1 /*
2 * Copyright (c) 1994, 2022, 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.invoke.TypeDescriptor;
31 import java.lang.invoke.MethodHandles;
32 import java.lang.module.ModuleReader;
33 import java.lang.ref.SoftReference;
34 import java.io.IOException;
35 import java.io.InputStream;
36 import java.io.ObjectStreamField;
37 import java.lang.reflect.AnnotatedElement;
38 import java.lang.reflect.AnnotatedType;
39 import java.lang.reflect.Array;
40 import java.lang.reflect.Constructor;
41 import java.lang.reflect.Executable;
42 import java.lang.reflect.Field;
43 import java.lang.reflect.GenericArrayType;
44 import java.lang.reflect.GenericDeclaration;
45 import java.lang.reflect.InvocationTargetException;
46 import java.lang.reflect.Member;
47 import java.lang.reflect.Method;
48 import java.lang.reflect.Modifier;
49 import java.lang.reflect.Proxy;
50 import java.lang.reflect.RecordComponent;
51 import java.lang.reflect.Type;
52 import java.lang.reflect.TypeVariable;
53 import java.lang.constant.Constable;
54 import java.net.URL;
55 import java.security.AccessController;
56 import java.security.PrivilegedAction;
57 import java.util.ArrayList;
58 import java.util.Arrays;
59 import java.util.Collection;
60 import java.util.HashMap;
61 import java.util.HashSet;
62 import java.util.LinkedHashMap;
63 import java.util.LinkedHashSet;
64 import java.util.List;
65 import java.util.Map;
66 import java.util.Objects;
67 import java.util.Optional;
68 import java.util.Set;
69 import java.util.stream.Collectors;
70
71 import jdk.internal.loader.BootLoader;
72 import jdk.internal.loader.BuiltinClassLoader;
73 import jdk.internal.misc.Unsafe;
74 import jdk.internal.module.Resources;
75 import jdk.internal.reflect.CallerSensitive;
76 import jdk.internal.reflect.CallerSensitiveAdapter;
77 import jdk.internal.reflect.ConstantPool;
78 import jdk.internal.reflect.Reflection;
79 import jdk.internal.reflect.ReflectionFactory;
80 import jdk.internal.vm.annotation.ForceInline;
81 import jdk.internal.vm.annotation.IntrinsicCandidate;
82 import sun.invoke.util.Wrapper;
83 import sun.reflect.generics.factory.CoreReflectionFactory;
84 import sun.reflect.generics.factory.GenericsFactory;
85 import sun.reflect.generics.repository.ClassRepository;
86 import sun.reflect.generics.repository.MethodRepository;
87 import sun.reflect.generics.repository.ConstructorRepository;
88 import sun.reflect.generics.scope.ClassScope;
89 import sun.security.util.SecurityConstants;
90 import sun.reflect.annotation.*;
91 import sun.reflect.misc.ReflectUtil;
92
93 /**
94 * Instances of the class {@code Class} represent classes and
95 * interfaces in a running Java application. An enum class and a record
96 * class are kinds of class; an annotation interface is a kind of
97 * interface. Every array also belongs to a class that is reflected as
98 * a {@code Class} object that is shared by all arrays with the same
99 * element type and number of dimensions. The primitive Java types
100 * ({@code boolean}, {@code byte}, {@code char}, {@code short}, {@code
101 * int}, {@code long}, {@code float}, and {@code double}), and the
102 * keyword {@code void} are also represented as {@code Class} objects.
103 *
104 * <p> {@code Class} has no public constructor. Instead a {@code Class}
105 * object is constructed automatically by the Java Virtual Machine when
106 * a class is derived from the bytes of a {@code class} file through
107 * the invocation of one of the following methods:
108 * <ul>
109 * <li> {@link ClassLoader#defineClass(String, byte[], int, int) ClassLoader::defineClass}
110 * <li> {@link java.lang.invoke.MethodHandles.Lookup#defineClass(byte[])
111 * java.lang.invoke.MethodHandles.Lookup::defineClass}
112 * <li> {@link java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
113 * java.lang.invoke.MethodHandles.Lookup::defineHiddenClass}
114 * </ul>
115 *
116 * <p> The methods of class {@code Class} expose many characteristics of a
117 * class or interface. Most characteristics are derived from the {@code class}
118 * file that the class loader passed to the Java Virtual Machine or
119 * from the {@code class} file passed to {@code Lookup::defineClass}
120 * or {@code Lookup::defineHiddenClass}.
121 * A few characteristics are determined by the class loading environment
122 * at run time, such as the module returned by {@link #getModule() getModule()}.
123 *
124 * <p> The following example uses a {@code Class} object to print the
125 * class name of an object:
126 *
127 * <blockquote><pre>
128 * void printClassName(Object obj) {
129 * System.out.println("The class of " + obj +
130 * " is " + obj.getClass().getName());
131 * }
132 * </pre></blockquote>
133 *
134 * It is also possible to get the {@code Class} object for a named
135 * class or interface (or for {@code void}) using a <i>class literal</i>.
136 * For example:
137 *
138 * <blockquote>
139 * {@code System.out.println("The name of class Foo is: "+Foo.class.getName());}
140 * </blockquote>
141 *
142 * <p> Some methods of class {@code Class} expose whether the declaration of
143 * a class or interface in Java source code was <em>enclosed</em> within
144 * another declaration. Other methods describe how a class or interface
145 * is situated in a <em>nest</em>. A <a id="nest">nest</a> is a set of
146 * classes and interfaces, in the same run-time package, that
147 * allow mutual access to their {@code private} members.
148 * The classes and interfaces are known as <em>nestmates</em>.
149 * One nestmate acts as the
150 * <em>nest host</em>, and enumerates the other nestmates which
151 * belong to the nest; each of them in turn records it as the nest host.
152 * The classes and interfaces which belong to a nest, including its host, are
153 * determined when
154 * {@code class} files are generated, for example, a Java compiler
155 * will typically record a top-level class as the host of a nest where the
156 * other members are the classes and interfaces whose declarations are
157 * enclosed within the top-level class declaration.
158 *
159 * <p> A class or interface created by the invocation of
160 * {@link java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
161 * Lookup::defineHiddenClass} is a {@linkplain Class#isHidden() <em>hidden</em>}
162 * class or interface.
163 * All kinds of class, including enum classes and record classes, may be
164 * hidden classes; all kinds of interface, including annotation interfaces,
165 * may be hidden interfaces.
166 *
167 * The {@linkplain #getName() name of a hidden class or interface} is
168 * not a <a href="ClassLoader.html#binary-name">binary name</a>,
169 * which means the following:
170 * <ul>
171 * <li>A hidden class or interface cannot be referenced by the constant pools
172 * of other classes and interfaces.
173 * <li>A hidden class or interface cannot be described in
174 * {@linkplain java.lang.constant.ConstantDesc <em>nominal form</em>} by
175 * {@link #describeConstable() Class::describeConstable},
176 * {@link ClassDesc#of(String) ClassDesc::of}, or
177 * {@link ClassDesc#ofDescriptor(String) ClassDesc::ofDescriptor}.
178 * <li>A hidden class or interface cannot be discovered by {@link #forName Class::forName}
179 * or {@link ClassLoader#loadClass(String, boolean) ClassLoader::loadClass}.
180 * </ul>
181 *
182 * A hidden class or interface is never an array class, but may be
183 * the element type of an array. In all other respects, the fact that
184 * a class or interface is hidden has no bearing on the characteristics
185 * exposed by the methods of class {@code Class}.
186 *
187 * @param <T> the type of the class modeled by this {@code Class}
188 * object. For example, the type of {@code String.class} is {@code
189 * Class<String>}. Use {@code Class<?>} if the class being modeled is
190 * unknown.
191 *
192 * @see java.lang.ClassLoader#defineClass(byte[], int, int)
193 * @since 1.0
194 * @jls 15.8.2 Class Literals
195 */
196 public final class Class<T> implements java.io.Serializable,
197 GenericDeclaration,
198 Type,
199 AnnotatedElement,
200 TypeDescriptor.OfField<Class<?>>,
201 Constable {
202 private static final int ANNOTATION= 0x00002000;
203 private static final int ENUM = 0x00004000;
204 private static final int SYNTHETIC = 0x00001000;
205
206 private static native void registerNatives();
207 static {
208 registerNatives();
209 }
210
211 /*
212 * Private constructor. Only the Java Virtual Machine creates Class objects.
213 * This constructor is not used and prevents the default constructor being
214 * generated.
215 */
216 private Class(ClassLoader loader, Class<?> arrayComponentType) {
217 // Initialize final field for classLoader. The initialization value of non-null
218 // prevents future JIT optimizations from assuming this final field is null.
219 classLoader = loader;
220 componentType = arrayComponentType;
221 }
222
223 /**
224 * Converts the object to a string. The string representation is the
225 * string "class" or "interface", followed by a space, and then by the
226 * name of the class in the format returned by {@code getName}.
227 * If this {@code Class} object represents a primitive type,
228 * this method returns the name of the primitive type. If
229 * this {@code Class} object represents void this method returns
230 * "void". If this {@code Class} object represents an array type,
231 * this method returns "class " followed by {@code getName}.
232 *
233 * @return a string representation of this {@code Class} object.
234 */
235 public String toString() {
236 String kind = isInterface() ? "interface " : isPrimitive() ? "" : "class ";
237 return kind.concat(getName());
238 }
239
240 /**
241 * Returns a string describing this {@code Class}, including
242 * information about modifiers and type parameters.
243 *
244 * The string is formatted as a list of type modifiers, if any,
245 * followed by the kind of type (empty string for primitive types
246 * and {@code class}, {@code enum}, {@code interface},
247 * {@code @interface}, or {@code record} as appropriate), followed
248 * by the type's name, followed by an angle-bracketed
249 * comma-separated list of the type's type parameters, if any,
250 * including informative bounds on the type parameters, if any.
251 *
252 * A space is used to separate modifiers from one another and to
253 * separate any modifiers from the kind of type. The modifiers
254 * occur in canonical order. If there are no type parameters, the
255 * type parameter list is elided.
256 *
257 * For an array type, the string starts with the type name,
258 * followed by an angle-bracketed comma-separated list of the
259 * type's type parameters, if any, followed by a sequence of
260 * {@code []} characters, one set of brackets per dimension of
261 * the array.
262 *
263 * <p>Note that since information about the runtime representation
264 * of a type is being generated, modifiers not present on the
265 * originating source code or illegal on the originating source
266 * code may be present.
267 *
268 * @return a string describing this {@code Class}, including
269 * information about modifiers and type parameters
270 *
271 * @since 1.8
272 */
273 public String toGenericString() {
274 if (isPrimitive()) {
275 return toString();
276 } else {
277 StringBuilder sb = new StringBuilder();
278 Class<?> component = this;
279 int arrayDepth = 0;
280
281 if (isArray()) {
282 do {
283 arrayDepth++;
284 component = component.getComponentType();
285 } while (component.isArray());
286 sb.append(component.getName());
287 } else {
288 // Class modifiers are a superset of interface modifiers
289 int modifiers = getModifiers() & Modifier.classModifiers();
290 if (modifiers != 0) {
291 sb.append(Modifier.toString(modifiers));
292 sb.append(' ');
293 }
294
295 if (isAnnotation()) {
296 sb.append('@');
297 }
298 if (isInterface()) { // Note: all annotation interfaces are interfaces
299 sb.append("interface");
300 } else {
301 if (isEnum())
302 sb.append("enum");
303 else if (isRecord())
304 sb.append("record");
305 else
306 sb.append("class");
307 }
308 sb.append(' ');
309 sb.append(getName());
310 }
311
312 TypeVariable<?>[] typeparms = component.getTypeParameters();
313 if (typeparms.length > 0) {
314 sb.append(Arrays.stream(typeparms)
315 .map(Class::typeVarBounds)
316 .collect(Collectors.joining(",", "<", ">")));
317 }
318
319 if (arrayDepth > 0) sb.append("[]".repeat(arrayDepth));
320
321 return sb.toString();
322 }
323 }
324
325 static String typeVarBounds(TypeVariable<?> typeVar) {
326 Type[] bounds = typeVar.getBounds();
327 if (bounds.length == 1 && bounds[0].equals(Object.class)) {
328 return typeVar.getName();
329 } else {
330 return typeVar.getName() + " extends " +
331 Arrays.stream(bounds)
332 .map(Type::getTypeName)
333 .collect(Collectors.joining(" & "));
334 }
335 }
336
337 /**
338 * Returns the {@code Class} object associated with the class or
339 * interface with the given string name. Invoking this method is
340 * equivalent to:
341 *
342 * <blockquote>
343 * {@code Class.forName(className, true, currentLoader)}
344 * </blockquote>
345 *
346 * where {@code currentLoader} denotes the defining class loader of
347 * the current class.
348 *
349 * <p> For example, the following code fragment returns the
350 * runtime {@code Class} descriptor for the class named
351 * {@code java.lang.Thread}:
352 *
353 * <blockquote>
354 * {@code Class t = Class.forName("java.lang.Thread")}
355 * </blockquote>
356 * <p>
357 * A call to {@code forName("X")} causes the class named
358 * {@code X} to be initialized.
359 *
360 * @param className the fully qualified name of the desired class.
361 * @return the {@code Class} object for the class with the
362 * specified name.
363 * @throws LinkageError if the linkage fails
364 * @throws ExceptionInInitializerError if the initialization provoked
365 * by this method fails
366 * @throws ClassNotFoundException if the class cannot be located
367 *
368 * @jls 12.2 Loading of Classes and Interfaces
369 * @jls 12.3 Linking of Classes and Interfaces
370 * @jls 12.4 Initialization of Classes and Interfaces
371 */
372 @CallerSensitive
373 public static Class<?> forName(String className)
374 throws ClassNotFoundException {
375 Class<?> caller = Reflection.getCallerClass();
376 return forName(className, caller);
377 }
378
379 // Caller-sensitive adapter method for reflective invocation
380 @CallerSensitiveAdapter
381 private static Class<?> forName(String className, Class<?> caller)
382 throws ClassNotFoundException {
383 return forName0(className, true, ClassLoader.getClassLoader(caller), caller);
384 }
385
386 /**
387 * Returns the {@code Class} object associated with the class or
388 * interface with the given string name, using the given class loader.
389 * Given the fully qualified name for a class or interface (in the same
390 * format returned by {@code getName}) this method attempts to
391 * locate and load the class or interface. The specified class
392 * loader is used to load the class or interface. If the parameter
393 * {@code loader} is null, the class is loaded through the bootstrap
394 * class loader. The class is initialized only if the
395 * {@code initialize} parameter is {@code true} and if it has
396 * not been initialized earlier.
397 *
398 * <p> If {@code name} denotes a primitive type or void, an attempt
399 * will be made to locate a user-defined class in the unnamed package whose
400 * name is {@code name}. Therefore, this method cannot be used to
401 * obtain any of the {@code Class} objects representing primitive
402 * types or void.
403 *
404 * <p> If {@code name} denotes an array class, the component type of
405 * the array class is loaded but not initialized.
406 *
407 * <p> For example, in an instance method the expression:
408 *
409 * <blockquote>
410 * {@code Class.forName("Foo")}
411 * </blockquote>
412 *
413 * is equivalent to:
414 *
415 * <blockquote>
416 * {@code Class.forName("Foo", true, this.getClass().getClassLoader())}
417 * </blockquote>
418 *
419 * Note that this method throws errors related to loading, linking
420 * or initializing as specified in Sections {@jls 12.2}, {@jls
421 * 12.3}, and {@jls 12.4} of <cite>The Java Language
422 * Specification</cite>.
423 * Note that this method does not check whether the requested class
424 * is accessible to its caller.
425 *
426 * @param name fully qualified name of the desired class
427
428 * @param initialize if {@code true} the class will be initialized
429 * (which implies linking). See Section {@jls
430 * 12.4} of <cite>The Java Language
431 * Specification</cite>.
432 * @param loader class loader from which the class must be loaded
433 * @return class object representing the desired class
434 *
435 * @throws LinkageError if the linkage fails
436 * @throws ExceptionInInitializerError if the initialization provoked
437 * by this method fails
438 * @throws ClassNotFoundException if the class cannot be located by
439 * the specified class loader
440 * @throws SecurityException
441 * if a security manager is present, and the {@code loader} is
442 * {@code null}, and the caller's class loader is not
443 * {@code null}, and the caller does not have the
444 * {@link RuntimePermission}{@code ("getClassLoader")}
445 *
446 * @see java.lang.Class#forName(String)
447 * @see java.lang.ClassLoader
448 *
449 * @jls 12.2 Loading of Classes and Interfaces
450 * @jls 12.3 Linking of Classes and Interfaces
451 * @jls 12.4 Initialization of Classes and Interfaces
452 * @since 1.2
453 */
454 @CallerSensitive
455 public static Class<?> forName(String name, boolean initialize,
456 ClassLoader loader)
457 throws ClassNotFoundException
458 {
459 Class<?> caller = null;
460 @SuppressWarnings("removal")
461 SecurityManager sm = System.getSecurityManager();
462 if (sm != null) {
463 // Reflective call to get caller class is only needed if a security manager
464 // is present. Avoid the overhead of making this call otherwise.
465 caller = Reflection.getCallerClass();
466 }
467 return forName(name, initialize, loader, caller);
468 }
469
470 // Caller-sensitive adapter method for reflective invocation
471 @CallerSensitiveAdapter
472 private static Class<?> forName(String name, boolean initialize, ClassLoader loader, Class<?> caller)
473 throws ClassNotFoundException
474 {
475 @SuppressWarnings("removal")
476 SecurityManager sm = System.getSecurityManager();
477 if (sm != null) {
478 // Reflective call to get caller class is only needed if a security manager
479 // is present. Avoid the overhead of making this call otherwise.
480 if (loader == null) {
481 ClassLoader ccl = ClassLoader.getClassLoader(caller);
482 if (ccl != null) {
483 sm.checkPermission(
484 SecurityConstants.GET_CLASSLOADER_PERMISSION);
485 }
486 }
487 }
488 return forName0(name, initialize, loader, caller);
489 }
490
491 /** Called after security check for system loader access checks have been made. */
492 private static native Class<?> forName0(String name, boolean initialize,
493 ClassLoader loader,
494 Class<?> caller)
495 throws ClassNotFoundException;
496
497
498 /**
499 * Returns the {@code Class} with the given <a href="ClassLoader.html#binary-name">
500 * binary name</a> in the given module.
501 *
502 * <p> This method attempts to locate and load the class or interface.
503 * It does not link the class, and does not run the class initializer.
504 * If the class is not found, this method returns {@code null}. </p>
505 *
506 * <p> If the class loader of the given module defines other modules and
507 * the given name is a class defined in a different module, this method
508 * returns {@code null} after the class is loaded. </p>
509 *
510 * <p> This method does not check whether the requested class is
511 * accessible to its caller. </p>
512 *
513 * @apiNote
514 * This method returns {@code null} on failure rather than
515 * throwing a {@link ClassNotFoundException}, as is done by
516 * the {@link #forName(String, boolean, ClassLoader)} method.
517 * The security check is a stack-based permission check if the caller
518 * loads a class in another module.
519 *
520 * @param module A module
521 * @param name The <a href="ClassLoader.html#binary-name">binary name</a>
522 * of the class
523 * @return {@code Class} object of the given name defined in the given module;
524 * {@code null} if not found.
525 *
526 * @throws NullPointerException if the given module or name is {@code null}
527 *
528 * @throws LinkageError if the linkage fails
529 *
530 * @throws SecurityException
531 * <ul>
532 * <li> if the caller is not the specified module and
533 * {@code RuntimePermission("getClassLoader")} permission is denied; or</li>
534 * <li> access to the module content is denied. For example,
535 * permission check will be performed when a class loader calls
536 * {@link ModuleReader#open(String)} to read the bytes of a class file
537 * in a module.</li>
538 * </ul>
539 *
540 * @jls 12.2 Loading of Classes and Interfaces
541 * @jls 12.3 Linking of Classes and Interfaces
542 * @since 9
543 */
544 @SuppressWarnings("removal")
545 @CallerSensitive
546 public static Class<?> forName(Module module, String name) {
547 Class<?> caller = null;
548 SecurityManager sm = System.getSecurityManager();
549 if (sm != null) {
550 caller = Reflection.getCallerClass();
551 }
552 return forName(module, name, caller);
553 }
554
555 // Caller-sensitive adapter method for reflective invocation
556 @SuppressWarnings("removal")
557 @CallerSensitiveAdapter
558 private static Class<?> forName(Module module, String name, Class<?> caller) {
559 Objects.requireNonNull(module);
560 Objects.requireNonNull(name);
561
562 ClassLoader cl;
563 SecurityManager sm = System.getSecurityManager();
564 if (sm != null) {
565 if (caller != null && caller.getModule() != module) {
566 // if caller is null, Class.forName is the last java frame on the stack.
