 import java.lang.constant.ConstantDescs;
31 import java.lang.invoke.TypeDescriptor;
32 import java.lang.invoke.MethodHandles;
33 import java.lang.module.ModuleReader;
34 import java.io.IOException;
35 import java.io.InputStream;
36 import java.io.ObjectStreamField;
37 import java.lang.reflect.AnnotatedElement;
38 import java.lang.reflect.AnnotatedType;
39 import java.lang.reflect.AccessFlag;
40 import java.lang.reflect.Array;
41 import java.lang.reflect.Constructor;
42 import java.lang.reflect.Executable;
43 import java.lang.reflect.Field;
44 import java.lang.reflect.GenericArrayType;
45 import java.lang.reflect.GenericDeclaration;
46 import java.lang.reflect.InvocationTargetException;
47 import java.lang.reflect.Member;
48 import java.lang.reflect.Method;
49 import java.lang.reflect.Modifier;
50 import java.lang.reflect.Proxy;
51 import java.lang.reflect.RecordComponent;
52 import java.lang.reflect.Type;
53 import java.lang.reflect.TypeVariable;
54 import java.lang.constant.Constable;
55 import java.net.URL;
56 import java.security.AccessController;
57 import java.security.Permissions;
58 import java.security.PrivilegedAction;
59 import java.security.ProtectionDomain;
60 import java.util.ArrayList;
61 import java.util.Arrays;
62 import java.util.Collection;
63 import java.util.HashMap;
64 import java.util.HashSet;
65 import java.util.LinkedHashMap;
66 import java.util.LinkedHashSet;
67 import java.util.List;
68 import java.util.Map;
69 import java.util.Objects;
70 import java.util.Optional;
71 import java.util.Set;
72 import java.util.stream.Collectors;
73
74 import jdk.internal.constant.ConstantUtils;
75 import jdk.internal.javac.PreviewFeature;
76 import jdk.internal.loader.BootLoader;
77 import jdk.internal.loader.BuiltinClassLoader;
78 import jdk.internal.misc.PreviewFeatures;
79 import jdk.internal.misc.Unsafe;
80 import jdk.internal.module.Resources;
81 import jdk.internal.reflect.CallerSensitive;
82 import jdk.internal.reflect.CallerSensitiveAdapter;
83 import jdk.internal.reflect.ConstantPool;
84 import jdk.internal.reflect.Reflection;
85 import jdk.internal.reflect.ReflectionFactory;
86 import jdk.internal.vm.annotation.ForceInline;
87 import jdk.internal.vm.annotation.IntrinsicCandidate;
88 import jdk.internal.vm.annotation.Stable;
89
90 import sun.invoke.util.Wrapper;
91 import sun.reflect.generics.factory.CoreReflectionFactory;
92 import sun.reflect.generics.factory.GenericsFactory;
93 import sun.reflect.generics.repository.ClassRepository;
94 import sun.reflect.generics.repository.MethodRepository;
95 import sun.reflect.generics.repository.ConstructorRepository;
96 import sun.reflect.generics.scope.ClassScope;
97 import sun.security.util.SecurityConstants;
98 import sun.reflect.annotation.*;
99 import sun.reflect.misc.ReflectUtil;
100
101 /**
102 * Instances of the class {@code Class} represent classes and
103 * interfaces in a running Java application. An enum class and a record
104 * class are kinds of class; an annotation interface is a kind of
105 * interface. Every array also belongs to a class that is reflected as
106 * a {@code Class} object that is shared by all arrays with the same
107 * element type and number of dimensions. The primitive Java types
108 * ({@code boolean}, {@code byte}, {@code char}, {@code short}, {@code
109 * int}, {@code long}, {@code float}, and {@code double}), and the
110 * keyword {@code void} are also represented as {@code Class} objects.
111 *
112 * <p> {@code Class} has no public constructor. Instead a {@code Class}
113 * object is constructed automatically by the Java Virtual Machine when
114 * a class is derived from the bytes of a {@code class} file through
115 * the invocation of one of the following methods:
116 * <ul>
117 * <li> {@link ClassLoader#defineClass(String, byte[], int, int) ClassLoader::defineClass}
118 * <li> {@link java.lang.invoke.MethodHandles.Lookup#defineClass(byte[])
119 * java.lang.invoke.MethodHandles.Lookup::defineClass}
120 * <li> {@link java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
121 * java.lang.invoke.MethodHandles.Lookup::defineHiddenClass}
122 * </ul>
123 *
124 * <p> The methods of class {@code Class} expose many characteristics of a
125 * class or interface. Most characteristics are derived from the {@code class}
126 * file that the class loader passed to the Java Virtual Machine or
127 * from the {@code class} file passed to {@code Lookup::defineClass}
128 * or {@code Lookup::defineHiddenClass}.
129 * A few characteristics are determined by the class loading environment
130 * at run time, such as the module returned by {@link #getModule() getModule()}.
131 *
132 * <p> The following example uses a {@code Class} object to print the
133 * class name of an object:
134 *
135 * {@snippet lang="java" :
136 * void printClassName(Object obj) {
137 * System.out.println("The class of " + obj +
138 * " is " + obj.getClass().getName());
139 * }}
140 *
141 * It is also possible to get the {@code Class} object for a named
142 * class or interface (or for {@code void}) using a <dfn>class literal</dfn>
143 * (JLS {@jls 15.8.2}).
144 * For example:
145 *
146 * {@snippet lang="java" :
147 * System.out.println("The name of class Foo is: " + Foo.class.getName()); // @highlight substring="Foo.class"
148 * }
149 *
150 * <p> Some methods of class {@code Class} expose whether the declaration of
151 * a class or interface in Java source code was <em>enclosed</em> within
152 * another declaration. Other methods describe how a class or interface
153 * is situated in a <dfn>{@index "nest"}</dfn>. A <a id="nest">nest</a> is a set of
154 * classes and interfaces, in the same run-time package, that
155 * allow mutual access to their {@code private} members.
156 * The classes and interfaces are known as <dfn>{@index "nestmates"}</dfn>
157 * (JVMS {@jvms 4.7.29}).
158 * One nestmate acts as the
159 * <dfn>nest host</dfn> (JVMS {@jvms 4.7.28}), and enumerates the other nestmates which
160 * belong to the nest; each of them in turn records it as the nest host.
161 * The classes and interfaces which belong to a nest, including its host, are
162 * determined when
163 * {@code class} files are generated, for example, a Java compiler
164 * will typically record a top-level class as the host of a nest where the
165 * other members are the classes and interfaces whose declarations are
166 * enclosed within the top-level class declaration.
167 *
168 * <h2><a id=hiddenClasses>Hidden Classes</a></h2>
169 * A class or interface created by the invocation of
170 * {@link java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
171 * Lookup::defineHiddenClass} is a {@linkplain Class#isHidden() <dfn>hidden</dfn>}
172 * class or interface.
173 * All kinds of class, including enum classes and record classes, may be
174 * hidden classes; all kinds of interface, including annotation interfaces,
175 * may be hidden interfaces.
176 *
177 * The {@linkplain #getName() name of a hidden class or interface} is
178 * not a {@linkplain ClassLoader##binary-name binary name},
179 * which means the following:
180 * <ul>
181 * <li>A hidden class or interface cannot be referenced by the constant pools
182 * of other classes and interfaces.
183 * <li>A hidden class or interface cannot be described in
184 * {@linkplain java.lang.constant.ConstantDesc <em>nominal form</em>} by
185 * {@link #describeConstable() Class::describeConstable},
186 * {@link ClassDesc#of(String) ClassDesc::of}, or
187 * {@link ClassDesc#ofDescriptor(String) ClassDesc::ofDescriptor}.
188 * <li>A hidden class or interface cannot be discovered by {@link #forName Class::forName}
189 * or {@link ClassLoader#loadClass(String, boolean) ClassLoader::loadClass}.
190 * </ul>
191 *
192 * A hidden class or interface is never an array class, but may be
193 * the element type of an array. In all other respects, the fact that
194 * a class or interface is hidden has no bearing on the characteristics
195 * exposed by the methods of class {@code Class}.
196 *
197 * <h2><a id=implicitClasses>Implicitly Declared Classes</a></h2>
198 *
199 * Conventionally, a Java compiler, starting from a source file for an
200 * implicitly declared class, say {@code HelloWorld.java}, creates a
201 * similarly-named {@code class} file, {@code HelloWorld.class}, where
202 * the class stored in that {@code class} file is named {@code
203 * "HelloWorld"}, matching the base names of the source and {@code
204 * class} files.
205 *
206 * For the {@code Class} object of an implicitly declared class {@code
207 * HelloWorld}, the methods to get the {@linkplain #getName name} and
208 * {@linkplain #getTypeName type name} return results
209 * equal to {@code "HelloWorld"}. The {@linkplain #getSimpleName
210 * simple name} of such an implicitly declared class is {@code "HelloWorld"} and
211 * the {@linkplain #getCanonicalName canonical name} is {@code "HelloWorld"}.
212 *
213 * @param <T> the type of the class modeled by this {@code Class}
214 * object. For example, the type of {@code String.class} is {@code
215 * Class<String>}. Use {@code Class<?>} if the class being modeled is
216 * unknown.
217 *
218 * @see java.lang.ClassLoader#defineClass(byte[], int, int)
219 * @since 1.0
220 */
221 public final class Class<T> implements java.io.Serializable,
222 GenericDeclaration,
223 Type,
224 AnnotatedElement,
225 TypeDescriptor.OfField<Class<?>>,
226 Constable {
227 private static final int ANNOTATION= 0x00002000;
228 private static final int ENUM = 0x00004000;
229 private static final int SYNTHETIC = 0x00001000;
230
231 private static native void registerNatives();
232 static {
233 registerNatives();
234 }
235
236 /*
237 * Private constructor. Only the Java Virtual Machine creates Class objects.
238 * This constructor is not used and prevents the default constructor being
239 * generated.
240 */
241 private Class(ClassLoader loader, Class<?> arrayComponentType) {
242 // Initialize final field for classLoader. The initialization value of non-null
243 // prevents future JIT optimizations from assuming this final field is null.
244 classLoader = loader;
245 componentType = arrayComponentType;
246 }
247
248 /**
249 * Converts the object to a string. The string representation is the
250 * string "class" or "interface", followed by a space, and then by the
251 * name of the class in the format returned by {@code getName}.
252 * If this {@code Class} object represents a primitive type,
253 * this method returns the name of the primitive type. If
254 * this {@code Class} object represents void this method returns
255 * "void". If this {@code Class} object represents an array type,
256 * this method returns "class " followed by {@code getName}.
257 *
258 * @return a string representation of this {@code Class} object.
259 */
260 public String toString() {
261 String kind = isInterface() ? "interface " : isPrimitive() ? "" : "class ";
262 return kind.concat(getName());
263 }
264
265 /**
266 * Returns a string describing this {@code Class}, including
267 * information about modifiers, {@link #isSealed() sealed}/{@code
268 * non-sealed} status, and type parameters.
269 *
270 * The string is formatted as a list of type modifiers, if any,
271 * followed by the kind of type (empty string for primitive types
272 * and {@code class}, {@code enum}, {@code interface},
273 * {@code @interface}, or {@code record} as appropriate), followed
274 * by the type's name, followed by an angle-bracketed
275 * comma-separated list of the type's type parameters, if any,
276 * including informative bounds on the type parameters, if any.
277 *
278 * A space is used to separate modifiers from one another and to
279 * separate any modifiers from the kind of type. The modifiers
280 * occur in canonical order. If there are no type parameters, the
281 * type parameter list is elided.
282 *
283 * For an array type, the string starts with the type name,
284 * followed by an angle-bracketed comma-separated list of the
285 * type's type parameters, if any, followed by a sequence of
286 * {@code []} characters, one set of brackets per dimension of
287 * the array.
288 *
289 * <p>Note that since information about the runtime representation
290 * of a type is being generated, modifiers not present on the
291 * originating source code or illegal on the originating source
292 * code may be present.
293 *
294 * @return a string describing this {@code Class}, including
295 * information about modifiers and type parameters
296 *
297 * @since 1.8
298 */
299 public String toGenericString() {
300 if (isPrimitive()) {
301 return toString();
302 } else {
303 StringBuilder sb = new StringBuilder();
304 Class<?> component = this;
305 int arrayDepth = 0;
306
307 if (isArray()) {
308 do {
309 arrayDepth++;
310 component = component.getComponentType();
311 } while (component.isArray());
312 sb.append(component.getName());
313 } else {
314 // Class modifiers are a superset of interface modifiers
315 int modifiers = getModifiers() & Modifier.classModifiers();
316 if (modifiers != 0) {
317 sb.append(Modifier.toString(modifiers));
318 sb.append(' ');
319 }
320
321 // A class cannot be strictfp and sealed/non-sealed so
322 // it is sufficient to check for sealed-ness after all
323 // modifiers are printed.
324 addSealingInfo(modifiers, sb);
325
326 if (isAnnotation()) {
327 sb.append('@');
328 }
329 if (isInterface()) { // Note: all annotation interfaces are interfaces
330 sb.append("interface");
331 } else {
332 if (isEnum())
333 sb.append("enum");
334 else if (isRecord())
335 sb.append("record");
336 else
337 sb.append("class");
338 }
339 sb.append(' ');
340 sb.append(getName());
341 }
342
343 TypeVariable<?>[] typeparms = component.getTypeParameters();
344 if (typeparms.length > 0) {
345 sb.append(Arrays.stream(typeparms)
346 .map(Class::typeVarBounds)
347 .collect(Collectors.joining(",", "<", ">")));
348 }
349
350 if (arrayDepth > 0) sb.append("[]".repeat(arrayDepth));
351
352 return sb.toString();
353 }
354 }
355
356 private void addSealingInfo(int modifiers, StringBuilder sb) {
357 // A class can be final XOR sealed XOR non-sealed.
358 if (Modifier.isFinal(modifiers)) {
359 return; // no-op
360 } else {
361 if (isSealed()) {
362 sb.append("sealed ");
363 return;
364 } else {
365 // Check for sealed ancestor, which implies this class
366 // is non-sealed.
367 if (hasSealedAncestor(this)) {
368 sb.append("non-sealed ");
369 }
370 }
371 }
372 }
373
374 private boolean hasSealedAncestor(Class<?> clazz) {
375 // From JLS 8.1.1.2:
376 // "It is a compile-time error if a class has a sealed direct
377 // superclass or a sealed direct superinterface, and is not
378 // declared final, sealed, or non-sealed either explicitly or
379 // implicitly.
380 // Thus, an effect of the sealed keyword is to force all
381 // direct subclasses to explicitly declare whether they are
382 // final, sealed, or non-sealed. This avoids accidentally
383 // exposing a sealed class hierarchy to unwanted subclassing."
384
385 // Therefore, will just check direct superclass and
386 // superinterfaces.
387 var superclass = clazz.getSuperclass();
388 if (superclass != null && superclass.isSealed()) {
389 return true;
390 }
391 for (var superinterface : clazz.getInterfaces()) {
392 if (superinterface.isSealed()) {
393 return true;
394 }
395 }
396 return false;
397 }
398
399 static String typeVarBounds(TypeVariable<?> typeVar) {
400 Type[] bounds = typeVar.getBounds();
401 if (bounds.length == 1 && bounds[0].equals(Object.class)) {
402 return typeVar.getName();
403 } else {
404 return typeVar.getName() + " extends " +
405 Arrays.stream(bounds)
406 .map(Type::getTypeName)
407 .collect(Collectors.joining(" & "));
408 }
409 }
410
411 /**
412 * Returns the {@code Class} object associated with the class or
413 * interface with the given string name. Invoking this method is
414 * equivalent to:
415 *
416 * {@snippet lang="java" :
417 * Class.forName(className, true, currentLoader)
418 * }
419 *
420 * where {@code currentLoader} denotes the defining class loader of
421 * the current class.
422 *
423 * <p> For example, the following code fragment returns the
424 * runtime {@code Class} object for the class named
425 * {@code java.lang.Thread}:
426 *
427 * {@snippet lang="java" :
428 * Class<?> t = Class.forName("java.lang.Thread");
429 * }
430 * <p>
431 * A call to {@code forName("X")} causes the class named
432 * {@code X} to be initialized.
433 *
434 * <p>
435 * In cases where this method is called from a context where there is no
436 * caller frame on the stack (e.g. when called directly from a JNI
437 * attached thread), the system class loader is used.
438 *
439 * @param className the {@linkplain ClassLoader##binary-name binary name}
440 * of the class or the string representing an array type
441 * @return the {@code Class} object for the class with the
442 * specified name.
443 * @throws LinkageError if the linkage fails
444 * @throws ExceptionInInitializerError if the initialization provoked
445 * by this method fails
446 * @throws ClassNotFoundException if the class cannot be located
447 *
448 * @jls 12.2 Loading of Classes and Interfaces
449 * @jls 12.3 Linking of Classes and Interfaces
450 * @jls 12.4 Initialization of Classes and Interfaces
451 */
452 @CallerSensitive
453 public static Class<?> forName(String className)
454 throws ClassNotFoundException {
455 Class<?> caller = Reflection.getCallerClass();
456 return forName(className, caller);
457 }
458
459 // Caller-sensitive adapter method for reflective invocation
460 @CallerSensitiveAdapter
461 private static Class<?> forName(String className, Class<?> caller)
462 throws ClassNotFoundException {
463 ClassLoader loader = (caller == null) ? ClassLoader.getSystemClassLoader()
464 : ClassLoader.getClassLoader(caller);
465 if (loader instanceof BuiltinClassLoader bcl) {
466 if (bcl.usePositiveCache) {
467 Class<?> result = bcl.checkPositiveLookupCache(className);
468 if (result != null) {
469 return result;
470 }
471 }
472 if (bcl.useNegativeCache && bcl.checkNegativeLookupCache(className)) {
473 throw new ClassNotFoundException(className);
474 }
475 }
476 return forName0(className, true, loader, caller);
477 }
478
479 /**
480 * Returns the {@code Class} object associated with the class or
481 * interface with the given string name, using the given class loader.
482 * Given the {@linkplain ClassLoader##binary-name binary name} for a class or interface,
483 * this method attempts to locate and load the class or interface. The specified
484 * class loader is used to load the class or interface. If the parameter
485 * {@code loader} is {@code null}, the class is loaded through the bootstrap
486 * class loader. The class is initialized only if the
487 * {@code initialize} parameter is {@code true} and if it has
488 * not been initialized earlier.
489 *
490 * <p> This method cannot be used to obtain any of the {@code Class} objects
491 * representing primitive types or void, hidden classes or interfaces,
492 * or array classes whose element type is a hidden class or interface.
493 * If {@code name} denotes a primitive type or void, for example {@code I},
494 * an attempt will be made to locate a user-defined class in the unnamed package
495 * whose name is {@code I} instead.
496 * To obtain a {@code Class} object for a named primitive type
497 * such as {@code int} or {@code long} use {@link
498 * #forPrimitiveName(String)}.
499 *
500 * <p> To obtain the {@code Class} object associated with an array class,
501 * the name consists of one or more {@code '['} representing the depth
502 * of the array nesting, followed by the element type as encoded in
503 * {@linkplain ##nameFormat the table} specified in {@code Class.getName()}.
504 *
505 * <p> Examples:
506 * {@snippet lang="java" :
507 * Class<?> threadClass = Class.forName("java.lang.Thread", false, currentLoader);
508 * Class<?> stringArrayClass = Class.forName("[Ljava.lang.String;", false, currentLoader);
509 * Class<?> intArrayClass = Class.forName("[[[I", false, currentLoader); // Class of int[][][]
510 * Class<?> nestedClass = Class.forName("java.lang.Character$UnicodeBlock", false, currentLoader);
511 * Class<?> fooClass = Class.forName("Foo", true, currentLoader);
512 * }
513 *
514 * <p> A call to {@code getName()} on the {@code Class} object returned
515 * from {@code forName(}<i>N</i>{@code )} returns <i>N</i>.
516 *
517 * <p> A call to {@code forName("[L}<i>N</i>{@code ;")} causes the element type
518 * named <i>N</i> to be loaded but not initialized regardless of the value
519 * of the {@code initialize} parameter.
520 *
521 * @apiNote
522 * This method throws errors related to loading, linking or initializing
523 * as specified in Sections {@jls 12.2}, {@jls 12.3}, and {@jls 12.4} of
524 * <cite>The Java Language Specification</cite>.
525 * In addition, this method does not check whether the requested class
526 * is accessible to its caller.
527 *
528 * @param name the {@linkplain ClassLoader##binary-name binary name}
529 * of the class or the string representing an array class
530 *
531 * @param initialize if {@code true} the class will be initialized
532 * (which implies linking). See Section {@jls
533 * 12.4} of <cite>The Java Language
534 * Specification</cite>.
535 * @param loader class loader from which the class must be loaded
536 * @return class object representing the desired class
537 *
538 * @throws LinkageError if the linkage fails
539 * @throws ExceptionInInitializerError if the initialization provoked
540 * by this method fails
541 * @throws ClassNotFoundException if the class cannot be located by
542 * the specified class loader
543 * @throws SecurityException
544 * if a security manager is present, and the {@code loader} is
545 * {@code null}, and the caller's class loader is not
546 * {@code null}, and the caller does not have the
547 * {@link RuntimePermission}{@code ("getClassLoader")}
548 *
549 * @see java.lang.Class#forName(String)
550 * @see java.lang.ClassLoader
551 *
552 * @jls 12.2 Loading of Classes and Interfaces
553 * @jls 12.3 Linking of Classes and Interfaces
554 * @jls 12.4 Initialization of Classes and Interfaces
555 * @jls 13.1 The Form of a Binary
556 * @since 1.2
557 */
558 @CallerSensitive
559 public static Class<?> forName(String name, boolean initialize,
560 ClassLoader loader)
561 throws ClassNotFoundException
562 {
563 Class<?> caller = null;
564 @SuppressWarnings("removal")
565 SecurityManager sm = System.getSecurityManager();
566 if (sm != null) {
567 // Reflective call to get caller class is only needed if a security manager
568 // is present. Avoid the overhead of making this call otherwise.
569 caller = Reflection.getCallerClass();
570 }
571 return forName(name, initialize, loader, caller);
572 }
573
574 // Caller-sensitive adapter method for reflective invocation
575 @CallerSensitiveAdapter
576 private static Class<?> forName(String name, boolean initialize, ClassLoader loader, Class<?> caller)
577 throws ClassNotFoundException
578 {
579 @SuppressWarnings("removal")
580 SecurityManager sm = System.getSecurityManager();
581 if (sm != null) {
582 // Reflective call to get caller class is only needed if a security manager
583 // is present. Avoid the overhead of making this call otherwise.
584 if (loader == null) {
585 ClassLoader ccl = ClassLoader.getClassLoader(caller);
586 if (ccl != null) {
587 sm.checkPermission(
588 SecurityConstants.GET_CLASSLOADER_PERMISSION);
589 }
590 }
591 }
592 if (loader instanceof BuiltinClassLoader bcl) {
593 if (bcl.usePositiveCache) {
594 Class<?> result = bcl.checkPositiveLookupCache(name);
595 if (result != null) {
596 return result;
597 }
598 }
599 if (bcl.useNegativeCache && bcl.checkNegativeLookupCache(name)) {
600 throw new ClassNotFoundException(name);
601 }
602 }
603 return forName0(name, initialize, loader, caller);
604 }
605
606 /** Called after security check for system loader access checks have been made. */
607 private static native Class<?> forName0(String name, boolean initialize,
608 ClassLoader loader,
609 Class<?> caller)
610 throws ClassNotFoundException;
611
612
613 /**
614 * Returns the {@code Class} with the given {@linkplain ClassLoader##binary-name
615 * binary name} in the given module.
616 *
617 * <p> This method attempts to locate and load the class or interface.
