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