567 // java.base has all permissions
568 sm.checkPermission(SecurityConstants.GET_CLASSLOADER_PERMISSION);
569 }
570 PrivilegedAction<ClassLoader> pa = module::getClassLoader;
571 cl = AccessController.doPrivileged(pa);
572 } else {
573 cl = module.getClassLoader();
574 }
575
576 if (cl != null) {
577 return cl.loadClass(module, name);
578 } else {
579 return BootLoader.loadClass(module, name);
580 }
581 }
582
583 /**
584 * Creates a new instance of the class represented by this {@code Class}
585 * object. The class is instantiated as if by a {@code new}
586 * expression with an empty argument list. The class is initialized if it
587 * has not already been initialized.
588 *
589 * @deprecated This method propagates any exception thrown by the
590 * nullary constructor, including a checked exception. Use of
591 * this method effectively bypasses the compile-time exception
592 * checking that would otherwise be performed by the compiler.
593 * The {@link
594 * java.lang.reflect.Constructor#newInstance(java.lang.Object...)
595 * Constructor.newInstance} method avoids this problem by wrapping
596 * any exception thrown by the constructor in a (checked) {@link
597 * java.lang.reflect.InvocationTargetException}.
598 *
599 * <p>The call
600 *
601 * <pre>{@code
602 * clazz.newInstance()
603 * }</pre>
604 *
605 * can be replaced by
606 *
607 * <pre>{@code
608 * clazz.getDeclaredConstructor().newInstance()
609 * }</pre>
610 *
611 * The latter sequence of calls is inferred to be able to throw
612 * the additional exception types {@link
613 * InvocationTargetException} and {@link
614 * NoSuchMethodException}. Both of these exception types are
615 * subclasses of {@link ReflectiveOperationException}.
616 *
617 * @return a newly allocated instance of the class represented by this
618 * object.
619 * @throws IllegalAccessException if the class or its nullary
620 * constructor is not accessible.
621 * @throws InstantiationException
622 * if this {@code Class} represents an abstract class,
623 * an interface, an array class, a primitive type, or void;
624 * or if the class has no nullary constructor;
625 * or if the instantiation fails for some other reason.
626 * @throws ExceptionInInitializerError if the initialization
627 * provoked by this method fails.
628 * @throws SecurityException
629 * If a security manager, <i>s</i>, is present and
630 * the caller's class loader is not the same as or an
631 * ancestor of the class loader for the current class and
632 * invocation of {@link SecurityManager#checkPackageAccess
633 * s.checkPackageAccess()} denies access to the package
634 * of this class.
635 */
636 @SuppressWarnings("removal")
637 @CallerSensitive
638 @Deprecated(since="9")
639 public T newInstance()
640 throws InstantiationException, IllegalAccessException
641 {
642 SecurityManager sm = System.getSecurityManager();
643 if (sm != null) {
644 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), false);
645 }
646
647 // Constructor lookup
648 Constructor<T> tmpConstructor = cachedConstructor;
649 if (tmpConstructor == null) {
650 if (this == Class.class) {
651 throw new IllegalAccessException(
652 "Can not call newInstance() on the Class for java.lang.Class"
653 );
654 }
655 try {
656 Class<?>[] empty = {};
657 final Constructor<T> c = getReflectionFactory().copyConstructor(
658 getConstructor0(empty, Member.DECLARED));
659 // Disable accessibility checks on the constructor
660 // access check is done with the true caller
661 java.security.AccessController.doPrivileged(
662 new java.security.PrivilegedAction<>() {
663 public Void run() {
664 c.setAccessible(true);
665 return null;
666 }
667 });
668 cachedConstructor = tmpConstructor = c;
669 } catch (NoSuchMethodException e) {
670 throw (InstantiationException)
671 new InstantiationException(getName()).initCause(e);
672 }
673 }
674
675 try {
676 Class<?> caller = Reflection.getCallerClass();
677 return getReflectionFactory().newInstance(tmpConstructor, null, caller);
678 } catch (InvocationTargetException e) {
679 Unsafe.getUnsafe().throwException(e.getTargetException());
680 // Not reached
681 return null;
682 }
683 }
684
685 private transient volatile Constructor<T> cachedConstructor;
686
687 /**
688 * Determines if the specified {@code Object} is assignment-compatible
689 * with the object represented by this {@code Class}. This method is
690 * the dynamic equivalent of the Java language {@code instanceof}
691 * operator. The method returns {@code true} if the specified
692 * {@code Object} argument is non-null and can be cast to the
693 * reference type represented by this {@code Class} object without
694 * raising a {@code ClassCastException.} It returns {@code false}
695 * otherwise.
696 *
697 * <p> Specifically, if this {@code Class} object represents a
698 * declared class, this method returns {@code true} if the specified
699 * {@code Object} argument is an instance of the represented class (or
700 * of any of its subclasses); it returns {@code false} otherwise. If
701 * this {@code Class} object represents an array class, this method
702 * returns {@code true} if the specified {@code Object} argument
703 * can be converted to an object of the array class by an identity
704 * conversion or by a widening reference conversion; it returns
705 * {@code false} otherwise. If this {@code Class} object
706 * represents an interface, this method returns {@code true} if the
707 * class or any superclass of the specified {@code Object} argument
708 * implements this interface; it returns {@code false} otherwise. If
709 * this {@code Class} object represents a primitive type, this method
710 * returns {@code false}.
711 *
712 * @param obj the object to check
713 * @return true if {@code obj} is an instance of this class
714 *
715 * @since 1.1
716 */
717 @IntrinsicCandidate
718 public native boolean isInstance(Object obj);
719
720
721 /**
722 * Determines if the class or interface represented by this
723 * {@code Class} object is either the same as, or is a superclass or
724 * superinterface of, the class or interface represented by the specified
725 * {@code Class} parameter. It returns {@code true} if so;
726 * otherwise it returns {@code false}. If this {@code Class}
727 * object represents a primitive type, this method returns
728 * {@code true} if the specified {@code Class} parameter is
729 * exactly this {@code Class} object; otherwise it returns
730 * {@code false}.
731 *
732 * <p> Specifically, this method tests whether the type represented by the
733 * specified {@code Class} parameter can be converted to the type
734 * represented by this {@code Class} object via an identity conversion
735 * or via a widening reference conversion. See <cite>The Java Language
736 * Specification</cite>, sections {@jls 5.1.1} and {@jls 5.1.4},
737 * for details.
738 *
739 * @param cls the {@code Class} object to be checked
740 * @return the {@code boolean} value indicating whether objects of the
741 * type {@code cls} can be assigned to objects of this class
742 * @throws NullPointerException if the specified Class parameter is
743 * null.
744 * @since 1.1
745 */
746 @IntrinsicCandidate
747 public native boolean isAssignableFrom(Class<?> cls);
748
749
750 /**
751 * Determines if this {@code Class} object represents an
752 * interface type.
753 *
754 * @return {@code true} if this {@code Class} object represents an interface;
755 * {@code false} otherwise.
756 */
757 @IntrinsicCandidate
758 public native boolean isInterface();
759
760
761 /**
762 * Determines if this {@code Class} object represents an array class.
763 *
764 * @return {@code true} if this {@code Class} object represents an array class;
765 * {@code false} otherwise.
766 * @since 1.1
767 */
768 @IntrinsicCandidate
769 public native boolean isArray();
770
771
772 /**
773 * Determines if the specified {@code Class} object represents a
774 * primitive type.
775 *
776 * <p> There are nine predefined {@code Class} objects to represent
777 * the eight primitive types and void. These are created by the Java
778 * Virtual Machine, and have the same names as the primitive types that
779 * they represent, namely {@code boolean}, {@code byte},
780 * {@code char}, {@code short}, {@code int},
781 * {@code long}, {@code float}, and {@code double}.
782 *
783 * <p> These objects may only be accessed via the following public static
784 * final variables, and are the only {@code Class} objects for which
785 * this method returns {@code true}.
786 *
787 * @return true if and only if this class represents a primitive type
788 *
789 * @see java.lang.Boolean#TYPE
790 * @see java.lang.Character#TYPE
791 * @see java.lang.Byte#TYPE
792 * @see java.lang.Short#TYPE
793 * @see java.lang.Integer#TYPE
794 * @see java.lang.Long#TYPE
795 * @see java.lang.Float#TYPE
796 * @see java.lang.Double#TYPE
797 * @see java.lang.Void#TYPE
798 * @since 1.1
799 */
800 @IntrinsicCandidate
801 public native boolean isPrimitive();
802
803 /**
804 * Returns true if this {@code Class} object represents an annotation
805 * interface. Note that if this method returns true, {@link #isInterface()}
806 * would also return true, as all annotation interfaces are also interfaces.
807 *
808 * @return {@code true} if this {@code Class} object represents an annotation
809 * interface; {@code false} otherwise
810 * @since 1.5
811 */
812 public boolean isAnnotation() {
813 return (getModifiers() & ANNOTATION) != 0;
814 }
815
816 /**
817 *{@return {@code true} if and only if this class has the synthetic modifier
818 * bit set}
819 *
820 * @jls 13.1 The Form of a Binary
821 * @jvms 4.1 The {@code ClassFile} Structure
822 * @see <a
823 * href="{@docRoot}/java.base/java/lang/reflect/package-summary.html#LanguageJvmModel">Java
824 * programming language and JVM modeling in core reflection</a>
825 * @since 1.5
826 */
827 public boolean isSynthetic() {
828 return (getModifiers() & SYNTHETIC) != 0;
829 }
830
831 /**
832 * Returns the name of the entity (class, interface, array class,
833 * primitive type, or void) represented by this {@code Class} object.
834 *
835 * <p> If this {@code Class} object represents a class or interface,
836 * not an array class, then:
837 * <ul>
838 * <li> If the class or interface is not {@linkplain #isHidden() hidden},
839 * then the <a href="ClassLoader.html#binary-name">binary name</a>
840 * of the class or interface is returned.
841 * <li> If the class or interface is hidden, then the result is a string
842 * of the form: {@code N + '/' + <suffix>}
843 * where {@code N} is the <a href="ClassLoader.html#binary-name">binary name</a>
844 * indicated by the {@code class} file passed to
845 * {@link java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
846 * Lookup::defineHiddenClass}, and {@code <suffix>} is an unqualified name.
847 * </ul>
848 *
849 * <p> If this {@code Class} object represents an array class, then
850 * the result is a string consisting of one or more '{@code [}' characters
851 * representing the depth of the array nesting, followed by the element
852 * type as encoded using the following table:
853 *
854 * <blockquote><table class="striped">
855 * <caption style="display:none">Element types and encodings</caption>
856 * <thead>
857 * <tr><th scope="col"> Element Type <th scope="col"> Encoding
858 * </thead>
859 * <tbody style="text-align:left">
860 * <tr><th scope="row"> {@code boolean} <td style="text-align:center"> {@code Z}
861 * <tr><th scope="row"> {@code byte} <td style="text-align:center"> {@code B}
862 * <tr><th scope="row"> {@code char} <td style="text-align:center"> {@code C}
863 * <tr><th scope="row"> class or interface with <a href="ClassLoader.html#binary-name">binary name</a> <i>N</i>
864 * <td style="text-align:center"> {@code L}<em>N</em>{@code ;}
865 * <tr><th scope="row"> {@code double} <td style="text-align:center"> {@code D}
866 * <tr><th scope="row"> {@code float} <td style="text-align:center"> {@code F}
867 * <tr><th scope="row"> {@code int} <td style="text-align:center"> {@code I}
868 * <tr><th scope="row"> {@code long} <td style="text-align:center"> {@code J}
869 * <tr><th scope="row"> {@code short} <td style="text-align:center"> {@code S}
870 * </tbody>
871 * </table></blockquote>
872 *
873 * <p> If this {@code Class} object represents a primitive type or {@code void},
874 * then the result is a string with the same spelling as the Java language
875 * keyword which corresponds to the primitive type or {@code void}.
876 *
877 * <p> Examples:
878 * <blockquote><pre>
879 * String.class.getName()
880 * returns "java.lang.String"
881 * byte.class.getName()
882 * returns "byte"
883 * (new Object[3]).getClass().getName()
884 * returns "[Ljava.lang.Object;"
885 * (new int[3][4][5][6][7][8][9]).getClass().getName()
886 * returns "[[[[[[[I"
887 * </pre></blockquote>
888 *
889 * @return the name of the class, interface, or other entity
890 * represented by this {@code Class} object.
891 * @jls 13.1 The Form of a Binary
892 */
893 public String getName() {
894 String name = this.name;
895 return name != null ? name : initClassName();
896 }
897
898 // Cache the name to reduce the number of calls into the VM.
899 // This field would be set by VM itself during initClassName call.
900 private transient String name;
901 private native String initClassName();
902
903 /**
904 * Returns the class loader for the class. Some implementations may use
905 * null to represent the bootstrap class loader. This method will return
906 * null in such implementations if this class was loaded by the bootstrap
907 * class loader.
908 *
909 * <p>If this {@code Class} object
910 * represents a primitive type or void, null is returned.
911 *
912 * @return the class loader that loaded the class or interface
913 * represented by this {@code Class} object.
914 * @throws SecurityException
915 * if a security manager is present, and the caller's class loader
916 * is not {@code null} and is not the same as or an ancestor of the
917 * class loader for the class whose class loader is requested,
918 * and the caller does not have the
919 * {@link RuntimePermission}{@code ("getClassLoader")}
920 * @see java.lang.ClassLoader
921 * @see SecurityManager#checkPermission
922 * @see java.lang.RuntimePermission
923 */
924 @CallerSensitive
925 @ForceInline // to ensure Reflection.getCallerClass optimization
926 public ClassLoader getClassLoader() {
927 ClassLoader cl = classLoader;
928 if (cl == null)
929 return null;
930 @SuppressWarnings("removal")
931 SecurityManager sm = System.getSecurityManager();
932 if (sm != null) {
933 ClassLoader.checkClassLoaderPermission(cl, Reflection.getCallerClass());
934 }
935 return cl;
936 }
937
938 // Package-private to allow ClassLoader access
939 ClassLoader getClassLoader0() { return classLoader; }
940
941 /**
942 * Returns the module that this class or interface is a member of.
943 *
944 * If this class represents an array type then this method returns the
945 * {@code Module} for the element type. If this class represents a
946 * primitive type or void, then the {@code Module} object for the
947 * {@code java.base} module is returned.
948 *
949 * If this class is in an unnamed module then the {@linkplain
950 * ClassLoader#getUnnamedModule() unnamed} {@code Module} of the class
951 * loader for this class is returned.
952 *
953 * @return the module that this class or interface is a member of
954 *
955 * @since 9
956 */
957 public Module getModule() {
958 return module;
959 }
960
961 // set by VM
962 private transient Module module;
963
964 // Initialized in JVM not by private constructor
965 // This field is filtered from reflection access, i.e. getDeclaredField
966 // will throw NoSuchFieldException
967 private final ClassLoader classLoader;
968
969 // Set by VM
970 private transient Object classData;
971
972 // package-private
973 Object getClassData() {
974 return classData;
975 }
976
977 /**
978 * Returns an array of {@code TypeVariable} objects that represent the
979 * type variables declared by the generic declaration represented by this
980 * {@code GenericDeclaration} object, in declaration order. Returns an
981 * array of length 0 if the underlying generic declaration declares no type
982 * variables.
983 *
984 * @return an array of {@code TypeVariable} objects that represent
985 * the type variables declared by this generic declaration
986 * @throws java.lang.reflect.GenericSignatureFormatError if the generic
987 * signature of this generic declaration does not conform to
988 * the format specified in section {@jvms 4.7.9} of
989 * <cite>The Java Virtual Machine Specification</cite>
990 * @since 1.5
991 */
992 @SuppressWarnings("unchecked")
993 public TypeVariable<Class<T>>[] getTypeParameters() {
994 ClassRepository info = getGenericInfo();
995 if (info != null)
996 return (TypeVariable<Class<T>>[])info.getTypeParameters();
997 else
998 return (TypeVariable<Class<T>>[])new TypeVariable<?>[0];
999 }
1000
1001
1002 /**
1003 * Returns the {@code Class} representing the direct superclass of the
1004 * entity (class, interface, primitive type or void) represented by
1005 * this {@code Class}. If this {@code Class} represents either the
1006 * {@code Object} class, an interface, a primitive type, or void, then
1007 * null is returned. If this {@code Class} object represents an array class
1008 * then the {@code Class} object representing the {@code Object} class is
1009 * returned.
1010 *
1011 * @return the direct superclass of the class represented by this {@code Class} object
1012 */
1013 @IntrinsicCandidate
1014 public native Class<? super T> getSuperclass();
1015
1016
1017 /**
1018 * Returns the {@code Type} representing the direct superclass of
1019 * the entity (class, interface, primitive type or void) represented by
1020 * this {@code Class} object.
1021 *
1022 * <p>If the superclass is a parameterized type, the {@code Type}
1023 * object returned must accurately reflect the actual type
1024 * arguments used in the source code. The parameterized type
1025 * representing the superclass is created if it had not been
1026 * created before. See the declaration of {@link
1027 * java.lang.reflect.ParameterizedType ParameterizedType} for the
1028 * semantics of the creation process for parameterized types. If
1029 * this {@code Class} object represents either the {@code Object}
1030 * class, an interface, a primitive type, or void, then null is
1031 * returned. If this {@code Class} object represents an array class
1032 * then the {@code Class} object representing the {@code Object} class is
1033 * returned.
1034 *
1035 * @throws java.lang.reflect.GenericSignatureFormatError if the generic
1036 * class signature does not conform to the format specified in
1037 * section {@jvms 4.7.9} of <cite>The Java Virtual
1038 * Machine Specification</cite>
1039 * @throws TypeNotPresentException if the generic superclass
1040 * refers to a non-existent type declaration
1041 * @throws java.lang.reflect.MalformedParameterizedTypeException if the
1042 * generic superclass refers to a parameterized type that cannot be
1043 * instantiated for any reason
1044 * @return the direct superclass of the class represented by this {@code Class} object
1045 * @since 1.5
1046 */
1047 public Type getGenericSuperclass() {
1048 ClassRepository info = getGenericInfo();
1049 if (info == null) {
1050 return getSuperclass();
1051 }
1052
1053 // Historical irregularity:
1054 // Generic signature marks interfaces with superclass = Object
1055 // but this API returns null for interfaces
1056 if (isInterface()) {
1057 return null;
1058 }
1059
1060 return info.getSuperclass();
1061 }
1062
1063 /**
1064 * Gets the package of this class.
1065 *
1066 * <p>If this class represents an array type, a primitive type or void,
1067 * this method returns {@code null}.
1068 *
1069 * @return the package of this class.
1070 * @revised 9
1071 */
1072 public Package getPackage() {
1073 if (isPrimitive() || isArray()) {
1074 return null;
1075 }
1076 ClassLoader cl = classLoader;
1077 return cl != null ? cl.definePackage(this)
1078 : BootLoader.definePackage(this);
1079 }
1080
1081 /**
1082 * Returns the fully qualified package name.
1083 *
1084 * <p> If this class is a top level class, then this method returns the fully
1085 * qualified name of the package that the class is a member of, or the
1086 * empty string if the class is in an unnamed package.
1087 *
1088 * <p> If this class is a member class, then this method is equivalent to
1089 * invoking {@code getPackageName()} on the {@linkplain #getEnclosingClass
1090 * enclosing class}.
1091 *
1092 * <p> If this class is a {@linkplain #isLocalClass local class} or an {@linkplain
1093 * #isAnonymousClass() anonymous class}, then this method is equivalent to
1094 * invoking {@code getPackageName()} on the {@linkplain #getDeclaringClass
1095 * declaring class} of the {@linkplain #getEnclosingMethod enclosing method} or
1096 * {@linkplain #getEnclosingConstructor enclosing constructor}.
1097 *
1098 * <p> If this class represents an array type then this method returns the
1099 * package name of the element type. If this class represents a primitive
1100 * type or void then the package name "{@code java.lang}" is returned.