618 * It does not link the class, and does not run the class initializer.
619 * If the class is not found, this method returns {@code null}. </p>
620 *
621 * <p> If the class loader of the given module defines other modules and
622 * the given name is a class defined in a different module, this method
623 * returns {@code null} after the class is loaded. </p>
624 *
625 * <p> This method does not check whether the requested class is
626 * accessible to its caller. </p>
627 *
628 * @apiNote
629 * This method does not support loading of array types, unlike
630 * {@link #forName(String, boolean, ClassLoader)}. The class name must be
631 * a binary name. This method returns {@code null} on failure rather than
632 * throwing a {@link ClassNotFoundException}, as is done by
633 * the {@link #forName(String, boolean, ClassLoader)} method.
634 * The security check is a stack-based permission check if the caller
635 * loads a class in another module.
636 *
637 * @param module A module
638 * @param name The {@linkplain ClassLoader##binary-name binary name}
639 * of the class
640 * @return {@code Class} object of the given name defined in the given module;
641 * {@code null} if not found.
642 *
643 * @throws NullPointerException if the given module or name is {@code null}
644 *
645 * @throws LinkageError if the linkage fails
646 *
647 * @throws SecurityException
648 * <ul>
649 * <li> if the caller is not the specified module and
650 * {@code RuntimePermission("getClassLoader")} permission is denied; or</li>
651 * <li> access to the module content is denied. For example,
652 * permission check will be performed when a class loader calls
653 * {@link ModuleReader#open(String)} to read the bytes of a class file
654 * in a module.</li>
655 * </ul>
656 *
657 * @jls 12.2 Loading of Classes and Interfaces
658 * @jls 12.3 Linking of Classes and Interfaces
659 * @since 9
660 */
661 @SuppressWarnings("removal")
662 @CallerSensitive
663 public static Class<?> forName(Module module, String name) {
664 Class<?> caller = null;
665 SecurityManager sm = System.getSecurityManager();
666 if (sm != null) {
667 caller = Reflection.getCallerClass();
668 }
669 return forName(module, name, caller);
670 }
671
672 // Caller-sensitive adapter method for reflective invocation
673 @SuppressWarnings("removal")
674 @CallerSensitiveAdapter
675 private static Class<?> forName(Module module, String name, Class<?> caller) {
676 Objects.requireNonNull(module);
677 Objects.requireNonNull(name);
678
679 ClassLoader cl;
680 SecurityManager sm = System.getSecurityManager();
681 if (sm != null) {
682 if (caller != null && caller.getModule() != module) {
683 // if caller is null, Class.forName is the last java frame on the stack.
684 // java.base has all permissions
685 sm.checkPermission(SecurityConstants.GET_CLASSLOADER_PERMISSION);
686 }
687 PrivilegedAction<ClassLoader> pa = module::getClassLoader;
688 cl = AccessController.doPrivileged(pa);
689 } else {
690 cl = module.getClassLoader();
691 }
692
693 if (cl != null) {
694 return cl.loadClass(module, name);
695 } else {
696 return BootLoader.loadClass(module, name);
697 }
698 }
699
700 /**
701 * {@return the {@code Class} object associated with the
702 * {@linkplain #isPrimitive() primitive type} of the given name}
703 * If the argument is not the name of a primitive type, {@code
704 * null} is returned.
705 *
706 * @param primitiveName the name of the primitive type to find
707 *
708 * @throws NullPointerException if the argument is {@code null}
709 *
710 * @jls 4.2 Primitive Types and Values
711 * @jls 15.8.2 Class Literals
712 * @since 22
713 */
714 public static Class<?> forPrimitiveName(String primitiveName) {
715 return switch(primitiveName) {
716 // Integral types
717 case "int" -> int.class;
718 case "long" -> long.class;
719 case "short" -> short.class;
720 case "char" -> char.class;
721 case "byte" -> byte.class;
722
723 // Floating-point types
724 case "float" -> float.class;
725 case "double" -> double.class;
726
727 // Other types
728 case "boolean" -> boolean.class;
729 case "void" -> void.class;
730
731 default -> null;
732 };
733 }
734
735 /**
736 * Creates a new instance of the class represented by this {@code Class}
737 * object. The class is instantiated as if by a {@code new}
738 * expression with an empty argument list. The class is initialized if it
739 * has not already been initialized.
740 *
741 * @deprecated This method propagates any exception thrown by the
742 * nullary constructor, including a checked exception. Use of
743 * this method effectively bypasses the compile-time exception
744 * checking that would otherwise be performed by the compiler.
745 * The {@link
746 * java.lang.reflect.Constructor#newInstance(java.lang.Object...)
747 * Constructor.newInstance} method avoids this problem by wrapping
748 * any exception thrown by the constructor in a (checked) {@link
749 * java.lang.reflect.InvocationTargetException}.
750 *
751 * <p>The call
752 *
753 * {@snippet lang="java" :
754 * clazz.newInstance()
755 * }
756 *
757 * can be replaced by
758 *
759 * {@snippet lang="java" :
760 * clazz.getDeclaredConstructor().newInstance()
761 * }
762 *
763 * The latter sequence of calls is inferred to be able to throw
764 * the additional exception types {@link
765 * InvocationTargetException} and {@link
766 * NoSuchMethodException}. Both of these exception types are
767 * subclasses of {@link ReflectiveOperationException}.
768 *
769 * @return a newly allocated instance of the class represented by this
770 * object.
771 * @throws IllegalAccessException if the class or its nullary
772 * constructor is not accessible.
773 * @throws InstantiationException
774 * if this {@code Class} represents an abstract class,
775 * an interface, an array class, a primitive type, or void;
776 * or if the class has no nullary constructor;
777 * or if the instantiation fails for some other reason.
778 * @throws ExceptionInInitializerError if the initialization
779 * provoked by this method fails.
780 * @throws SecurityException
781 * If a security manager, <i>s</i>, is present and
782 * the caller's class loader is not the same as or an
783 * ancestor of the class loader for the current class and
784 * invocation of {@link SecurityManager#checkPackageAccess
785 * s.checkPackageAccess()} denies access to the package
786 * of this class.
787 */
788 @SuppressWarnings("removal")
789 @CallerSensitive
790 @Deprecated(since="9")
791 public T newInstance()
792 throws InstantiationException, IllegalAccessException
793 {
794 SecurityManager sm = System.getSecurityManager();
795 if (sm != null) {
796 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), false);
797 }
798
799 // Constructor lookup
800 Constructor<T> tmpConstructor = cachedConstructor;
801 if (tmpConstructor == null) {
802 if (this == Class.class) {
803 throw new IllegalAccessException(
804 "Can not call newInstance() on the Class for java.lang.Class"
805 );
806 }
807 try {
808 Class<?>[] empty = {};
809 final Constructor<T> c = getReflectionFactory().copyConstructor(
810 getConstructor0(empty, Member.DECLARED));
811 // Disable accessibility checks on the constructor
812 // access check is done with the true caller
813 java.security.AccessController.doPrivileged(
814 new java.security.PrivilegedAction<>() {
815 public Void run() {
816 c.setAccessible(true);
817 return null;
818 }
819 });
820 cachedConstructor = tmpConstructor = c;
821 } catch (NoSuchMethodException e) {
822 throw (InstantiationException)
823 new InstantiationException(getName()).initCause(e);
824 }
825 }
826
827 try {
828 Class<?> caller = Reflection.getCallerClass();
829 return getReflectionFactory().newInstance(tmpConstructor, null, caller);
830 } catch (InvocationTargetException e) {
831 Unsafe.getUnsafe().throwException(e.getTargetException());
832 // Not reached
833 return null;
834 }
835 }
836
837 private transient volatile Constructor<T> cachedConstructor;
838
839 /**
840 * Determines if the specified {@code Object} is assignment-compatible
841 * with the object represented by this {@code Class}. This method is
842 * the dynamic equivalent of the Java language {@code instanceof}
843 * operator. The method returns {@code true} if the specified
844 * {@code Object} argument is non-null and can be cast to the
845 * reference type represented by this {@code Class} object without
846 * raising a {@code ClassCastException.} It returns {@code false}
847 * otherwise.
848 *
849 * <p> Specifically, if this {@code Class} object represents a
850 * declared class, this method returns {@code true} if the specified
851 * {@code Object} argument is an instance of the represented class (or
852 * of any of its subclasses); it returns {@code false} otherwise. If
853 * this {@code Class} object represents an array class, this method
854 * returns {@code true} if the specified {@code Object} argument
855 * can be converted to an object of the array class by an identity
856 * conversion or by a widening reference conversion; it returns
857 * {@code false} otherwise. If this {@code Class} object
858 * represents an interface, this method returns {@code true} if the
859 * class or any superclass of the specified {@code Object} argument
860 * implements this interface; it returns {@code false} otherwise. If
861 * this {@code Class} object represents a primitive type, this method
862 * returns {@code false}.
863 *
864 * @param obj the object to check
865 * @return true if {@code obj} is an instance of this class
866 *
867 * @since 1.1
868 */
869 @IntrinsicCandidate
870 public native boolean isInstance(Object obj);
871
872
873 /**
874 * Determines if the class or interface represented by this
875 * {@code Class} object is either the same as, or is a superclass or
876 * superinterface of, the class or interface represented by the specified
877 * {@code Class} parameter. It returns {@code true} if so;
878 * otherwise it returns {@code false}. If this {@code Class}
879 * object represents a primitive type, this method returns
880 * {@code true} if the specified {@code Class} parameter is
881 * exactly this {@code Class} object; otherwise it returns
882 * {@code false}.
883 *
884 * <p> Specifically, this method tests whether the type represented by the
885 * specified {@code Class} parameter can be converted to the type
886 * represented by this {@code Class} object via an identity conversion
887 * or via a widening reference conversion. See <cite>The Java Language
888 * Specification</cite>, sections {@jls 5.1.1} and {@jls 5.1.4},
889 * for details.
890 *
891 * @param cls the {@code Class} object to be checked
892 * @return the {@code boolean} value indicating whether objects of the
893 * type {@code cls} can be assigned to objects of this class
894 * @throws NullPointerException if the specified Class parameter is
895 * null.
896 * @since 1.1
897 */
898 @IntrinsicCandidate
899 public native boolean isAssignableFrom(Class<?> cls);
900
901
902 /**
903 * Determines if this {@code Class} object represents an
904 * interface type.
905 *
906 * @return {@code true} if this {@code Class} object represents an interface;
907 * {@code false} otherwise.
908 */
909 @IntrinsicCandidate
910 public native boolean isInterface();
911
912
913 /**
914 * Determines if this {@code Class} object represents an array class.
915 *
916 * @return {@code true} if this {@code Class} object represents an array class;
917 * {@code false} otherwise.
918 * @since 1.1
919 */
920 @IntrinsicCandidate
921 public native boolean isArray();
922
923
924 /**
925 * Determines if this {@code Class} object represents a primitive
926 * type or void.
927 *
928 * <p> There are nine predefined {@code Class} objects to
929 * represent the eight primitive types and void. These are
930 * created by the Java Virtual Machine, and have the same
931 * {@linkplain #getName() names} as the primitive types that they
932 * represent, namely {@code boolean}, {@code byte}, {@code char},
933 * {@code short}, {@code int}, {@code long}, {@code float}, and
934 * {@code double}.
935 *
936 * <p>No other class objects are considered primitive.
937 *
938 * @apiNote
939 * A {@code Class} object represented by a primitive type can be
940 * accessed via the {@code TYPE} public static final variables
941 * defined in the primitive wrapper classes such as {@link
942 * java.lang.Integer#TYPE Integer.TYPE}. In the Java programming
943 * language, the objects may be referred to by a class literal
944 * expression such as {@code int.class}. The {@code Class} object
945 * for void can be expressed as {@code void.class} or {@link
946 * java.lang.Void#TYPE Void.TYPE}.
947 *
948 * @return true if and only if this class represents a primitive type
949 *
950 * @see java.lang.Boolean#TYPE
951 * @see java.lang.Character#TYPE
952 * @see java.lang.Byte#TYPE
953 * @see java.lang.Short#TYPE
954 * @see java.lang.Integer#TYPE
955 * @see java.lang.Long#TYPE
956 * @see java.lang.Float#TYPE
957 * @see java.lang.Double#TYPE
958 * @see java.lang.Void#TYPE
959 * @since 1.1
960 * @jls 15.8.2 Class Literals
961 */
962 @IntrinsicCandidate
963 public native boolean isPrimitive();
964
965 /**
966 * Returns true if this {@code Class} object represents an annotation
967 * interface. Note that if this method returns true, {@link #isInterface()}
968 * would also return true, as all annotation interfaces are also interfaces.
969 *
970 * @return {@code true} if this {@code Class} object represents an annotation
971 * interface; {@code false} otherwise
972 * @since 1.5
973 */
974 public boolean isAnnotation() {
975 return (getModifiers() & ANNOTATION) != 0;
976 }
977
978 /**
979 *{@return {@code true} if and only if this class has the synthetic modifier
980 * bit set}
981 *
982 * @jls 13.1 The Form of a Binary
983 * @jvms 4.1 The {@code ClassFile} Structure
984 * @see <a
985 * href="{@docRoot}/java.base/java/lang/reflect/package-summary.html#LanguageJvmModel">Java
986 * programming language and JVM modeling in core reflection</a>
987 * @since 1.5
988 */
989 public boolean isSynthetic() {
990 return (getModifiers() & SYNTHETIC) != 0;
991 }
992
993 /**
994 * Returns the name of the entity (class, interface, array class,
995 * primitive type, or void) represented by this {@code Class} object.
996 *
997 * <p> If this {@code Class} object represents a class or interface,
998 * not an array class, then:
999 * <ul>
1000 * <li> If the class or interface is not {@linkplain #isHidden() hidden},
1001 * then the {@linkplain ClassLoader##binary-name binary name}
1002 * of the class or interface is returned.
1003 * <li> If the class or interface is hidden, then the result is a string
1004 * of the form: {@code N + '/' + <suffix>}
1005 * where {@code N} is the {@linkplain ClassLoader##binary-name binary name}
1006 * indicated by the {@code class} file passed to
1007 * {@link java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
1008 * Lookup::defineHiddenClass}, and {@code <suffix>} is an unqualified name.
1009 * </ul>
1010 *
1011 * <p> If this {@code Class} object represents an array class, then
1012 * the result is a string consisting of one or more '{@code [}' characters
1013 * representing the depth of the array nesting, followed by the element
1014 * type as encoded using the following table:
1015 *
1016 * <blockquote><table class="striped" id="nameFormat">
1017 * <caption style="display:none">Element types and encodings</caption>
1018 * <thead>
1019 * <tr><th scope="col"> Element Type <th scope="col"> Encoding
1020 * </thead>
1021 * <tbody style="text-align:left">
1022 * <tr><th scope="row"> {@code boolean} <td style="text-align:center"> {@code Z}
1023 * <tr><th scope="row"> {@code byte} <td style="text-align:center"> {@code B}
1024 * <tr><th scope="row"> {@code char} <td style="text-align:center"> {@code C}
1025 * <tr><th scope="row"> class or interface with {@linkplain ClassLoader##binary-name binary name} <i>N</i>
1026 * <td style="text-align:center"> {@code L}<em>N</em>{@code ;}
1027 * <tr><th scope="row"> {@code double} <td style="text-align:center"> {@code D}
1028 * <tr><th scope="row"> {@code float} <td style="text-align:center"> {@code F}
1029 * <tr><th scope="row"> {@code int} <td style="text-align:center"> {@code I}
1030 * <tr><th scope="row"> {@code long} <td style="text-align:center"> {@code J}
1031 * <tr><th scope="row"> {@code short} <td style="text-align:center"> {@code S}
1032 * </tbody>
1033 * </table></blockquote>
1034 *
1035 * <p> If this {@code Class} object represents a primitive type or {@code void},
1036 * then the result is a string with the same spelling as the Java language
1037 * keyword which corresponds to the primitive type or {@code void}.
1038 *
1039 * <p> Examples:
1040 * <blockquote><pre>
1041 * String.class.getName()
1042 * returns "java.lang.String"
1043 * Character.UnicodeBlock.class.getName()
1044 * returns "java.lang.Character$UnicodeBlock"
1045 * byte.class.getName()
1046 * returns "byte"
1047 * (new Object[3]).getClass().getName()
1048 * returns "[Ljava.lang.Object;"
1049 * (new int[3][4][5][6][7][8][9]).getClass().getName()
1050 * returns "[[[[[[[I"
1051 * </pre></blockquote>
1052 *
1053 * @apiNote
1054 * Distinct class objects can have the same name but different class loaders.
1055 *
1056 * @return the name of the class, interface, or other entity
1057 * represented by this {@code Class} object.
1058 * @jls 13.1 The Form of a Binary
1059 */
1060 public String getName() {
1061 String name = this.name;
1062 return name != null ? name : initClassName();
1063 }
1064
1065 // Cache the name to reduce the number of calls into the VM.
1066 // This field would be set by VM itself during initClassName call.
1067 private transient String name;
1068 private native String initClassName();
1069
1070 /**
1071 * Returns the class loader for the class. Some implementations may use
1072 * null to represent the bootstrap class loader. This method will return
1073 * null in such implementations if this class was loaded by the bootstrap
1074 * class loader.
1075 *
1076 * <p>If this {@code Class} object
1077 * represents a primitive type or void, null is returned.
1078 *
1079 * @return the class loader that loaded the class or interface
1080 * represented by this {@code Class} object.
1081 * @throws SecurityException
1082 * if a security manager is present, and the caller's class loader
1083 * is not {@code null} and is not the same as or an ancestor of the
1084 * class loader for the class whose class loader is requested,
1085 * and the caller does not have the
1086 * {@link RuntimePermission}{@code ("getClassLoader")}
1087 * @see java.lang.ClassLoader
1088 * @see SecurityManager#checkPermission
1089 * @see java.lang.RuntimePermission
1090 */
1091 @CallerSensitive
1092 @ForceInline // to ensure Reflection.getCallerClass optimization
1093 public ClassLoader getClassLoader() {
1094 ClassLoader cl = classLoader;
1095 if (cl == null)
1096 return null;
1097 @SuppressWarnings("removal")
1098 SecurityManager sm = System.getSecurityManager();
1099 if (sm != null) {
1100 ClassLoader.checkClassLoaderPermission(cl, Reflection.getCallerClass());
1101 }
1102 return cl;
1103 }
1104
1105 // Package-private to allow ClassLoader access
1106 ClassLoader getClassLoader0() { return classLoader; }
1107
1108 /**
1109 * Returns the module that this class or interface is a member of.
1110 *
1111 * If this class represents an array type then this method returns the
1112 * {@code Module} for the element type. If this class represents a
1113 * primitive type or void, then the {@code Module} object for the
1114 * {@code java.base} module is returned.
1115 *
1116 * If this class is in an unnamed module then the {@linkplain
1117 * ClassLoader#getUnnamedModule() unnamed} {@code Module} of the class
1118 * loader for this class is returned.
1119 *
1120 * @return the module that this class or interface is a member of
1121 *
1122 * @since 9
1123 */
1124 public Module getModule() {
1125 return module;
1126 }
1127
1128 // set by VM
1129 @Stable
1130 private transient Module module;
1131
1132 // Initialized in JVM not by private constructor
1133 // This field is filtered from reflection access, i.e. getDeclaredField
1134 // will throw NoSuchFieldException
1135 private final ClassLoader classLoader;
1136
1137 private transient Object classData; // Set by VM
1138 private transient Object[] signers; // Read by VM, mutable
1139
1140 // package-private
1141 Object getClassData() {
1142 return classData;
1143 }
1144
1145 /**
1146 * Returns an array of {@code TypeVariable} objects that represent the
1147 * type variables declared by the generic declaration represented by this
1148 * {@code GenericDeclaration} object, in declaration order. Returns an
1149 * array of length 0 if the underlying generic declaration declares no type
1150 * variables.
1151 *
1152 * @return an array of {@code TypeVariable} objects that represent
1153 * the type variables declared by this generic declaration
1154 * @throws java.lang.reflect.GenericSignatureFormatError if the generic
1155 * signature of this generic declaration does not conform to
1156 * the format specified in section {@jvms 4.7.9} of
1157 * <cite>The Java Virtual Machine Specification</cite>
1158 * @since 1.5
1159 */
1160 @SuppressWarnings("unchecked")
1161 public TypeVariable<Class<T>>[] getTypeParameters() {
1162 ClassRepository info = getGenericInfo();
1163 if (info != null)
1164 return (TypeVariable<Class<T>>[])info.getTypeParameters();
1165 else
1166 return (TypeVariable<Class<T>>[])new TypeVariable<?>[0];
1167 }
1168
1169
1170 /**
1171 * Returns the {@code Class} representing the direct superclass of the
1172 * entity (class, interface, primitive type or void) represented by
1173 * this {@code Class}. If this {@code Class} represents either the
1174 * {@code Object} class, an interface, a primitive type, or void, then
1175 * null is returned. If this {@code Class} object represents an array class
1176 * then the {@code Class} object representing the {@code Object} class is
1177 * returned.
1178 *
1179 * @return the direct superclass of the class represented by this {@code Class} object
1180 */
1181 @IntrinsicCandidate
1182 public native Class<? super T> getSuperclass();
1183
1184
1185 /**
1186 * Returns the {@code Type} representing the direct superclass of
1187 * the entity (class, interface, primitive type or void) represented by
1188 * this {@code Class} object.
1189 *
1190 * <p>If the superclass is a parameterized type, the {@code Type}
1191 * object returned must accurately reflect the actual type
1192 * arguments used in the source code. The parameterized type
1193 * representing the superclass is created if it had not been
1194 * created before. See the declaration of {@link
1195 * java.lang.reflect.ParameterizedType ParameterizedType} for the
1196 * semantics of the creation process for parameterized types. If
1197 * this {@code Class} object represents either the {@code Object}
1198 * class, an interface, a primitive type, or void, then null is
1199 * returned. If this {@code Class} object represents an array class
1200 * then the {@code Class} object representing the {@code Object} class is
1201 * returned.
1202 *
1203 * @throws java.lang.reflect.GenericSignatureFormatError if the generic
1204 * class signature does not conform to the format specified in
1205 * section {@jvms 4.7.9} of <cite>The Java Virtual
1206 * Machine Specification</cite>
1207 * @throws TypeNotPresentException if the generic superclass
1208 * refers to a non-existent type declaration
1209 * @throws java.lang.reflect.MalformedParameterizedTypeException if the
1210 * generic superclass refers to a parameterized type that cannot be
1211 * instantiated for any reason
1212 * @return the direct superclass of the class represented by this {@code Class} object
1213 * @since 1.5
1214 */
1215 public Type getGenericSuperclass() {
1216 ClassRepository info = getGenericInfo();
1217 if (info == null) {
1218 return getSuperclass();
1219 }
1220
1221 // Historical irregularity:
1222 // Generic signature marks interfaces with superclass = Object
1223 // but this API returns null for interfaces
1224 if (isInterface()) {
1225 return null;
1226 }
1227
1228 return info.getSuperclass();
1229 }
1230
1231 /**
1232 * Gets the package of this class.
1233 *
1234 * <p>If this class represents an array type, a primitive type or void,
1235 * this method returns {@code null}.
1236 *
1237 * @return the package of this class.
1238 */
1239 public Package getPackage() {
1240 if (isPrimitive() || isArray()) {
1241 return null;
1242 }
1243 ClassLoader cl = classLoader;
1244 return cl != null ? cl.definePackage(this)
1245 : BootLoader.definePackage(this);
1246 }
1247
1248 /**
1249 * Returns the fully qualified package name.
1250 *
1251 * <p> If this class is a top level class, then this method returns the fully
1252 * qualified name of the package that the class is a member of, or the
1253 * empty string if the class is in an unnamed package.
