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