1101 *
1102 * @return the fully qualified package name
1103 *
1104 * @since 9
1105 * @jls 6.7 Fully Qualified Names
1106 */
1107 public String getPackageName() {
1108 String pn = this.packageName;
1109 if (pn == null) {
1110 Class<?> c = isArray() ? elementType() : this;
1111 if (c.isPrimitive()) {
1112 pn = "java.lang";
1113 } else {
1114 String cn = c.getName();
1115 int dot = cn.lastIndexOf('.');
1116 pn = (dot != -1) ? cn.substring(0, dot).intern() : "";
1117 }
1118 this.packageName = pn;
1119 }
1120 return pn;
1121 }
1122
1123 // cached package name
1124 private transient String packageName;
1125
1126 /**
1127 * Returns the interfaces directly implemented by the class or interface
1128 * represented by this {@code Class} object.
1129 *
1130 * <p>If this {@code Class} object represents a class, the return value is an array
1131 * containing objects representing all interfaces directly implemented by
1132 * the class. The order of the interface objects in the array corresponds
1133 * to the order of the interface names in the {@code implements} clause of
1134 * the declaration of the class represented by this {@code Class} object. For example,
1135 * given the declaration:
1136 * <blockquote>
1137 * {@code class Shimmer implements FloorWax, DessertTopping { ... }}
1138 * </blockquote>
1139 * suppose the value of {@code s} is an instance of
1140 * {@code Shimmer}; the value of the expression:
1141 * <blockquote>
1142 * {@code s.getClass().getInterfaces()[0]}
1143 * </blockquote>
1144 * is the {@code Class} object that represents interface
1145 * {@code FloorWax}; and the value of:
1146 * <blockquote>
1147 * {@code s.getClass().getInterfaces()[1]}
1148 * </blockquote>
1149 * is the {@code Class} object that represents interface
1150 * {@code DessertTopping}.
1151 *
1152 * <p>If this {@code Class} object represents an interface, the array contains objects
1153 * representing all interfaces directly extended by the interface. The
1154 * order of the interface objects in the array corresponds to the order of
1155 * the interface names in the {@code extends} clause of the declaration of
1156 * the interface represented by this {@code Class} object.
1157 *
1158 * <p>If this {@code Class} object represents a class or interface that implements no
1159 * interfaces, the method returns an array of length 0.
1160 *
1161 * <p>If this {@code Class} object represents a primitive type or void, the method
1162 * returns an array of length 0.
1163 *
1164 * <p>If this {@code Class} object represents an array type, the
1165 * interfaces {@code Cloneable} and {@code java.io.Serializable} are
1166 * returned in that order.
1167 *
1168 * @return an array of interfaces directly implemented by this class
1169 */
1170 public Class<?>[] getInterfaces() {
1171 // defensively copy before handing over to user code
1172 return getInterfaces(true);
1173 }
1174
1175 private Class<?>[] getInterfaces(boolean cloneArray) {
1176 ReflectionData<T> rd = reflectionData();
1177 if (rd == null) {
1178 // no cloning required
1179 return getInterfaces0();
1180 } else {
1181 Class<?>[] interfaces = rd.interfaces;
1182 if (interfaces == null) {
1183 interfaces = getInterfaces0();
1184 rd.interfaces = interfaces;
1185 }
1186 // defensively copy if requested
1187 return cloneArray ? interfaces.clone() : interfaces;
1188 }
1189 }
1190
1191 private native Class<?>[] getInterfaces0();
1192
1193 /**
1194 * Returns the {@code Type}s representing the interfaces
1195 * directly implemented by the class or interface represented by
1196 * this {@code Class} object.
1197 *
1198 * <p>If a superinterface is a parameterized type, the
1199 * {@code Type} object returned for it must accurately reflect
1200 * the actual type arguments used in the source code. The
1201 * parameterized type representing each superinterface is created
1202 * if it had not been created before. See the declaration of
1203 * {@link java.lang.reflect.ParameterizedType ParameterizedType}
1204 * for the semantics of the creation process for parameterized
1205 * types.
1206 *
1207 * <p>If this {@code Class} object represents a class, the return value is an array
1208 * containing objects representing all interfaces directly implemented by
1209 * the class. The order of the interface objects in the array corresponds
1210 * to the order of the interface names in the {@code implements} clause of
1211 * the declaration of the class represented by this {@code Class} object.
1212 *
1213 * <p>If this {@code Class} object represents an interface, the array contains objects
1214 * representing all interfaces directly extended by the interface. The
1215 * order of the interface objects in the array corresponds to the order of
1216 * the interface names in the {@code extends} clause of the declaration of
1217 * the interface represented by this {@code Class} object.
1218 *
1219 * <p>If this {@code Class} object represents a class or interface that implements no
1220 * interfaces, the method returns an array of length 0.
1221 *
1222 * <p>If this {@code Class} object represents a primitive type or void, the method
1223 * returns an array of length 0.
1224 *
1225 * <p>If this {@code Class} object represents an array type, the
1226 * interfaces {@code Cloneable} and {@code java.io.Serializable} are
1227 * returned in that order.
1228 *
1229 * @throws java.lang.reflect.GenericSignatureFormatError
1230 * if the generic class signature does not conform to the
1231 * format specified in section {@jvms 4.7.9} of <cite>The
1232 * Java Virtual Machine Specification</cite>
1233 * @throws TypeNotPresentException if any of the generic
1234 * superinterfaces refers to a non-existent type declaration
1235 * @throws java.lang.reflect.MalformedParameterizedTypeException
1236 * if any of the generic superinterfaces refer to a parameterized
1237 * type that cannot be instantiated for any reason
1238 * @return an array of interfaces directly implemented by this class
1239 * @since 1.5
1240 */
1241 public Type[] getGenericInterfaces() {
1242 ClassRepository info = getGenericInfo();
1243 return (info == null) ? getInterfaces() : info.getSuperInterfaces();
1244 }
1245
1246
1247 /**
1248 * Returns the {@code Class} representing the component type of an
1249 * array. If this class does not represent an array class this method
1250 * returns null.
1251 *
1252 * @return the {@code Class} representing the component type of this
1253 * class if this class is an array
1254 * @see java.lang.reflect.Array
1255 * @since 1.1
1256 */
1257 public Class<?> getComponentType() {
1258 // Only return for array types. Storage may be reused for Class for instance types.
1259 if (isArray()) {
1260 return componentType;
1261 } else {
1262 return null;
1263 }
1264 }
1265
1266 private final Class<?> componentType;
1267
1268 /*
1269 * Returns the {@code Class} representing the element type of an array class.
1270 * If this class does not represent an array class, then this method returns
1271 * {@code null}.
1272 */
1273 private Class<?> elementType() {
1274 if (!isArray()) return null;
1275
1276 Class<?> c = this;
1277 while (c.isArray()) {
1278 c = c.getComponentType();
1279 }
1280 return c;
1281 }
1282
1283 /**
1284 * Returns the Java language modifiers for this class or interface, encoded
1285 * in an integer. The modifiers consist of the Java Virtual Machine's
1286 * constants for {@code public}, {@code protected},
1287 * {@code private}, {@code final}, {@code static},
1288 * {@code abstract} and {@code interface}; they should be decoded
1289 * using the methods of class {@code Modifier}.
1290 *
1291 * <p> If the underlying class is an array class, then its
1292 * {@code public}, {@code private} and {@code protected}
1293 * modifiers are the same as those of its component type. If this
1294 * {@code Class} object represents a primitive type or void, its
1295 * {@code public} modifier is always {@code true}, and its
1296 * {@code protected} and {@code private} modifiers are always
1297 * {@code false}. If this {@code Class} object represents an array class, a
1298 * primitive type or void, then its {@code final} modifier is always
1299 * {@code true} and its interface modifier is always
1300 * {@code false}. The values of its other modifiers are not determined
1301 * by this specification.
1302 *
1303 * <p> The modifier encodings are defined in section {@jvms 4.1}
1304 * of <cite>The Java Virtual Machine Specification</cite>.
1305 *
1306 * @return the {@code int} representing the modifiers for this class
1307 * @see java.lang.reflect.Modifier
1308 * @see <a
1309 * href="{@docRoot}/java.base/java/lang/reflect/package-summary.html#LanguageJvmModel">Java
1310 * programming language and JVM modeling in core reflection</a>
1311 * @since 1.1
1312 * @jls 8.1.1 Class Modifiers
1313 * @jls 9.1.1. Interface Modifiers
1314 */
1315 @IntrinsicCandidate
1316 public native int getModifiers();
1317
1318
1319 /**
1320 * Gets the signers of this class.
1321 *
1322 * @return the signers of this class, or null if there are no signers. In
1323 * particular, this method returns null if this {@code Class} object represents
1324 * a primitive type or void.
1325 * @since 1.1
1326 */
1327 public native Object[] getSigners();
1328
1329
1330 /**
1331 * Set the signers of this class.
1332 */
1333 native void setSigners(Object[] signers);
1334
1335
1336 /**
1337 * If this {@code Class} object represents a local or anonymous
1338 * class within a method, returns a {@link
1339 * java.lang.reflect.Method Method} object representing the
1340 * immediately enclosing method of the underlying class. Returns
1341 * {@code null} otherwise.
1342 *
1343 * In particular, this method returns {@code null} if the underlying
1344 * class is a local or anonymous class immediately enclosed by a class or
1345 * interface declaration, instance initializer or static initializer.
1346 *
1347 * @return the immediately enclosing method of the underlying class, if
1348 * that class is a local or anonymous class; otherwise {@code null}.
1349 *
1350 * @throws SecurityException
1351 * If a security manager, <i>s</i>, is present and any of the
1352 * following conditions is met:
1353 *
1354 * <ul>
1355 *
1356 * <li> the caller's class loader is not the same as the
1357 * class loader of the enclosing class and invocation of
1358 * {@link SecurityManager#checkPermission
1359 * s.checkPermission} method with
1360 * {@code RuntimePermission("accessDeclaredMembers")}
1361 * denies access to the methods within the enclosing class
1362 *
1363 * <li> the caller's class loader is not the same as or an
1364 * ancestor of the class loader for the enclosing class and
1365 * invocation of {@link SecurityManager#checkPackageAccess
1366 * s.checkPackageAccess()} denies access to the package
1367 * of the enclosing class
1368 *
1369 * </ul>
1370 * @since 1.5
1371 */
1372 @CallerSensitive
1373 public Method getEnclosingMethod() throws SecurityException {
1374 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1375
1376 if (enclosingInfo == null)
1377 return null;
1378 else {
1379 if (!enclosingInfo.isMethod())
1380 return null;
1381
1382 MethodRepository typeInfo = MethodRepository.make(enclosingInfo.getDescriptor(),
1383 getFactory());
1384 Class<?> returnType = toClass(typeInfo.getReturnType());
1385 Type [] parameterTypes = typeInfo.getParameterTypes();
1386 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length];
1387
1388 // Convert Types to Classes; returned types *should*
1389 // be class objects since the methodDescriptor's used
1390 // don't have generics information
1391 for(int i = 0; i < parameterClasses.length; i++)
1392 parameterClasses[i] = toClass(parameterTypes[i]);
1393
1394 // Perform access check
1395 final Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass();
1396 @SuppressWarnings("removal")
1397 SecurityManager sm = System.getSecurityManager();
1398 if (sm != null) {
1399 enclosingCandidate.checkMemberAccess(sm, Member.DECLARED,
1400 Reflection.getCallerClass(), true);
1401 }
1402 Method[] candidates = enclosingCandidate.privateGetDeclaredMethods(false);
1403
1404 /*
1405 * Loop over all declared methods; match method name,
1406 * number of and type of parameters, *and* return
1407 * type. Matching return type is also necessary
1408 * because of covariant returns, etc.
1409 */
1410 ReflectionFactory fact = getReflectionFactory();
1411 for (Method m : candidates) {
1412 if (m.getName().equals(enclosingInfo.getName()) &&
1413 arrayContentsEq(parameterClasses,
1414 fact.getExecutableSharedParameterTypes(m))) {
1415 // finally, check return type
1416 if (m.getReturnType().equals(returnType)) {
1417 return fact.copyMethod(m);
1418 }
1419 }
1420 }
1421
1422 throw new InternalError("Enclosing method not found");
1423 }
1424 }
1425
1426 private native Object[] getEnclosingMethod0();
1427
1428 private EnclosingMethodInfo getEnclosingMethodInfo() {
1429 Object[] enclosingInfo = getEnclosingMethod0();
1430 if (enclosingInfo == null)
1431 return null;
1432 else {
1433 return new EnclosingMethodInfo(enclosingInfo);
1434 }
1435 }
1436
1437 private static final class EnclosingMethodInfo {
1438 private final Class<?> enclosingClass;
1439 private final String name;
1440 private final String descriptor;
1441
1442 static void validate(Object[] enclosingInfo) {
1443 if (enclosingInfo.length != 3)
1444 throw new InternalError("Malformed enclosing method information");
1445 try {
1446 // The array is expected to have three elements:
1447
1448 // the immediately enclosing class
1449 Class<?> enclosingClass = (Class<?>)enclosingInfo[0];
1450 assert(enclosingClass != null);
1451
1452 // the immediately enclosing method or constructor's
1453 // name (can be null).
1454 String name = (String)enclosingInfo[1];
1455
1456 // the immediately enclosing method or constructor's
1457 // descriptor (null iff name is).
1458 String descriptor = (String)enclosingInfo[2];
1459 assert((name != null && descriptor != null) || name == descriptor);
1460 } catch (ClassCastException cce) {
1461 throw new InternalError("Invalid type in enclosing method information", cce);
1462 }
1463 }
1464
1465 EnclosingMethodInfo(Object[] enclosingInfo) {
1466 validate(enclosingInfo);
1467 this.enclosingClass = (Class<?>)enclosingInfo[0];
1468 this.name = (String)enclosingInfo[1];
1469 this.descriptor = (String)enclosingInfo[2];
1470 }
1471
1472 boolean isPartial() {
1473 return enclosingClass == null || name == null || descriptor == null;
1474 }
1475
1476 boolean isConstructor() { return !isPartial() && "<init>".equals(name); }
1477
1478 boolean isMethod() { return !isPartial() && !isConstructor() && !"<clinit>".equals(name); }
1479
1480 Class<?> getEnclosingClass() { return enclosingClass; }
1481
1482 String getName() { return name; }
1483
1484 String getDescriptor() { return descriptor; }
1485
1486 }
1487
1488 private static Class<?> toClass(Type o) {
1489 if (o instanceof GenericArrayType)
1490 return Array.newInstance(toClass(((GenericArrayType)o).getGenericComponentType()),
1491 0)
1492 .getClass();
1493 return (Class<?>)o;
1494 }
1495
1496 /**
1497 * If this {@code Class} object represents a local or anonymous
1498 * class within a constructor, returns a {@link
1499 * java.lang.reflect.Constructor Constructor} object representing
1500 * the immediately enclosing constructor of the underlying
1501 * class. Returns {@code null} otherwise. In particular, this
1502 * method returns {@code null} if the underlying class is a local
1503 * or anonymous class immediately enclosed by a class or
1504 * interface declaration, instance initializer or static initializer.
1505 *
1506 * @return the immediately enclosing constructor of the underlying class, if
1507 * that class is a local or anonymous class; otherwise {@code null}.
1508 * @throws SecurityException
1509 * If a security manager, <i>s</i>, is present and any of the
1510 * following conditions is met:
1511 *
1512 * <ul>
1513 *
1514 * <li> the caller's class loader is not the same as the
1515 * class loader of the enclosing class and invocation of
1516 * {@link SecurityManager#checkPermission
1517 * s.checkPermission} method with
1518 * {@code RuntimePermission("accessDeclaredMembers")}
1519 * denies access to the constructors within the enclosing class
1520 *
1521 * <li> the caller's class loader is not the same as or an
1522 * ancestor of the class loader for the enclosing class and
1523 * invocation of {@link SecurityManager#checkPackageAccess
1524 * s.checkPackageAccess()} denies access to the package
1525 * of the enclosing class
1526 *
1527 * </ul>
1528 * @since 1.5
1529 */
1530 @CallerSensitive
1531 public Constructor<?> getEnclosingConstructor() throws SecurityException {
1532 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1533
1534 if (enclosingInfo == null)
1535 return null;
1536 else {
1537 if (!enclosingInfo.isConstructor())
1538 return null;
1539
1540 ConstructorRepository typeInfo = ConstructorRepository.make(enclosingInfo.getDescriptor(),
1541 getFactory());
1542 Type [] parameterTypes = typeInfo.getParameterTypes();
1543 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length];
1544
1545 // Convert Types to Classes; returned types *should*
1546 // be class objects since the methodDescriptor's used
1547 // don't have generics information
1548 for(int i = 0; i < parameterClasses.length; i++)
1549 parameterClasses[i] = toClass(parameterTypes[i]);
1550
1551 // Perform access check
1552 final Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass();
1553 @SuppressWarnings("removal")
1554 SecurityManager sm = System.getSecurityManager();
1555 if (sm != null) {
1556 enclosingCandidate.checkMemberAccess(sm, Member.DECLARED,
1557 Reflection.getCallerClass(), true);
1558 }
1559
1560 Constructor<?>[] candidates = enclosingCandidate
1561 .privateGetDeclaredConstructors(false);
1562 /*
1563 * Loop over all declared constructors; match number
1564 * of and type of parameters.
1565 */
1566 ReflectionFactory fact = getReflectionFactory();
1567 for (Constructor<?> c : candidates) {
1568 if (arrayContentsEq(parameterClasses,
1569 fact.getExecutableSharedParameterTypes(c))) {
1570 return fact.copyConstructor(c);
1571 }
1572 }
1573
1574 throw new InternalError("Enclosing constructor not found");
1575 }
1576 }
1577
1578
1579 /**
1580 * If the class or interface represented by this {@code Class} object
1581 * is a member of another class, returns the {@code Class} object
1582 * representing the class in which it was declared. This method returns
1583 * null if this class or interface is not a member of any other class. If
1584 * this {@code Class} object represents an array class, a primitive
1585 * type, or void, then this method returns null.
1586 *
1587 * @return the declaring class for this class
1588 * @throws SecurityException
1589 * If a security manager, <i>s</i>, is present and the caller's
1590 * class loader is not the same as or an ancestor of the class
1591 * loader for the declaring class and invocation of {@link
1592 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
1593 * denies access to the package of the declaring class
1594 * @since 1.1
1595 */
1596 @CallerSensitive
1597 public Class<?> getDeclaringClass() throws SecurityException {
1598 final Class<?> candidate = getDeclaringClass0();
1599
1600 if (candidate != null) {
1601 @SuppressWarnings("removal")
1602 SecurityManager sm = System.getSecurityManager();
1603 if (sm != null) {
1604 candidate.checkPackageAccess(sm,
1605 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
1606 }
1607 }
1608 return candidate;
1609 }
1610
1611 private native Class<?> getDeclaringClass0();
1612
1613
1614 /**
1615 * Returns the immediately enclosing class of the underlying
1616 * class. If the underlying class is a top level class this
1617 * method returns {@code null}.
1618 * @return the immediately enclosing class of the underlying class
1619 * @throws SecurityException
1620 * If a security manager, <i>s</i>, is present and the caller's
1621 * class loader is not the same as or an ancestor of the class
1622 * loader for the enclosing class and invocation of {@link
1623 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
1624 * denies access to the package of the enclosing class
1625 * @since 1.5
1626 */
1627 @CallerSensitive
1628 public Class<?> getEnclosingClass() throws SecurityException {
1629 // There are five kinds of classes (or interfaces):
1630 // a) Top level classes
1631 // b) Nested classes (static member classes)
1632 // c) Inner classes (non-static member classes)
1633 // d) Local classes (named classes declared within a method)
1634 // e) Anonymous classes
1635
1636
1637 // JVM Spec 4.7.7: A class must have an EnclosingMethod
1638 // attribute if and only if it is a local class or an
1639 // anonymous class.
1640 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1641 Class<?> enclosingCandidate;
1642
1643 if (enclosingInfo == null) {
1644 // This is a top level or a nested class or an inner class (a, b, or c)
1645 enclosingCandidate = getDeclaringClass0();
1646 } else {
1647 Class<?> enclosingClass = enclosingInfo.getEnclosingClass();
1648 // This is a local class or an anonymous class (d or e)
1649 if (enclosingClass == this || enclosingClass == null)
1650 throw new InternalError("Malformed enclosing method information");
1651 else
1652 enclosingCandidate = enclosingClass;
1653 }
1654
1655 if (enclosingCandidate != null) {
1656 @SuppressWarnings("removal")
1657 SecurityManager sm = System.getSecurityManager();
1658 if (sm != null) {
1659 enclosingCandidate.checkPackageAccess(sm,
1660 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
1661 }
1662 }
1663 return enclosingCandidate;
1664 }
1665
1666 /**
1667 * Returns the simple name of the underlying class as given in the
1668 * source code. An empty string is returned if the underlying class is
1669 * {@linkplain #isAnonymousClass() anonymous}.