1254 *
1255 * <p> If this class is a member class, then this method is equivalent to
1256 * invoking {@code getPackageName()} on the {@linkplain #getEnclosingClass
1257 * enclosing class}.
1258 *
1259 * <p> If this class is a {@linkplain #isLocalClass local class} or an {@linkplain
1260 * #isAnonymousClass() anonymous class}, then this method is equivalent to
1261 * invoking {@code getPackageName()} on the {@linkplain #getDeclaringClass
1262 * declaring class} of the {@linkplain #getEnclosingMethod enclosing method} or
1263 * {@linkplain #getEnclosingConstructor enclosing constructor}.
1264 *
1265 * <p> If this class represents an array type then this method returns the
1266 * package name of the element type. If this class represents a primitive
1267 * type or void then the package name "{@code java.lang}" is returned.
1268 *
1269 * @return the fully qualified package name
1270 *
1271 * @since 9
1272 * @jls 6.7 Fully Qualified Names and Canonical Names
1273 */
1274 public String getPackageName() {
1275 String pn = this.packageName;
1276 if (pn == null) {
1277 Class<?> c = isArray() ? elementType() : this;
1278 if (c.isPrimitive()) {
1279 pn = "java.lang";
1280 } else {
1281 String cn = c.getName();
1282 int dot = cn.lastIndexOf('.');
1283 pn = (dot != -1) ? cn.substring(0, dot).intern() : "";
1284 }
1285 this.packageName = pn;
1286 }
1287 return pn;
1288 }
1289
1290 // cached package name
1291 private transient String packageName;
1292
1293 /**
1294 * Returns the interfaces directly implemented by the class or interface
1295 * represented by this {@code Class} object.
1296 *
1297 * <p>If this {@code Class} object represents a class, the return value is an array
1298 * containing objects representing all interfaces directly implemented by
1299 * the class. The order of the interface objects in the array corresponds
1300 * to the order of the interface names in the {@code implements} clause of
1301 * the declaration of the class represented by this {@code Class} object. For example,
1302 * given the declaration:
1303 * <blockquote>
1304 * {@code class Shimmer implements FloorWax, DessertTopping { ... }}
1305 * </blockquote>
1306 * suppose the value of {@code s} is an instance of
1307 * {@code Shimmer}; the value of the expression:
1308 * <blockquote>
1309 * {@code s.getClass().getInterfaces()[0]}
1310 * </blockquote>
1311 * is the {@code Class} object that represents interface
1312 * {@code FloorWax}; and the value of:
1313 * <blockquote>
1314 * {@code s.getClass().getInterfaces()[1]}
1315 * </blockquote>
1316 * is the {@code Class} object that represents interface
1317 * {@code DessertTopping}.
1318 *
1319 * <p>If this {@code Class} object represents an interface, the array contains objects
1320 * representing all interfaces directly extended by the interface. The
1321 * order of the interface objects in the array corresponds to the order of
1322 * the interface names in the {@code extends} clause of the declaration of
1323 * the interface represented by this {@code Class} object.
1324 *
1325 * <p>If this {@code Class} object represents a class or interface that implements no
1326 * interfaces, the method returns an array of length 0.
1327 *
1328 * <p>If this {@code Class} object represents a primitive type or void, the method
1329 * returns an array of length 0.
1330 *
1331 * <p>If this {@code Class} object represents an array type, the
1332 * interfaces {@code Cloneable} and {@code java.io.Serializable} are
1333 * returned in that order.
1334 *
1335 * @return an array of interfaces directly implemented by this class
1336 */
1337 public Class<?>[] getInterfaces() {
1338 // defensively copy before handing over to user code
1339 return getInterfaces(true);
1340 }
1341
1342 private Class<?>[] getInterfaces(boolean cloneArray) {
1343 ReflectionData<T> rd = reflectionData();
1344 if (rd == null) {
1345 // no cloning required
1346 return getInterfaces0();
1347 } else {
1348 Class<?>[] interfaces = rd.interfaces;
1349 if (interfaces == null) {
1350 interfaces = getInterfaces0();
1351 rd.interfaces = interfaces;
1352 }
1353 // defensively copy if requested
1354 return cloneArray ? interfaces.clone() : interfaces;
1355 }
1356 }
1357
1358 private native Class<?>[] getInterfaces0();
1359
1360 /**
1361 * Returns the {@code Type}s representing the interfaces
1362 * directly implemented by the class or interface represented by
1363 * this {@code Class} object.
1364 *
1365 * <p>If a superinterface is a parameterized type, the
1366 * {@code Type} object returned for it must accurately reflect
1367 * the actual type arguments used in the source code. The
1368 * parameterized type representing each superinterface is created
1369 * if it had not been created before. See the declaration of
1370 * {@link java.lang.reflect.ParameterizedType ParameterizedType}
1371 * for the semantics of the creation process for parameterized
1372 * types.
1373 *
1374 * <p>If this {@code Class} object represents a class, the return value is an array
1375 * containing objects representing all interfaces directly implemented by
1376 * the class. The order of the interface objects in the array corresponds
1377 * to the order of the interface names in the {@code implements} clause of
1378 * the declaration of the class represented by this {@code Class} object.
1379 *
1380 * <p>If this {@code Class} object represents an interface, the array contains objects
1381 * representing all interfaces directly extended by the interface. The
1382 * order of the interface objects in the array corresponds to the order of
1383 * the interface names in the {@code extends} clause of the declaration of
1384 * the interface represented by this {@code Class} object.
1385 *
1386 * <p>If this {@code Class} object represents a class or interface that implements no
1387 * interfaces, the method returns an array of length 0.
1388 *
1389 * <p>If this {@code Class} object represents a primitive type or void, the method
1390 * returns an array of length 0.
1391 *
1392 * <p>If this {@code Class} object represents an array type, the
1393 * interfaces {@code Cloneable} and {@code java.io.Serializable} are
1394 * returned in that order.
1395 *
1396 * @throws java.lang.reflect.GenericSignatureFormatError
1397 * if the generic class signature does not conform to the
1398 * format specified in section {@jvms 4.7.9} of <cite>The
1399 * Java Virtual Machine Specification</cite>
1400 * @throws TypeNotPresentException if any of the generic
1401 * superinterfaces refers to a non-existent type declaration
1402 * @throws java.lang.reflect.MalformedParameterizedTypeException
1403 * if any of the generic superinterfaces refer to a parameterized
1404 * type that cannot be instantiated for any reason
1405 * @return an array of interfaces directly implemented by this class
1406 * @since 1.5
1407 */
1408 public Type[] getGenericInterfaces() {
1409 ClassRepository info = getGenericInfo();
1410 return (info == null) ? getInterfaces() : info.getSuperInterfaces();
1411 }
1412
1413
1414 /**
1415 * Returns the {@code Class} representing the component type of an
1416 * array. If this class does not represent an array class this method
1417 * returns null.
1418 *
1419 * @return the {@code Class} representing the component type of this
1420 * class if this class is an array
1421 * @see java.lang.reflect.Array
1422 * @since 1.1
1423 */
1424 public Class<?> getComponentType() {
1425 // Only return for array types. Storage may be reused for Class for instance types.
1426 if (isArray()) {
1427 return componentType;
1428 } else {
1429 return null;
1430 }
1431 }
1432
1433 private final Class<?> componentType;
1434
1435 /*
1436 * Returns the {@code Class} representing the element type of an array class.
1437 * If this class does not represent an array class, then this method returns
1438 * {@code null}.
1439 */
1440 private Class<?> elementType() {
1441 if (!isArray()) return null;
1442
1443 Class<?> c = this;
1444 while (c.isArray()) {
1445 c = c.getComponentType();
1446 }
1447 return c;
1448 }
1449
1450 /**
1451 * Returns the Java language modifiers for this class or interface, encoded
1452 * in an integer. The modifiers consist of the Java Virtual Machine's
1453 * constants for {@code public}, {@code protected},
1454 * {@code private}, {@code final}, {@code static},
1455 * {@code abstract} and {@code interface}; they should be decoded
1456 * using the methods of class {@code Modifier}.
1457 *
1458 * <p> If the underlying class is an array class:
1459 * <ul>
1460 * <li> its {@code public}, {@code private} and {@code protected}
1461 * modifiers are the same as those of its component type
1462 * <li> its {@code abstract} and {@code final} modifiers are always
1463 * {@code true}
1464 * <li> its interface modifier is always {@code false}, even when
1465 * the component type is an interface
1466 * </ul>
1467 * If this {@code Class} object represents a primitive type or
1468 * void, its {@code public}, {@code abstract}, and {@code final}
1469 * modifiers are always {@code true}.
1470 * For {@code Class} objects representing void, primitive types, and
1471 * arrays, the values of other modifiers are {@code false} other
1472 * than as specified above.
1473 *
1474 * <p> The modifier encodings are defined in section {@jvms 4.1}
1475 * of <cite>The Java Virtual Machine Specification</cite>.
1476 *
1477 * @return the {@code int} representing the modifiers for this class
1478 * @see java.lang.reflect.Modifier
1479 * @see #accessFlags()
1480 * @see <a
1481 * href="{@docRoot}/java.base/java/lang/reflect/package-summary.html#LanguageJvmModel">Java
1482 * programming language and JVM modeling in core reflection</a>
1483 * @since 1.1
1484 * @jls 8.1.1 Class Modifiers
1485 * @jls 9.1.1 Interface Modifiers
1486 * @jvms 4.1 The {@code ClassFile} Structure
1487 */
1488 @IntrinsicCandidate
1489 public native int getModifiers();
1490
1491 /**
1492 * {@return an unmodifiable set of the {@linkplain AccessFlag access
1493 * flags} for this class, possibly empty}
1494 *
1495 * <p> If the underlying class is an array class:
1496 * <ul>
1497 * <li> its {@code PUBLIC}, {@code PRIVATE} and {@code PROTECTED}
1498 * access flags are the same as those of its component type
1499 * <li> its {@code ABSTRACT} and {@code FINAL} flags are present
1500 * <li> its {@code INTERFACE} flag is absent, even when the
1501 * component type is an interface
1502 * </ul>
1503 * If this {@code Class} object represents a primitive type or
1504 * void, the flags are {@code PUBLIC}, {@code ABSTRACT}, and
1505 * {@code FINAL}.
1506 * For {@code Class} objects representing void, primitive types, and
1507 * arrays, access flags are absent other than as specified above.
1508 *
1509 * @see #getModifiers()
1510 * @jvms 4.1 The ClassFile Structure
1511 * @jvms 4.7.6 The InnerClasses Attribute
1512 * @since 20
1513 */
1514 public Set<AccessFlag> accessFlags() {
1515 // Location.CLASS allows SUPER and AccessFlag.MODULE which
1516 // INNER_CLASS forbids. INNER_CLASS allows PRIVATE, PROTECTED,
1517 // and STATIC, which are not allowed on Location.CLASS.
1518 // Use getClassAccessFlagsRaw to expose SUPER status.
1519 var location = (isMemberClass() || isLocalClass() ||
1520 isAnonymousClass() || isArray()) ?
1521 AccessFlag.Location.INNER_CLASS :
1522 AccessFlag.Location.CLASS;
1523 return AccessFlag.maskToAccessFlags((location == AccessFlag.Location.CLASS) ?
1524 getClassAccessFlagsRaw() :
1525 getModifiers(),
1526 location);
1527 }
1528
1529 /**
1530 * Gets the signers of this class.
1531 *
1532 * @return the signers of this class, or null if there are no signers. In
1533 * particular, this method returns null if this {@code Class} object represents
1534 * a primitive type or void.
1535 * @since 1.1
1536 */
1537 public Object[] getSigners() {
1538 var signers = this.signers;
1539 return signers == null ? null : signers.clone();
1540 }
1541
1542 /**
1543 * Set the signers of this class.
1544 */
1545 void setSigners(Object[] signers) {
1546 if (!isPrimitive() && !isArray()) {
1547 this.signers = signers;
1548 }
1549 }
1550
1551 /**
1552 * If this {@code Class} object represents a local or anonymous
1553 * class within a method, returns a {@link
1554 * java.lang.reflect.Method Method} object representing the
1555 * immediately enclosing method of the underlying class. Returns
1556 * {@code null} otherwise.
1557 *
1558 * In particular, this method returns {@code null} if the underlying
1559 * class is a local or anonymous class immediately enclosed by a class or
1560 * interface declaration, instance initializer or static initializer.
1561 *
1562 * @return the immediately enclosing method of the underlying class, if
1563 * that class is a local or anonymous class; otherwise {@code null}.
1564 *
1565 * @throws SecurityException
1566 * If a security manager, <i>s</i>, is present and any of the
1567 * following conditions is met:
1568 *
1569 * <ul>
1570 *
1571 * <li> the caller's class loader is not the same as the
1572 * class loader of the enclosing class and invocation of
1573 * {@link SecurityManager#checkPermission
1574 * s.checkPermission} method with
1575 * {@code RuntimePermission("accessDeclaredMembers")}
1576 * denies access to the methods within the enclosing class
1577 *
1578 * <li> the caller's class loader is not the same as or an
1579 * ancestor of the class loader for the enclosing class and
1580 * invocation of {@link SecurityManager#checkPackageAccess
1581 * s.checkPackageAccess()} denies access to the package
1582 * of the enclosing class
1583 *
1584 * </ul>
1585 * @since 1.5
1586 */
1587 @CallerSensitive
1588 public Method getEnclosingMethod() throws SecurityException {
1589 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1590
1591 if (enclosingInfo == null)
1592 return null;
1593 else {
1594 if (!enclosingInfo.isMethod())
1595 return null;
1596
1597 MethodRepository typeInfo = MethodRepository.make(enclosingInfo.getDescriptor(),
1598 getFactory());
1599 Class<?> returnType = toClass(typeInfo.getReturnType());
1600 Type [] parameterTypes = typeInfo.getParameterTypes();
1601 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length];
1602
1603 // Convert Types to Classes; returned types *should*
1604 // be class objects since the methodDescriptor's used
1605 // don't have generics information
1606 for(int i = 0; i < parameterClasses.length; i++)
1607 parameterClasses[i] = toClass(parameterTypes[i]);
1608
1609 // Perform access check
1610 final Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass();
1611 @SuppressWarnings("removal")
1612 SecurityManager sm = System.getSecurityManager();
1613 if (sm != null) {
1614 enclosingCandidate.checkMemberAccess(sm, Member.DECLARED,
1615 Reflection.getCallerClass(), true);
1616 }
1617 Method[] candidates = enclosingCandidate.privateGetDeclaredMethods(false);
1618
1619 /*
1620 * Loop over all declared methods; match method name,
1621 * number of and type of parameters, *and* return
1622 * type. Matching return type is also necessary
1623 * because of covariant returns, etc.
1624 */
1625 ReflectionFactory fact = getReflectionFactory();
1626 for (Method m : candidates) {
1627 if (m.getName().equals(enclosingInfo.getName()) &&
1628 arrayContentsEq(parameterClasses,
1629 fact.getExecutableSharedParameterTypes(m))) {
1630 // finally, check return type
1631 if (m.getReturnType().equals(returnType)) {
1632 return fact.copyMethod(m);
1633 }
1634 }
1635 }
1636
1637 throw new InternalError("Enclosing method not found");
1638 }
1639 }
1640
1641 private native Object[] getEnclosingMethod0();
1642
1643 private EnclosingMethodInfo getEnclosingMethodInfo() {
1644 Object[] enclosingInfo = getEnclosingMethod0();
1645 if (enclosingInfo == null)
1646 return null;
1647 else {
1648 return new EnclosingMethodInfo(enclosingInfo);
1649 }
1650 }
1651
1652 private static final class EnclosingMethodInfo {
1653 private final Class<?> enclosingClass;
1654 private final String name;
1655 private final String descriptor;
1656
1657 static void validate(Object[] enclosingInfo) {
1658 if (enclosingInfo.length != 3)
1659 throw new InternalError("Malformed enclosing method information");
1660 try {
1661 // The array is expected to have three elements:
1662
1663 // the immediately enclosing class
1664 Class<?> enclosingClass = (Class<?>)enclosingInfo[0];
1665 assert(enclosingClass != null);
1666
1667 // the immediately enclosing method or constructor's
1668 // name (can be null).
1669 String name = (String)enclosingInfo[1];
1670
1671 // the immediately enclosing method or constructor's
1672 // descriptor (null iff name is).
1673 String descriptor = (String)enclosingInfo[2];
1674 assert((name != null && descriptor != null) || name == descriptor);
1675 } catch (ClassCastException cce) {
1676 throw new InternalError("Invalid type in enclosing method information", cce);
1677 }
1678 }
1679
1680 EnclosingMethodInfo(Object[] enclosingInfo) {
1681 validate(enclosingInfo);
1682 this.enclosingClass = (Class<?>)enclosingInfo[0];
1683 this.name = (String)enclosingInfo[1];
1684 this.descriptor = (String)enclosingInfo[2];
1685 }
1686
1687 boolean isPartial() {
1688 return enclosingClass == null || name == null || descriptor == null;
1689 }
1690
1691 boolean isConstructor() { return !isPartial() && ConstantDescs.INIT_NAME.equals(name); }
1692
1693 boolean isMethod() { return !isPartial() && !isConstructor() && !ConstantDescs.CLASS_INIT_NAME.equals(name); }
1694
1695 Class<?> getEnclosingClass() { return enclosingClass; }
1696
1697 String getName() { return name; }
1698
1699 String getDescriptor() { return descriptor; }
1700
1701 }
1702
1703 private static Class<?> toClass(Type o) {
1704 if (o instanceof GenericArrayType gat)
1705 return toClass(gat.getGenericComponentType()).arrayType();
1706 return (Class<?>)o;
1707 }
1708
1709 /**
1710 * If this {@code Class} object represents a local or anonymous
1711 * class within a constructor, returns a {@link
1712 * java.lang.reflect.Constructor Constructor} object representing
1713 * the immediately enclosing constructor of the underlying
1714 * class. Returns {@code null} otherwise. In particular, this
1715 * method returns {@code null} if the underlying class is a local
1716 * or anonymous class immediately enclosed by a class or
1717 * interface declaration, instance initializer or static initializer.
1718 *
1719 * @return the immediately enclosing constructor of the underlying class, if
1720 * that class is a local or anonymous class; otherwise {@code null}.
1721 * @throws SecurityException
1722 * If a security manager, <i>s</i>, is present and any of the
1723 * following conditions is met:
1724 *
1725 * <ul>
1726 *
1727 * <li> the caller's class loader is not the same as the
1728 * class loader of the enclosing class and invocation of
1729 * {@link SecurityManager#checkPermission
1730 * s.checkPermission} method with
1731 * {@code RuntimePermission("accessDeclaredMembers")}
1732 * denies access to the constructors within the enclosing class
1733 *
1734 * <li> the caller's class loader is not the same as or an
1735 * ancestor of the class loader for the enclosing class and
1736 * invocation of {@link SecurityManager#checkPackageAccess
1737 * s.checkPackageAccess()} denies access to the package
1738 * of the enclosing class
1739 *
1740 * </ul>
1741 * @since 1.5
1742 */
1743 @CallerSensitive
1744 public Constructor<?> getEnclosingConstructor() throws SecurityException {
1745 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1746
1747 if (enclosingInfo == null)
1748 return null;
1749 else {
1750 if (!enclosingInfo.isConstructor())
1751 return null;
1752
1753 ConstructorRepository typeInfo = ConstructorRepository.make(enclosingInfo.getDescriptor(),
1754 getFactory());
1755 Type [] parameterTypes = typeInfo.getParameterTypes();
1756 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length];
1757
1758 // Convert Types to Classes; returned types *should*
1759 // be class objects since the methodDescriptor's used
1760 // don't have generics information
1761 for(int i = 0; i < parameterClasses.length; i++)
1762 parameterClasses[i] = toClass(parameterTypes[i]);
1763
1764 // Perform access check
1765 final Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass();
1766 @SuppressWarnings("removal")
1767 SecurityManager sm = System.getSecurityManager();
1768 if (sm != null) {
1769 enclosingCandidate.checkMemberAccess(sm, Member.DECLARED,
1770 Reflection.getCallerClass(), true);
1771 }
1772
1773 Constructor<?>[] candidates = enclosingCandidate
1774 .privateGetDeclaredConstructors(false);
1775 /*
1776 * Loop over all declared constructors; match number
1777 * of and type of parameters.
1778 */
1779 ReflectionFactory fact = getReflectionFactory();
1780 for (Constructor<?> c : candidates) {
1781 if (arrayContentsEq(parameterClasses,
1782 fact.getExecutableSharedParameterTypes(c))) {
1783 return fact.copyConstructor(c);
1784 }
1785 }
1786
1787 throw new InternalError("Enclosing constructor not found");
1788 }
1789 }
1790
1791
1792 /**
1793 * If the class or interface represented by this {@code Class} object
1794 * is a member of another class, returns the {@code Class} object
1795 * representing the class in which it was declared. This method returns
1796 * null if this class or interface is not a member of any other class. If
1797 * this {@code Class} object represents an array class, a primitive
1798 * type, or void, then this method returns null.
1799 *
1800 * @return the declaring class for this class
1801 * @throws SecurityException
1802 * If a security manager, <i>s</i>, is present and the caller's
1803 * class loader is not the same as or an ancestor of the class
1804 * loader for the declaring class and invocation of {@link
1805 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
1806 * denies access to the package of the declaring class
1807 * @since 1.1
1808 */
1809 @CallerSensitive
1810 public Class<?> getDeclaringClass() throws SecurityException {
1811 final Class<?> candidate = getDeclaringClass0();
1812
1813 if (candidate != null) {
1814 @SuppressWarnings("removal")
1815 SecurityManager sm = System.getSecurityManager();
1816 if (sm != null) {
1817 candidate.checkPackageAccess(sm,
1818 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
1819 }
1820 }
1821 return candidate;
1822 }
1823
1824 private native Class<?> getDeclaringClass0();
1825
1826
1827 /**
1828 * Returns the immediately enclosing class of the underlying
1829 * class. If the underlying class is a top level class this
1830 * method returns {@code null}.
1831 * @return the immediately enclosing class of the underlying class
1832 * @throws SecurityException
1833 * If a security manager, <i>s</i>, is present and the caller's
1834 * class loader is not the same as or an ancestor of the class
1835 * loader for the enclosing class and invocation of {@link
1836 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
1837 * denies access to the package of the enclosing class
1838 * @since 1.5
1839 */
1840 @CallerSensitive
1841 public Class<?> getEnclosingClass() throws SecurityException {
1842 // There are five kinds of classes (or interfaces):
1843 // a) Top level classes
1844 // b) Nested classes (static member classes)
1845 // c) Inner classes (non-static member classes)
1846 // d) Local classes (named classes declared within a method)
1847 // e) Anonymous classes
1848
1849
1850 // JVM Spec 4.7.7: A class must have an EnclosingMethod
1851 // attribute if and only if it is a local class or an
1852 // anonymous class.
1853 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1854 Class<?> enclosingCandidate;
1855
1856 if (enclosingInfo == null) {
1857 // This is a top level or a nested class or an inner class (a, b, or c)
1858 enclosingCandidate = getDeclaringClass0();
1859 } else {
1860 Class<?> enclosingClass = enclosingInfo.getEnclosingClass();
1861 // This is a local class or an anonymous class (d or e)
1862 if (enclosingClass == this || enclosingClass == null)
1863 throw new InternalError("Malformed enclosing method information");
1864 else
1865 enclosingCandidate = enclosingClass;
1866 }
1867
1868 if (enclosingCandidate != null) {
1869 @SuppressWarnings("removal")
1870 SecurityManager sm = System.getSecurityManager();
1871 if (sm != null) {
1872 enclosingCandidate.checkPackageAccess(sm,
1873 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
1874 }
1875 }
1876 return enclosingCandidate;
1877 }
1878
1879 /**
1880 * Returns the simple name of the underlying class as given in the
1881 * source code. An empty string is returned if the underlying class is
1882 * {@linkplain #isAnonymousClass() anonymous}.