1670 * A {@linkplain #isSynthetic() synthetic class}, one not present
1671 * in source code, can have a non-empty name including special
1672 * characters, such as "{@code $}".
1673 *
1674 * <p>The simple name of an {@linkplain #isArray() array class} is the simple name of the
1675 * component type with "[]" appended. In particular the simple
1676 * name of an array class whose component type is anonymous is "[]".
1677 *
1678 * @return the simple name of the underlying class
1679 * @since 1.5
1680 */
1681 public String getSimpleName() {
1682 ReflectionData<T> rd = reflectionData();
1683 String simpleName = rd.simpleName;
1684 if (simpleName == null) {
1685 rd.simpleName = simpleName = getSimpleName0();
1686 }
1687 return simpleName;
1688 }
1689
1690 private String getSimpleName0() {
1691 if (isArray()) {
1692 return getComponentType().getSimpleName().concat("[]");
1693 }
1694 String simpleName = getSimpleBinaryName();
1695 if (simpleName == null) { // top level class
1696 simpleName = getName();
1697 simpleName = simpleName.substring(simpleName.lastIndexOf('.') + 1); // strip the package name
1698 }
1699 return simpleName;
1700 }
1701
1702 /**
1703 * Return an informative string for the name of this class or interface.
1704 *
1705 * @return an informative string for the name of this class or interface
1706 * @since 1.8
1707 */
1708 public String getTypeName() {
1709 if (isArray()) {
1710 try {
1711 Class<?> cl = this;
1712 int dimensions = 0;
1713 do {
1714 dimensions++;
1715 cl = cl.getComponentType();
1716 } while (cl.isArray());
1717 return cl.getName().concat("[]".repeat(dimensions));
1718 } catch (Throwable e) { /*FALLTHRU*/ }
1719 }
1720 return getName();
1721 }
1722
1723 /**
1724 * Returns the canonical name of the underlying class as
1725 * defined by <cite>The Java Language Specification</cite>.
1726 * Returns {@code null} if the underlying class does not have a canonical
1727 * name. Classes without canonical names include:
1728 * <ul>
1729 * <li>a {@linkplain #isLocalClass() local class}
1730 * <li>a {@linkplain #isAnonymousClass() anonymous class}
1731 * <li>a {@linkplain #isHidden() hidden class}
1732 * <li>an array whose component type does not have a canonical name</li>
1733 * </ul>
1734 *
1735 * The canonical name for a primitive class is the keyword for the
1736 * corresponding primitive type ({@code byte}, {@code short},
1737 * {@code char}, {@code int}, and so on).
1738 *
1739 * <p>An array type has a canonical name if and only if its
1740 * component type has a canonical name. When an array type has a
1741 * canonical name, it is equal to the canonical name of the
1742 * component type followed by "{@code []}".
1743 *
1744 * @return the canonical name of the underlying class if it exists, and
1745 * {@code null} otherwise.
1746 * @jls 6.7 Fully Qualified Names and Canonical Names
1747 * @since 1.5
1748 */
1749 public String getCanonicalName() {
1750 ReflectionData<T> rd = reflectionData();
1751 String canonicalName = rd.canonicalName;
1752 if (canonicalName == null) {
1753 rd.canonicalName = canonicalName = getCanonicalName0();
1754 }
1755 return canonicalName == ReflectionData.NULL_SENTINEL? null : canonicalName;
1756 }
1757
1758 private String getCanonicalName0() {
1759 if (isArray()) {
1760 String canonicalName = getComponentType().getCanonicalName();
1761 if (canonicalName != null)
1762 return canonicalName.concat("[]");
1763 else
1764 return ReflectionData.NULL_SENTINEL;
1765 }
1766 if (isHidden() || isLocalOrAnonymousClass())
1767 return ReflectionData.NULL_SENTINEL;
1768 Class<?> enclosingClass = getEnclosingClass();
1769 if (enclosingClass == null) { // top level class
1770 return getName();
1771 } else {
1772 String enclosingName = enclosingClass.getCanonicalName();
1773 if (enclosingName == null)
1774 return ReflectionData.NULL_SENTINEL;
1775 String simpleName = getSimpleName();
1776 return new StringBuilder(enclosingName.length() + simpleName.length() + 1)
1777 .append(enclosingName)
1778 .append('.')
1779 .append(simpleName)
1780 .toString();
1781 }
1782 }
1783
1784 /**
1785 * Returns {@code true} if and only if the underlying class
1786 * is an anonymous class.
1787 *
1788 * @apiNote
1789 * An anonymous class is not a {@linkplain #isHidden() hidden class}.
1790 *
1791 * @return {@code true} if and only if this class is an anonymous class.
1792 * @since 1.5
1793 * @jls 15.9.5 Anonymous Class Declarations
1794 */
1795 public boolean isAnonymousClass() {
1796 return !isArray() && isLocalOrAnonymousClass() &&
1797 getSimpleBinaryName0() == null;
1798 }
1799
1800 /**
1801 * Returns {@code true} if and only if the underlying class
1802 * is a local class.
1803 *
1804 * @return {@code true} if and only if this class is a local class.
1805 * @since 1.5
1806 * @jls 14.3 Local Class Declarations
1807 */
1808 public boolean isLocalClass() {
1809 return isLocalOrAnonymousClass() &&
1810 (isArray() || getSimpleBinaryName0() != null);
1811 }
1812
1813 /**
1814 * Returns {@code true} if and only if the underlying class
1815 * is a member class.
1816 *
1817 * @return {@code true} if and only if this class is a member class.
1818 * @since 1.5
1819 * @jls 8.5 Member Type Declarations
1820 */
1821 public boolean isMemberClass() {
1822 return !isLocalOrAnonymousClass() && getDeclaringClass0() != null;
1823 }
1824
1825 /**
1826 * Returns the "simple binary name" of the underlying class, i.e.,
1827 * the binary name without the leading enclosing class name.
1828 * Returns {@code null} if the underlying class is a top level
1829 * class.
1830 */
1831 private String getSimpleBinaryName() {
1832 if (isTopLevelClass())
1833 return null;
1834 String name = getSimpleBinaryName0();
1835 if (name == null) // anonymous class
1836 return "";
1837 return name;
1838 }
1839
1840 private native String getSimpleBinaryName0();
1841
1842 /**
1843 * Returns {@code true} if this is a top level class. Returns {@code false}
1844 * otherwise.
1845 */
1846 private boolean isTopLevelClass() {
1847 return !isLocalOrAnonymousClass() && getDeclaringClass0() == null;
1848 }
1849
1850 /**
1851 * Returns {@code true} if this is a local class or an anonymous
1852 * class. Returns {@code false} otherwise.
1853 */
1854 private boolean isLocalOrAnonymousClass() {
1855 // JVM Spec 4.7.7: A class must have an EnclosingMethod
1856 // attribute if and only if it is a local class or an
1857 // anonymous class.
1858 return hasEnclosingMethodInfo();
1859 }
1860
1861 private boolean hasEnclosingMethodInfo() {
1862 Object[] enclosingInfo = getEnclosingMethod0();
1863 if (enclosingInfo != null) {
1864 EnclosingMethodInfo.validate(enclosingInfo);
1865 return true;
1866 }
1867 return false;
1868 }
1869
1870 /**
1871 * Returns an array containing {@code Class} objects representing all
1872 * the public classes and interfaces that are members of the class
1873 * represented by this {@code Class} object. This includes public
1874 * class and interface members inherited from superclasses and public class
1875 * and interface members declared by the class. This method returns an
1876 * array of length 0 if this {@code Class} object has no public member
1877 * classes or interfaces. This method also returns an array of length 0 if
1878 * this {@code Class} object represents a primitive type, an array
1879 * class, or void.
1880 *
1881 * @return the array of {@code Class} objects representing the public
1882 * members of this class
1883 * @throws SecurityException
1884 * If a security manager, <i>s</i>, is present and
1885 * the caller's class loader is not the same as or an
1886 * ancestor of the class loader for the current class and
1887 * invocation of {@link SecurityManager#checkPackageAccess
1888 * s.checkPackageAccess()} denies access to the package
1889 * of this class.
1890 *
1891 * @since 1.1
1892 */
1893 @SuppressWarnings("removal")
1894 @CallerSensitive
1895 public Class<?>[] getClasses() {
1896 SecurityManager sm = System.getSecurityManager();
1897 if (sm != null) {
1898 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), false);
1899 }
1900
1901 // Privileged so this implementation can look at DECLARED classes,
1902 // something the caller might not have privilege to do. The code here
1903 // is allowed to look at DECLARED classes because (1) it does not hand
1904 // out anything other than public members and (2) public member access
1905 // has already been ok'd by the SecurityManager.
1906
1907 return java.security.AccessController.doPrivileged(
1908 new java.security.PrivilegedAction<>() {
1909 public Class<?>[] run() {
1910 List<Class<?>> list = new ArrayList<>();
1911 Class<?> currentClass = Class.this;
1912 while (currentClass != null) {
1913 for (Class<?> m : currentClass.getDeclaredClasses()) {
1914 if (Modifier.isPublic(m.getModifiers())) {
1915 list.add(m);
1916 }
1917 }
1918 currentClass = currentClass.getSuperclass();
1919 }
1920 return list.toArray(new Class<?>[0]);
1921 }
1922 });
1923 }
1924
1925
1926 /**
1927 * Returns an array containing {@code Field} objects reflecting all
1928 * the accessible public fields of the class or interface represented by
1929 * this {@code Class} object.
1930 *
1931 * <p> If this {@code Class} object represents a class or interface with
1932 * no accessible public fields, then this method returns an array of length
1933 * 0.
1934 *
1935 * <p> If this {@code Class} object represents a class, then this method
1936 * returns the public fields of the class and of all its superclasses and
1937 * superinterfaces.
1938 *
1939 * <p> If this {@code Class} object represents an interface, then this
1940 * method returns the fields of the interface and of all its
1941 * superinterfaces.
1942 *
1943 * <p> If this {@code Class} object represents an array type, a primitive
1944 * type, or void, then this method returns an array of length 0.
1945 *
1946 * <p> The elements in the returned array are not sorted and are not in any
1947 * particular order.
1948 *
1949 * @return the array of {@code Field} objects representing the
1950 * public fields
1951 * @throws SecurityException
1952 * If a security manager, <i>s</i>, is present and
1953 * the caller's class loader is not the same as or an
1954 * ancestor of the class loader for the current class and
1955 * invocation of {@link SecurityManager#checkPackageAccess
1956 * s.checkPackageAccess()} denies access to the package
1957 * of this class.
1958 *
1959 * @since 1.1
1960 * @jls 8.2 Class Members
1961 * @jls 8.3 Field Declarations
1962 */
1963 @CallerSensitive
1964 public Field[] getFields() throws SecurityException {
1965 @SuppressWarnings("removal")
1966 SecurityManager sm = System.getSecurityManager();
1967 if (sm != null) {
1968 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
1969 }
1970 return copyFields(privateGetPublicFields());
1971 }
1972
1973
1974 /**
1975 * Returns an array containing {@code Method} objects reflecting all the
1976 * public methods of the class or interface represented by this {@code
1977 * Class} object, including those declared by the class or interface and
1978 * those inherited from superclasses and superinterfaces.
1979 *
1980 * <p> If this {@code Class} object represents an array type, then the
1981 * returned array has a {@code Method} object for each of the public
1982 * methods inherited by the array type from {@code Object}. It does not
1983 * contain a {@code Method} object for {@code clone()}.
1984 *
1985 * <p> If this {@code Class} object represents an interface then the
1986 * returned array does not contain any implicitly declared methods from
1987 * {@code Object}. Therefore, if no methods are explicitly declared in
1988 * this interface or any of its superinterfaces then the returned array
1989 * has length 0. (Note that a {@code Class} object which represents a class
1990 * always has public methods, inherited from {@code Object}.)
1991 *
1992 * <p> The returned array never contains methods with names "{@code <init>}"
1993 * or "{@code <clinit>}".
1994 *
1995 * <p> The elements in the returned array are not sorted and are not in any
1996 * particular order.
1997 *
1998 * <p> Generally, the result is computed as with the following 4 step algorithm.
1999 * Let C be the class or interface represented by this {@code Class} object:
2000 * <ol>
2001 * <li> A union of methods is composed of:
2002 * <ol type="a">
2003 * <li> C's declared public instance and static methods as returned by
2004 * {@link #getDeclaredMethods()} and filtered to include only public
2005 * methods.</li>
2006 * <li> If C is a class other than {@code Object}, then include the result
2007 * of invoking this algorithm recursively on the superclass of C.</li>
2008 * <li> Include the results of invoking this algorithm recursively on all
2009 * direct superinterfaces of C, but include only instance methods.</li>
2010 * </ol></li>
2011 * <li> Union from step 1 is partitioned into subsets of methods with same
2012 * signature (name, parameter types) and return type.</li>
2013 * <li> Within each such subset only the most specific methods are selected.
2014 * Let method M be a method from a set of methods with same signature
2015 * and return type. M is most specific if there is no such method
2016 * N != M from the same set, such that N is more specific than M.
2017 * N is more specific than M if:
2018 * <ol type="a">
2019 * <li> N is declared by a class and M is declared by an interface; or</li>
2020 * <li> N and M are both declared by classes or both by interfaces and
2021 * N's declaring type is the same as or a subtype of M's declaring type
2022 * (clearly, if M's and N's declaring types are the same type, then
2023 * M and N are the same method).</li>
2024 * </ol></li>
2025 * <li> The result of this algorithm is the union of all selected methods from
2026 * step 3.</li>
2027 * </ol>
2028 *
2029 * @apiNote There may be more than one method with a particular name
2030 * and parameter types in a class because while the Java language forbids a
2031 * class to declare multiple methods with the same signature but different
2032 * return types, the Java virtual machine does not. This
2033 * increased flexibility in the virtual machine can be used to
2034 * implement various language features. For example, covariant
2035 * returns can be implemented with {@linkplain
2036 * java.lang.reflect.Method#isBridge bridge methods}; the bridge
2037 * method and the overriding method would have the same
2038 * signature but different return types.
2039 *
2040 * @return the array of {@code Method} objects representing the
2041 * public methods of this class
2042 * @throws SecurityException
2043 * If a security manager, <i>s</i>, is present and
2044 * the caller's class loader is not the same as or an
2045 * ancestor of the class loader for the current class and
2046 * invocation of {@link SecurityManager#checkPackageAccess
2047 * s.checkPackageAccess()} denies access to the package
2048 * of this class.
2049 *
2050 * @jls 8.2 Class Members
2051 * @jls 8.4 Method Declarations
2052 * @since 1.1
2053 */
2054 @CallerSensitive
2055 public Method[] getMethods() throws SecurityException {
2056 @SuppressWarnings("removal")
2057 SecurityManager sm = System.getSecurityManager();
2058 if (sm != null) {
2059 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2060 }
2061 return copyMethods(privateGetPublicMethods());
2062 }
2063
2064
2065 /**
2066 * Returns an array containing {@code Constructor} objects reflecting
2067 * all the public constructors of the class represented by this
2068 * {@code Class} object. An array of length 0 is returned if the
2069 * class has no public constructors, or if the class is an array class, or
2070 * if the class reflects a primitive type or void.
2071 *
2072 * @apiNote
2073 * While this method returns an array of {@code
2074 * Constructor<T>} objects (that is an array of constructors from
2075 * this class), the return type of this method is {@code
2076 * Constructor<?>[]} and <em>not</em> {@code Constructor<T>[]} as
2077 * might be expected. This less informative return type is
2078 * necessary since after being returned from this method, the
2079 * array could be modified to hold {@code Constructor} objects for
2080 * different classes, which would violate the type guarantees of
2081 * {@code Constructor<T>[]}.
2082 *
2083 * @return the array of {@code Constructor} objects representing the
2084 * public constructors of this class
2085 * @throws SecurityException
2086 * If a security manager, <i>s</i>, is present and
2087 * the caller's class loader is not the same as or an
2088 * ancestor of the class loader for the current class and
2089 * invocation of {@link SecurityManager#checkPackageAccess
2090 * s.checkPackageAccess()} denies access to the package
2091 * of this class.
2092 *
2093 * @see #getDeclaredConstructors()
2094 * @since 1.1
2095 */
2096 @CallerSensitive
2097 public Constructor<?>[] getConstructors() throws SecurityException {
2098 @SuppressWarnings("removal")
2099 SecurityManager sm = System.getSecurityManager();
2100 if (sm != null) {
2101 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2102 }
2103 return copyConstructors(privateGetDeclaredConstructors(true));
2104 }
2105
2106
2107 /**
2108 * Returns a {@code Field} object that reflects the specified public member
2109 * field of the class or interface represented by this {@code Class}
2110 * object. The {@code name} parameter is a {@code String} specifying the
2111 * simple name of the desired field.
2112 *
2113 * <p> The field to be reflected is determined by the algorithm that
2114 * follows. Let C be the class or interface represented by this {@code Class} object:
2115 *
2116 * <OL>
2117 * <LI> If C declares a public field with the name specified, that is the
2118 * field to be reflected.</LI>
2119 * <LI> If no field was found in step 1 above, this algorithm is applied
2120 * recursively to each direct superinterface of C. The direct
2121 * superinterfaces are searched in the order they were declared.</LI>
2122 * <LI> If no field was found in steps 1 and 2 above, and C has a
2123 * superclass S, then this algorithm is invoked recursively upon S.
2124 * If C has no superclass, then a {@code NoSuchFieldException}
2125 * is thrown.</LI>
2126 * </OL>
2127 *
2128 * <p> If this {@code Class} object represents an array type, then this
2129 * method does not find the {@code length} field of the array type.
2130 *
2131 * @param name the field name
2132 * @return the {@code Field} object of this class specified by
2133 * {@code name}
2134 * @throws NoSuchFieldException if a field with the specified name is
2135 * not found.
2136 * @throws NullPointerException if {@code name} is {@code null}
2137 * @throws SecurityException
2138 * If a security manager, <i>s</i>, is present and
2139 * the caller's class loader is not the same as or an
2140 * ancestor of the class loader for the current class and
2141 * invocation of {@link SecurityManager#checkPackageAccess
2142 * s.checkPackageAccess()} denies access to the package
2143 * of this class.
2144 *
2145 * @since 1.1
2146 * @jls 8.2 Class Members
2147 * @jls 8.3 Field Declarations
2148 */
2149 @CallerSensitive
2150 public Field getField(String name)
2151 throws NoSuchFieldException, SecurityException {
2152 Objects.requireNonNull(name);
2153 @SuppressWarnings("removal")
2154 SecurityManager sm = System.getSecurityManager();
2155 if (sm != null) {
2156 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2157 }
2158 Field field = getField0(name);
2159 if (field == null) {
2160 throw new NoSuchFieldException(name);
2161 }
2162 return getReflectionFactory().copyField(field);
2163 }
2164
2165
2166 /**
2167 * Returns a {@code Method} object that reflects the specified public
2168 * member method of the class or interface represented by this
2169 * {@code Class} object. The {@code name} parameter is a
2170 * {@code String} specifying the simple name of the desired method. The
2171 * {@code parameterTypes} parameter is an array of {@code Class}
2172 * objects that identify the method's formal parameter types, in declared
2173 * order. If {@code parameterTypes} is {@code null}, it is
2174 * treated as if it were an empty array.
2175 *
2176 * <p> If this {@code Class} object represents an array type, then this
2177 * method finds any public method inherited by the array type from
2178 * {@code Object} except method {@code clone()}.
2179 *
2180 * <p> If this {@code Class} object represents an interface then this
2181 * method does not find any implicitly declared method from
2182 * {@code Object}. Therefore, if no methods are explicitly declared in
2183 * this interface or any of its superinterfaces, then this method does not
2184 * find any method.
2185 *
2186 * <p> This method does not find any method with name "{@code <init>}" or
2187 * "{@code <clinit>}".
2188 *
2189 * <p> Generally, the method to be reflected is determined by the 4 step
2190 * algorithm that follows.
2191 * Let C be the class or interface represented by this {@code Class} object:
2192 * <ol>
2193 * <li> A union of methods is composed of:
2194 * <ol type="a">
2195 * <li> C's declared public instance and static methods as returned by
2196 * {@link #getDeclaredMethods()} and filtered to include only public
2197 * methods that match given {@code name} and {@code parameterTypes}</li>
2198 * <li> If C is a class other than {@code Object}, then include the result
2199 * of invoking this algorithm recursively on the superclass of C.</li>
2200 * <li> Include the results of invoking this algorithm recursively on all
2201 * direct superinterfaces of C, but include only instance methods.</li>
2202 * </ol></li>
2203 * <li> This union is partitioned into subsets of methods with same
2204 * return type (the selection of methods from step 1 also guarantees that
2205 * they have the same method name and parameter types).</li>
2206 * <li> Within each such subset only the most specific methods are selected.
2207 * Let method M be a method from a set of methods with same VM
2208 * signature (return type, name, parameter types).
2209 * M is most specific if there is no such method N != M from the same
2210 * set, such that N is more specific than M. N is more specific than M
2211 * if:
2212 * <ol type="a">
2213 * <li> N is declared by a class and M is declared by an interface; or</li>
2214 * <li> N and M are both declared by classes or both by interfaces and
2215 * N's declaring type is the same as or a subtype of M's declaring type
2216 * (clearly, if M's and N's declaring types are the same type, then
2217 * M and N are the same method).</li>
2218 * </ol></li>
2219 * <li> The result of this algorithm is chosen arbitrarily from the methods
2220 * with most specific return type among all selected methods from step 3.
2221 * Let R be a return type of a method M from the set of all selected methods
2222 * from step 3. M is a method with most specific return type if there is
2223 * no such method N != M from the same set, having return type S != R,
2224 * such that S is a subtype of R as determined by
2225 * R.class.{@link #isAssignableFrom}(S.class).
2226 * </ol>
2227 *
2228 * @apiNote There may be more than one method with matching name and
2229 * parameter types in a class because while the Java language forbids a
2230 * class to declare multiple methods with the same signature but different
2231 * return types, the Java virtual machine does not. This
2232 * increased flexibility in the virtual machine can be used to
2233 * implement various language features. For example, covariant
2234 * returns can be implemented with {@linkplain
2235 * java.lang.reflect.Method#isBridge bridge methods}; the bridge
2236 * method and the overriding method would have the same
2237 * signature but different return types. This method would return the
2238 * overriding method as it would have a more specific return type.
2239 *
2240 * @param name the name of the method
2241 * @param parameterTypes the list of parameters
2242 * @return the {@code Method} object that matches the specified
2243 * {@code name} and {@code parameterTypes}
2244 * @throws NoSuchMethodException if a matching method is not found
2245 * or if the name is "<init>"or "<clinit>".
2246 * @throws NullPointerException if {@code name} is {@code null}
2247 * @throws SecurityException
2248 * If a security manager, <i>s</i>, is present and
2249 * the caller's class loader is not the same as or an
2250 * ancestor of the class loader for the current class and
2251 * invocation of {@link SecurityManager#checkPackageAccess
2252 * s.checkPackageAccess()} denies access to the package
2253 * of this class.
2254 *
2255 * @jls 8.2 Class Members
2256 * @jls 8.4 Method Declarations
2257 * @since 1.1
2258 */
2259 @CallerSensitive
2260 public Method getMethod(String name, Class<?>... parameterTypes)
2261 throws NoSuchMethodException, SecurityException {
2262 Objects.requireNonNull(name);
2263 @SuppressWarnings("removal")
2264 SecurityManager sm = System.getSecurityManager();
2265 if (sm != null) {
2266 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2267 }
2268 Method method = getMethod0(name, parameterTypes);
2269 if (method == null) {
2270 throw new NoSuchMethodException(methodToString(name, parameterTypes));
2271 }
2272 return getReflectionFactory().copyMethod(method);
2273 }
2274
2275 /**
2276 * Returns a {@code Constructor} object that reflects the specified
2277 * public constructor of the class represented by this {@code Class}
2278 * object. The {@code parameterTypes} parameter is an array of
2279 * {@code Class} objects that identify the constructor's formal
2280 * parameter types, in declared order.
2281 *
2282 * If this {@code Class} object represents an inner class
2283 * declared in a non-static context, the formal parameter types
2284 * include the explicit enclosing instance as the first parameter.
2285 *
2286 * <p> The constructor to reflect is the public constructor of the class
2287 * represented by this {@code Class} object whose formal parameter
2288 * types match those specified by {@code parameterTypes}.
2289 *
2290 * @param parameterTypes the parameter array
2291 * @return the {@code Constructor} object of the public constructor that
2292 * matches the specified {@code parameterTypes}
2293 * @throws NoSuchMethodException if a matching constructor is not found,
2294 * including when this {@code Class} object represents
2295 * an interface, a primitive type, an array class, or void.
2296 * @throws SecurityException
2297 * If a security manager, <i>s</i>, is present and
2298 * the caller's class loader is not the same as or an
2299 * ancestor of the class loader for the current class and
2300 * invocation of {@link SecurityManager#checkPackageAccess
2301 * s.checkPackageAccess()} denies access to the package
2302 * of this class.
2303 *
2304 * @see #getDeclaredConstructor(Class<?>[])
2305 * @since 1.1
2306 */
2307 @CallerSensitive
2308 public Constructor<T> getConstructor(Class<?>... parameterTypes)
2309 throws NoSuchMethodException, SecurityException
2310 {
2311 @SuppressWarnings("removal")
2312 SecurityManager sm = System.getSecurityManager();
2313 if (sm != null) {
2314 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2315 }
2316 return getReflectionFactory().copyConstructor(
2317 getConstructor0(parameterTypes, Member.PUBLIC));
2318 }
2319
2320
2321 /**
2322 * Returns an array of {@code Class} objects reflecting all the
2323 * classes and interfaces declared as members of the class represented by
2324 * this {@code Class} object. This includes public, protected, default
2325 * (package) access, and private classes and interfaces declared by the
2326 * class, but excludes inherited classes and interfaces. This method
2327 * returns an array of length 0 if the class declares no classes or
2328 * interfaces as members, or if this {@code Class} object represents a
2329 * primitive type, an array class, or void.
2330 *
2331 * @return the array of {@code Class} objects representing all the
2332 * declared members of this class
2333 * @throws SecurityException
2334 * If a security manager, <i>s</i>, is present and any of the
2335 * following conditions is met:
2336 *
2337 * <ul>
2338 *
2339 * <li> the caller's class loader is not the same as the
2340 * class loader of this class and invocation of
2341 * {@link SecurityManager#checkPermission
2342 * s.checkPermission} method with
2343 * {@code RuntimePermission("accessDeclaredMembers")}
2344 * denies access to the declared classes within this class
2345 *
2346 * <li> the caller's class loader is not the same as or an
2347 * ancestor of the class loader for the current class and
2348 * invocation of {@link SecurityManager#checkPackageAccess
2349 * s.checkPackageAccess()} denies access to the package
2350 * of this class
2351 *
2352 * </ul>
2353 *
2354 * @since 1.1
2355 * @jls 8.5 Member Type Declarations
2356 */
2357 @CallerSensitive
2358 public Class<?>[] getDeclaredClasses() throws SecurityException {
2359 @SuppressWarnings("removal")
2360 SecurityManager sm = System.getSecurityManager();
2361 if (sm != null) {
2362 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), false);
2363 }
2364 return getDeclaredClasses0();
2365 }
2366
2367
2368 /**
2369 * Returns an array of {@code Field} objects reflecting all the fields
2370 * declared by the class or interface represented by this
2371 * {@code Class} object. This includes public, protected, default
2372 * (package) access, and private fields, but excludes inherited fields.
2373 *
2374 * <p> If this {@code Class} object represents a class or interface with no
2375 * declared fields, then this method returns an array of length 0.
2376 *
2377 * <p> If this {@code Class} object represents an array type, a primitive
2378 * type, or void, then this method returns an array of length 0.
2379 *
2380 * <p> The elements in the returned array are not sorted and are not in any
2381 * particular order.
2382 *
2383 * @return the array of {@code Field} objects representing all the
2384 * declared fields of this class
2385 * @throws SecurityException
2386 * If a security manager, <i>s</i>, is present and any of the
2387 * following conditions is met:
2388 *
2389 * <ul>
2390 *
2391 * <li> the caller's class loader is not the same as the
2392 * class loader of this class and invocation of
2393 * {@link SecurityManager#checkPermission
2394 * s.checkPermission} method with
2395 * {@code RuntimePermission("accessDeclaredMembers")}
2396 * denies access to the declared fields within this class
2397 *
2398 * <li> the caller's class loader is not the same as or an
2399 * ancestor of the class loader for the current class and
2400 * invocation of {@link SecurityManager#checkPackageAccess
2401 * s.checkPackageAccess()} denies access to the package
2402 * of this class
2403 *
2404 * </ul>
2405 *
2406 * @since 1.1
2407 * @jls 8.2 Class Members
2408 * @jls 8.3 Field Declarations
2409 */
2410 @CallerSensitive
2411 public Field[] getDeclaredFields() throws SecurityException {
2412 @SuppressWarnings("removal")
2413 SecurityManager sm = System.getSecurityManager();
2414 if (sm != null) {
2415 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2416 }
2417 return copyFields(privateGetDeclaredFields(false));
2418 }
2419
2420 /**
2421 * Returns an array of {@code RecordComponent} objects representing all the
2422 * record components of this record class, or {@code null} if this class is
2423 * not a record class.
2424 *
2425 * <p> The components are returned in the same order that they are declared
2426 * in the record header. The array is empty if this record class has no
2427 * components. If the class is not a record class, that is {@link
2428 * #isRecord()} returns {@code false}, then this method returns {@code null}.
2429 * Conversely, if {@link #isRecord()} returns {@code true}, then this method
2430 * returns a non-null value.
2431 *
2432 * @apiNote
2433 * <p> The following method can be used to find the record canonical constructor:
2434 *
2435 * <pre>{@code
2436 * static <T extends Record> Constructor<T> getCanonicalConstructor(Class<T> cls)
2437 * throws NoSuchMethodException {
2438 * Class<?>[] paramTypes =
2439 * Arrays.stream(cls.getRecordComponents())
2440 * .map(RecordComponent::getType)
2441 * .toArray(Class<?>[]::new);
2442 * return cls.getDeclaredConstructor(paramTypes);
2443 * }}</pre>
2444 *
2445 * @return An array of {@code RecordComponent} objects representing all the
2446 * record components of this record class, or {@code null} if this
2447 * class is not a record class
2448 * @throws SecurityException
2449 * If a security manager, <i>s</i>, is present and any of the
2450 * following conditions is met:
2451 *
2452 * <ul>
2453 *
2454 * <li> the caller's class loader is not the same as the
2455 * class loader of this class and invocation of
2456 * {@link SecurityManager#checkPermission
2457 * s.checkPermission} method with
2458 * {@code RuntimePermission("accessDeclaredMembers")}
2459 * denies access to the declared methods within this class
2460 *
2461 * <li> the caller's class loader is not the same as or an
2462 * ancestor of the class loader for the current class and
2463 * invocation of {@link SecurityManager#checkPackageAccess
2464 * s.checkPackageAccess()} denies access to the package
2465 * of this class
2466 *
2467 * </ul>
2468 *
2469 * @jls 8.10 Record Classes
2470 * @since 16
2471 */
2472 @CallerSensitive
2473 public RecordComponent[] getRecordComponents() {
2474 @SuppressWarnings("removal")
2475 SecurityManager sm = System.getSecurityManager();
2476 if (sm != null) {
2477 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2478 }
2479 if (!isRecord()) {
2480 return null;
2481 }
2482 return getRecordComponents0();
2483 }
2484
2485 /**
2486 * Returns an array containing {@code Method} objects reflecting all the
2487 * declared methods of the class or interface represented by this {@code
2488 * Class} object, including public, protected, default (package)
2489 * access, and private methods, but excluding inherited methods.
2490 * The declared methods may include methods <em>not</em> in the
2491 * source of the class or interface, including {@linkplain
2492 * Method#isBridge bridge methods} and other {@linkplain
2493 * Executable#isSynthetic synthetic} methods added by compilers.
2494 *
2495 * <p> If this {@code Class} object represents a class or interface that
2496 * has multiple declared methods with the same name and parameter types,
2497 * but different return types, then the returned array has a {@code Method}
2498 * object for each such method.
2499 *
2500 * <p> If this {@code Class} object represents a class or interface that
2501 * has a class initialization method {@code <clinit>}, then the returned
2502 * array does <em>not</em> have a corresponding {@code Method} object.
2503 *
2504 * <p> If this {@code Class} object represents a class or interface with no
2505 * declared methods, then the returned array has length 0.
2506 *
2507 * <p> If this {@code Class} object represents an array type, a primitive
2508 * type, or void, then the returned array has length 0.
2509 *
2510 * <p> The elements in the returned array are not sorted and are not in any
2511 * particular order.
2512 *
2513 * @return the array of {@code Method} objects representing all the
2514 * declared methods of this class
2515 * @throws SecurityException
2516 * If a security manager, <i>s</i>, is present and any of the
2517 * following conditions is met:
2518 *
2519 * <ul>
2520 *
2521 * <li> the caller's class loader is not the same as the
2522 * class loader of this class and invocation of
2523 * {@link SecurityManager#checkPermission
2524 * s.checkPermission} method with
2525 * {@code RuntimePermission("accessDeclaredMembers")}
2526 * denies access to the declared methods within this class
2527 *
2528 * <li> the caller's class loader is not the same as or an
2529 * ancestor of the class loader for the current class and
2530 * invocation of {@link SecurityManager#checkPackageAccess
2531 * s.checkPackageAccess()} denies access to the package
2532 * of this class
2533 *
2534 * </ul>
2535 *
2536 * @jls 8.2 Class Members
2537 * @jls 8.4 Method Declarations
2538 * @see <a
2539 * href="{@docRoot}/java.base/java/lang/reflect/package-summary.html#LanguageJvmModel">Java
2540 * programming language and JVM modeling in core reflection</a>
2541 * @since 1.1
2542 */
2543 @CallerSensitive
2544 public Method[] getDeclaredMethods() throws SecurityException {
2545 @SuppressWarnings("removal")
2546 SecurityManager sm = System.getSecurityManager();
2547 if (sm != null) {
2548 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2549 }
2550 return copyMethods(privateGetDeclaredMethods(false));
2551 }
2552
2553 /**
2554 * Returns an array of {@code Constructor} objects reflecting all the
2555 * constructors implicitly or explicitly declared by the class represented by this
2556 * {@code Class} object. These are public, protected, default
2557 * (package) access, and private constructors. The elements in the array
2558 * returned are not sorted and are not in any particular order. If the
2559 * class has a default constructor (JLS {@jls 8.8.9}), it is included in the returned array.
2560 * If a record class has a canonical constructor (JLS {@jls
2561 * 8.10.4.1}, {@jls 8.10.4.2}), it is included in the returned array.
2562 *
2563 * This method returns an array of length 0 if this {@code Class}
2564 * object represents an interface, a primitive type, an array class, or
2565 * void.
2566 *
2567 * @return the array of {@code Constructor} objects representing all the
2568 * declared constructors of this class
2569 * @throws SecurityException
2570 * If a security manager, <i>s</i>, is present and any of the
2571 * following conditions is met:
2572 *
2573 * <ul>
2574 *
2575 * <li> the caller's class loader is not the same as the
2576 * class loader of this class and invocation of
2577 * {@link SecurityManager#checkPermission
2578 * s.checkPermission} method with
2579 * {@code RuntimePermission("accessDeclaredMembers")}
2580 * denies access to the declared constructors within this class
2581 *
2582 * <li> the caller's class loader is not the same as or an
2583 * ancestor of the class loader for the current class and
2584 * invocation of {@link SecurityManager#checkPackageAccess
2585 * s.checkPackageAccess()} denies access to the package
2586 * of this class
2587 *
2588 * </ul>
2589 *
2590 * @since 1.1
2591 * @see #getConstructors()
2592 * @jls 8.8 Constructor Declarations
2593 */
2594 @CallerSensitive
2595 public Constructor<?>[] getDeclaredConstructors() throws SecurityException {
2596 @SuppressWarnings("removal")
2597 SecurityManager sm = System.getSecurityManager();
2598 if (sm != null) {
2599 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2600 }
2601 return copyConstructors(privateGetDeclaredConstructors(false));
2602 }
2603
2604
2605 /**
2606 * Returns a {@code Field} object that reflects the specified declared
2607 * field of the class or interface represented by this {@code Class}
2608 * object. The {@code name} parameter is a {@code String} that specifies
2609 * the simple name of the desired field.
2610 *
2611 * <p> If this {@code Class} object represents an array type, then this
2612 * method does not find the {@code length} field of the array type.
2613 *
2614 * @param name the name of the field
2615 * @return the {@code Field} object for the specified field in this
2616 * class
2617 * @throws NoSuchFieldException if a field with the specified name is
2618 * not found.
2619 * @throws NullPointerException if {@code name} is {@code null}
2620 * @throws SecurityException
2621 * If a security manager, <i>s</i>, is present and any of the
2622 * following conditions is met:
2623 *
2624 * <ul>
2625 *
2626 * <li> the caller's class loader is not the same as the
2627 * class loader of this class and invocation of
2628 * {@link SecurityManager#checkPermission
2629 * s.checkPermission} method with
2630 * {@code RuntimePermission("accessDeclaredMembers")}
2631 * denies access to the declared field
2632 *
2633 * <li> the caller's class loader is not the same as or an
2634 * ancestor of the class loader for the current class and
2635 * invocation of {@link SecurityManager#checkPackageAccess
2636 * s.checkPackageAccess()} denies access to the package
2637 * of this class
2638 *
2639 * </ul>
2640 *
2641 * @since 1.1
2642 * @jls 8.2 Class Members
2643 * @jls 8.3 Field Declarations
2644 */
2645 @CallerSensitive
2646 public Field getDeclaredField(String name)
2647 throws NoSuchFieldException, SecurityException {
2648 Objects.requireNonNull(name);
2649 @SuppressWarnings("removal")
2650 SecurityManager sm = System.getSecurityManager();
2651 if (sm != null) {
2652 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2653 }
2654 Field field = searchFields(privateGetDeclaredFields(false), name);
2655 if (field == null) {
2656 throw new NoSuchFieldException(name);
2657 }
2658 return getReflectionFactory().copyField(field);
2659 }
2660
2661
2662 /**
2663 * Returns a {@code Method} object that reflects the specified
2664 * declared method of the class or interface represented by this
2665 * {@code Class} object. The {@code name} parameter is a
2666 * {@code String} that specifies the simple name of the desired
2667 * method, and the {@code parameterTypes} parameter is an array of
2668 * {@code Class} objects that identify the method's formal parameter
2669 * types, in declared order. If more than one method with the same
2670 * parameter types is declared in a class, and one of these methods has a
2671 * return type that is more specific than any of the others, that method is
2672 * returned; otherwise one of the methods is chosen arbitrarily. If the
2673 * name is "<init>"or "<clinit>" a {@code NoSuchMethodException}
2674 * is raised.
2675 *
2676 * <p> If this {@code Class} object represents an array type, then this
2677 * method does not find the {@code clone()} method.
2678 *
2679 * @param name the name of the method
2680 * @param parameterTypes the parameter array
2681 * @return the {@code Method} object for the method of this class
2682 * matching the specified name and parameters
2683 * @throws NoSuchMethodException if a matching method is not found.
2684 * @throws NullPointerException if {@code name} is {@code null}
2685 * @throws SecurityException
2686 * If a security manager, <i>s</i>, is present and any of the
2687 * following conditions is met:
2688 *
2689 * <ul>
2690 *
2691 * <li> the caller's class loader is not the same as the
2692 * class loader of this class and invocation of
2693 * {@link SecurityManager#checkPermission
2694 * s.checkPermission} method with
2695 * {@code RuntimePermission("accessDeclaredMembers")}
2696 * denies access to the declared method
2697 *
2698 * <li> the caller's class loader is not the same as or an
2699 * ancestor of the class loader for the current class and
2700 * invocation of {@link SecurityManager#checkPackageAccess
2701 * s.checkPackageAccess()} denies access to the package
2702 * of this class
2703 *
2704 * </ul>
2705 *
2706 * @jls 8.2 Class Members
2707 * @jls 8.4 Method Declarations
2708 * @since 1.1
2709 */
2710 @CallerSensitive
2711 public Method getDeclaredMethod(String name, Class<?>... parameterTypes)
2712 throws NoSuchMethodException, SecurityException {
2713 Objects.requireNonNull(name);
2714 @SuppressWarnings("removal")
2715 SecurityManager sm = System.getSecurityManager();
2716 if (sm != null) {
2717 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2718 }
2719 Method method = searchMethods(privateGetDeclaredMethods(false), name, parameterTypes);
2720 if (method == null) {
2721 throw new NoSuchMethodException(methodToString(name, parameterTypes));
2722 }
2723 return getReflectionFactory().copyMethod(method);
2724 }
2725
2726 /**
2727 * Returns the list of {@code Method} objects for the declared public
2728 * methods of this class or interface that have the specified method name
2729 * and parameter types.