1883 * A {@linkplain #isSynthetic() synthetic class}, one not present
1884 * in source code, can have a non-empty name including special
1885 * characters, such as "{@code $}".
1886 *
1887 * <p>The simple name of an {@linkplain #isArray() array class} is the simple name of the
1888 * component type with "[]" appended. In particular the simple
1889 * name of an array class whose component type is anonymous is "[]".
1890 *
1891 * @return the simple name of the underlying class
1892 * @since 1.5
1893 */
1894 public String getSimpleName() {
1895 ReflectionData<T> rd = reflectionData();
1896 String simpleName = rd.simpleName;
1897 if (simpleName == null) {
1898 rd.simpleName = simpleName = getSimpleName0();
1899 }
1900 return simpleName;
1901 }
1902
1903 private String getSimpleName0() {
1904 if (isArray()) {
1905 return getComponentType().getSimpleName().concat("[]");
1906 }
1907 String simpleName = getSimpleBinaryName();
1908 if (simpleName == null) { // top level class
1909 simpleName = getName();
1910 simpleName = simpleName.substring(simpleName.lastIndexOf('.') + 1); // strip the package name
1911 }
1912 return simpleName;
1913 }
1914
1915 /**
1916 * Return an informative string for the name of this class or interface.
1917 *
1918 * @return an informative string for the name of this class or interface
1919 * @since 1.8
1920 */
1921 public String getTypeName() {
1922 if (isArray()) {
1923 try {
1924 Class<?> cl = this;
1925 int dimensions = 0;
1926 do {
1927 dimensions++;
1928 cl = cl.getComponentType();
1929 } while (cl.isArray());
1930 return cl.getName().concat("[]".repeat(dimensions));
1931 } catch (Throwable e) { /*FALLTHRU*/ }
1932 }
1933 return getName();
1934 }
1935
1936 /**
1937 * Returns the canonical name of the underlying class as
1938 * defined by <cite>The Java Language Specification</cite>.
1939 * Returns {@code null} if the underlying class does not have a canonical
1940 * name. Classes without canonical names include:
1941 * <ul>
1942 * <li>a {@linkplain #isLocalClass() local class}
1943 * <li>a {@linkplain #isAnonymousClass() anonymous class}
1944 * <li>a {@linkplain #isHidden() hidden class}
1945 * <li>an array whose component type does not have a canonical name</li>
1946 * </ul>
1947 *
1948 * The canonical name for a primitive class is the keyword for the
1949 * corresponding primitive type ({@code byte}, {@code short},
1950 * {@code char}, {@code int}, and so on).
1951 *
1952 * <p>An array type has a canonical name if and only if its
1953 * component type has a canonical name. When an array type has a
1954 * canonical name, it is equal to the canonical name of the
1955 * component type followed by "{@code []}".
1956 *
1957 * @return the canonical name of the underlying class if it exists, and
1958 * {@code null} otherwise.
1959 * @jls 6.7 Fully Qualified Names and Canonical Names
1960 * @since 1.5
1961 */
1962 public String getCanonicalName() {
1963 ReflectionData<T> rd = reflectionData();
1964 String canonicalName = rd.canonicalName;
1965 if (canonicalName == null) {
1966 rd.canonicalName = canonicalName = getCanonicalName0();
1967 }
1968 return canonicalName == ReflectionData.NULL_SENTINEL? null : canonicalName;
1969 }
1970
1971 private String getCanonicalName0() {
1972 if (isArray()) {
1973 String canonicalName = getComponentType().getCanonicalName();
1974 if (canonicalName != null)
1975 return canonicalName.concat("[]");
1976 else
1977 return ReflectionData.NULL_SENTINEL;
1978 }
1979 if (isHidden() || isLocalOrAnonymousClass())
1980 return ReflectionData.NULL_SENTINEL;
1981 Class<?> enclosingClass = getEnclosingClass();
1982 if (enclosingClass == null) { // top level class
1983 return getName();
1984 } else {
1985 String enclosingName = enclosingClass.getCanonicalName();
1986 if (enclosingName == null)
1987 return ReflectionData.NULL_SENTINEL;
1988 String simpleName = getSimpleName();
1989 return new StringBuilder(enclosingName.length() + simpleName.length() + 1)
1990 .append(enclosingName)
1991 .append('.')
1992 .append(simpleName)
1993 .toString();
1994 }
1995 }
1996
1997 /**
1998 * Returns {@code true} if and only if the underlying class
1999 * is an anonymous class.
2000 *
2001 * @apiNote
2002 * An anonymous class is not a {@linkplain #isHidden() hidden class}.
2003 *
2004 * @return {@code true} if and only if this class is an anonymous class.
2005 * @since 1.5
2006 * @jls 15.9.5 Anonymous Class Declarations
2007 */
2008 public boolean isAnonymousClass() {
2009 return !isArray() && isLocalOrAnonymousClass() &&
2010 getSimpleBinaryName0() == null;
2011 }
2012
2013 /**
2014 * Returns {@code true} if and only if the underlying class
2015 * is a local class.
2016 *
2017 * @return {@code true} if and only if this class is a local class.
2018 * @since 1.5
2019 * @jls 14.3 Local Class and Interface Declarations
2020 */
2021 public boolean isLocalClass() {
2022 return isLocalOrAnonymousClass() &&
2023 (isArray() || getSimpleBinaryName0() != null);
2024 }
2025
2026 /**
2027 * Returns {@code true} if and only if the underlying class
2028 * is a member class.
2029 *
2030 * @return {@code true} if and only if this class is a member class.
2031 * @since 1.5
2032 * @jls 8.5 Member Class and Interface Declarations
2033 */
2034 public boolean isMemberClass() {
2035 return !isLocalOrAnonymousClass() && getDeclaringClass0() != null;
2036 }
2037
2038 /**
2039 * Returns the "simple binary name" of the underlying class, i.e.,
2040 * the binary name without the leading enclosing class name.
2041 * Returns {@code null} if the underlying class is a top level
2042 * class.
2043 */
2044 private String getSimpleBinaryName() {
2045 if (isTopLevelClass())
2046 return null;
2047 String name = getSimpleBinaryName0();
2048 if (name == null) // anonymous class
2049 return "";
2050 return name;
2051 }
2052
2053 private native String getSimpleBinaryName0();
2054
2055 /**
2056 * Returns {@code true} if this is a top level class. Returns {@code false}
2057 * otherwise.
2058 */
2059 private boolean isTopLevelClass() {
2060 return !isLocalOrAnonymousClass() && getDeclaringClass0() == null;
2061 }
2062
2063 /**
2064 * Returns {@code true} if this is a local class or an anonymous
2065 * class. Returns {@code false} otherwise.
2066 */
2067 private boolean isLocalOrAnonymousClass() {
2068 // JVM Spec 4.7.7: A class must have an EnclosingMethod
2069 // attribute if and only if it is a local class or an
2070 // anonymous class.
2071 return hasEnclosingMethodInfo();
2072 }
2073
2074 private boolean hasEnclosingMethodInfo() {
2075 Object[] enclosingInfo = getEnclosingMethod0();
2076 if (enclosingInfo != null) {
2077 EnclosingMethodInfo.validate(enclosingInfo);
2078 return true;
2079 }
2080 return false;
2081 }
2082
2083 /**
2084 * Returns an array containing {@code Class} objects representing all
2085 * the public classes and interfaces that are members of the class
2086 * represented by this {@code Class} object. This includes public
2087 * class and interface members inherited from superclasses and public class
2088 * and interface members declared by the class. This method returns an
2089 * array of length 0 if this {@code Class} object has no public member
2090 * classes or interfaces. This method also returns an array of length 0 if
2091 * this {@code Class} object represents a primitive type, an array
2092 * class, or void.
2093 *
2094 * @return the array of {@code Class} objects representing the public
2095 * members of this class
2096 * @throws SecurityException
2097 * If a security manager, <i>s</i>, is present and
2098 * the caller's class loader is not the same as or an
2099 * ancestor of the class loader for the current class and
2100 * invocation of {@link SecurityManager#checkPackageAccess
2101 * s.checkPackageAccess()} denies access to the package
2102 * of this class.
2103 *
2104 * @since 1.1
2105 */
2106 @SuppressWarnings("removal")
2107 @CallerSensitive
2108 public Class<?>[] getClasses() {
2109 SecurityManager sm = System.getSecurityManager();
2110 if (sm != null) {
2111 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), false);
2112 }
2113
2114 // Privileged so this implementation can look at DECLARED classes,
2115 // something the caller might not have privilege to do. The code here
2116 // is allowed to look at DECLARED classes because (1) it does not hand
2117 // out anything other than public members and (2) public member access
2118 // has already been ok'd by the SecurityManager.
2119
2120 return java.security.AccessController.doPrivileged(
2121 new java.security.PrivilegedAction<>() {
2122 public Class<?>[] run() {
2123 List<Class<?>> list = new ArrayList<>();
2124 Class<?> currentClass = Class.this;
2125 while (currentClass != null) {
2126 for (Class<?> m : currentClass.getDeclaredClasses()) {
2127 if (Modifier.isPublic(m.getModifiers())) {
2128 list.add(m);
2129 }
2130 }
2131 currentClass = currentClass.getSuperclass();
2132 }
2133 return list.toArray(new Class<?>[0]);
2134 }
2135 });
2136 }
2137
2138
2139 /**
2140 * Returns an array containing {@code Field} objects reflecting all
2141 * the accessible public fields of the class or interface represented by
2142 * this {@code Class} object.
2143 *
2144 * <p> If this {@code Class} object represents a class or interface with
2145 * no accessible public fields, then this method returns an array of length
2146 * 0.
2147 *
2148 * <p> If this {@code Class} object represents a class, then this method
2149 * returns the public fields of the class and of all its superclasses and
2150 * superinterfaces.
2151 *
2152 * <p> If this {@code Class} object represents an interface, then this
2153 * method returns the fields of the interface and of all its
2154 * superinterfaces.
2155 *
2156 * <p> If this {@code Class} object represents an array type, a primitive
2157 * type, or void, then this method returns an array of length 0.
2158 *
2159 * <p> The elements in the returned array are not sorted and are not in any
2160 * particular order.
2161 *
2162 * @return the array of {@code Field} objects representing the
2163 * public fields
2164 * @throws SecurityException
2165 * If a security manager, <i>s</i>, is present and
2166 * the caller's class loader is not the same as or an
2167 * ancestor of the class loader for the current class and
2168 * invocation of {@link SecurityManager#checkPackageAccess
2169 * s.checkPackageAccess()} denies access to the package
2170 * of this class.
2171 *
2172 * @since 1.1
2173 * @jls 8.2 Class Members
2174 * @jls 8.3 Field Declarations
2175 */
2176 @CallerSensitive
2177 public Field[] getFields() throws SecurityException {
2178 @SuppressWarnings("removal")
2179 SecurityManager sm = System.getSecurityManager();
2180 if (sm != null) {
2181 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2182 }
2183 return copyFields(privateGetPublicFields());
2184 }
2185
2186
2187 /**
2188 * Returns an array containing {@code Method} objects reflecting all the
2189 * public methods of the class or interface represented by this {@code
2190 * Class} object, including those declared by the class or interface and
2191 * those inherited from superclasses and superinterfaces.
2192 *
2193 * <p> If this {@code Class} object represents an array type, then the
2194 * returned array has a {@code Method} object for each of the public
2195 * methods inherited by the array type from {@code Object}. It does not
2196 * contain a {@code Method} object for {@code clone()}.
2197 *
2198 * <p> If this {@code Class} object represents an interface then the
2199 * returned array does not contain any implicitly declared methods from
2200 * {@code Object}. Therefore, if no methods are explicitly declared in
2201 * this interface or any of its superinterfaces then the returned array
2202 * has length 0. (Note that a {@code Class} object which represents a class
2203 * always has public methods, inherited from {@code Object}.)
2204 *
2205 * <p> The returned array never contains methods with names {@value
2206 * ConstantDescs#INIT_NAME} or {@value ConstantDescs#CLASS_INIT_NAME}.
2207 *
2208 * <p> The elements in the returned array are not sorted and are not in any
2209 * particular order.
2210 *
2211 * <p> Generally, the result is computed as with the following 4 step algorithm.
2212 * Let C be the class or interface represented by this {@code Class} object:
2213 * <ol>
2214 * <li> A union of methods is composed of:
2215 * <ol type="a">
2216 * <li> C's declared public instance and static methods as returned by
2217 * {@link #getDeclaredMethods()} and filtered to include only public
2218 * methods.</li>
2219 * <li> If C is a class other than {@code Object}, then include the result
2220 * of invoking this algorithm recursively on the superclass of C.</li>
2221 * <li> Include the results of invoking this algorithm recursively on all
2222 * direct superinterfaces of C, but include only instance methods.</li>
2223 * </ol></li>
2224 * <li> Union from step 1 is partitioned into subsets of methods with same
2225 * signature (name, parameter types) and return type.</li>
2226 * <li> Within each such subset only the most specific methods are selected.
2227 * Let method M be a method from a set of methods with same signature
2228 * and return type. M is most specific if there is no such method
2229 * N != M from the same set, such that N is more specific than M.
2230 * N is more specific than M if:
2231 * <ol type="a">
2232 * <li> N is declared by a class and M is declared by an interface; or</li>
2233 * <li> N and M are both declared by classes or both by interfaces and
2234 * N's declaring type is the same as or a subtype of M's declaring type
2235 * (clearly, if M's and N's declaring types are the same type, then
2236 * M and N are the same method).</li>
2237 * </ol></li>
2238 * <li> The result of this algorithm is the union of all selected methods from
2239 * step 3.</li>
2240 * </ol>
2241 *
2242 * @apiNote There may be more than one method with a particular name
2243 * and parameter types in a class because while the Java language forbids a
2244 * class to declare multiple methods with the same signature but different
2245 * return types, the Java virtual machine does not. This
2246 * increased flexibility in the virtual machine can be used to
2247 * implement various language features. For example, covariant
2248 * returns can be implemented with {@linkplain
2249 * java.lang.reflect.Method#isBridge bridge methods}; the bridge
2250 * method and the overriding method would have the same
2251 * signature but different return types.
2252 *
2253 * @return the array of {@code Method} objects representing the
2254 * public methods of this class
2255 * @throws SecurityException
2256 * If a security manager, <i>s</i>, is present and
2257 * the caller's class loader is not the same as or an
2258 * ancestor of the class loader for the current class and
2259 * invocation of {@link SecurityManager#checkPackageAccess
2260 * s.checkPackageAccess()} denies access to the package
2261 * of this class.
2262 *
2263 * @jls 8.2 Class Members
2264 * @jls 8.4 Method Declarations
2265 * @since 1.1
2266 */
2267 @CallerSensitive
2268 public Method[] getMethods() throws SecurityException {
2269 @SuppressWarnings("removal")
2270 SecurityManager sm = System.getSecurityManager();
2271 if (sm != null) {
2272 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2273 }
2274 return copyMethods(privateGetPublicMethods());
2275 }
2276
2277
2278 /**
2279 * Returns an array containing {@code Constructor} objects reflecting
2280 * all the public constructors of the class represented by this
2281 * {@code Class} object. An array of length 0 is returned if the
2282 * class has no public constructors, or if the class is an array class, or
2283 * if the class reflects a primitive type or void.
2284 *
2285 * @apiNote
2286 * While this method returns an array of {@code
2287 * Constructor<T>} objects (that is an array of constructors from
2288 * this class), the return type of this method is {@code
2289 * Constructor<?>[]} and <em>not</em> {@code Constructor<T>[]} as
2290 * might be expected. This less informative return type is
2291 * necessary since after being returned from this method, the
2292 * array could be modified to hold {@code Constructor} objects for
2293 * different classes, which would violate the type guarantees of
2294 * {@code Constructor<T>[]}.
2295 *
2296 * @return the array of {@code Constructor} objects representing the
2297 * public constructors of this class
2298 * @throws SecurityException
2299 * If a security manager, <i>s</i>, is present and
2300 * the caller's class loader is not the same as or an
2301 * ancestor of the class loader for the current class and
2302 * invocation of {@link SecurityManager#checkPackageAccess
2303 * s.checkPackageAccess()} denies access to the package
2304 * of this class.
2305 *
2306 * @see #getDeclaredConstructors()
2307 * @since 1.1
2308 */
2309 @CallerSensitive
2310 public Constructor<?>[] getConstructors() throws SecurityException {
2311 @SuppressWarnings("removal")
2312 SecurityManager sm = System.getSecurityManager();
2313 if (sm != null) {
2314 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2315 }
2316 return copyConstructors(privateGetDeclaredConstructors(true));
2317 }
2318
2319
2320 /**
2321 * Returns a {@code Field} object that reflects the specified public member
2322 * field of the class or interface represented by this {@code Class}
2323 * object. The {@code name} parameter is a {@code String} specifying the
2324 * simple name of the desired field.
2325 *
2326 * <p> The field to be reflected is determined by the algorithm that
2327 * follows. Let C be the class or interface represented by this {@code Class} object:
2328 *
2329 * <OL>
2330 * <LI> If C declares a public field with the name specified, that is the
2331 * field to be reflected.</LI>
2332 * <LI> If no field was found in step 1 above, this algorithm is applied
2333 * recursively to each direct superinterface of C. The direct
2334 * superinterfaces are searched in the order they were declared.</LI>
2335 * <LI> If no field was found in steps 1 and 2 above, and C has a
2336 * superclass S, then this algorithm is invoked recursively upon S.
2337 * If C has no superclass, then a {@code NoSuchFieldException}
2338 * is thrown.</LI>
2339 * </OL>
2340 *
2341 * <p> If this {@code Class} object represents an array type, then this
2342 * method does not find the {@code length} field of the array type.
2343 *
2344 * @param name the field name
2345 * @return the {@code Field} object of this class specified by
2346 * {@code name}
2347 * @throws NoSuchFieldException if a field with the specified name is
2348 * not found.
2349 * @throws NullPointerException if {@code name} is {@code null}
2350 * @throws SecurityException
2351 * If a security manager, <i>s</i>, is present and
2352 * the caller's class loader is not the same as or an
2353 * ancestor of the class loader for the current class and
2354 * invocation of {@link SecurityManager#checkPackageAccess
2355 * s.checkPackageAccess()} denies access to the package
2356 * of this class.
2357 *
2358 * @since 1.1
2359 * @jls 8.2 Class Members
2360 * @jls 8.3 Field Declarations
2361 */
2362 @CallerSensitive
2363 public Field getField(String name)
2364 throws NoSuchFieldException, SecurityException {
2365 Objects.requireNonNull(name);
2366 @SuppressWarnings("removal")
2367 SecurityManager sm = System.getSecurityManager();
2368 if (sm != null) {
2369 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2370 }
2371 Field field = getField0(name);
2372 if (field == null) {
2373 throw new NoSuchFieldException(name);
2374 }
2375 return getReflectionFactory().copyField(field);
2376 }
2377
2378
2379 /**
2380 * Returns a {@code Method} object that reflects the specified public
2381 * member method of the class or interface represented by this
2382 * {@code Class} object. The {@code name} parameter is a
2383 * {@code String} specifying the simple name of the desired method. The
2384 * {@code parameterTypes} parameter is an array of {@code Class}
2385 * objects that identify the method's formal parameter types, in declared
2386 * order. If {@code parameterTypes} is {@code null}, it is
2387 * treated as if it were an empty array.
2388 *
2389 * <p> If this {@code Class} object represents an array type, then this
2390 * method finds any public method inherited by the array type from
2391 * {@code Object} except method {@code clone()}.
2392 *
2393 * <p> If this {@code Class} object represents an interface then this
2394 * method does not find any implicitly declared method from
2395 * {@code Object}. Therefore, if no methods are explicitly declared in
2396 * this interface or any of its superinterfaces, then this method does not
2397 * find any method.
2398 *
2399 * <p> This method does not find any method with name {@value
2400 * ConstantDescs#INIT_NAME} or {@value ConstantDescs#CLASS_INIT_NAME}.
2401 *
2402 * <p> Generally, the method to be reflected is determined by the 4 step
2403 * algorithm that follows.
2404 * Let C be the class or interface represented by this {@code Class} object:
2405 * <ol>
2406 * <li> A union of methods is composed of:
2407 * <ol type="a">
2408 * <li> C's declared public instance and static methods as returned by
2409 * {@link #getDeclaredMethods()} and filtered to include only public
2410 * methods that match given {@code name} and {@code parameterTypes}</li>
2411 * <li> If C is a class other than {@code Object}, then include the result
2412 * of invoking this algorithm recursively on the superclass of C.</li>
2413 * <li> Include the results of invoking this algorithm recursively on all
2414 * direct superinterfaces of C, but include only instance methods.</li>
2415 * </ol></li>
2416 * <li> This union is partitioned into subsets of methods with same
2417 * return type (the selection of methods from step 1 also guarantees that
2418 * they have the same method name and parameter types).</li>
2419 * <li> Within each such subset only the most specific methods are selected.
2420 * Let method M be a method from a set of methods with same VM
2421 * signature (return type, name, parameter types).
2422 * M is most specific if there is no such method N != M from the same
2423 * set, such that N is more specific than M. N is more specific than M
2424 * if:
2425 * <ol type="a">
2426 * <li> N is declared by a class and M is declared by an interface; or</li>
2427 * <li> N and M are both declared by classes or both by interfaces and
2428 * N's declaring type is the same as or a subtype of M's declaring type
2429 * (clearly, if M's and N's declaring types are the same type, then
2430 * M and N are the same method).</li>
2431 * </ol></li>
2432 * <li> The result of this algorithm is chosen arbitrarily from the methods
2433 * with most specific return type among all selected methods from step 3.
2434 * Let R be a return type of a method M from the set of all selected methods
2435 * from step 3. M is a method with most specific return type if there is
2436 * no such method N != M from the same set, having return type S != R,
2437 * such that S is a subtype of R as determined by
2438 * R.class.{@link #isAssignableFrom}(S.class).
2439 * </ol>
2440 *
2441 * @apiNote There may be more than one method with matching name and
2442 * parameter types in a class because while the Java language forbids a
2443 * class to declare multiple methods with the same signature but different
2444 * return types, the Java virtual machine does not. This
2445 * increased flexibility in the virtual machine can be used to
2446 * implement various language features. For example, covariant
2447 * returns can be implemented with {@linkplain
2448 * java.lang.reflect.Method#isBridge bridge methods}; the bridge
2449 * method and the overriding method would have the same
2450 * signature but different return types. This method would return the
2451 * overriding method as it would have a more specific return type.
2452 *
2453 * @param name the name of the method
2454 * @param parameterTypes the list of parameters
2455 * @return the {@code Method} object that matches the specified
2456 * {@code name} and {@code parameterTypes}
2457 * @throws NoSuchMethodException if a matching method is not found
2458 * or if the name is {@value ConstantDescs#INIT_NAME} or
2459 * {@value ConstantDescs#CLASS_INIT_NAME}.
2460 * @throws NullPointerException if {@code name} is {@code null}
2461 * @throws SecurityException
2462 * If a security manager, <i>s</i>, is present and
2463 * the caller's class loader is not the same as or an
2464 * ancestor of the class loader for the current class and
2465 * invocation of {@link SecurityManager#checkPackageAccess
2466 * s.checkPackageAccess()} denies access to the package
2467 * of this class.