2730 *
2731 * @param name the name of the method
2732 * @param parameterTypes the parameter array
2733 * @return the list of {@code Method} objects for the public methods of
2734 * this class matching the specified name and parameters
2735 */
2736 List<Method> getDeclaredPublicMethods(String name, Class<?>... parameterTypes) {
2737 Method[] methods = privateGetDeclaredMethods(/* publicOnly */ true);
2738 ReflectionFactory factory = getReflectionFactory();
2739 List<Method> result = new ArrayList<>();
2740 for (Method method : methods) {
2741 if (method.getName().equals(name)
2742 && Arrays.equals(
2743 factory.getExecutableSharedParameterTypes(method),
2744 parameterTypes)) {
2745 result.add(factory.copyMethod(method));
2746 }
2747 }
2748 return result;
2749 }
2750
2751 /**
2752 * Returns a {@code Constructor} object that reflects the specified
2753 * constructor of the class represented by this
2754 * {@code Class} object. The {@code parameterTypes} parameter is
2755 * an array of {@code Class} objects that identify the constructor's
2756 * formal parameter types, in declared order.
2757 *
2758 * If this {@code Class} object represents an inner class
2759 * declared in a non-static context, the formal parameter types
2760 * include the explicit enclosing instance as the first parameter.
2761 *
2762 * @param parameterTypes the parameter array
2763 * @return The {@code Constructor} object for the constructor with the
2764 * specified parameter list
2765 * @throws NoSuchMethodException if a matching constructor is not found,
2766 * including when this {@code Class} object represents
2767 * an interface, a primitive type, an array class, or void.
2768 * @throws SecurityException
2769 * If a security manager, <i>s</i>, is present and any of the
2770 * following conditions is met:
2771 *
2772 * <ul>
2773 *
2774 * <li> the caller's class loader is not the same as the
2775 * class loader of this class and invocation of
2776 * {@link SecurityManager#checkPermission
2777 * s.checkPermission} method with
2778 * {@code RuntimePermission("accessDeclaredMembers")}
2779 * denies access to the declared constructor
2780 *
2781 * <li> the caller's class loader is not the same as or an
2782 * ancestor of the class loader for the current class and
2783 * invocation of {@link SecurityManager#checkPackageAccess
2784 * s.checkPackageAccess()} denies access to the package
2785 * of this class
2786 *
2787 * </ul>
2788 *
2789 * @see #getConstructor(Class<?>[])
2790 * @since 1.1
2791 */
2792 @CallerSensitive
2793 public Constructor<T> getDeclaredConstructor(Class<?>... parameterTypes)
2794 throws NoSuchMethodException, SecurityException
2795 {
2796 @SuppressWarnings("removal")
2797 SecurityManager sm = System.getSecurityManager();
2798 if (sm != null) {
2799 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2800 }
2801
2802 return getReflectionFactory().copyConstructor(
2803 getConstructor0(parameterTypes, Member.DECLARED));
2804 }
2805
2806 /**
2807 * Finds a resource with a given name.
2808 *
2809 * <p> If this class is in a named {@link Module Module} then this method
2810 * will attempt to find the resource in the module. This is done by
2811 * delegating to the module's class loader {@link
2812 * ClassLoader#findResource(String,String) findResource(String,String)}
2813 * method, invoking it with the module name and the absolute name of the
2814 * resource. Resources in named modules are subject to the rules for
2815 * encapsulation specified in the {@code Module} {@link
2816 * Module#getResourceAsStream getResourceAsStream} method and so this
2817 * method returns {@code null} when the resource is a
2818 * non-"{@code .class}" resource in a package that is not open to the
2819 * caller's module.
2820 *
2821 * <p> Otherwise, if this class is not in a named module then the rules for
2822 * searching resources associated with a given class are implemented by the
2823 * defining {@linkplain ClassLoader class loader} of the class. This method
2824 * delegates to this {@code Class} object's class loader.
2825 * If this {@code Class} object was loaded by the bootstrap class loader,
2826 * the method delegates to {@link ClassLoader#getSystemResourceAsStream}.
2827 *
2828 * <p> Before delegation, an absolute resource name is constructed from the
2829 * given resource name using this algorithm:
2830 *
2831 * <ul>
2832 *
2833 * <li> If the {@code name} begins with a {@code '/'}
2834 * (<code>'\u002f'</code>), then the absolute name of the resource is the
2835 * portion of the {@code name} following the {@code '/'}.
2836 *
2837 * <li> Otherwise, the absolute name is of the following form:
2838 *
2839 * <blockquote>
2840 * {@code modified_package_name/name}
2841 * </blockquote>
2842 *
2843 * <p> Where the {@code modified_package_name} is the package name of this
2844 * object with {@code '/'} substituted for {@code '.'}
2845 * (<code>'\u002e'</code>).
2846 *
2847 * </ul>
2848 *
2849 * @param name name of the desired resource
2850 * @return A {@link java.io.InputStream} object; {@code null} if no
2851 * resource with this name is found, the resource is in a package
2852 * that is not {@linkplain Module#isOpen(String, Module) open} to at
2853 * least the caller module, or access to the resource is denied
2854 * by the security manager.
2855 * @throws NullPointerException If {@code name} is {@code null}
2856 *
2857 * @see Module#getResourceAsStream(String)
2858 * @since 1.1
2859 * @revised 9
2860 */
2861 @CallerSensitive
2862 public InputStream getResourceAsStream(String name) {
2863 name = resolveName(name);
2864
2865 Module thisModule = getModule();
2866 if (thisModule.isNamed()) {
2867 // check if resource can be located by caller
2868 if (Resources.canEncapsulate(name)
2869 && !isOpenToCaller(name, Reflection.getCallerClass())) {
2870 return null;
2871 }
2872
2873 // resource not encapsulated or in package open to caller
2874 String mn = thisModule.getName();
2875 ClassLoader cl = classLoader;
2876 try {
2877
2878 // special-case built-in class loaders to avoid the
2879 // need for a URL connection
2880 if (cl == null) {
2881 return BootLoader.findResourceAsStream(mn, name);
2882 } else if (cl instanceof BuiltinClassLoader) {
2883 return ((BuiltinClassLoader) cl).findResourceAsStream(mn, name);
2884 } else {
2885 URL url = cl.findResource(mn, name);
2886 return (url != null) ? url.openStream() : null;
2887 }
2888
2889 } catch (IOException | SecurityException e) {
2890 return null;
2891 }
2892 }
2893
2894 // unnamed module
2895 ClassLoader cl = classLoader;
2896 if (cl == null) {
2897 return ClassLoader.getSystemResourceAsStream(name);
2898 } else {
2899 return cl.getResourceAsStream(name);
2900 }
2901 }
2902
2903 /**
2904 * Finds a resource with a given name.
2905 *
2906 * <p> If this class is in a named {@link Module Module} then this method
2907 * will attempt to find the resource in the module. This is done by
2908 * delegating to the module's class loader {@link
2909 * ClassLoader#findResource(String,String) findResource(String,String)}
2910 * method, invoking it with the module name and the absolute name of the
2911 * resource. Resources in named modules are subject to the rules for
2912 * encapsulation specified in the {@code Module} {@link
2913 * Module#getResourceAsStream getResourceAsStream} method and so this
2914 * method returns {@code null} when the resource is a
2915 * non-"{@code .class}" resource in a package that is not open to the
2916 * caller's module.
2917 *
2918 * <p> Otherwise, if this class is not in a named module then the rules for
2919 * searching resources associated with a given class are implemented by the
2920 * defining {@linkplain ClassLoader class loader} of the class. This method
2921 * delegates to this {@code Class} object's class loader.
2922 * If this {@code Class} object was loaded by the bootstrap class loader,
2923 * the method delegates to {@link ClassLoader#getSystemResource}.
2924 *
2925 * <p> Before delegation, an absolute resource name is constructed from the
2926 * given resource name using this algorithm:
2927 *
2928 * <ul>
2929 *
2930 * <li> If the {@code name} begins with a {@code '/'}
2931 * (<code>'\u002f'</code>), then the absolute name of the resource is the
2932 * portion of the {@code name} following the {@code '/'}.
2933 *
2934 * <li> Otherwise, the absolute name is of the following form:
2935 *
2936 * <blockquote>
2937 * {@code modified_package_name/name}
2938 * </blockquote>
2939 *
2940 * <p> Where the {@code modified_package_name} is the package name of this
2941 * object with {@code '/'} substituted for {@code '.'}
2942 * (<code>'\u002e'</code>).
2943 *
2944 * </ul>
2945 *
2946 * @param name name of the desired resource
2947 * @return A {@link java.net.URL} object; {@code null} if no resource with
2948 * this name is found, the resource cannot be located by a URL, the
2949 * resource is in a package that is not
2950 * {@linkplain Module#isOpen(String, Module) open} to at least the caller
2951 * module, or access to the resource is denied by the security
2952 * manager.
2953 * @throws NullPointerException If {@code name} is {@code null}
2954 * @since 1.1
2955 * @revised 9
2956 */
2957 @CallerSensitive
2958 public URL getResource(String name) {
2959 name = resolveName(name);
2960
2961 Module thisModule = getModule();
2962 if (thisModule.isNamed()) {
2963 // check if resource can be located by caller
2964 if (Resources.canEncapsulate(name)
2965 && !isOpenToCaller(name, Reflection.getCallerClass())) {
2966 return null;
2967 }
2968
2969 // resource not encapsulated or in package open to caller
2970 String mn = thisModule.getName();
2971 ClassLoader cl = classLoader;
2972 try {
2973 if (cl == null) {
2974 return BootLoader.findResource(mn, name);
2975 } else {
2976 return cl.findResource(mn, name);
2977 }
2978 } catch (IOException ioe) {
2979 return null;
2980 }
2981 }
2982
2983 // unnamed module
2984 ClassLoader cl = classLoader;
2985 if (cl == null) {
2986 return ClassLoader.getSystemResource(name);
2987 } else {
2988 return cl.getResource(name);
2989 }
2990 }
2991
2992 /**
2993 * Returns true if a resource with the given name can be located by the
2994 * given caller. All resources in a module can be located by code in
2995 * the module. For other callers, then the package needs to be open to
2996 * the caller.
2997 */
2998 private boolean isOpenToCaller(String name, Class<?> caller) {
2999 // assert getModule().isNamed();
3000 Module thisModule = getModule();
3001 Module callerModule = (caller != null) ? caller.getModule() : null;
3002 if (callerModule != thisModule) {
3003 String pn = Resources.toPackageName(name);
3004 if (thisModule.getDescriptor().packages().contains(pn)) {
3005 if (callerModule == null && !thisModule.isOpen(pn)) {
3006 // no caller, package not open
3007 return false;
3008 }
3009 if (!thisModule.isOpen(pn, callerModule)) {
3010 // package not open to caller
3011 return false;
3012 }
3013 }
3014 }
3015 return true;
3016 }
3017
3018
3019 /** protection domain returned when the internal domain is null */
3020 private static java.security.ProtectionDomain allPermDomain;
3021
3022 /**
3023 * Returns the {@code ProtectionDomain} of this class. If there is a
3024 * security manager installed, this method first calls the security
3025 * manager's {@code checkPermission} method with a
3026 * {@code RuntimePermission("getProtectionDomain")} permission to
3027 * ensure it's ok to get the
3028 * {@code ProtectionDomain}.
3029 *
3030 * @return the ProtectionDomain of this class
3031 *
3032 * @throws SecurityException
3033 * if a security manager exists and its
3034 * {@code checkPermission} method doesn't allow
3035 * getting the ProtectionDomain.
3036 *
3037 * @see java.security.ProtectionDomain
3038 * @see SecurityManager#checkPermission
3039 * @see java.lang.RuntimePermission
3040 * @since 1.2
3041 */
3042 public java.security.ProtectionDomain getProtectionDomain() {
3043 @SuppressWarnings("removal")
3044 SecurityManager sm = System.getSecurityManager();
3045 if (sm != null) {
3046 sm.checkPermission(SecurityConstants.GET_PD_PERMISSION);
3047 }
3048 return protectionDomain();
3049 }
3050
3051 // package-private
3052 java.security.ProtectionDomain protectionDomain() {
3053 java.security.ProtectionDomain pd = getProtectionDomain0();
3054 if (pd == null) {
3055 if (allPermDomain == null) {
3056 java.security.Permissions perms =
3057 new java.security.Permissions();
3058 perms.add(SecurityConstants.ALL_PERMISSION);
3059 allPermDomain =
3060 new java.security.ProtectionDomain(null, perms);
3061 }
3062 pd = allPermDomain;
3063 }
3064 return pd;
3065 }
3066
3067 /**
3068 * Returns the ProtectionDomain of this class.
3069 */
3070 private native java.security.ProtectionDomain getProtectionDomain0();
3071
3072 /*
3073 * Return the Virtual Machine's Class object for the named
3074 * primitive type.
3075 */
3076 static native Class<?> getPrimitiveClass(String name);
3077
3078 /*
3079 * Check if client is allowed to access members. If access is denied,
3080 * throw a SecurityException.
3081 *
3082 * This method also enforces package access.
3083 *
3084 * <p> Default policy: allow all clients access with normal Java access
3085 * control.
3086 *
3087 * <p> NOTE: should only be called if a SecurityManager is installed
3088 */
3089 private void checkMemberAccess(@SuppressWarnings("removal") SecurityManager sm, int which,
3090 Class<?> caller, boolean checkProxyInterfaces) {
3091 /* Default policy allows access to all {@link Member#PUBLIC} members,
3092 * as well as access to classes that have the same class loader as the caller.
3093 * In all other cases, it requires RuntimePermission("accessDeclaredMembers")
3094 * permission.
3095 */
3096 final ClassLoader ccl = ClassLoader.getClassLoader(caller);
3097 if (which != Member.PUBLIC) {
3098 final ClassLoader cl = classLoader;
3099 if (ccl != cl) {
3100 sm.checkPermission(SecurityConstants.CHECK_MEMBER_ACCESS_PERMISSION);
3101 }
3102 }
3103 this.checkPackageAccess(sm, ccl, checkProxyInterfaces);
3104 }
3105
3106 /*
3107 * Checks if a client loaded in ClassLoader ccl is allowed to access this
3108 * class under the current package access policy. If access is denied,
3109 * throw a SecurityException.
3110 *
3111 * NOTE: this method should only be called if a SecurityManager is active
3112 */
3113 private void checkPackageAccess(@SuppressWarnings("removal") SecurityManager sm, final ClassLoader ccl,
3114 boolean checkProxyInterfaces) {
3115 final ClassLoader cl = classLoader;
3116
3117 if (ReflectUtil.needsPackageAccessCheck(ccl, cl)) {
3118 String pkg = this.getPackageName();
3119 if (!pkg.isEmpty()) {
3120 // skip the package access check on a proxy class in default proxy package
3121 if (!Proxy.isProxyClass(this) || ReflectUtil.isNonPublicProxyClass(this)) {
3122 sm.checkPackageAccess(pkg);
3123 }
3124 }
3125 }
3126 // check package access on the proxy interfaces
3127 if (checkProxyInterfaces && Proxy.isProxyClass(this)) {
3128 ReflectUtil.checkProxyPackageAccess(ccl, this.getInterfaces());
3129 }
3130 }
3131
3132 /*
3133 * Checks if a client loaded in ClassLoader ccl is allowed to access the provided
3134 * classes under the current package access policy. If access is denied,
3135 * throw a SecurityException.
3136 *
3137 * NOTE: this method should only be called if a SecurityManager is active
3138 * classes must be non-empty
3139 * all classes provided must be loaded by the same ClassLoader
3140 * NOTE: this method does not support Proxy classes
3141 */
3142 private static void checkPackageAccessForPermittedSubclasses(@SuppressWarnings("removal") SecurityManager sm,
3143 final ClassLoader ccl, Class<?>[] subClasses) {
3144 final ClassLoader cl = subClasses[0].classLoader;
3145
3146 if (ReflectUtil.needsPackageAccessCheck(ccl, cl)) {
3147 Set<String> packages = new HashSet<>();
3148
3149 for (Class<?> c : subClasses) {
3150 if (Proxy.isProxyClass(c))
3151 throw new InternalError("a permitted subclass should not be a proxy class: " + c);
3152 String pkg = c.getPackageName();
3153 if (!pkg.isEmpty()) {
3154 packages.add(pkg);
3155 }
3156 }
3157 for (String pkg : packages) {
3158 sm.checkPackageAccess(pkg);
3159 }
3160 }
3161 }
3162
3163 /**
3164 * Add a package name prefix if the name is not absolute. Remove leading "/"
3165 * if name is absolute
3166 */
3167 private String resolveName(String name) {
3168 if (!name.startsWith("/")) {
3169 String baseName = getPackageName();
3170 if (!baseName.isEmpty()) {
3171 int len = baseName.length() + 1 + name.length();
3172 StringBuilder sb = new StringBuilder(len);
3173 name = sb.append(baseName.replace('.', '/'))
3174 .append('/')
3175 .append(name)
3176 .toString();
3177 }
3178 } else {
3179 name = name.substring(1);
3180 }
3181 return name;
3182 }
3183
3184 /**
3185 * Atomic operations support.
3186 */
3187 private static class Atomic {
3188 // initialize Unsafe machinery here, since we need to call Class.class instance method
3189 // and have to avoid calling it in the static initializer of the Class class...
3190 private static final Unsafe unsafe = Unsafe.getUnsafe();
3191 // offset of Class.reflectionData instance field
3192 private static final long reflectionDataOffset
3193 = unsafe.objectFieldOffset(Class.class, "reflectionData");
3194 // offset of Class.annotationType instance field
3195 private static final long annotationTypeOffset
3196 = unsafe.objectFieldOffset(Class.class, "annotationType");
3197 // offset of Class.annotationData instance field
3198 private static final long annotationDataOffset
3199 = unsafe.objectFieldOffset(Class.class, "annotationData");
3200
3201 static <T> boolean casReflectionData(Class<?> clazz,
3202 SoftReference<ReflectionData<T>> oldData,
3203 SoftReference<ReflectionData<T>> newData) {
3204 return unsafe.compareAndSetReference(clazz, reflectionDataOffset, oldData, newData);
3205 }
3206
3207 static boolean casAnnotationType(Class<?> clazz,
3208 AnnotationType oldType,
3209 AnnotationType newType) {
3210 return unsafe.compareAndSetReference(clazz, annotationTypeOffset, oldType, newType);
3211 }
3212
3213 static boolean casAnnotationData(Class<?> clazz,
3214 AnnotationData oldData,
3215 AnnotationData newData) {
3216 return unsafe.compareAndSetReference(clazz, annotationDataOffset, oldData, newData);
3217 }
3218 }
3219
3220 /**
3221 * Reflection support.
3222 */
3223
3224 // Reflection data caches various derived names and reflective members. Cached
3225 // values may be invalidated when JVM TI RedefineClasses() is called
3226 private static class ReflectionData<T> {
3227 volatile Field[] declaredFields;
3228 volatile Field[] publicFields;
3229 volatile Method[] declaredMethods;
3230 volatile Method[] publicMethods;
3231 volatile Constructor<T>[] declaredConstructors;
3232 volatile Constructor<T>[] publicConstructors;
3233 // Intermediate results for getFields and getMethods
3234 volatile Field[] declaredPublicFields;
3235 volatile Method[] declaredPublicMethods;
3236 volatile Class<?>[] interfaces;
3237
3238 // Cached names
3239 String simpleName;
3240 String canonicalName;
3241 static final String NULL_SENTINEL = new String();
3242
3243 // Value of classRedefinedCount when we created this ReflectionData instance
3244 final int redefinedCount;
3245
3246 ReflectionData(int redefinedCount) {
3247 this.redefinedCount = redefinedCount;
3248 }
3249 }
3250
3251 private transient volatile SoftReference<ReflectionData<T>> reflectionData;
3252
3253 // Incremented by the VM on each call to JVM TI RedefineClasses()
3254 // that redefines this class or a superclass.