2468 *
2469 * @jls 8.2 Class Members
2470 * @jls 8.4 Method Declarations
2471 * @since 1.1
2472 */
2473 @CallerSensitive
2474 public Method getMethod(String name, Class<?>... parameterTypes)
2475 throws NoSuchMethodException, SecurityException {
2476 Objects.requireNonNull(name);
2477 @SuppressWarnings("removal")
2478 SecurityManager sm = System.getSecurityManager();
2479 if (sm != null) {
2480 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2481 }
2482 Method method = getMethod0(name, parameterTypes);
2483 if (method == null) {
2484 throw new NoSuchMethodException(methodToString(name, parameterTypes));
2485 }
2486 return getReflectionFactory().copyMethod(method);
2487 }
2488
2489 /**
2490 * Returns a {@code Constructor} object that reflects the specified
2491 * public constructor of the class represented by this {@code Class}
2492 * object. The {@code parameterTypes} parameter is an array of
2493 * {@code Class} objects that identify the constructor's formal
2494 * parameter types, in declared order.
2495 *
2496 * If this {@code Class} object represents an inner class
2497 * declared in a non-static context, the formal parameter types
2498 * include the explicit enclosing instance as the first parameter.
2499 *
2500 * <p> The constructor to reflect is the public constructor of the class
2501 * represented by this {@code Class} object whose formal parameter
2502 * types match those specified by {@code parameterTypes}.
2503 *
2504 * @param parameterTypes the parameter array
2505 * @return the {@code Constructor} object of the public constructor that
2506 * matches the specified {@code parameterTypes}
2507 * @throws NoSuchMethodException if a matching constructor is not found,
2508 * including when this {@code Class} object represents
2509 * an interface, a primitive type, an array class, or void.
2510 * @throws SecurityException
2511 * If a security manager, <i>s</i>, is present and
2512 * the caller's class loader is not the same as or an
2513 * ancestor of the class loader for the current class and
2514 * invocation of {@link SecurityManager#checkPackageAccess
2515 * s.checkPackageAccess()} denies access to the package
2516 * of this class.
2517 *
2518 * @see #getDeclaredConstructor(Class<?>[])
2519 * @since 1.1
2520 */
2521 @CallerSensitive
2522 public Constructor<T> getConstructor(Class<?>... parameterTypes)
2523 throws NoSuchMethodException, SecurityException
2524 {
2525 @SuppressWarnings("removal")
2526 SecurityManager sm = System.getSecurityManager();
2527 if (sm != null) {
2528 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2529 }
2530 return getReflectionFactory().copyConstructor(
2531 getConstructor0(parameterTypes, Member.PUBLIC));
2532 }
2533
2534
2535 /**
2536 * Returns an array of {@code Class} objects reflecting all the
2537 * classes and interfaces declared as members of the class represented by
2538 * this {@code Class} object. This includes public, protected, default
2539 * (package) access, and private classes and interfaces declared by the
2540 * class, but excludes inherited classes and interfaces. This method
2541 * returns an array of length 0 if the class declares no classes or
2542 * interfaces as members, or if this {@code Class} object represents a
2543 * primitive type, an array class, or void.
2544 *
2545 * @return the array of {@code Class} objects representing all the
2546 * declared members of this class
2547 * @throws SecurityException
2548 * If a security manager, <i>s</i>, is present and any of the
2549 * following conditions is met:
2550 *
2551 * <ul>
2552 *
2553 * <li> the caller's class loader is not the same as the
2554 * class loader of this class and invocation of
2555 * {@link SecurityManager#checkPermission
2556 * s.checkPermission} method with
2557 * {@code RuntimePermission("accessDeclaredMembers")}
2558 * denies access to the declared classes within this class
2559 *
2560 * <li> the caller's class loader is not the same as or an
2561 * ancestor of the class loader for the current class and
2562 * invocation of {@link SecurityManager#checkPackageAccess
2563 * s.checkPackageAccess()} denies access to the package
2564 * of this class
2565 *
2566 * </ul>
2567 *
2568 * @since 1.1
2569 * @jls 8.5 Member Class and Interface Declarations
2570 */
2571 @CallerSensitive
2572 public Class<?>[] getDeclaredClasses() throws SecurityException {
2573 @SuppressWarnings("removal")
2574 SecurityManager sm = System.getSecurityManager();
2575 if (sm != null) {
2576 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), false);
2577 }
2578 return getDeclaredClasses0();
2579 }
2580
2581
2582 /**
2583 * Returns an array of {@code Field} objects reflecting all the fields
2584 * declared by the class or interface represented by this
2585 * {@code Class} object. This includes public, protected, default
2586 * (package) access, and private fields, but excludes inherited fields.
2587 *
2588 * <p> If this {@code Class} object represents a class or interface with no
2589 * declared fields, then this method returns an array of length 0.
2590 *
2591 * <p> If this {@code Class} object represents an array type, a primitive
2592 * type, or void, then this method returns an array of length 0.
2593 *
2594 * <p> The elements in the returned array are not sorted and are not in any
2595 * particular order.
2596 *
2597 * @return the array of {@code Field} objects representing all the
2598 * declared fields of this class
2599 * @throws SecurityException
2600 * If a security manager, <i>s</i>, is present and any of the
2601 * following conditions is met:
2602 *
2603 * <ul>
2604 *
2605 * <li> the caller's class loader is not the same as the
2606 * class loader of this class and invocation of
2607 * {@link SecurityManager#checkPermission
2608 * s.checkPermission} method with
2609 * {@code RuntimePermission("accessDeclaredMembers")}
2610 * denies access to the declared fields within this class
2611 *
2612 * <li> the caller's class loader is not the same as or an
2613 * ancestor of the class loader for the current class and
2614 * invocation of {@link SecurityManager#checkPackageAccess
2615 * s.checkPackageAccess()} denies access to the package
2616 * of this class
2617 *
2618 * </ul>
2619 *
2620 * @since 1.1
2621 * @jls 8.2 Class Members
2622 * @jls 8.3 Field Declarations
2623 */
2624 @CallerSensitive
2625 public Field[] getDeclaredFields() throws SecurityException {
2626 @SuppressWarnings("removal")
2627 SecurityManager sm = System.getSecurityManager();
2628 if (sm != null) {
2629 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2630 }
2631 return copyFields(privateGetDeclaredFields(false));
2632 }
2633
2634 /**
2635 * Returns an array of {@code RecordComponent} objects representing all the
2636 * record components of this record class, or {@code null} if this class is
2637 * not a record class.
2638 *
2639 * <p> The components are returned in the same order that they are declared
2640 * in the record header. The array is empty if this record class has no
2641 * components. If the class is not a record class, that is {@link
2642 * #isRecord()} returns {@code false}, then this method returns {@code null}.
2643 * Conversely, if {@link #isRecord()} returns {@code true}, then this method
2644 * returns a non-null value.
2645 *
2646 * @apiNote
2647 * <p> The following method can be used to find the record canonical constructor:
2648 *
2649 * {@snippet lang="java" :
2650 * static <T extends Record> Constructor<T> getCanonicalConstructor(Class<T> cls)
2651 * throws NoSuchMethodException {
2652 * Class<?>[] paramTypes =
2653 * Arrays.stream(cls.getRecordComponents())
2654 * .map(RecordComponent::getType)
2655 * .toArray(Class<?>[]::new);
2656 * return cls.getDeclaredConstructor(paramTypes);
2657 * }}
2658 *
2659 * @return An array of {@code RecordComponent} objects representing all the
2660 * record components of this record class, or {@code null} if this
2661 * class is not a record class
2662 * @throws SecurityException
2663 * If a security manager, <i>s</i>, is present and any of the
2664 * following conditions is met:
2665 *
2666 * <ul>
2667 *
2668 * <li> the caller's class loader is not the same as the
2669 * class loader of this class and invocation of
2670 * {@link SecurityManager#checkPermission
2671 * s.checkPermission} method with
2672 * {@code RuntimePermission("accessDeclaredMembers")}
2673 * denies access to the declared methods within this class
2674 *
2675 * <li> the caller's class loader is not the same as or an
2676 * ancestor of the class loader for the current class and
2677 * invocation of {@link SecurityManager#checkPackageAccess
2678 * s.checkPackageAccess()} denies access to the package
2679 * of this class
2680 *
2681 * </ul>
2682 *
2683 * @jls 8.10 Record Classes
2684 * @since 16
2685 */
2686 @CallerSensitive
2687 public RecordComponent[] getRecordComponents() {
2688 @SuppressWarnings("removal")
2689 SecurityManager sm = System.getSecurityManager();
2690 if (sm != null) {
2691 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2692 }
2693 if (!isRecord()) {
2694 return null;
2695 }
2696 return getRecordComponents0();
2697 }
2698
2699 /**
2700 * Returns an array containing {@code Method} objects reflecting all the
2701 * declared methods of the class or interface represented by this {@code
2702 * Class} object, including public, protected, default (package)
2703 * access, and private methods, but excluding inherited methods.
2704 * The declared methods may include methods <em>not</em> in the
2705 * source of the class or interface, including {@linkplain
2706 * Method#isBridge bridge methods} and other {@linkplain
2707 * Executable#isSynthetic synthetic} methods added by compilers.
2708 *
2709 * <p> If this {@code Class} object represents a class or interface that
2710 * has multiple declared methods with the same name and parameter types,
2711 * but different return types, then the returned array has a {@code Method}
2712 * object for each such method.
2713 *
2714 * <p> If this {@code Class} object represents a class or interface that
2715 * has a class initialization method {@value ConstantDescs#CLASS_INIT_NAME},
2716 * then the returned array does <em>not</em> have a corresponding {@code
2717 * Method} object.
2718 *
2719 * <p> If this {@code Class} object represents a class or interface with no
2720 * declared methods, then the returned array has length 0.
2721 *
2722 * <p> If this {@code Class} object represents an array type, a primitive
2723 * type, or void, then the returned array has length 0.
2724 *
2725 * <p> The elements in the returned array are not sorted and are not in any
2726 * particular order.
2727 *
2728 * @return the array of {@code Method} objects representing all the
2729 * declared methods of this class
2730 * @throws SecurityException
2731 * If a security manager, <i>s</i>, is present and any of the
2732 * following conditions is met:
2733 *
2734 * <ul>
2735 *
2736 * <li> the caller's class loader is not the same as the
2737 * class loader of this class and invocation of
2738 * {@link SecurityManager#checkPermission
2739 * s.checkPermission} method with
2740 * {@code RuntimePermission("accessDeclaredMembers")}
2741 * denies access to the declared methods within this class
2742 *
2743 * <li> the caller's class loader is not the same as or an
2744 * ancestor of the class loader for the current class and
2745 * invocation of {@link SecurityManager#checkPackageAccess
2746 * s.checkPackageAccess()} denies access to the package
2747 * of this class
2748 *
2749 * </ul>
2750 *
2751 * @jls 8.2 Class Members
2752 * @jls 8.4 Method Declarations
2753 * @see <a
2754 * href="{@docRoot}/java.base/java/lang/reflect/package-summary.html#LanguageJvmModel">Java
2755 * programming language and JVM modeling in core reflection</a>
2756 * @since 1.1
2757 */
2758 @CallerSensitive
2759 public Method[] getDeclaredMethods() throws SecurityException {
2760 @SuppressWarnings("removal")
2761 SecurityManager sm = System.getSecurityManager();
2762 if (sm != null) {
2763 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2764 }
2765 return copyMethods(privateGetDeclaredMethods(false));
2766 }
2767
2768 /**
2769 * Returns an array of {@code Constructor} objects reflecting all the
2770 * constructors implicitly or explicitly declared by the class represented by this
2771 * {@code Class} object. These are public, protected, default
2772 * (package) access, and private constructors. The elements in the array
2773 * returned are not sorted and are not in any particular order. If the
2774 * class has a default constructor (JLS {@jls 8.8.9}), it is included in the returned array.
2775 * If a record class has a canonical constructor (JLS {@jls
2776 * 8.10.4.1}, {@jls 8.10.4.2}), it is included in the returned array.
2777 *
2778 * This method returns an array of length 0 if this {@code Class}
2779 * object represents an interface, a primitive type, an array class, or
2780 * void.
2781 *
2782 * @return the array of {@code Constructor} objects representing all the
2783 * declared constructors of this class
2784 * @throws SecurityException
2785 * If a security manager, <i>s</i>, is present and any of the
2786 * following conditions is met:
2787 *
2788 * <ul>
2789 *
2790 * <li> the caller's class loader is not the same as the
2791 * class loader of this class and invocation of
2792 * {@link SecurityManager#checkPermission
2793 * s.checkPermission} method with
2794 * {@code RuntimePermission("accessDeclaredMembers")}
2795 * denies access to the declared constructors within this class
2796 *
2797 * <li> the caller's class loader is not the same as or an
2798 * ancestor of the class loader for the current class and
2799 * invocation of {@link SecurityManager#checkPackageAccess
2800 * s.checkPackageAccess()} denies access to the package
2801 * of this class
2802 *
2803 * </ul>
2804 *
2805 * @since 1.1
2806 * @see #getConstructors()
2807 * @jls 8.8 Constructor Declarations
2808 */
2809 @CallerSensitive
2810 public Constructor<?>[] getDeclaredConstructors() throws SecurityException {
2811 @SuppressWarnings("removal")
2812 SecurityManager sm = System.getSecurityManager();
2813 if (sm != null) {
2814 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2815 }
2816 return copyConstructors(privateGetDeclaredConstructors(false));
2817 }
2818
2819
2820 /**
2821 * Returns a {@code Field} object that reflects the specified declared
2822 * field of the class or interface represented by this {@code Class}
2823 * object. The {@code name} parameter is a {@code String} that specifies
2824 * the simple name of the desired field.
2825 *
2826 * <p> If this {@code Class} object represents an array type, then this
2827 * method does not find the {@code length} field of the array type.
2828 *
2829 * @param name the name of the field
2830 * @return the {@code Field} object for the specified field in this
2831 * class
2832 * @throws NoSuchFieldException if a field with the specified name is
2833 * not found.
2834 * @throws NullPointerException if {@code name} is {@code null}
2835 * @throws SecurityException
2836 * If a security manager, <i>s</i>, is present and any of the
2837 * following conditions is met:
2838 *
2839 * <ul>
2840 *
2841 * <li> the caller's class loader is not the same as the
2842 * class loader of this class and invocation of
2843 * {@link SecurityManager#checkPermission
2844 * s.checkPermission} method with
2845 * {@code RuntimePermission("accessDeclaredMembers")}
2846 * denies access to the declared field
2847 *
2848 * <li> the caller's class loader is not the same as or an
2849 * ancestor of the class loader for the current class and
2850 * invocation of {@link SecurityManager#checkPackageAccess
2851 * s.checkPackageAccess()} denies access to the package
2852 * of this class
2853 *
2854 * </ul>
2855 *
2856 * @since 1.1
2857 * @jls 8.2 Class Members
2858 * @jls 8.3 Field Declarations
2859 */
2860 @CallerSensitive
2861 public Field getDeclaredField(String name)
2862 throws NoSuchFieldException, SecurityException {
2863 Objects.requireNonNull(name);
2864 @SuppressWarnings("removal")
2865 SecurityManager sm = System.getSecurityManager();
2866 if (sm != null) {
2867 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2868 }
2869 Field field = searchFields(privateGetDeclaredFields(false), name);
2870 if (field == null) {
2871 throw new NoSuchFieldException(name);
2872 }
2873 return getReflectionFactory().copyField(field);
2874 }
2875
2876
2877 /**
2878 * Returns a {@code Method} object that reflects the specified
2879 * declared method of the class or interface represented by this
2880 * {@code Class} object. The {@code name} parameter is a
2881 * {@code String} that specifies the simple name of the desired
2882 * method, and the {@code parameterTypes} parameter is an array of
2883 * {@code Class} objects that identify the method's formal parameter
2884 * types, in declared order. If more than one method with the same
2885 * parameter types is declared in a class, and one of these methods has a
2886 * return type that is more specific than any of the others, that method is
2887 * returned; otherwise one of the methods is chosen arbitrarily. If the
2888 * name is {@value ConstantDescs#INIT_NAME} or {@value
2889 * ConstantDescs#CLASS_INIT_NAME} a {@code NoSuchMethodException}
2890 * is raised.
2891 *
2892 * <p> If this {@code Class} object represents an array type, then this
2893 * method does not find the {@code clone()} method.
2894 *
2895 * @param name the name of the method
2896 * @param parameterTypes the parameter array
2897 * @return the {@code Method} object for the method of this class
2898 * matching the specified name and parameters
2899 * @throws NoSuchMethodException if a matching method is not found.
2900 * @throws NullPointerException if {@code name} is {@code null}
2901 * @throws SecurityException
2902 * If a security manager, <i>s</i>, is present and any of the
2903 * following conditions is met:
2904 *
2905 * <ul>
2906 *
2907 * <li> the caller's class loader is not the same as the
2908 * class loader of this class and invocation of
2909 * {@link SecurityManager#checkPermission
2910 * s.checkPermission} method with
2911 * {@code RuntimePermission("accessDeclaredMembers")}
2912 * denies access to the declared method
2913 *
2914 * <li> the caller's class loader is not the same as or an
2915 * ancestor of the class loader for the current class and
2916 * invocation of {@link SecurityManager#checkPackageAccess
2917 * s.checkPackageAccess()} denies access to the package
2918 * of this class
2919 *
2920 * </ul>
2921 *
2922 * @jls 8.2 Class Members
2923 * @jls 8.4 Method Declarations
2924 * @since 1.1
2925 */
2926 @CallerSensitive
2927 public Method getDeclaredMethod(String name, Class<?>... parameterTypes)
2928 throws NoSuchMethodException, SecurityException {
2929 Objects.requireNonNull(name);
2930 @SuppressWarnings("removal")
2931 SecurityManager sm = System.getSecurityManager();
2932 if (sm != null) {
2933 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2934 }
2935 Method method = searchMethods(privateGetDeclaredMethods(false), name, parameterTypes);
2936 if (method == null) {
2937 throw new NoSuchMethodException(methodToString(name, parameterTypes));
2938 }
2939 return getReflectionFactory().copyMethod(method);
2940 }
2941
2942 /**
2943 * Returns the list of {@code Method} objects for the declared public
2944 * methods of this class or interface that have the specified method name
2945 * and parameter types.
2946 *
2947 * @param name the name of the method
2948 * @param parameterTypes the parameter array
2949 * @return the list of {@code Method} objects for the public methods of
2950 * this class matching the specified name and parameters
2951 */
2952 List<Method> getDeclaredPublicMethods(String name, Class<?>... parameterTypes) {
2953 Method[] methods = privateGetDeclaredMethods(/* publicOnly */ true);
2954 ReflectionFactory factory = getReflectionFactory();
2955 List<Method> result = new ArrayList<>();
2956 for (Method method : methods) {
2957 if (method.getName().equals(name)
2958 && Arrays.equals(
2959 factory.getExecutableSharedParameterTypes(method),
2960 parameterTypes)) {
2961 result.add(factory.copyMethod(method));
2962 }
2963 }
2964 return result;
2965 }
2966
2967 /**
2968 * Returns the most specific {@code Method} object of this class, super class or
2969 * interface that have the specified method name and parameter types.
2970 *
2971 * @param publicOnly true if only public methods are examined, otherwise all methods
2972 * @param name the name of the method
2973 * @param parameterTypes the parameter array
2974 * @return the {@code Method} object for the method found from this class matching
2975 * the specified name and parameters, or null if not found
2976 */
2977 Method findMethod(boolean publicOnly, String name, Class<?>... parameterTypes) {
2978 PublicMethods.MethodList res = getMethodsRecursive(name, parameterTypes, true, publicOnly);
2979 return res == null ? null : getReflectionFactory().copyMethod(res.getMostSpecific());
2980 }
2981
2982 /**
2983 * Returns a {@code Constructor} object that reflects the specified
2984 * constructor of the class represented by this
2985 * {@code Class} object. The {@code parameterTypes} parameter is
2986 * an array of {@code Class} objects that identify the constructor's
2987 * formal parameter types, in declared order.
2988 *
2989 * If this {@code Class} object represents an inner class
2990 * declared in a non-static context, the formal parameter types
2991 * include the explicit enclosing instance as the first parameter.
2992 *
2993 * @param parameterTypes the parameter array
2994 * @return The {@code Constructor} object for the constructor with the
2995 * specified parameter list
2996 * @throws NoSuchMethodException if a matching constructor is not found,
2997 * including when this {@code Class} object represents
2998 * an interface, a primitive type, an array class, or void.
2999 * @throws SecurityException
3000 * If a security manager, <i>s</i>, is present and any of the
3001 * following conditions is met:
3002 *
3003 * <ul>
3004 *
3005 * <li> the caller's class loader is not the same as the
3006 * class loader of this class and invocation of
3007 * {@link SecurityManager#checkPermission
3008 * s.checkPermission} method with
3009 * {@code RuntimePermission("accessDeclaredMembers")}
3010 * denies access to the declared constructor
3011 *
3012 * <li> the caller's class loader is not the same as or an
3013 * ancestor of the class loader for the current class and
3014 * invocation of {@link SecurityManager#checkPackageAccess
3015 * s.checkPackageAccess()} denies access to the package
3016 * of this class
3017 *
3018 * </ul>
3019 *
3020 * @see #getConstructor(Class<?>[])
3021 * @since 1.1
3022 */
3023 @CallerSensitive
3024 public Constructor<T> getDeclaredConstructor(Class<?>... parameterTypes)
3025 throws NoSuchMethodException, SecurityException
3026 {
3027 @SuppressWarnings("removal")
3028 SecurityManager sm = System.getSecurityManager();
3029 if (sm != null) {
3030 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
3031 }
3032
3033 return getReflectionFactory().copyConstructor(
3034 getConstructor0(parameterTypes, Member.DECLARED));
3035 }
3036
3037 /**
3038 * Finds a resource with a given name.
3039 *
3040 * <p> If this class is in a named {@link Module Module} then this method
3041 * will attempt to find the resource in the module. This is done by
3042 * delegating to the module's class loader {@link
3043 * ClassLoader#findResource(String,String) findResource(String,String)}
3044 * method, invoking it with the module name and the absolute name of the
3045 * resource. Resources in named modules are subject to the rules for
3046 * encapsulation specified in the {@code Module} {@link
3047 * Module#getResourceAsStream getResourceAsStream} method and so this
3048 * method returns {@code null} when the resource is a
3049 * non-"{@code .class}" resource in a package that is not open to the
3050 * caller's module.
3051 *
3052 * <p> Otherwise, if this class is not in a named module then the rules for
3053 * searching resources associated with a given class are implemented by the
3054 * defining {@linkplain ClassLoader class loader} of the class. This method
3055 * delegates to this {@code Class} object's class loader.
3056 * If this {@code Class} object was loaded by the bootstrap class loader,
3057 * the method delegates to {@link ClassLoader#getSystemResourceAsStream}.
3058 *
3059 * <p> Before delegation, an absolute resource name is constructed from the
3060 * given resource name using this algorithm:
3061 *
3062 * <ul>
3063 *
3064 * <li> If the {@code name} begins with a {@code '/'}
3065 * (<code>'\u002f'</code>), then the absolute name of the resource is the
3066 * portion of the {@code name} following the {@code '/'}.
3067 *
3068 * <li> Otherwise, the absolute name is of the following form:
3069 *
3070 * <blockquote>
3071 * {@code modified_package_name/name}
3072 * </blockquote>
3073 *
3074 * <p> Where the {@code modified_package_name} is the package name of this
3075 * object with {@code '/'} substituted for {@code '.'}
3076 * (<code>'\u002e'</code>).
3077 *
3078 * </ul>
3079 *
3080 * @param name name of the desired resource
3081 * @return A {@link java.io.InputStream} object; {@code null} if no
3082 * resource with this name is found, the resource is in a package
3083 * that is not {@linkplain Module#isOpen(String, Module) open} to at
3084 * least the caller module, or access to the resource is denied
3085 * by the security manager.