3255 private transient volatile int classRedefinedCount;
3256
3257 // Lazily create and cache ReflectionData
3258 private ReflectionData<T> reflectionData() {
3259 SoftReference<ReflectionData<T>> reflectionData = this.reflectionData;
3260 int classRedefinedCount = this.classRedefinedCount;
3261 ReflectionData<T> rd;
3262 if (reflectionData != null &&
3263 (rd = reflectionData.get()) != null &&
3264 rd.redefinedCount == classRedefinedCount) {
3265 return rd;
3266 }
3267 // else no SoftReference or cleared SoftReference or stale ReflectionData
3268 // -> create and replace new instance
3269 return newReflectionData(reflectionData, classRedefinedCount);
3270 }
3271
3272 private ReflectionData<T> newReflectionData(SoftReference<ReflectionData<T>> oldReflectionData,
3273 int classRedefinedCount) {
3274 while (true) {
3275 ReflectionData<T> rd = new ReflectionData<>(classRedefinedCount);
3276 // try to CAS it...
3277 if (Atomic.casReflectionData(this, oldReflectionData, new SoftReference<>(rd))) {
3278 return rd;
3279 }
3280 // else retry
3281 oldReflectionData = this.reflectionData;
3282 classRedefinedCount = this.classRedefinedCount;
3283 if (oldReflectionData != null &&
3284 (rd = oldReflectionData.get()) != null &&
3285 rd.redefinedCount == classRedefinedCount) {
3286 return rd;
3287 }
3288 }
3289 }
3290
3291 // Generic signature handling
3292 private native String getGenericSignature0();
3293
3294 // Generic info repository; lazily initialized
3295 private transient volatile ClassRepository genericInfo;
3296
3297 // accessor for factory
3298 private GenericsFactory getFactory() {
3299 // create scope and factory
3300 return CoreReflectionFactory.make(this, ClassScope.make(this));
3301 }
3302
3303 // accessor for generic info repository;
3304 // generic info is lazily initialized
3305 private ClassRepository getGenericInfo() {
3306 ClassRepository genericInfo = this.genericInfo;
3307 if (genericInfo == null) {
3308 String signature = getGenericSignature0();
3309 if (signature == null) {
3310 genericInfo = ClassRepository.NONE;
3311 } else {
3312 genericInfo = ClassRepository.make(signature, getFactory());
3313 }
3314 this.genericInfo = genericInfo;
3315 }
3316 return (genericInfo != ClassRepository.NONE) ? genericInfo : null;
3317 }
3318
3319 // Annotations handling
3320 native byte[] getRawAnnotations();
3321 // Since 1.8
3322 native byte[] getRawTypeAnnotations();
3323 static byte[] getExecutableTypeAnnotationBytes(Executable ex) {
3324 return getReflectionFactory().getExecutableTypeAnnotationBytes(ex);
3325 }
3326
3327 native ConstantPool getConstantPool();
3328
3329 //
3330 //
3331 // java.lang.reflect.Field handling
3332 //
3333 //
3334
3335 // Returns an array of "root" fields. These Field objects must NOT
3336 // be propagated to the outside world, but must instead be copied
3337 // via ReflectionFactory.copyField.
3338 private Field[] privateGetDeclaredFields(boolean publicOnly) {
3339 Field[] res;
3340 ReflectionData<T> rd = reflectionData();
3341 if (rd != null) {
3342 res = publicOnly ? rd.declaredPublicFields : rd.declaredFields;
3343 if (res != null) return res;
3344 }
3345 // No cached value available; request value from VM
3346 res = Reflection.filterFields(this, getDeclaredFields0(publicOnly));
3347 if (rd != null) {
3348 if (publicOnly) {
3349 rd.declaredPublicFields = res;
3350 } else {
3351 rd.declaredFields = res;
3352 }
3353 }
3354 return res;
3355 }
3356
3357 // Returns an array of "root" fields. These Field objects must NOT
3358 // be propagated to the outside world, but must instead be copied
3359 // via ReflectionFactory.copyField.
3360 private Field[] privateGetPublicFields() {
3361 Field[] res;
3362 ReflectionData<T> rd = reflectionData();
3363 if (rd != null) {
3364 res = rd.publicFields;
3365 if (res != null) return res;
3366 }
3367
3368 // Use a linked hash set to ensure order is preserved and
3369 // fields from common super interfaces are not duplicated
3370 LinkedHashSet<Field> fields = new LinkedHashSet<>();
3371
3372 // Local fields
3373 addAll(fields, privateGetDeclaredFields(true));
3374
3375 // Direct superinterfaces, recursively
3376 for (Class<?> si : getInterfaces()) {
3377 addAll(fields, si.privateGetPublicFields());
3378 }
3379
3380 // Direct superclass, recursively
3381 Class<?> sc = getSuperclass();
3382 if (sc != null) {
3383 addAll(fields, sc.privateGetPublicFields());
3384 }
3385
3386 res = fields.toArray(new Field[0]);
3387 if (rd != null) {
3388 rd.publicFields = res;
3389 }
3390 return res;
3391 }
3392
3393 private static void addAll(Collection<Field> c, Field[] o) {
3394 for (Field f : o) {
3395 c.add(f);
3396 }
3397 }
3398
3399
3400 //
3401 //
3402 // java.lang.reflect.Constructor handling
3403 //
3404 //
3405
3406 // Returns an array of "root" constructors. These Constructor
3407 // objects must NOT be propagated to the outside world, but must
3408 // instead be copied via ReflectionFactory.copyConstructor.
3409 private Constructor<T>[] privateGetDeclaredConstructors(boolean publicOnly) {
3410 Constructor<T>[] res;
3411 ReflectionData<T> rd = reflectionData();
3412 if (rd != null) {
3413 res = publicOnly ? rd.publicConstructors : rd.declaredConstructors;
3414 if (res != null) return res;
3415 }
3416 // No cached value available; request value from VM
3417 if (isInterface()) {
3418 @SuppressWarnings("unchecked")
3419 Constructor<T>[] temporaryRes = (Constructor<T>[]) new Constructor<?>[0];
3420 res = temporaryRes;
3421 } else {
3422 res = getDeclaredConstructors0(publicOnly);
3423 }
3424 if (rd != null) {
3425 if (publicOnly) {
3426 rd.publicConstructors = res;
3427 } else {
3428 rd.declaredConstructors = res;
3429 }
3430 }
3431 return res;
3432 }
3433
3434 //
3435 //
3436 // java.lang.reflect.Method handling
3437 //
3438 //
3439
3440 // Returns an array of "root" methods. These Method objects must NOT
3441 // be propagated to the outside world, but must instead be copied
3442 // via ReflectionFactory.copyMethod.
3443 private Method[] privateGetDeclaredMethods(boolean publicOnly) {
3444 Method[] res;
3445 ReflectionData<T> rd = reflectionData();
3446 if (rd != null) {
3447 res = publicOnly ? rd.declaredPublicMethods : rd.declaredMethods;
3448 if (res != null) return res;
3449 }
3450 // No cached value available; request value from VM
3451 res = Reflection.filterMethods(this, getDeclaredMethods0(publicOnly));
3452 if (rd != null) {
3453 if (publicOnly) {
3454 rd.declaredPublicMethods = res;
3455 } else {
3456 rd.declaredMethods = res;
3457 }
3458 }
3459 return res;
3460 }
3461
3462 // Returns an array of "root" methods. These Method objects must NOT
3463 // be propagated to the outside world, but must instead be copied
3464 // via ReflectionFactory.copyMethod.
3465 private Method[] privateGetPublicMethods() {
3466 Method[] res;
3467 ReflectionData<T> rd = reflectionData();
3468 if (rd != null) {
3469 res = rd.publicMethods;
3470 if (res != null) return res;
3471 }
3472
3473 // No cached value available; compute value recursively.
3474 // Start by fetching public declared methods...
3475 PublicMethods pms = new PublicMethods();
3476 for (Method m : privateGetDeclaredMethods(/* publicOnly */ true)) {
3477 pms.merge(m);
3478 }
3479 // ...then recur over superclass methods...
3480 Class<?> sc = getSuperclass();
3481 if (sc != null) {
3482 for (Method m : sc.privateGetPublicMethods()) {
3483 pms.merge(m);
3484 }
3485 }
3486 // ...and finally over direct superinterfaces.
3487 for (Class<?> intf : getInterfaces(/* cloneArray */ false)) {
3488 for (Method m : intf.privateGetPublicMethods()) {
3489 // static interface methods are not inherited
3490 if (!Modifier.isStatic(m.getModifiers())) {
3491 pms.merge(m);
3492 }
3493 }
3494 }
3495
3496 res = pms.toArray();
3497 if (rd != null) {
3498 rd.publicMethods = res;
3499 }
3500 return res;
3501 }
3502
3503
3504 //
3505 // Helpers for fetchers of one field, method, or constructor
3506 //
3507
3508 // This method does not copy the returned Field object!
3509 private static Field searchFields(Field[] fields, String name) {
3510 for (Field field : fields) {
3511 if (field.getName().equals(name)) {
3512 return field;
3513 }
3514 }
3515 return null;
3516 }
3517
3518 // Returns a "root" Field object. This Field object must NOT
3519 // be propagated to the outside world, but must instead be copied
3520 // via ReflectionFactory.copyField.
3521 private Field getField0(String name) {
3522 // Note: the intent is that the search algorithm this routine
3523 // uses be equivalent to the ordering imposed by
3524 // privateGetPublicFields(). It fetches only the declared
3525 // public fields for each class, however, to reduce the number
3526 // of Field objects which have to be created for the common
3527 // case where the field being requested is declared in the
3528 // class which is being queried.
3529 Field res;
3530 // Search declared public fields
3531 if ((res = searchFields(privateGetDeclaredFields(true), name)) != null) {
3532 return res;
3533 }
3534 // Direct superinterfaces, recursively
3535 Class<?>[] interfaces = getInterfaces(/* cloneArray */ false);
3536 for (Class<?> c : interfaces) {
3537 if ((res = c.getField0(name)) != null) {
3538 return res;
3539 }
3540 }
3541 // Direct superclass, recursively
3542 if (!isInterface()) {
3543 Class<?> c = getSuperclass();
3544 if (c != null) {
3545 if ((res = c.getField0(name)) != null) {
3546 return res;
3547 }
3548 }
3549 }
3550 return null;
3551 }
3552
3553 // This method does not copy the returned Method object!
3554 private static Method searchMethods(Method[] methods,
3555 String name,
3556 Class<?>[] parameterTypes)
3557 {
3558 ReflectionFactory fact = getReflectionFactory();
3559 Method res = null;
3560 for (Method m : methods) {
3561 if (m.getName().equals(name)
3562 && arrayContentsEq(parameterTypes,
3563 fact.getExecutableSharedParameterTypes(m))
3564 && (res == null
3565 || (res.getReturnType() != m.getReturnType()
3566 && res.getReturnType().isAssignableFrom(m.getReturnType()))))
3567 res = m;
3568 }
3569 return res;
3570 }
3571
3572 private static final Class<?>[] EMPTY_CLASS_ARRAY = new Class<?>[0];
3573
3574 // Returns a "root" Method object. This Method object must NOT
3575 // be propagated to the outside world, but must instead be copied
3576 // via ReflectionFactory.copyMethod.
3577 private Method getMethod0(String name, Class<?>[] parameterTypes) {
3578 PublicMethods.MethodList res = getMethodsRecursive(
3579 name,
3580 parameterTypes == null ? EMPTY_CLASS_ARRAY : parameterTypes,
3581 /* includeStatic */ true);
3582 return res == null ? null : res.getMostSpecific();
3583 }
3584
3585 // Returns a list of "root" Method objects. These Method objects must NOT
3586 // be propagated to the outside world, but must instead be copied
3587 // via ReflectionFactory.copyMethod.
3588 private PublicMethods.MethodList getMethodsRecursive(String name,
3589 Class<?>[] parameterTypes,
3590 boolean includeStatic) {
3591 // 1st check declared public methods
3592 Method[] methods = privateGetDeclaredMethods(/* publicOnly */ true);
3593 PublicMethods.MethodList res = PublicMethods.MethodList
3594 .filter(methods, name, parameterTypes, includeStatic);
3595 // if there is at least one match among declared methods, we need not
3596 // search any further as such match surely overrides matching methods
3597 // declared in superclass(es) or interface(s).
3598 if (res != null) {
3599 return res;
3600 }
3601
3602 // if there was no match among declared methods,
3603 // we must consult the superclass (if any) recursively...
3604 Class<?> sc = getSuperclass();
3605 if (sc != null) {
3606 res = sc.getMethodsRecursive(name, parameterTypes, includeStatic);
3607 }
3608
3609 // ...and coalesce the superclass methods with methods obtained
3610 // from directly implemented interfaces excluding static methods...
3611 for (Class<?> intf : getInterfaces(/* cloneArray */ false)) {
3612 res = PublicMethods.MethodList.merge(
3613 res, intf.getMethodsRecursive(name, parameterTypes,
3614 /* includeStatic */ false));
3615 }
3616
3617 return res;
3618 }
3619
3620 // Returns a "root" Constructor object. This Constructor object must NOT
3621 // be propagated to the outside world, but must instead be copied
3622 // via ReflectionFactory.copyConstructor.
3623 private Constructor<T> getConstructor0(Class<?>[] parameterTypes,
3624 int which) throws NoSuchMethodException
3625 {
3626 ReflectionFactory fact = getReflectionFactory();
3627 Constructor<T>[] constructors = privateGetDeclaredConstructors((which == Member.PUBLIC));
3628 for (Constructor<T> constructor : constructors) {
3629 if (arrayContentsEq(parameterTypes,
3630 fact.getExecutableSharedParameterTypes(constructor))) {
3631 return constructor;
3632 }
3633 }
3634 throw new NoSuchMethodException(methodToString("<init>", parameterTypes));
3635 }
3636
3637 //
3638 // Other helpers and base implementation
3639 //
3640
3641 private static boolean arrayContentsEq(Object[] a1, Object[] a2) {
3642 if (a1 == null) {
3643 return a2 == null || a2.length == 0;
3644 }
3645
3646 if (a2 == null) {
3647 return a1.length == 0;
3648 }
3649
3650 if (a1.length != a2.length) {
3651 return false;
3652 }
3653
3654 for (int i = 0; i < a1.length; i++) {
3655 if (a1[i] != a2[i]) {
3656 return false;
3657 }
3658 }
3659
3660 return true;
3661 }
3662
3663 private static Field[] copyFields(Field[] arg) {
3664 Field[] out = new Field[arg.length];
3665 ReflectionFactory fact = getReflectionFactory();
3666 for (int i = 0; i < arg.length; i++) {
3667 out[i] = fact.copyField(arg[i]);
3668 }
3669 return out;
3670 }
3671
3672 private static Method[] copyMethods(Method[] arg) {
3673 Method[] out = new Method[arg.length];
3674 ReflectionFactory fact = getReflectionFactory();
3675 for (int i = 0; i < arg.length; i++) {
3676 out[i] = fact.copyMethod(arg[i]);
3677 }
3678 return out;
3679 }
3680
3681 private static <U> Constructor<U>[] copyConstructors(Constructor<U>[] arg) {
3682 Constructor<U>[] out = arg.clone();
3683 ReflectionFactory fact = getReflectionFactory();
3684 for (int i = 0; i < out.length; i++) {
3685 out[i] = fact.copyConstructor(out[i]);
3686 }
3687 return out;
3688 }
3689
3690 private native Field[] getDeclaredFields0(boolean publicOnly);
3691 private native Method[] getDeclaredMethods0(boolean publicOnly);
3692 private native Constructor<T>[] getDeclaredConstructors0(boolean publicOnly);
3693 private native Class<?>[] getDeclaredClasses0();
3694
3695 /*
3696 * Returns an array containing the components of the Record attribute,
3697 * or null if the attribute is not present.
3698 *
3699 * Note that this method returns non-null array on a class with
3700 * the Record attribute even if this class is not a record.
3701 */
3702 private native RecordComponent[] getRecordComponents0();
3703 private native boolean isRecord0();
3704
3705 /**
3706 * Helper method to get the method name from arguments.
3707 */
3708 private String methodToString(String name, Class<?>[] argTypes) {
3709 return getName() + '.' + name +
3710 ((argTypes == null || argTypes.length == 0) ?
3711 "()" :
3712 Arrays.stream(argTypes)
3713 .map(c -> c == null ? "null" : c.getName())
3714 .collect(Collectors.joining(",", "(", ")")));
3715 }
3716
3717 /** use serialVersionUID from JDK 1.1 for interoperability */
3718 @java.io.Serial
3719 private static final long serialVersionUID = 3206093459760846163L;
3720
3721
3722 /**
3723 * Class Class is special cased within the Serialization Stream Protocol.
3724 *
3725 * A Class instance is written initially into an ObjectOutputStream in the
3726 * following format:
3727 * <pre>
3728 * {@code TC_CLASS} ClassDescriptor
3729 * A ClassDescriptor is a special cased serialization of
3730 * a {@code java.io.ObjectStreamClass} instance.
3731 * </pre>
3732 * A new handle is generated for the initial time the class descriptor
3733 * is written into the stream. Future references to the class descriptor
3734 * are written as references to the initial class descriptor instance.
3735 *
3736 * @see java.io.ObjectStreamClass
3737 */
3738 @java.io.Serial
3739 private static final ObjectStreamField[] serialPersistentFields =
3740 new ObjectStreamField[0];
3741
3742
3743 /**
3744 * Returns the assertion status that would be assigned to this
3745 * class if it were to be initialized at the time this method is invoked.
3746 * If this class has had its assertion status set, the most recent
3747 * setting will be returned; otherwise, if any package default assertion
3748 * status pertains to this class, the most recent setting for the most
3749 * specific pertinent package default assertion status is returned;
3750 * otherwise, if this class is not a system class (i.e., it has a
3751 * class loader) its class loader's default assertion status is returned;
3752 * otherwise, the system class default assertion status is returned.
3753 *
3754 * @apiNote
3755 * Few programmers will have any need for this method; it is provided
3756 * for the benefit of the JDK itself. (It allows a class to determine at
3757 * the time that it is initialized whether assertions should be enabled.)
3758 * Note that this method is not guaranteed to return the actual
3759 * assertion status that was (or will be) associated with the specified
3760 * class when it was (or will be) initialized.
3761 *
3762 * @return the desired assertion status of the specified class.
3763 * @see java.lang.ClassLoader#setClassAssertionStatus
3764 * @see java.lang.ClassLoader#setPackageAssertionStatus
3765 * @see java.lang.ClassLoader#setDefaultAssertionStatus
3766 * @since 1.4
3767 */
3768 public boolean desiredAssertionStatus() {
3769 ClassLoader loader = classLoader;
3770 // If the loader is null this is a system class, so ask the VM
3771 if (loader == null)
3772 return desiredAssertionStatus0(this);
3773
3774 // If the classloader has been initialized with the assertion
3775 // directives, ask it. Otherwise, ask the VM.
3776 synchronized(loader.assertionLock) {
3777 if (loader.classAssertionStatus != null) {
3778 return loader.desiredAssertionStatus(getName());
3779 }
3780 }
3781 return desiredAssertionStatus0(this);
3782 }
3783
3784 // Retrieves the desired assertion status of this class from the VM
3785 private static native boolean desiredAssertionStatus0(Class<?> clazz);
3786
3787 /**
3788 * Returns true if and only if this class was declared as an enum in the
3789 * source code.
3790 *
3791 * Note that {@link java.lang.Enum} is not itself an enum class.
3792 *
3793 * Also note that if an enum constant is declared with a class body,
3794 * the class of that enum constant object is an anonymous class
3795 * and <em>not</em> the class of the declaring enum class. The
3796 * {@link Enum#getDeclaringClass} method of an enum constant can
3797 * be used to get the class of the enum class declaring the
3798 * constant.
3799 *
3800 * @return true if and only if this class was declared as an enum in the
3801 * source code
3802 * @since 1.5
3803 * @jls 8.9.1 Enum Constants
3804 */
3805 public boolean isEnum() {
3806 // An enum must both directly extend java.lang.Enum and have
3807 // the ENUM bit set; classes for specialized enum constants
3808 // don't do the former.
3809 return (this.getModifiers() & ENUM) != 0 &&
3810 this.getSuperclass() == java.lang.Enum.class;
3811 }
3812
3813 /**
3814 * Returns {@code true} if and only if this class is a record class.