3086 * @throws NullPointerException If {@code name} is {@code null}
3087 *
3088 * @see Module#getResourceAsStream(String)
3089 * @since 1.1
3090 */
3091 @CallerSensitive
3092 public InputStream getResourceAsStream(String name) {
3093 name = resolveName(name);
3094
3095 Module thisModule = getModule();
3096 if (thisModule.isNamed()) {
3097 // check if resource can be located by caller
3098 if (Resources.canEncapsulate(name)
3099 && !isOpenToCaller(name, Reflection.getCallerClass())) {
3100 return null;
3101 }
3102
3103 // resource not encapsulated or in package open to caller
3104 String mn = thisModule.getName();
3105 ClassLoader cl = classLoader;
3106 try {
3107
3108 // special-case built-in class loaders to avoid the
3109 // need for a URL connection
3110 if (cl == null) {
3111 return BootLoader.findResourceAsStream(mn, name);
3112 } else if (cl instanceof BuiltinClassLoader bcl) {
3113 return bcl.findResourceAsStream(mn, name);
3114 } else {
3115 URL url = cl.findResource(mn, name);
3116 return (url != null) ? url.openStream() : null;
3117 }
3118
3119 } catch (IOException | SecurityException e) {
3120 return null;
3121 }
3122 }
3123
3124 // unnamed module
3125 ClassLoader cl = classLoader;
3126 if (cl == null) {
3127 return ClassLoader.getSystemResourceAsStream(name);
3128 } else {
3129 return cl.getResourceAsStream(name);
3130 }
3131 }
3132
3133 /**
3134 * Finds a resource with a given name.
3135 *
3136 * <p> If this class is in a named {@link Module Module} then this method
3137 * will attempt to find the resource in the module. This is done by
3138 * delegating to the module's class loader {@link
3139 * ClassLoader#findResource(String,String) findResource(String,String)}
3140 * method, invoking it with the module name and the absolute name of the
3141 * resource. Resources in named modules are subject to the rules for
3142 * encapsulation specified in the {@code Module} {@link
3143 * Module#getResourceAsStream getResourceAsStream} method and so this
3144 * method returns {@code null} when the resource is a
3145 * non-"{@code .class}" resource in a package that is not open to the
3146 * caller's module.
3147 *
3148 * <p> Otherwise, if this class is not in a named module then the rules for
3149 * searching resources associated with a given class are implemented by the
3150 * defining {@linkplain ClassLoader class loader} of the class. This method
3151 * delegates to this {@code Class} object's class loader.
3152 * If this {@code Class} object was loaded by the bootstrap class loader,
3153 * the method delegates to {@link ClassLoader#getSystemResource}.
3154 *
3155 * <p> Before delegation, an absolute resource name is constructed from the
3156 * given resource name using this algorithm:
3157 *
3158 * <ul>
3159 *
3160 * <li> If the {@code name} begins with a {@code '/'}
3161 * (<code>'\u002f'</code>), then the absolute name of the resource is the
3162 * portion of the {@code name} following the {@code '/'}.
3163 *
3164 * <li> Otherwise, the absolute name is of the following form:
3165 *
3166 * <blockquote>
3167 * {@code modified_package_name/name}
3168 * </blockquote>
3169 *
3170 * <p> Where the {@code modified_package_name} is the package name of this
3171 * object with {@code '/'} substituted for {@code '.'}
3172 * (<code>'\u002e'</code>).
3173 *
3174 * </ul>
3175 *
3176 * @param name name of the desired resource
3177 * @return A {@link java.net.URL} object; {@code null} if no resource with
3178 * this name is found, the resource cannot be located by a URL, the
3179 * resource is in a package that is not
3180 * {@linkplain Module#isOpen(String, Module) open} to at least the caller
3181 * module, or access to the resource is denied by the security
3182 * manager.
3183 * @throws NullPointerException If {@code name} is {@code null}
3184 * @since 1.1
3185 */
3186 @CallerSensitive
3187 public URL getResource(String name) {
3188 name = resolveName(name);
3189
3190 Module thisModule = getModule();
3191 if (thisModule.isNamed()) {
3192 // check if resource can be located by caller
3193 if (Resources.canEncapsulate(name)
3194 && !isOpenToCaller(name, Reflection.getCallerClass())) {
3195 return null;
3196 }
3197
3198 // resource not encapsulated or in package open to caller
3199 String mn = thisModule.getName();
3200 ClassLoader cl = classLoader;
3201 try {
3202 if (cl == null) {
3203 return BootLoader.findResource(mn, name);
3204 } else {
3205 return cl.findResource(mn, name);
3206 }
3207 } catch (IOException ioe) {
3208 return null;
3209 }
3210 }
3211
3212 // unnamed module
3213 ClassLoader cl = classLoader;
3214 if (cl == null) {
3215 return ClassLoader.getSystemResource(name);
3216 } else {
3217 return cl.getResource(name);
3218 }
3219 }
3220
3221 /**
3222 * Returns true if a resource with the given name can be located by the
3223 * given caller. All resources in a module can be located by code in
3224 * the module. For other callers, then the package needs to be open to
3225 * the caller.
3226 */
3227 private boolean isOpenToCaller(String name, Class<?> caller) {
3228 // assert getModule().isNamed();
3229 Module thisModule = getModule();
3230 Module callerModule = (caller != null) ? caller.getModule() : null;
3231 if (callerModule != thisModule) {
3232 String pn = Resources.toPackageName(name);
3233 if (thisModule.getDescriptor().packages().contains(pn)) {
3234 if (callerModule == null) {
3235 // no caller, return true if the package is open to all modules
3236 return thisModule.isOpen(pn);
3237 }
3238 if (!thisModule.isOpen(pn, callerModule)) {
3239 // package not open to caller
3240 return false;
3241 }
3242 }
3243 }
3244 return true;
3245 }
3246
3247 /**
3248 * Returns the {@code ProtectionDomain} of this class. If there is a
3249 * security manager installed, this method first calls the security
3250 * manager's {@code checkPermission} method with a
3251 * {@code RuntimePermission("getProtectionDomain")} permission to
3252 * ensure it's ok to get the
3253 * {@code ProtectionDomain}.
3254 *
3255 * @return the ProtectionDomain of this class
3256 *
3257 * @throws SecurityException
3258 * if a security manager exists and its
3259 * {@code checkPermission} method doesn't allow
3260 * getting the ProtectionDomain.
3261 *
3262 * @see java.security.ProtectionDomain
3263 * @see SecurityManager#checkPermission
3264 * @see java.lang.RuntimePermission
3265 * @since 1.2
3266 */
3267 public ProtectionDomain getProtectionDomain() {
3268 @SuppressWarnings("removal")
3269 SecurityManager sm = System.getSecurityManager();
3270 if (sm != null) {
3271 sm.checkPermission(SecurityConstants.GET_PD_PERMISSION);
3272 }
3273 return protectionDomain();
3274 }
3275
3276 /** Holder for the protection domain returned when the internal domain is null */
3277 private static class Holder {
3278 private static final ProtectionDomain allPermDomain;
3279 static {
3280 Permissions perms = new Permissions();
3281 perms.add(SecurityConstants.ALL_PERMISSION);
3282 allPermDomain = new ProtectionDomain(null, perms);
3283 }
3284 }
3285
3286 // package-private
3287 ProtectionDomain protectionDomain() {
3288 ProtectionDomain pd = getProtectionDomain0();
3289 if (pd == null) {
3290 return Holder.allPermDomain;
3291 } else {
3292 return pd;
3293 }
3294 }
3295
3296 /**
3297 * Returns the ProtectionDomain of this class.
3298 */
3299 private native ProtectionDomain getProtectionDomain0();
3300
3301 /*
3302 * Return the Virtual Machine's Class object for the named
3303 * primitive type.
3304 */
3305 static native Class<?> getPrimitiveClass(String name);
3306
3307 /*
3308 * Check if client is allowed to access members. If access is denied,
3309 * throw a SecurityException.
3310 *
3311 * This method also enforces package access.
3312 *
3313 * <p> Default policy: allow all clients access with normal Java access
3314 * control.
3315 *
3316 * <p> NOTE: should only be called if a SecurityManager is installed
3317 */
3318 private void checkMemberAccess(@SuppressWarnings("removal") SecurityManager sm, int which,
3319 Class<?> caller, boolean checkProxyInterfaces) {
3320 /* Default policy allows access to all {@link Member#PUBLIC} members,
3321 * as well as access to classes that have the same class loader as the caller.
3322 * In all other cases, it requires RuntimePermission("accessDeclaredMembers")
3323 * permission.
3324 */
3325 final ClassLoader ccl = ClassLoader.getClassLoader(caller);
3326 if (which != Member.PUBLIC) {
3327 final ClassLoader cl = classLoader;
3328 if (ccl != cl) {
3329 sm.checkPermission(SecurityConstants.CHECK_MEMBER_ACCESS_PERMISSION);
3330 }
3331 }
3332 this.checkPackageAccess(sm, ccl, checkProxyInterfaces);
3333 }
3334
3335 /*
3336 * Checks if a client loaded in ClassLoader ccl is allowed to access this
3337 * class under the current package access policy. If access is denied,
3338 * throw a SecurityException.
3339 *
3340 * NOTE: this method should only be called if a SecurityManager is active
3341 */
3342 private void checkPackageAccess(@SuppressWarnings("removal") SecurityManager sm, final ClassLoader ccl,
3343 boolean checkProxyInterfaces) {
3344 final ClassLoader cl = classLoader;
3345
3346 if (ReflectUtil.needsPackageAccessCheck(ccl, cl)) {
3347 String pkg = this.getPackageName();
3348 if (!pkg.isEmpty()) {
3349 // skip the package access check on a proxy class in default proxy package
3350 if (!Proxy.isProxyClass(this) || ReflectUtil.isNonPublicProxyClass(this)) {
3351 sm.checkPackageAccess(pkg);
3352 }
3353 }
3354 }
3355 // check package access on the proxy interfaces
3356 if (checkProxyInterfaces && Proxy.isProxyClass(this)) {
3357 ReflectUtil.checkProxyPackageAccess(ccl, this.getInterfaces(/* cloneArray */ false));
3358 }
3359 }
3360
3361 /*
3362 * Checks if a client loaded in ClassLoader ccl is allowed to access the provided
3363 * classes under the current package access policy. If access is denied,
3364 * throw a SecurityException.
3365 *
3366 * NOTE: this method should only be called if a SecurityManager is active
3367 * classes must be non-empty
3368 * all classes provided must be loaded by the same ClassLoader
3369 * NOTE: this method does not support Proxy classes
3370 */
3371 private static void checkPackageAccessForPermittedSubclasses(@SuppressWarnings("removal") SecurityManager sm,
3372 final ClassLoader ccl, Class<?>[] subClasses) {
3373 final ClassLoader cl = subClasses[0].classLoader;
3374
3375 if (ReflectUtil.needsPackageAccessCheck(ccl, cl)) {
3376 Set<String> packages = new HashSet<>();
3377
3378 for (Class<?> c : subClasses) {
3379 if (Proxy.isProxyClass(c))
3380 throw new InternalError("a permitted subclass should not be a proxy class: " + c);
3381 String pkg = c.getPackageName();
3382 if (!pkg.isEmpty()) {
3383 packages.add(pkg);
3384 }
3385 }
3386 for (String pkg : packages) {
3387 sm.checkPackageAccess(pkg);
3388 }
3389 }
3390 }
3391
3392 /**
3393 * Add a package name prefix if the name is not absolute. Remove leading "/"
3394 * if name is absolute
3395 */
3396 private String resolveName(String name) {
3397 if (!name.startsWith("/")) {
3398 String baseName = getPackageName();
3399 if (!baseName.isEmpty()) {
3400 int len = baseName.length() + 1 + name.length();
3401 StringBuilder sb = new StringBuilder(len);
3402 name = sb.append(baseName.replace('.', '/'))
3403 .append('/')
3404 .append(name)
3405 .toString();
3406 }
3407 } else {
3408 name = name.substring(1);
3409 }
3410 return name;
3411 }
3412
3413 /**
3414 * Atomic operations support.
3415 */
3416 private static class Atomic {
3417 // initialize Unsafe machinery here, since we need to call Class.class instance method
3418 // and have to avoid calling it in the static initializer of the Class class...
3419 private static final Unsafe unsafe = Unsafe.getUnsafe();
3420 // offset of Class.reflectionData instance field
3421 private static final long reflectionDataOffset
3422 = unsafe.objectFieldOffset(Class.class, "reflectionData");
3423 // offset of Class.annotationType instance field
3424 private static final long annotationTypeOffset
3425 = unsafe.objectFieldOffset(Class.class, "annotationType");
3426 // offset of Class.annotationData instance field
3427 private static final long annotationDataOffset
3428 = unsafe.objectFieldOffset(Class.class, "annotationData");
3429
3430 static <T> boolean casReflectionData(Class<?> clazz,
3431 ReflectionData<T> oldData,
3432 ReflectionData<T> newData) {
3433 return unsafe.compareAndSetReference(clazz, reflectionDataOffset, oldData, newData);
3434 }
3435
3436 static boolean casAnnotationType(Class<?> clazz,
3437 AnnotationType oldType,
3438 AnnotationType newType) {
3439 return unsafe.compareAndSetReference(clazz, annotationTypeOffset, oldType, newType);
3440 }
3441
3442 static boolean casAnnotationData(Class<?> clazz,
3443 AnnotationData oldData,
3444 AnnotationData newData) {
3445 return unsafe.compareAndSetReference(clazz, annotationDataOffset, oldData, newData);
3446 }
3447 }
3448
3449 /**
3450 * Reflection support.
3451 */
3452
3453 // Reflection data caches various derived names and reflective members. Cached
3454 // values may be invalidated when JVM TI RedefineClasses() is called
3455 private static class ReflectionData<T> {
3456 volatile Field[] declaredFields;
3457 volatile Field[] publicFields;
3458 volatile Method[] declaredMethods;
3459 volatile Method[] publicMethods;
3460 volatile Constructor<T>[] declaredConstructors;
3461 volatile Constructor<T>[] publicConstructors;
3462 // Intermediate results for getFields and getMethods
3463 volatile Field[] declaredPublicFields;
3464 volatile Method[] declaredPublicMethods;
3465 volatile Class<?>[] interfaces;
3466
3467 // Cached names
3468 String simpleName;
3469 String canonicalName;
3470 static final String NULL_SENTINEL = new String();
3471
3472 // Value of classRedefinedCount when we created this ReflectionData instance
3473 final int redefinedCount;
3474
3475 ReflectionData(int redefinedCount) {
3476 this.redefinedCount = redefinedCount;
3477 }
3478 }
3479
3480 private transient volatile ReflectionData<T> reflectionData;
3481
3482 // Incremented by the VM on each call to JVM TI RedefineClasses()
3483 // that redefines this class or a superclass.
3484 private transient volatile int classRedefinedCount;
3485
3486 // Lazily create and cache ReflectionData
3487 private ReflectionData<T> reflectionData() {
3488 ReflectionData<T> reflectionData = this.reflectionData;
3489 int classRedefinedCount = this.classRedefinedCount;
3490 if (reflectionData != null &&
3491 reflectionData.redefinedCount == classRedefinedCount) {
3492 return reflectionData;
3493 }
3494 // else no SoftReference or cleared SoftReference or stale ReflectionData
3495 // -> create and replace new instance
3496 return newReflectionData(reflectionData, classRedefinedCount);
3497 }
3498
3499 private ReflectionData<T> newReflectionData(ReflectionData<T> oldReflectionData,
3500 int classRedefinedCount) {
3501 while (true) {
3502 ReflectionData<T> rd = new ReflectionData<>(classRedefinedCount);
3503 // try to CAS it...
3504 if (Atomic.casReflectionData(this, oldReflectionData, rd)) {
3505 return rd;
3506 }
3507 // else retry
3508 oldReflectionData = this.reflectionData;
3509 classRedefinedCount = this.classRedefinedCount;
3510 if (oldReflectionData != null && oldReflectionData.redefinedCount == classRedefinedCount) {
3511 return rd;
3512 }
3513 }
3514 }
3515
3516 // Generic signature handling
3517 private native String getGenericSignature0();
3518
3519 // Generic info repository; lazily initialized
3520 private transient volatile ClassRepository genericInfo;
3521
3522 // accessor for factory
3523 private GenericsFactory getFactory() {
3524 // create scope and factory
3525 return CoreReflectionFactory.make(this, ClassScope.make(this));
3526 }
3527
3528 // accessor for generic info repository;
3529 // generic info is lazily initialized
3530 private ClassRepository getGenericInfo() {
3531 ClassRepository genericInfo = this.genericInfo;
3532 if (genericInfo == null) {
3533 String signature = getGenericSignature0();
3534 if (signature == null) {
3535 genericInfo = ClassRepository.NONE;
3536 } else {
3537 genericInfo = ClassRepository.make(signature, getFactory());
3538 }
3539 this.genericInfo = genericInfo;
3540 }
3541 return (genericInfo != ClassRepository.NONE) ? genericInfo : null;
3542 }
3543
3544 // Annotations handling
3545 native byte[] getRawAnnotations();
3546 // Since 1.8
3547 native byte[] getRawTypeAnnotations();
3548 static byte[] getExecutableTypeAnnotationBytes(Executable ex) {
3549 return getReflectionFactory().getExecutableTypeAnnotationBytes(ex);
3550 }
3551
3552 native ConstantPool getConstantPool();
3553
3554 //
3555 //
3556 // java.lang.reflect.Field handling
3557 //
3558 //
3559
3560 // Returns an array of "root" fields. These Field objects must NOT
3561 // be propagated to the outside world, but must instead be copied
3562 // via ReflectionFactory.copyField.
3563 private Field[] privateGetDeclaredFields(boolean publicOnly) {
3564 Field[] res;
3565 ReflectionData<T> rd = reflectionData();
3566 if (rd != null) {
3567 res = publicOnly ? rd.declaredPublicFields : rd.declaredFields;
3568 if (res != null) return res;
3569 }
3570 // No cached value available; request value from VM
3571 res = Reflection.filterFields(this, getDeclaredFields0(publicOnly));
3572 if (rd != null) {
3573 if (publicOnly) {
3574 rd.declaredPublicFields = res;
3575 } else {
3576 rd.declaredFields = res;
3577 }
3578 }
3579 return res;
3580 }
3581
3582 // Returns an array of "root" fields. These Field objects must NOT
3583 // be propagated to the outside world, but must instead be copied
3584 // via ReflectionFactory.copyField.
3585 private Field[] privateGetPublicFields() {
3586 Field[] res;
3587 ReflectionData<T> rd = reflectionData();
3588 if (rd != null) {
3589 res = rd.publicFields;
3590 if (res != null) return res;
3591 }
3592
3593 // Use a linked hash set to ensure order is preserved and
3594 // fields from common super interfaces are not duplicated
3595 LinkedHashSet<Field> fields = new LinkedHashSet<>();
3596
3597 // Local fields
3598 addAll(fields, privateGetDeclaredFields(true));
3599
3600 // Direct superinterfaces, recursively
3601 for (Class<?> si : getInterfaces(/* cloneArray */ false)) {
3602 addAll(fields, si.privateGetPublicFields());
3603 }
3604
3605 // Direct superclass, recursively
3606 Class<?> sc = getSuperclass();
3607 if (sc != null) {
3608 addAll(fields, sc.privateGetPublicFields());
3609 }
3610
3611 res = fields.toArray(new Field[0]);
3612 if (rd != null) {
3613 rd.publicFields = res;
3614 }
3615 return res;
3616 }
3617
3618 private static void addAll(Collection<Field> c, Field[] o) {
3619 for (Field f : o) {
3620 c.add(f);
3621 }
3622 }
3623
3624
3625 //
3626 //
3627 // java.lang.reflect.Constructor handling
3628 //
3629 //
3630
3631 // Returns an array of "root" constructors. These Constructor
3632 // objects must NOT be propagated to the outside world, but must
3633 // instead be copied via ReflectionFactory.copyConstructor.
3634 private Constructor<T>[] privateGetDeclaredConstructors(boolean publicOnly) {
3635 Constructor<T>[] res;
3636 ReflectionData<T> rd = reflectionData();
3637 if (rd != null) {
3638 res = publicOnly ? rd.publicConstructors : rd.declaredConstructors;
3639 if (res != null) return res;
3640 }
3641 // No cached value available; request value from VM
3642 if (isInterface()) {
3643 @SuppressWarnings("unchecked")
3644 Constructor<T>[] temporaryRes = (Constructor<T>[]) new Constructor<?>[0];
3645 res = temporaryRes;
3646 } else {
3647 res = getDeclaredConstructors0(publicOnly);
3648 }
3649 if (rd != null) {
3650 if (publicOnly) {
3651 rd.publicConstructors = res;
3652 } else {
3653 rd.declaredConstructors = res;
3654 }
3655 }
3656 return res;
3657 }
3658
3659 //
3660 //
3661 // java.lang.reflect.Method handling
3662 //
3663 //
3664
3665 // Returns an array of "root" methods. These Method objects must NOT
3666 // be propagated to the outside world, but must instead be copied
3667 // via ReflectionFactory.copyMethod.
3668 private Method[] privateGetDeclaredMethods(boolean publicOnly) {
3669 Method[] res;
3670 ReflectionData<T> rd = reflectionData();
3671 if (rd != null) {
3672 res = publicOnly ? rd.declaredPublicMethods : rd.declaredMethods;
3673 if (res != null) return res;
3674 }
3675 // No cached value available; request value from VM
3676 res = Reflection.filterMethods(this, getDeclaredMethods0(publicOnly));
3677 if (rd != null) {
3678 if (publicOnly) {
3679 rd.declaredPublicMethods = res;
3680 } else {
3681 rd.declaredMethods = res;
3682 }
3683 }
3684 return res;
3685 }
3686
3687 // Returns an array of "root" methods. These Method objects must NOT
3688 // be propagated to the outside world, but must instead be copied
3689 // via ReflectionFactory.copyMethod.
3690 private Method[] privateGetPublicMethods() {
3691 Method[] res;
3692 ReflectionData<T> rd = reflectionData();
3693 if (rd != null) {
3694 res = rd.publicMethods;
3695 if (res != null) return res;
3696 }
3697
3698 // No cached value available; compute value recursively.
3699 // Start by fetching public declared methods...
3700 PublicMethods pms = new PublicMethods();
3701 for (Method m : privateGetDeclaredMethods(/* publicOnly */ true)) {
3702 pms.merge(m);
3703 }
3704 // ...then recur over superclass methods...
3705 Class<?> sc = getSuperclass();
3706 if (sc != null) {
3707 for (Method m : sc.privateGetPublicMethods()) {
3708 pms.merge(m);
3709 }
3710 }
3711 // ...and finally over direct superinterfaces.
3712 for (Class<?> intf : getInterfaces(/* cloneArray */ false)) {
3713 for (Method m : intf.privateGetPublicMethods()) {
3714 // static interface methods are not inherited
3715 if (!Modifier.isStatic(m.getModifiers())) {
3716 pms.merge(m);
3717 }
3718 }
3719 }
3720
3721 res = pms.toArray();
3722 if (rd != null) {
3723 rd.publicMethods = res;
3724 }
3725 return res;
3726 }
3727
3728
3729 //
3730 // Helpers for fetchers of one field, method, or constructor
3731 //
3732
3733 // This method does not copy the returned Field object!
3734 private static Field searchFields(Field[] fields, String name) {
3735 for (Field field : fields) {
3736 if (field.getName().equals(name)) {
3737 return field;
3738 }
3739 }
3740 return null;
3741 }
3742
3743 // Returns a "root" Field object. This Field object must NOT
3744 // be propagated to the outside world, but must instead be copied
3745 // via ReflectionFactory.copyField.
3746 private Field getField0(String name) {
3747 // Note: the intent is that the search algorithm this routine
3748 // uses be equivalent to the ordering imposed by
3749 // privateGetPublicFields(). It fetches only the declared
3750 // public fields for each class, however, to reduce the number
3751 // of Field objects which have to be created for the common
3752 // case where the field being requested is declared in the
3753 // class which is being queried.
3754 Field res;
3755 // Search declared public fields
3756 if ((res = searchFields(privateGetDeclaredFields(true), name)) != null) {
3757 return res;
3758 }
3759 // Direct superinterfaces, recursively
3760 Class<?>[] interfaces = getInterfaces(/* cloneArray */ false);
3761 for (Class<?> c : interfaces) {
3762 if ((res = c.getField0(name)) != null) {
3763 return res;
3764 }
3765 }
3766 // Direct superclass, recursively
3767 if (!isInterface()) {
3768 Class<?> c = getSuperclass();
3769 if (c != null) {
3770 if ((res = c.getField0(name)) != null) {
3771 return res;
3772 }
3773 }
3774 }
3775 return null;
3776 }
3777
3778 // This method does not copy the returned Method object!
3779 private static Method searchMethods(Method[] methods,
3780 String name,
3781 Class<?>[] parameterTypes)
3782 {
3783 ReflectionFactory fact = getReflectionFactory();
3784 Method res = null;
3785 for (Method m : methods) {
3786 if (m.getName().equals(name)
3787 && arrayContentsEq(parameterTypes,
3788 fact.getExecutableSharedParameterTypes(m))
3789 && (res == null
3790 || (res.getReturnType() != m.getReturnType()
3791 && res.getReturnType().isAssignableFrom(m.getReturnType()))))
3792 res = m;
3793 }
3794 return res;
3795 }
3796
3797 private static final Class<?>[] EMPTY_CLASS_ARRAY = new Class<?>[0];
3798
3799 // Returns a "root" Method object. This Method object must NOT
3800 // be propagated to the outside world, but must instead be copied
3801 // via ReflectionFactory.copyMethod.
3802 private Method getMethod0(String name, Class<?>[] parameterTypes) {
3803 PublicMethods.MethodList res = getMethodsRecursive(
3804 name,
3805 parameterTypes == null ? EMPTY_CLASS_ARRAY : parameterTypes,
3806 /* includeStatic */ true, /* publicOnly */ true);
3807 return res == null ? null : res.getMostSpecific();
3808 }
3809
3810 // Returns a list of "root" Method objects. These Method objects must NOT
3811 // be propagated to the outside world, but must instead be copied
3812 // via ReflectionFactory.copyMethod.
3813 private PublicMethods.MethodList getMethodsRecursive(String name,
3814 Class<?>[] parameterTypes,
3815 boolean includeStatic,
3816 boolean publicOnly) {
3817 // 1st check declared methods
3818 Method[] methods = privateGetDeclaredMethods(publicOnly);
3819 PublicMethods.MethodList res = PublicMethods.MethodList
3820 .filter(methods, name, parameterTypes, includeStatic);
3821 // if there is at least one match among declared methods, we need not
3822 // search any further as such match surely overrides matching methods
3823 // declared in superclass(es) or interface(s).
3824 if (res != null) {
3825 return res;
3826 }
3827
3828 // if there was no match among declared methods,
3829 // we must consult the superclass (if any) recursively...
3830 Class<?> sc = getSuperclass();
3831 if (sc != null) {
3832 res = sc.getMethodsRecursive(name, parameterTypes, includeStatic, publicOnly);
3833 }
3834
3835 // ...and coalesce the superclass methods with methods obtained
3836 // from directly implemented interfaces excluding static methods...
3837 for (Class<?> intf : getInterfaces(/* cloneArray */ false)) {
3838 res = PublicMethods.MethodList.merge(
3839 res, intf.getMethodsRecursive(name, parameterTypes, /* includeStatic */ false, publicOnly));
3840 }
3841
3842 return res;
3843 }
3844
3845 // Returns a "root" Constructor object. This Constructor object must NOT
3846 // be propagated to the outside world, but must instead be copied
3847 // via ReflectionFactory.copyConstructor.
3848 private Constructor<T> getConstructor0(Class<?>[] parameterTypes,
3849 int which) throws NoSuchMethodException
3850 {
3851 ReflectionFactory fact = getReflectionFactory();
3852 Constructor<T>[] constructors = privateGetDeclaredConstructors((which == Member.PUBLIC));
3853 for (Constructor<T> constructor : constructors) {
3854 if (arrayContentsEq(parameterTypes,
3855 fact.getExecutableSharedParameterTypes(constructor))) {
3856 return constructor;
3857 }
3858 }
3859 throw new NoSuchMethodException(methodToString("<init>", parameterTypes));
3860 }
3861
3862 //
3863 // Other helpers and base implementation
3864 //
3865
3866 private static boolean arrayContentsEq(Object[] a1, Object[] a2) {
3867 if (a1 == null) {
3868 return a2 == null || a2.length == 0;
3869 }
3870
3871 if (a2 == null) {
3872 return a1.length == 0;
3873 }
3874
3875 if (a1.length != a2.length) {
3876 return false;
3877 }
3878
3879 for (int i = 0; i < a1.length; i++) {
3880 if (a1[i] != a2[i]) {
3881 return false;
3882 }
3883 }
3884
3885 return true;
3886 }
3887
3888 private static Field[] copyFields(Field[] arg) {
3889 Field[] out = new Field[arg.length];
3890 ReflectionFactory fact = getReflectionFactory();
3891 for (int i = 0; i < arg.length; i++) {
3892 out[i] = fact.copyField(arg[i]);
3893 }
3894 return out;
3895 }
3896
3897 private static Method[] copyMethods(Method[] arg) {
3898 Method[] out = new Method[arg.length];
3899 ReflectionFactory fact = getReflectionFactory();
3900 for (int i = 0; i < arg.length; i++) {
3901 out[i] = fact.copyMethod(arg[i]);
3902 }
3903 return out;
3904 }
3905
3906 private static <U> Constructor<U>[] copyConstructors(Constructor<U>[] arg) {
3907 Constructor<U>[] out = arg.clone();
3908 ReflectionFactory fact = getReflectionFactory();
3909 for (int i = 0; i < out.length; i++) {
3910 out[i] = fact.copyConstructor(out[i]);
3911 }
3912 return out;
3913 }
3914
3915 private native Field[] getDeclaredFields0(boolean publicOnly);
3916 private native Method[] getDeclaredMethods0(boolean publicOnly);
3917 private native Constructor<T>[] getDeclaredConstructors0(boolean publicOnly);
3918 private native Class<?>[] getDeclaredClasses0();
3919
3920 /*
3921 * Returns an array containing the components of the Record attribute,
3922 * or null if the attribute is not present.
3923 *
3924 * Note that this method returns non-null array on a class with
3925 * the Record attribute even if this class is not a record.
3926 */
3927 private native RecordComponent[] getRecordComponents0();
3928 private native boolean isRecord0();
3929
3930 /**
3931 * Helper method to get the method name from arguments.
3932 */
3933 private String methodToString(String name, Class<?>[] argTypes) {
3934 return getName() + '.' + name +
3935 ((argTypes == null || argTypes.length == 0) ?
3936 "()" :
3937 Arrays.stream(argTypes)
3938 .map(c -> c == null ? "null" : c.getName())
3939 .collect(Collectors.joining(",", "(", ")")));
3940 }
3941
3942 /** use serialVersionUID from JDK 1.1 for interoperability */
3943 @java.io.Serial
3944 private static final long serialVersionUID = 3206093459760846163L;
3945
3946
3947 /**
3948 * Class Class is special cased within the Serialization Stream Protocol.
3949 *
3950 * A Class instance is written initially into an ObjectOutputStream in the
3951 * following format:
3952 * <pre>
3953 * {@code TC_CLASS} ClassDescriptor
3954 * A ClassDescriptor is a special cased serialization of
3955 * a {@code java.io.ObjectStreamClass} instance.
3956 * </pre>
3957 * A new handle is generated for the initial time the class descriptor
3958 * is written into the stream. Future references to the class descriptor
3959 * are written as references to the initial class descriptor instance.
3960 *
3961 * @see java.io.ObjectStreamClass
3962 */
3963 @java.io.Serial
3964 private static final ObjectStreamField[] serialPersistentFields =
3965 new ObjectStreamField[0];
3966
3967
3968 /**
3969 * Returns the assertion status that would be assigned to this
3970 * class if it were to be initialized at the time this method is invoked.
3971 * If this class has had its assertion status set, the most recent
3972 * setting will be returned; otherwise, if any package default assertion
3973 * status pertains to this class, the most recent setting for the most
3974 * specific pertinent package default assertion status is returned;
3975 * otherwise, if this class is not a system class (i.e., it has a
3976 * class loader) its class loader's default assertion status is returned;
3977 * otherwise, the system class default assertion status is returned.
3978 *
3979 * @apiNote
3980 * Few programmers will have any need for this method; it is provided
3981 * for the benefit of the JDK itself. (It allows a class to determine at
3982 * the time that it is initialized whether assertions should be enabled.)
3983 * Note that this method is not guaranteed to return the actual
3984 * assertion status that was (or will be) associated with the specified
3985 * class when it was (or will be) initialized.
3986 *
3987 * @return the desired assertion status of the specified class.
3988 * @see java.lang.ClassLoader#setClassAssertionStatus
3989 * @see java.lang.ClassLoader#setPackageAssertionStatus
3990 * @see java.lang.ClassLoader#setDefaultAssertionStatus
3991 * @since 1.4
3992 */
3993 public boolean desiredAssertionStatus() {
3994 ClassLoader loader = classLoader;
3995 // If the loader is null this is a system class, so ask the VM
3996 if (loader == null)
3997 return desiredAssertionStatus0(this);
3998
3999 // If the classloader has been initialized with the assertion
4000 // directives, ask it. Otherwise, ask the VM.
4001 synchronized(loader.assertionLock) {
4002 if (loader.classAssertionStatus != null) {
4003 return loader.desiredAssertionStatus(getName());
4004 }
4005 }
4006 return desiredAssertionStatus0(this);
4007 }
4008
4009 // Retrieves the desired assertion status of this class from the VM
4010 private static native boolean desiredAssertionStatus0(Class<?> clazz);
4011
4012 /**
4013 * Returns true if and only if this class was declared as an enum in the
4014 * source code.
4015 *
4016 * Note that {@link java.lang.Enum} is not itself an enum class.
4017 *
4018 * Also note that if an enum constant is declared with a class body,
4019 * the class of that enum constant object is an anonymous class
4020 * and <em>not</em> the class of the declaring enum class. The
4021 * {@link Enum#getDeclaringClass} method of an enum constant can
4022 * be used to get the class of the enum class declaring the
4023 * constant.
4024 *
4025 * @return true if and only if this class was declared as an enum in the
4026 * source code
4027 * @since 1.5
4028 * @jls 8.9.1 Enum Constants
4029 */
4030 public boolean isEnum() {
4031 // An enum must both directly extend java.lang.Enum and have
4032 // the ENUM bit set; classes for specialized enum constants
4033 // don't do the former.
4034 return (this.getModifiers() & ENUM) != 0 &&
4035 this.getSuperclass() == java.lang.Enum.class;
4036 }
4037
4038 /**
4039 * Returns {@code true} if and only if this class is a record class.
4040 *
4041 * <p> The {@linkplain #getSuperclass() direct superclass} of a record
4042 * class is {@code java.lang.Record}. A record class is {@linkplain
4043 * Modifier#FINAL final}. A record class has (possibly zero) record
4044 * components; {@link #getRecordComponents()} returns a non-null but
4045 * possibly empty value for a record.
4046 *
4047 * <p> Note that class {@link Record} is not a record class and thus
4048 * invoking this method on class {@code Record} returns {@code false}.
4049 *
4050 * @return true if and only if this class is a record class, otherwise false
4051 * @jls 8.10 Record Classes
4052 * @since 16
4053 */
4054 public boolean isRecord() {
4055 // this superclass and final modifier check is not strictly necessary
4056 // they are intrinsified and serve as a fast-path check
4057 return getSuperclass() == java.lang.Record.class &&
4058 (this.getModifiers() & Modifier.FINAL) != 0 &&
4059 isRecord0();
4060 }
4061
4062 // Fetches the factory for reflective objects
4063 @SuppressWarnings("removal")
4064 private static ReflectionFactory getReflectionFactory() {
4065 var factory = reflectionFactory;
4066 if (factory != null) {
4067 return factory;
4068 }
4069 return reflectionFactory =
4070 java.security.AccessController.doPrivileged
4071 (new ReflectionFactory.GetReflectionFactoryAction());
4072 }
4073 private static ReflectionFactory reflectionFactory;
4074
4075 /**
4076 * Returns the elements of this enum class or null if this
4077 * Class object does not represent an enum class.
4078 *
4079 * @return an array containing the values comprising the enum class
4080 * represented by this {@code Class} object in the order they're
4081 * declared, or null if this {@code Class} object does not
4082 * represent an enum class
4083 * @since 1.5
4084 * @jls 8.9.1 Enum Constants
4085 */
4086 public T[] getEnumConstants() {
4087 T[] values = getEnumConstantsShared();
4088 return (values != null) ? values.clone() : null;
4089 }
4090
4091 /**
4092 * Returns the elements of this enum class or null if this
4093 * Class object does not represent an enum class;
4094 * identical to getEnumConstants except that the result is
4095 * uncloned, cached, and shared by all callers.
4096 */
4097 @SuppressWarnings("removal")
4098 T[] getEnumConstantsShared() {
4099 T[] constants = enumConstants;
4100 if (constants == null) {
4101 if (!isEnum()) return null;
4102 try {
4103 final Method values = getMethod("values");
4104 java.security.AccessController.doPrivileged(
4105 new java.security.PrivilegedAction<>() {
4106 public Void run() {
4107 values.setAccessible(true);
4108 return null;
4109 }
4110 });
4111 @SuppressWarnings("unchecked")
4112 T[] temporaryConstants = (T[])values.invoke(null);
4113 enumConstants = constants = temporaryConstants;
4114 }
4115 // These can happen when users concoct enum-like classes
4116 // that don't comply with the enum spec.
4117 catch (InvocationTargetException | NoSuchMethodException |
4118 IllegalAccessException | NullPointerException |
4119 ClassCastException ex) { return null; }
4120 }
4121 return constants;
4122 }
4123 private transient volatile T[] enumConstants;
4124
4125 /**
4126 * Returns a map from simple name to enum constant. This package-private
4127 * method is used internally by Enum to implement
4128 * {@code public static <T extends Enum<T>> T valueOf(Class<T>, String)}
4129 * efficiently. Note that the map is returned by this method is
4130 * created lazily on first use. Typically it won't ever get created.
4131 */
4132 Map<String, T> enumConstantDirectory() {
4133 Map<String, T> directory = enumConstantDirectory;
4134 if (directory == null) {
4135 T[] universe = getEnumConstantsShared();
4136 if (universe == null)
4137 throw new IllegalArgumentException(
4138 getName() + " is not an enum class");
4139 directory = HashMap.newHashMap(universe.length);
4140 for (T constant : universe) {
4141 directory.put(((Enum<?>)constant).name(), constant);
4142 }
4143 enumConstantDirectory = directory;
4144 }
4145 return directory;
4146 }
4147 private transient volatile Map<String, T> enumConstantDirectory;
4148
4149 /**
4150 * Casts an object to the class or interface represented
4151 * by this {@code Class} object.
4152 *
4153 * @param obj the object to be cast
4154 * @return the object after casting, or null if obj is null
4155 *
4156 * @throws ClassCastException if the object is not
4157 * null and is not assignable to the type T.
4158 *
4159 * @since 1.5
4160 */
4161 @SuppressWarnings("unchecked")
4162 @IntrinsicCandidate
4163 public T cast(Object obj) {
4164 if (obj != null && !isInstance(obj))
4165 throw new ClassCastException(cannotCastMsg(obj));
4166 return (T) obj;
4167 }
4168
4169 private String cannotCastMsg(Object obj) {
4170 return "Cannot cast " + obj.getClass().getName() + " to " + getName();
4171 }
4172
4173 /**
4174 * Casts this {@code Class} object to represent a subclass of the class
4175 * represented by the specified class object. Checks that the cast
4176 * is valid, and throws a {@code ClassCastException} if it is not. If
4177 * this method succeeds, it always returns a reference to this {@code Class} object.
4178 *
4179 * <p>This method is useful when a client needs to "narrow" the type of
4180 * a {@code Class} object to pass it to an API that restricts the
4181 * {@code Class} objects that it is willing to accept. A cast would
4182 * generate a compile-time warning, as the correctness of the cast
4183 * could not be checked at runtime (because generic types are implemented
4184 * by erasure).
4185 *
4186 * @param <U> the type to cast this {@code Class} object to
4187 * @param clazz the class of the type to cast this {@code Class} object to
4188 * @return this {@code Class} object, cast to represent a subclass of
4189 * the specified class object.
4190 * @throws ClassCastException if this {@code Class} object does not
4191 * represent a subclass of the specified class (here "subclass" includes
4192 * the class itself).
4193 * @since 1.5
4194 */
4195 @SuppressWarnings("unchecked")
4196 public <U> Class<? extends U> asSubclass(Class<U> clazz) {
4197 if (clazz.isAssignableFrom(this))
4198 return (Class<? extends U>) this;
4199 else
4200 throw new ClassCastException(this.toString());
4201 }
4202
4203 /**
4204 * {@inheritDoc}
4205 * <p>Note that any annotation returned by this method is a
4206 * declaration annotation.
4207 *
4208 * @throws NullPointerException {@inheritDoc}
4209 * @since 1.5
4210 */
4211 @Override
4212 @SuppressWarnings("unchecked")
4213 public <A extends Annotation> A getAnnotation(Class<A> annotationClass) {
4214 Objects.requireNonNull(annotationClass);
4215
4216 return (A) annotationData().annotations.get(annotationClass);
4217 }
4218
4219 /**
4220 * {@inheritDoc}
4221 * @throws NullPointerException {@inheritDoc}
4222 * @since 1.5
4223 */
4224 @Override
4225 public boolean isAnnotationPresent(Class<? extends Annotation> annotationClass) {
4226 return GenericDeclaration.super.isAnnotationPresent(annotationClass);
4227 }
4228
4229 /**
4230 * {@inheritDoc}
4231 * <p>Note that any annotations returned by this method are
4232 * declaration annotations.
4233 *
4234 * @throws NullPointerException {@inheritDoc}
4235 * @since 1.8
4236 */
4237 @Override
4238 public <A extends Annotation> A[] getAnnotationsByType(Class<A> annotationClass) {
4239 Objects.requireNonNull(annotationClass);
4240
4241 AnnotationData annotationData = annotationData();
4242 return AnnotationSupport.getAssociatedAnnotations(annotationData.declaredAnnotations,
4243 this,
4244 annotationClass);
4245 }
4246
4247 /**
4248 * {@inheritDoc}
4249 * <p>Note that any annotations returned by this method are
4250 * declaration annotations.
4251 *
4252 * @since 1.5
4253 */
4254 @Override
4255 public Annotation[] getAnnotations() {
4256 return AnnotationParser.toArray(annotationData().annotations);
4257 }
4258
4259 /**
4260 * {@inheritDoc}
4261 * <p>Note that any annotation returned by this method is a
4262 * declaration annotation.
4263 *
4264 * @throws NullPointerException {@inheritDoc}
4265 * @since 1.8
4266 */
4267 @Override
4268 @SuppressWarnings("unchecked")
4269 public <A extends Annotation> A getDeclaredAnnotation(Class<A> annotationClass) {
4270 Objects.requireNonNull(annotationClass);
4271
4272 return (A) annotationData().declaredAnnotations.get(annotationClass);
4273 }
4274
4275 /**
4276 * {@inheritDoc}
4277 * <p>Note that any annotations returned by this method are
4278 * declaration annotations.
4279 *
4280 * @throws NullPointerException {@inheritDoc}
4281 * @since 1.8
4282 */
4283 @Override
4284 public <A extends Annotation> A[] getDeclaredAnnotationsByType(Class<A> annotationClass) {
4285 Objects.requireNonNull(annotationClass);
4286
4287 return AnnotationSupport.getDirectlyAndIndirectlyPresent(annotationData().declaredAnnotations,
4288 annotationClass);
4289 }
4290
4291 /**
4292 * {@inheritDoc}
4293 * <p>Note that any annotations returned by this method are
4294 * declaration annotations.
4295 *
4296 * @since 1.5
4297 */
4298 @Override
4299 public Annotation[] getDeclaredAnnotations() {
4300 return AnnotationParser.toArray(annotationData().declaredAnnotations);
4301 }
4302
4303 // annotation data that might get invalidated when JVM TI RedefineClasses() is called
4304 private static class AnnotationData {
4305 final Map<Class<? extends Annotation>, Annotation> annotations;
4306 final Map<Class<? extends Annotation>, Annotation> declaredAnnotations;
4307
4308 // Value of classRedefinedCount when we created this AnnotationData instance
4309 final int redefinedCount;
4310
4311 AnnotationData(Map<Class<? extends Annotation>, Annotation> annotations,
4312 Map<Class<? extends Annotation>, Annotation> declaredAnnotations,
4313 int redefinedCount) {
4314 this.annotations = annotations;
4315 this.declaredAnnotations = declaredAnnotations;
4316 this.redefinedCount = redefinedCount;
4317 }
4318 }
4319
4320 // Annotations cache
4321 @SuppressWarnings("UnusedDeclaration")
4322 private transient volatile AnnotationData annotationData;
4323
4324 private AnnotationData annotationData() {
4325 while (true) { // retry loop
4326 AnnotationData annotationData = this.annotationData;
4327 int classRedefinedCount = this.classRedefinedCount;
4328 if (annotationData != null &&
4329 annotationData.redefinedCount == classRedefinedCount) {
4330 return annotationData;
4331 }
4332 // null or stale annotationData -> optimistically create new instance
4333 AnnotationData newAnnotationData = createAnnotationData(classRedefinedCount);
4334 // try to install it
4335 if (Atomic.casAnnotationData(this, annotationData, newAnnotationData)) {
4336 // successfully installed new AnnotationData
4337 return newAnnotationData;
4338 }
4339 }
4340 }
4341
4342 private AnnotationData createAnnotationData(int classRedefinedCount) {
4343 Map<Class<? extends Annotation>, Annotation> declaredAnnotations =
4344 AnnotationParser.parseAnnotations(getRawAnnotations(), getConstantPool(), this);
4345 Class<?> superClass = getSuperclass();
4346 Map<Class<? extends Annotation>, Annotation> annotations = null;
4347 if (superClass != null) {
4348 Map<Class<? extends Annotation>, Annotation> superAnnotations =
4349 superClass.annotationData().annotations;
4350 for (Map.Entry<Class<? extends Annotation>, Annotation> e : superAnnotations.entrySet()) {
4351 Class<? extends Annotation> annotationClass = e.getKey();
4352 if (AnnotationType.getInstance(annotationClass).isInherited()) {
4353 if (annotations == null) { // lazy construction
4354 annotations = LinkedHashMap.newLinkedHashMap(Math.max(
4355 declaredAnnotations.size(),
4356 Math.min(12, declaredAnnotations.size() + superAnnotations.size())
4357 )
4358 );
4359 }
4360 annotations.put(annotationClass, e.getValue());
4361 }
4362 }
4363 }
4364 if (annotations == null) {
4365 // no inherited annotations -> share the Map with declaredAnnotations
4366 annotations = declaredAnnotations;
4367 } else {
4368 // at least one inherited annotation -> declared may override inherited
4369 annotations.putAll(declaredAnnotations);
4370 }
4371 return new AnnotationData(annotations, declaredAnnotations, classRedefinedCount);
4372 }
4373
4374 // Annotation interfaces cache their internal (AnnotationType) form
4375
4376 @SuppressWarnings("UnusedDeclaration")
4377 private transient volatile AnnotationType annotationType;
4378
4379 boolean casAnnotationType(AnnotationType oldType, AnnotationType newType) {
4380 return Atomic.casAnnotationType(this, oldType, newType);
4381 }
4382
4383 AnnotationType getAnnotationType() {
4384 return annotationType;
4385 }
4386
4387 Map<Class<? extends Annotation>, Annotation> getDeclaredAnnotationMap() {
4388 return annotationData().declaredAnnotations;
4389 }
4390
4391 /* Backing store of user-defined values pertaining to this class.
4392 * Maintained by the ClassValue class.
4393 */
4394 transient ClassValue.ClassValueMap classValueMap;
4395
4396 /**
4397 * Returns an {@code AnnotatedType} object that represents the use of a
4398 * type to specify the superclass of the entity represented by this {@code
4399 * Class} object. (The <em>use</em> of type Foo to specify the superclass
4400 * in '... extends Foo' is distinct from the <em>declaration</em> of class
4401 * Foo.)
4402 *
4403 * <p> If this {@code Class} object represents a class whose declaration
4404 * does not explicitly indicate an annotated superclass, then the return
4405 * value is an {@code AnnotatedType} object representing an element with no
4406 * annotations.
4407 *
4408 * <p> If this {@code Class} represents either the {@code Object} class, an
4409 * interface type, an array type, a primitive type, or void, the return
4410 * value is {@code null}.
4411 *
4412 * @return an object representing the superclass
4413 * @since 1.8
4414 */
4415 public AnnotatedType getAnnotatedSuperclass() {
4416 if (this == Object.class ||
4417 isInterface() ||
4418 isArray() ||
4419 isPrimitive() ||
4420 this == Void.TYPE) {
4421 return null;
4422 }
4423
4424 return TypeAnnotationParser.buildAnnotatedSuperclass(getRawTypeAnnotations(), getConstantPool(), this);
4425 }
4426
4427 /**
4428 * Returns an array of {@code AnnotatedType} objects that represent the use
4429 * of types to specify superinterfaces of the entity represented by this
4430 * {@code Class} object. (The <em>use</em> of type Foo to specify a
4431 * superinterface in '... implements Foo' is distinct from the
4432 * <em>declaration</em> of interface Foo.)
4433 *
4434 * <p> If this {@code Class} object represents a class, the return value is
4435 * an array containing objects representing the uses of interface types to
4436 * specify interfaces implemented by the class. The order of the objects in
4437 * the array corresponds to the order of the interface types used in the
4438 * 'implements' clause of the declaration of this {@code Class} object.
4439 *
4440 * <p> If this {@code Class} object represents an interface, the return
4441 * value is an array containing objects representing the uses of interface
4442 * types to specify interfaces directly extended by the interface. The
4443 * order of the objects in the array corresponds to the order of the
4444 * interface types used in the 'extends' clause of the declaration of this
4445 * {@code Class} object.
4446 *
4447 * <p> If this {@code Class} object represents a class or interface whose
4448 * declaration does not explicitly indicate any annotated superinterfaces,
4449 * the return value is an array of length 0.
4450 *
4451 * <p> If this {@code Class} object represents either the {@code Object}
4452 * class, an array type, a primitive type, or void, the return value is an
4453 * array of length 0.
4454 *
4455 * @return an array representing the superinterfaces
4456 * @since 1.8
4457 */
4458 public AnnotatedType[] getAnnotatedInterfaces() {
4459 return TypeAnnotationParser.buildAnnotatedInterfaces(getRawTypeAnnotations(), getConstantPool(), this);
4460 }
4461
4462 private native Class<?> getNestHost0();
4463
4464 /**
4465 * Returns the nest host of the <a href=#nest>nest</a> to which the class
4466 * or interface represented by this {@code Class} object belongs.
4467 * Every class and interface belongs to exactly one nest.
4468 *
4469 * If the nest host of this class or interface has previously
4470 * been determined, then this method returns the nest host.
4471 * If the nest host of this class or interface has
4472 * not previously been determined, then this method determines the nest
4473 * host using the algorithm of JVMS 5.4.4, and returns it.
4474 *
4475 * Often, a class or interface belongs to a nest consisting only of itself,
4476 * in which case this method returns {@code this} to indicate that the class
4477 * or interface is the nest host.
4478 *
4479 * <p>If this {@code Class} object represents a primitive type, an array type,
4480 * or {@code void}, then this method returns {@code this},
4481 * indicating that the represented entity belongs to the nest consisting only of
4482 * itself, and is the nest host.
4483 *
4484 * @return the nest host of this class or interface
4485 *
4486 * @throws SecurityException
4487 * If the returned class is not the current class, and
4488 * if a security manager, <i>s</i>, is present and the caller's
4489 * class loader is not the same as or an ancestor of the class
4490 * loader for the returned class and invocation of {@link
4491 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
4492 * denies access to the package of the returned class
4493 * @since 11
4494 * @jvms 4.7.28 The {@code NestHost} Attribute
4495 * @jvms 4.7.29 The {@code NestMembers} Attribute
4496 * @jvms 5.4.4 Access Control
4497 */
4498 @CallerSensitive
4499 public Class<?> getNestHost() {
4500 if (isPrimitive() || isArray()) {
4501 return this;
4502 }
4503
4504 Class<?> host = getNestHost0();
4505 if (host == this) {
4506 return this;
4507 }
4508 // returning a different class requires a security check
4509 @SuppressWarnings("removal")
4510 SecurityManager sm = System.getSecurityManager();
4511 if (sm != null) {
4512 checkPackageAccess(sm,
4513 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
4514 }
4515 return host;
4516 }
4517
4518 /**
4519 * Determines if the given {@code Class} is a nestmate of the
4520 * class or interface represented by this {@code Class} object.
4521 * Two classes or interfaces are nestmates
4522 * if they have the same {@linkplain #getNestHost() nest host}.
4523 *
4524 * @param c the class to check
4525 * @return {@code true} if this class and {@code c} are members of
4526 * the same nest; and {@code false} otherwise.
4527 *
4528 * @since 11
4529 */
4530 public boolean isNestmateOf(Class<?> c) {
4531 if (this == c) {
4532 return true;
4533 }
4534 if (isPrimitive() || isArray() ||
4535 c.isPrimitive() || c.isArray()) {
4536 return false;
4537 }
4538
4539 return getNestHost() == c.getNestHost();
4540 }
4541
4542 private native Class<?>[] getNestMembers0();
4543
4544 /**
4545 * Returns an array containing {@code Class} objects representing all the
4546 * classes and interfaces that are members of the nest to which the class
4547 * or interface represented by this {@code Class} object belongs.
4548 *
4549 * First, this method obtains the {@linkplain #getNestHost() nest host},
4550 * {@code H}, of the nest to which the class or interface represented by
4551 * this {@code Class} object belongs. The zeroth element of the returned
4552 * array is {@code H}.
4553 *
4554 * Then, for each class or interface {@code C} which is recorded by {@code H}
4555 * as being a member of its nest, this method attempts to obtain the {@code Class}
4556 * object for {@code C} (using {@linkplain #getClassLoader() the defining class
4557 * loader} of the current {@code Class} object), and then obtains the
4558 * {@linkplain #getNestHost() nest host} of the nest to which {@code C} belongs.
4559 * The classes and interfaces which are recorded by {@code H} as being members
4560 * of its nest, and for which {@code H} can be determined as their nest host,
4561 * are indicated by subsequent elements of the returned array. The order of
4562 * such elements is unspecified. Duplicates are permitted.
4563 *
4564 * <p>If this {@code Class} object represents a primitive type, an array type,
4565 * or {@code void}, then this method returns a single-element array containing
4566 * {@code this}.
4567 *
4568 * @apiNote
4569 * The returned array includes only the nest members recorded in the {@code NestMembers}
4570 * attribute, and not any hidden classes that were added to the nest via
4571 * {@link MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
4572 * Lookup::defineHiddenClass}.
4573 *
4574 * @return an array of all classes and interfaces in the same nest as
4575 * this class or interface
4576 *
4577 * @throws SecurityException
4578 * If any returned class is not the current class, and
4579 * if a security manager, <i>s</i>, is present and the caller's
4580 * class loader is not the same as or an ancestor of the class
4581 * loader for that returned class and invocation of {@link
4582 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
4583 * denies access to the package of that returned class
4584 *
4585 * @since 11
4586 * @see #getNestHost()
4587 * @jvms 4.7.28 The {@code NestHost} Attribute
4588 * @jvms 4.7.29 The {@code NestMembers} Attribute
4589 */
4590 @CallerSensitive
4591 public Class<?>[] getNestMembers() {
4592 if (isPrimitive() || isArray()) {
4593 return new Class<?>[] { this };
4594 }
4595 Class<?>[] members = getNestMembers0();
4596 // Can't actually enable this due to bootstrapping issues
4597 // assert(members.length != 1 || members[0] == this); // expected invariant from VM
4598
4599 if (members.length > 1) {
4600 // If we return anything other than the current class we need
4601 // a security check
4602 @SuppressWarnings("removal")
4603 SecurityManager sm = System.getSecurityManager();
4604 if (sm != null) {
4605 checkPackageAccess(sm,
4606 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
4607 }
4608 }
4609 return members;
4610 }
4611
4612 /**
4613 * Returns the descriptor string of the entity (class, interface, array class,
4614 * primitive type, or {@code void}) represented by this {@code Class} object.
4615 *
4616 * <p> If this {@code Class} object represents a class or interface,
4617 * not an array class, then:
4618 * <ul>
4619 * <li> If the class or interface is not {@linkplain Class#isHidden() hidden},
4620 * then the result is a field descriptor (JVMS {@jvms 4.3.2})
4621 * for the class or interface. Calling
4622 * {@link ClassDesc#ofDescriptor(String) ClassDesc::ofDescriptor}
4623 * with the result descriptor string produces a {@link ClassDesc ClassDesc}
4624 * describing this class or interface.
4625 * <li> If the class or interface is {@linkplain Class#isHidden() hidden},
4626 * then the result is a string of the form:
4627 * <blockquote>
4628 * {@code "L" +} <em>N</em> {@code + "." + <suffix> + ";"}
4629 * </blockquote>
4630 * where <em>N</em> is the {@linkplain ClassLoader##binary-name binary name}
4631 * encoded in internal form indicated by the {@code class} file passed to
4632 * {@link MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
4633 * Lookup::defineHiddenClass}, and {@code <suffix>} is an unqualified name.
4634 * A hidden class or interface has no {@linkplain ClassDesc nominal descriptor}.
4635 * The result string is not a type descriptor.
4636 * </ul>
4637 *
4638 * <p> If this {@code Class} object represents an array class, then
4639 * the result is a string consisting of one or more '{@code [}' characters
4640 * representing the depth of the array nesting, followed by the
4641 * descriptor string of the element type.
4642 * <ul>
4643 * <li> If the element type is not a {@linkplain Class#isHidden() hidden} class
4644 * or interface, then this array class can be described nominally.
4645 * Calling {@link ClassDesc#ofDescriptor(String) ClassDesc::ofDescriptor}
4646 * with the result descriptor string produces a {@link ClassDesc ClassDesc}
4647 * describing this array class.
4648 * <li> If the element type is a {@linkplain Class#isHidden() hidden} class or
4649 * interface, then this array class cannot be described nominally.
4650 * The result string is not a type descriptor.
4651 * </ul>
4652 *
4653 * <p> If this {@code Class} object represents a primitive type or
4654 * {@code void}, then the result is a field descriptor string which
4655 * is a one-letter code corresponding to a primitive type or {@code void}
4656 * ({@code "B", "C", "D", "F", "I", "J", "S", "Z", "V"}) (JVMS {@jvms 4.3.2}).
4657 *
4658 * @return the descriptor string for this {@code Class} object
4659 * @jvms 4.3.2 Field Descriptors
4660 * @since 12
4661 */
4662 @Override
4663 public String descriptorString() {
4664 if (isPrimitive())
4665 return Wrapper.forPrimitiveType(this).basicTypeString();
4666
4667 if (isArray()) {
4668 return "[".concat(componentType.descriptorString());
4669 } else if (isHidden()) {
4670 String name = getName();
4671 int index = name.indexOf('/');
4672 return new StringBuilder(name.length() + 2)
4673 .append('L')
4674 .append(name.substring(0, index).replace('.', '/'))
4675 .append('.')
4676 .append(name, index + 1, name.length())
4677 .append(';')
4678 .toString();
4679 } else {
4680 String name = getName().replace('.', '/');
4681 return StringConcatHelper.concat("L", name, ";");
4682 }
4683 }
4684
4685 /**
4686 * Returns the component type of this {@code Class}, if it describes
4687 * an array type, or {@code null} otherwise.
4688 *
4689 * @implSpec
4690 * Equivalent to {@link Class#getComponentType()}.
4691 *
4692 * @return a {@code Class} describing the component type, or {@code null}
4693 * if this {@code Class} does not describe an array type
4694 * @since 12
4695 */
4696 @Override
4697 public Class<?> componentType() {
4698 return isArray() ? componentType : null;
4699 }
4700
4701 /**
4702 * Returns a {@code Class} for an array type whose component type
4703 * is described by this {@linkplain Class}.
4704 *
4705 * @throws UnsupportedOperationException if this component type is {@linkplain
4706 * Void#TYPE void} or if the number of dimensions of the resulting array
4707 * type would exceed 255.
4708 * @return a {@code Class} describing the array type
4709 * @jvms 4.3.2 Field Descriptors
4710 * @jvms 4.4.1 The {@code CONSTANT_Class_info} Structure
4711 * @since 12
4712 */
4713 @Override
4714 public Class<?> arrayType() {
4715 try {
4716 return Array.newInstance(this, 0).getClass();
4717 } catch (IllegalArgumentException iae) {
4718 throw new UnsupportedOperationException(iae);
4719 }
4720 }
4721
4722 /**
4723 * Returns a nominal descriptor for this instance, if one can be
4724 * constructed, or an empty {@link Optional} if one cannot be.
4725 *
4726 * @return An {@link Optional} containing the resulting nominal descriptor,
4727 * or an empty {@link Optional} if one cannot be constructed.
4728 * @since 12
4729 */
4730 @Override
4731 public Optional<ClassDesc> describeConstable() {
4732 Class<?> c = isArray() ? elementType() : this;
4733 return c.isHidden() ? Optional.empty()
4734 : Optional.of(ConstantUtils.classDesc(this));
4735 }
4736
4737 /**
4738 * Returns {@code true} if and only if the underlying class is a hidden class.
4739 *
4740 * @return {@code true} if and only if this class is a hidden class.
4741 *
4742 * @since 15
4743 * @see MethodHandles.Lookup#defineHiddenClass
4744 * @see Class##hiddenClasses Hidden Classes
4745 */
4746 @IntrinsicCandidate
4747 public native boolean isHidden();
4748
4749 /**
4750 * Returns an array containing {@code Class} objects representing the
4751 * direct subinterfaces or subclasses permitted to extend or
4752 * implement this class or interface if it is sealed. The order of such elements
4753 * is unspecified. The array is empty if this sealed class or interface has no
4754 * permitted subclass. If this {@code Class} object represents a primitive type,
4755 * {@code void}, an array type, or a class or interface that is not sealed,
4756 * that is {@link #isSealed()} returns {@code false}, then this method returns {@code null}.
4757 * Conversely, if {@link #isSealed()} returns {@code true}, then this method
4758 * returns a non-null value.
4759 *
4760 * For each class or interface {@code C} which is recorded as a permitted
4761 * direct subinterface or subclass of this class or interface,
4762 * this method attempts to obtain the {@code Class}
4763 * object for {@code C} (using {@linkplain #getClassLoader() the defining class
4764 * loader} of the current {@code Class} object).
4765 * The {@code Class} objects which can be obtained and which are direct
4766 * subinterfaces or subclasses of this class or interface,
4767 * are indicated by elements of the returned array. If a {@code Class} object
4768 * cannot be obtained, it is silently ignored, and not included in the result
4769 * array.
4770 *
4771 * @return an array of {@code Class} objects of the permitted subclasses of this class or interface,
4772 * or {@code null} if this class or interface is not sealed.
4773 *
4774 * @throws SecurityException
4775 * If a security manager, <i>s</i>, is present and the caller's
4776 * class loader is not the same as or an ancestor of the class
4777 * loader for that returned class and invocation of {@link
4778 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
4779 * denies access to the package of any class in the returned array.
4780 *
4781 * @jls 8.1 Class Declarations
4782 * @jls 9.1 Interface Declarations
4783 * @since 17
4784 */
4785 @CallerSensitive
4786 public Class<?>[] getPermittedSubclasses() {
4787 Class<?>[] subClasses;
4788 if (isArray() || isPrimitive() || (subClasses = getPermittedSubclasses0()) == null) {
4789 return null;
4790 }
4791 if (subClasses.length > 0) {
4792 if (Arrays.stream(subClasses).anyMatch(c -> !isDirectSubType(c))) {
4793 subClasses = Arrays.stream(subClasses)
4794 .filter(this::isDirectSubType)
4795 .toArray(s -> new Class<?>[s]);
4796 }
4797 }
4798 if (subClasses.length > 0) {
4799 // If we return some classes we need a security check:
4800 @SuppressWarnings("removal")
4801 SecurityManager sm = System.getSecurityManager();
4802 if (sm != null) {
4803 checkPackageAccessForPermittedSubclasses(sm,
4804 ClassLoader.getClassLoader(Reflection.getCallerClass()),
4805 subClasses);
4806 }
4807 }
4808 return subClasses;
4809 }
4810
4811 private boolean isDirectSubType(Class<?> c) {
4812 if (isInterface()) {
4813 for (Class<?> i : c.getInterfaces(/* cloneArray */ false)) {
4814 if (i == this) {
4815 return true;
4816 }
4817 }
4818 } else {
4819 return c.getSuperclass() == this;
4820 }
4821 return false;
4822 }
4823
4824 /**
4825 * Returns {@code true} if and only if this {@code Class} object represents
4826 * a sealed class or interface. If this {@code Class} object represents a
4827 * primitive type, {@code void}, or an array type, this method returns
4828 * {@code false}. A sealed class or interface has (possibly zero) permitted
4829 * subclasses; {@link #getPermittedSubclasses()} returns a non-null but
4830 * possibly empty value for a sealed class or interface.
4831 *
4832 * @return {@code true} if and only if this {@code Class} object represents
4833 * a sealed class or interface.
4834 *
4835 * @jls 8.1 Class Declarations
4836 * @jls 9.1 Interface Declarations
4837 * @since 17
4838 */
4839 public boolean isSealed() {
4840 if (isArray() || isPrimitive()) {
4841 return false;
4842 }
4843 return getPermittedSubclasses() != null;
4844 }
4845
4846 private native Class<?>[] getPermittedSubclasses0();
4847
4848 /*
4849 * Return the class's major and minor class file version packed into an int.
4850 * The high order 16 bits contain the class's minor version. The low order
4851 * 16 bits contain the class's major version.
4852 *
4853 * If the class is an array type then the class file version of its element
4854 * type is returned. If the class is a primitive type then the latest class
4855 * file major version is returned and zero is returned for the minor version.
4856 */
4857 private int getClassFileVersion() {
4858 Class<?> c = isArray() ? elementType() : this;
4859 return c.getClassFileVersion0();
4860 }
4861
4862 private native int getClassFileVersion0();
4863
4864 /*
4865 * Return the access flags as they were in the class's bytecode, including
4866 * the original setting of ACC_SUPER.
4867 *
4868 * If the class is an array type then the access flags of the element type is
4869 * returned. If the class is a primitive then ACC_ABSTRACT | ACC_FINAL | ACC_PUBLIC.
4870 */
4871 private int getClassAccessFlagsRaw() {
4872 Class<?> c = isArray() ? elementType() : this;
4873 return c.getClassAccessFlagsRaw0();
4874 }
4875
4876 private native int getClassAccessFlagsRaw0();
4877
4878 // Support for "OLD" CDS workflow -- {
4879 private static final int RD_PUBLIC_METHODS = (1 << 0);
4880 private static final int RD_PUBLIC_FIELDS = (1 << 1);
4881 private static final int RD_DECLARED_CTORS = (1 << 2);
4882 private static final int RD_PUBLIC_CTORS = (1 << 3);
4883 private static final int RD_DECLARED_METHODS = (1 << 4);
4884 private static final int RD_DECLARED_PUBLIC_METHODS = (1 << 5);
4885 private static final int RD_DECLARED_FIELDS = (1 << 6);
4886 private static final int RD_DECLARED_PUBLIC_FIELDS = (1 << 7);
4887 private static final int RD_DECLARED_INTERFACES = (1 << 8);
4888 private static final int RD_DECLARED_SIMPLE_NAME = (1 << 9);
4889 private static final int RD_DECLARED_CANONICAL_NAME = (1 << 10);
4890 private static final int CLS_NAME = (1 << 10);
4891
4892
4893 private int encodeReflectionData() {
4894 int flags = CLS_NAME;
4895 if (reflectionData != null) {
4896 flags = (reflectionData.publicMethods != null ? RD_PUBLIC_METHODS : 0) |
4897 (reflectionData.publicFields != null ? RD_PUBLIC_FIELDS : 0) |
4898 (reflectionData.declaredConstructors != null ? RD_DECLARED_CTORS : 0) |
4899 (reflectionData.publicConstructors != null ? RD_PUBLIC_CTORS : 0) |
4900 (reflectionData.declaredMethods != null ? RD_DECLARED_METHODS : 0) |
4901 (reflectionData.declaredPublicMethods != null ? RD_DECLARED_PUBLIC_METHODS : 0) |
4902 (reflectionData.declaredFields != null ? RD_DECLARED_FIELDS : 0) |
4903 (reflectionData.declaredPublicFields != null ? RD_DECLARED_PUBLIC_FIELDS : 0) |
4904 (reflectionData.interfaces != null ? RD_DECLARED_INTERFACES : 0) |
4905 (reflectionData.simpleName != null ? RD_DECLARED_SIMPLE_NAME : 0) |
4906 (reflectionData.canonicalName != null ? RD_DECLARED_CANONICAL_NAME : 0);
4907 }
4908 return flags;
4909 }
4910 private void generateReflectionData(int flags) {
4911 if ((flags & CLS_NAME ) != 0) { getName(); } // String name
4912 if ((flags & RD_PUBLIC_METHODS ) != 0) { privateGetPublicMethods(); } // Method[] publicMethods;
4913 if ((flags & RD_PUBLIC_FIELDS ) != 0) { privateGetPublicFields(); } // Field[] publicFields;
4914 if ((flags & RD_DECLARED_CTORS ) != 0) { privateGetDeclaredConstructors(false); } // Constructor<T>[] declaredConstructors;
4915 if ((flags & RD_PUBLIC_CTORS ) != 0) { privateGetDeclaredConstructors(true); } // Constructor<T>[] publicConstructors;
4916 if ((flags & RD_DECLARED_METHODS ) != 0) { privateGetDeclaredMethods(false); } // Method[] declaredMethods;
4917 if ((flags & RD_DECLARED_PUBLIC_METHODS) != 0) { privateGetDeclaredMethods(true); } // Method[] declaredPublicMethods;
4918 if ((flags & RD_DECLARED_FIELDS ) != 0) { privateGetDeclaredFields(false); } // Field[] declaredFields;
4919 if ((flags & RD_DECLARED_PUBLIC_FIELDS ) != 0) { privateGetDeclaredFields(true); } // Field[] declaredPublicFields;
4920 if ((flags & RD_DECLARED_INTERFACES ) != 0) { getInterfaces(false); } // Class<?>[] interfaces;
4921 if ((flags & RD_DECLARED_SIMPLE_NAME ) != 0) { getSimpleName(); } // String simpleName;
4922 if ((flags & RD_DECLARED_CANONICAL_NAME) != 0) { getCanonicalName(); } // String canonicalName;
4923 }
4924
4925 // -- }
4926 }