3815 *
3816 * <p> The {@linkplain #getSuperclass() direct superclass} of a record
3817 * class is {@code java.lang.Record}. A record class is {@linkplain
3818 * Modifier#FINAL final}. A record class has (possibly zero) record
3819 * components; {@link #getRecordComponents()} returns a non-null but
3820 * possibly empty value for a record.
3821 *
3822 * <p> Note that class {@link Record} is not a record class and thus
3823 * invoking this method on class {@code Record} returns {@code false}.
3824 *
3825 * @return true if and only if this class is a record class, otherwise false
3826 * @jls 8.10 Record Classes
3827 * @since 16
3828 */
3829 public boolean isRecord() {
3830 // this superclass and final modifier check is not strictly necessary
3831 // they are intrinsified and serve as a fast-path check
3832 return getSuperclass() == java.lang.Record.class &&
3833 (this.getModifiers() & Modifier.FINAL) != 0 &&
3834 isRecord0();
3835 }
3836
3837 // Fetches the factory for reflective objects
3838 @SuppressWarnings("removal")
3839 private static ReflectionFactory getReflectionFactory() {
3840 var factory = reflectionFactory;
3841 if (factory != null) {
3842 return factory;
3843 }
3844 return reflectionFactory =
3845 java.security.AccessController.doPrivileged
3846 (new ReflectionFactory.GetReflectionFactoryAction());
3847 }
3848 private static ReflectionFactory reflectionFactory;
3849
3850 /**
3851 * Returns the elements of this enum class or null if this
3852 * Class object does not represent an enum class.
3853 *
3854 * @return an array containing the values comprising the enum class
3855 * represented by this {@code Class} object in the order they're
3856 * declared, or null if this {@code Class} object does not
3857 * represent an enum class
3858 * @since 1.5
3859 * @jls 8.9.1 Enum Constants
3860 */
3861 public T[] getEnumConstants() {
3862 T[] values = getEnumConstantsShared();
3863 return (values != null) ? values.clone() : null;
3864 }
3865
3866 /**
3867 * Returns the elements of this enum class or null if this
3868 * Class object does not represent an enum class;
3869 * identical to getEnumConstants except that the result is
3870 * uncloned, cached, and shared by all callers.
3871 */
3872 @SuppressWarnings("removal")
3873 T[] getEnumConstantsShared() {
3874 T[] constants = enumConstants;
3875 if (constants == null) {
3876 if (!isEnum()) return null;
3877 try {
3878 final Method values = getMethod("values");
3879 java.security.AccessController.doPrivileged(
3880 new java.security.PrivilegedAction<>() {
3881 public Void run() {
3882 values.setAccessible(true);
3883 return null;
3884 }
3885 });
3886 @SuppressWarnings("unchecked")
3887 T[] temporaryConstants = (T[])values.invoke(null);
3888 enumConstants = constants = temporaryConstants;
3889 }
3890 // These can happen when users concoct enum-like classes
3891 // that don't comply with the enum spec.
3892 catch (InvocationTargetException | NoSuchMethodException |
3893 IllegalAccessException ex) { return null; }
3894 }
3895 return constants;
3896 }
3897 private transient volatile T[] enumConstants;
3898
3899 /**
3900 * Returns a map from simple name to enum constant. This package-private
3901 * method is used internally by Enum to implement
3902 * {@code public static <T extends Enum<T>> T valueOf(Class<T>, String)}
3903 * efficiently. Note that the map is returned by this method is
3904 * created lazily on first use. Typically it won't ever get created.
3905 */
3906 Map<String, T> enumConstantDirectory() {
3907 Map<String, T> directory = enumConstantDirectory;
3908 if (directory == null) {
3909 T[] universe = getEnumConstantsShared();
3910 if (universe == null)
3911 throw new IllegalArgumentException(
3912 getName() + " is not an enum class");
3913 directory = new HashMap<>((int)(universe.length / 0.75f) + 1);
3914 for (T constant : universe) {
3915 directory.put(((Enum<?>)constant).name(), constant);
3916 }
3917 enumConstantDirectory = directory;
3918 }
3919 return directory;
3920 }
3921 private transient volatile Map<String, T> enumConstantDirectory;
3922
3923 /**
3924 * Casts an object to the class or interface represented
3925 * by this {@code Class} object.
3926 *
3927 * @param obj the object to be cast
3928 * @return the object after casting, or null if obj is null
3929 *
3930 * @throws ClassCastException if the object is not
3931 * null and is not assignable to the type T.
3932 *
3933 * @since 1.5
3934 */
3935 @SuppressWarnings("unchecked")
3936 @IntrinsicCandidate
3937 public T cast(Object obj) {
3938 if (obj != null && !isInstance(obj))
3939 throw new ClassCastException(cannotCastMsg(obj));
3940 return (T) obj;
3941 }
3942
3943 private String cannotCastMsg(Object obj) {
3944 return "Cannot cast " + obj.getClass().getName() + " to " + getName();
3945 }
3946
3947 /**
3948 * Casts this {@code Class} object to represent a subclass of the class
3949 * represented by the specified class object. Checks that the cast
3950 * is valid, and throws a {@code ClassCastException} if it is not. If
3951 * this method succeeds, it always returns a reference to this {@code Class} object.
3952 *
3953 * <p>This method is useful when a client needs to "narrow" the type of
3954 * a {@code Class} object to pass it to an API that restricts the
3955 * {@code Class} objects that it is willing to accept. A cast would
3956 * generate a compile-time warning, as the correctness of the cast
3957 * could not be checked at runtime (because generic types are implemented
3958 * by erasure).
3959 *
3960 * @param <U> the type to cast this {@code Class} object to
3961 * @param clazz the class of the type to cast this {@code Class} object to
3962 * @return this {@code Class} object, cast to represent a subclass of
3963 * the specified class object.
3964 * @throws ClassCastException if this {@code Class} object does not
3965 * represent a subclass of the specified class (here "subclass" includes
3966 * the class itself).
3967 * @since 1.5
3968 */
3969 @SuppressWarnings("unchecked")
3970 public <U> Class<? extends U> asSubclass(Class<U> clazz) {
3971 if (clazz.isAssignableFrom(this))
3972 return (Class<? extends U>) this;
3973 else
3974 throw new ClassCastException(this.toString());
3975 }
3976
3977 /**
3978 * {@inheritDoc}
3979 * <p>Note that any annotation returned by this method is a
3980 * declaration annotation.
3981 *
3982 * @throws NullPointerException {@inheritDoc}
3983 * @since 1.5
3984 */
3985 @Override
3986 @SuppressWarnings("unchecked")
3987 public <A extends Annotation> A getAnnotation(Class<A> annotationClass) {
3988 Objects.requireNonNull(annotationClass);
3989
3990 return (A) annotationData().annotations.get(annotationClass);
3991 }
3992
3993 /**
3994 * {@inheritDoc}
3995 * @throws NullPointerException {@inheritDoc}
3996 * @since 1.5
3997 */
3998 @Override
3999 public boolean isAnnotationPresent(Class<? extends Annotation> annotationClass) {
4000 return GenericDeclaration.super.isAnnotationPresent(annotationClass);
4001 }
4002
4003 /**
4004 * {@inheritDoc}
4005 * <p>Note that any annotations returned by this method are
4006 * declaration annotations.
4007 *
4008 * @throws NullPointerException {@inheritDoc}
4009 * @since 1.8
4010 */
4011 @Override
4012 public <A extends Annotation> A[] getAnnotationsByType(Class<A> annotationClass) {
4013 Objects.requireNonNull(annotationClass);
4014
4015 AnnotationData annotationData = annotationData();
4016 return AnnotationSupport.getAssociatedAnnotations(annotationData.declaredAnnotations,
4017 this,
4018 annotationClass);
4019 }
4020
4021 /**
4022 * {@inheritDoc}
4023 * <p>Note that any annotations returned by this method are
4024 * declaration annotations.
4025 *
4026 * @since 1.5
4027 */
4028 @Override
4029 public Annotation[] getAnnotations() {
4030 return AnnotationParser.toArray(annotationData().annotations);
4031 }
4032
4033 /**
4034 * {@inheritDoc}
4035 * <p>Note that any annotation returned by this method is a
4036 * declaration annotation.
4037 *
4038 * @throws NullPointerException {@inheritDoc}
4039 * @since 1.8
4040 */
4041 @Override
4042 @SuppressWarnings("unchecked")
4043 public <A extends Annotation> A getDeclaredAnnotation(Class<A> annotationClass) {
4044 Objects.requireNonNull(annotationClass);
4045
4046 return (A) annotationData().declaredAnnotations.get(annotationClass);
4047 }
4048
4049 /**
4050 * {@inheritDoc}
4051 * <p>Note that any annotations returned by this method are
4052 * declaration annotations.
4053 *
4054 * @throws NullPointerException {@inheritDoc}
4055 * @since 1.8
4056 */
4057 @Override
4058 public <A extends Annotation> A[] getDeclaredAnnotationsByType(Class<A> annotationClass) {
4059 Objects.requireNonNull(annotationClass);
4060
4061 return AnnotationSupport.getDirectlyAndIndirectlyPresent(annotationData().declaredAnnotations,
4062 annotationClass);
4063 }
4064
4065 /**
4066 * {@inheritDoc}
4067 * <p>Note that any annotations returned by this method are
4068 * declaration annotations.
4069 *
4070 * @since 1.5
4071 */
4072 @Override
4073 public Annotation[] getDeclaredAnnotations() {
4074 return AnnotationParser.toArray(annotationData().declaredAnnotations);
4075 }
4076
4077 // annotation data that might get invalidated when JVM TI RedefineClasses() is called
4078 private static class AnnotationData {
4079 final Map<Class<? extends Annotation>, Annotation> annotations;
4080 final Map<Class<? extends Annotation>, Annotation> declaredAnnotations;
4081
4082 // Value of classRedefinedCount when we created this AnnotationData instance
4083 final int redefinedCount;
4084
4085 AnnotationData(Map<Class<? extends Annotation>, Annotation> annotations,
4086 Map<Class<? extends Annotation>, Annotation> declaredAnnotations,
4087 int redefinedCount) {
4088 this.annotations = annotations;
4089 this.declaredAnnotations = declaredAnnotations;
4090 this.redefinedCount = redefinedCount;
4091 }
4092 }
4093
4094 // Annotations cache
4095 @SuppressWarnings("UnusedDeclaration")
4096 private transient volatile AnnotationData annotationData;
4097
4098 private AnnotationData annotationData() {
4099 while (true) { // retry loop
4100 AnnotationData annotationData = this.annotationData;
4101 int classRedefinedCount = this.classRedefinedCount;
4102 if (annotationData != null &&
4103 annotationData.redefinedCount == classRedefinedCount) {
4104 return annotationData;
4105 }
4106 // null or stale annotationData -> optimistically create new instance
4107 AnnotationData newAnnotationData = createAnnotationData(classRedefinedCount);
4108 // try to install it
4109 if (Atomic.casAnnotationData(this, annotationData, newAnnotationData)) {
4110 // successfully installed new AnnotationData
4111 return newAnnotationData;
4112 }
4113 }
4114 }
4115
4116 private AnnotationData createAnnotationData(int classRedefinedCount) {
4117 Map<Class<? extends Annotation>, Annotation> declaredAnnotations =
4118 AnnotationParser.parseAnnotations(getRawAnnotations(), getConstantPool(), this);
4119 Class<?> superClass = getSuperclass();
4120 Map<Class<? extends Annotation>, Annotation> annotations = null;
4121 if (superClass != null) {
4122 Map<Class<? extends Annotation>, Annotation> superAnnotations =
4123 superClass.annotationData().annotations;
4124 for (Map.Entry<Class<? extends Annotation>, Annotation> e : superAnnotations.entrySet()) {
4125 Class<? extends Annotation> annotationClass = e.getKey();
4126 if (AnnotationType.getInstance(annotationClass).isInherited()) {
4127 if (annotations == null) { // lazy construction
4128 annotations = new LinkedHashMap<>((Math.max(
4129 declaredAnnotations.size(),
4130 Math.min(12, declaredAnnotations.size() + superAnnotations.size())
4131 ) * 4 + 2) / 3
4132 );
4133 }
4134 annotations.put(annotationClass, e.getValue());
4135 }
4136 }
4137 }
4138 if (annotations == null) {
4139 // no inherited annotations -> share the Map with declaredAnnotations
4140 annotations = declaredAnnotations;
4141 } else {
4142 // at least one inherited annotation -> declared may override inherited
4143 annotations.putAll(declaredAnnotations);
4144 }
4145 return new AnnotationData(annotations, declaredAnnotations, classRedefinedCount);
4146 }
4147
4148 // Annotation interfaces cache their internal (AnnotationType) form
4149
4150 @SuppressWarnings("UnusedDeclaration")
4151 private transient volatile AnnotationType annotationType;
4152
4153 boolean casAnnotationType(AnnotationType oldType, AnnotationType newType) {
4154 return Atomic.casAnnotationType(this, oldType, newType);
4155 }
4156
4157 AnnotationType getAnnotationType() {
4158 return annotationType;
4159 }
4160
4161 Map<Class<? extends Annotation>, Annotation> getDeclaredAnnotationMap() {
4162 return annotationData().declaredAnnotations;
4163 }
4164
4165 /* Backing store of user-defined values pertaining to this class.
4166 * Maintained by the ClassValue class.
4167 */
4168 transient ClassValue.ClassValueMap classValueMap;
4169
4170 /**
4171 * Returns an {@code AnnotatedType} object that represents the use of a
4172 * type to specify the superclass of the entity represented by this {@code
4173 * Class} object. (The <em>use</em> of type Foo to specify the superclass
4174 * in '... extends Foo' is distinct from the <em>declaration</em> of class
4175 * Foo.)
4176 *
4177 * <p> If this {@code Class} object represents a class whose declaration
4178 * does not explicitly indicate an annotated superclass, then the return
4179 * value is an {@code AnnotatedType} object representing an element with no
4180 * annotations.
4181 *
4182 * <p> If this {@code Class} represents either the {@code Object} class, an
4183 * interface type, an array type, a primitive type, or void, the return
4184 * value is {@code null}.
4185 *
4186 * @return an object representing the superclass
4187 * @since 1.8
4188 */
4189 public AnnotatedType getAnnotatedSuperclass() {
4190 if (this == Object.class ||
4191 isInterface() ||
4192 isArray() ||
4193 isPrimitive() ||
4194 this == Void.TYPE) {
4195 return null;
4196 }
4197
4198 return TypeAnnotationParser.buildAnnotatedSuperclass(getRawTypeAnnotations(), getConstantPool(), this);
4199 }
4200
4201 /**
4202 * Returns an array of {@code AnnotatedType} objects that represent the use
4203 * of types to specify superinterfaces of the entity represented by this
4204 * {@code Class} object. (The <em>use</em> of type Foo to specify a
4205 * superinterface in '... implements Foo' is distinct from the
4206 * <em>declaration</em> of interface Foo.)
4207 *
4208 * <p> If this {@code Class} object represents a class, the return value is
4209 * an array containing objects representing the uses of interface types to
4210 * specify interfaces implemented by the class. The order of the objects in
4211 * the array corresponds to the order of the interface types used in the
4212 * 'implements' clause of the declaration of this {@code Class} object.
4213 *
4214 * <p> If this {@code Class} object represents an interface, the return
4215 * value is an array containing objects representing the uses of interface
4216 * types to specify interfaces directly extended by the interface. The
4217 * order of the objects in the array corresponds to the order of the
4218 * interface types used in the 'extends' clause of the declaration of this
4219 * {@code Class} object.
4220 *
4221 * <p> If this {@code Class} object represents a class or interface whose
4222 * declaration does not explicitly indicate any annotated superinterfaces,
4223 * the return value is an array of length 0.
4224 *
4225 * <p> If this {@code Class} object represents either the {@code Object}
4226 * class, an array type, a primitive type, or void, the return value is an
4227 * array of length 0.
4228 *
4229 * @return an array representing the superinterfaces
4230 * @since 1.8
4231 */
4232 public AnnotatedType[] getAnnotatedInterfaces() {
4233 return TypeAnnotationParser.buildAnnotatedInterfaces(getRawTypeAnnotations(), getConstantPool(), this);
4234 }
4235
4236 private native Class<?> getNestHost0();
4237
4238 /**
4239 * Returns the nest host of the <a href=#nest>nest</a> to which the class
4240 * or interface represented by this {@code Class} object belongs.
4241 * Every class and interface belongs to exactly one nest.
4242 *
4243 * If the nest host of this class or interface has previously
4244 * been determined, then this method returns the nest host.
4245 * If the nest host of this class or interface has
4246 * not previously been determined, then this method determines the nest
4247 * host using the algorithm of JVMS 5.4.4, and returns it.
4248 *
4249 * Often, a class or interface belongs to a nest consisting only of itself,
4250 * in which case this method returns {@code this} to indicate that the class
4251 * or interface is the nest host.
4252 *
4253 * <p>If this {@code Class} object represents a primitive type, an array type,
4254 * or {@code void}, then this method returns {@code this},
4255 * indicating that the represented entity belongs to the nest consisting only of
4256 * itself, and is the nest host.
4257 *
4258 * @return the nest host of this class or interface
4259 *
4260 * @throws SecurityException
4261 * If the returned class is not the current class, and
4262 * if a security manager, <i>s</i>, is present and the caller's
4263 * class loader is not the same as or an ancestor of the class
4264 * loader for the returned class and invocation of {@link
4265 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
4266 * denies access to the package of the returned class
4267 * @since 11
4268 * @jvms 4.7.28 The {@code NestHost} Attribute
4269 * @jvms 4.7.29 The {@code NestMembers} Attribute
4270 * @jvms 5.4.4 Access Control
4271 */
4272 @CallerSensitive
4273 public Class<?> getNestHost() {
4274 if (isPrimitive() || isArray()) {
4275 return this;
4276 }
4277
4278 Class<?> host = getNestHost0();
4279 if (host == this) {
4280 return this;
4281 }
4282 // returning a different class requires a security check
4283 @SuppressWarnings("removal")
4284 SecurityManager sm = System.getSecurityManager();
4285 if (sm != null) {
4286 checkPackageAccess(sm,
4287 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
4288 }
4289 return host;
4290 }
4291
4292 /**
4293 * Determines if the given {@code Class} is a nestmate of the
4294 * class or interface represented by this {@code Class} object.
4295 * Two classes or interfaces are nestmates
4296 * if they have the same {@linkplain #getNestHost() nest host}.
4297 *
4298 * @param c the class to check
4299 * @return {@code true} if this class and {@code c} are members of
4300 * the same nest; and {@code false} otherwise.
4301 *
4302 * @since 11
4303 */
4304 public boolean isNestmateOf(Class<?> c) {
4305 if (this == c) {
4306 return true;
4307 }
4308 if (isPrimitive() || isArray() ||
4309 c.isPrimitive() || c.isArray()) {
4310 return false;
4311 }
4312
4313 return getNestHost() == c.getNestHost();
4314 }
4315
4316 private native Class<?>[] getNestMembers0();
4317
4318 /**
4319 * Returns an array containing {@code Class} objects representing all the
4320 * classes and interfaces that are members of the nest to which the class
4321 * or interface represented by this {@code Class} object belongs.
4322 *
4323 * First, this method obtains the {@linkplain #getNestHost() nest host},
4324 * {@code H}, of the nest to which the class or interface represented by
4325 * this {@code Class} object belongs. The zeroth element of the returned
4326 * array is {@code H}.
4327 *
4328 * Then, for each class or interface {@code C} which is recorded by {@code H}
4329 * as being a member of its nest, this method attempts to obtain the {@code Class}
4330 * object for {@code C} (using {@linkplain #getClassLoader() the defining class
4331 * loader} of the current {@code Class} object), and then obtains the
4332 * {@linkplain #getNestHost() nest host} of the nest to which {@code C} belongs.
4333 * The classes and interfaces which are recorded by {@code H} as being members
4334 * of its nest, and for which {@code H} can be determined as their nest host,
4335 * are indicated by subsequent elements of the returned array. The order of
4336 * such elements is unspecified. Duplicates are permitted.
4337 *
4338 * <p>If this {@code Class} object represents a primitive type, an array type,
4339 * or {@code void}, then this method returns a single-element array containing
4340 * {@code this}.
4341 *
4342 * @apiNote
4343 * The returned array includes only the nest members recorded in the {@code NestMembers}
4344 * attribute, and not any hidden classes that were added to the nest via
4345 * {@link MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
4346 * Lookup::defineHiddenClass}.
4347 *
4348 * @return an array of all classes and interfaces in the same nest as
4349 * this class or interface
4350 *
4351 * @throws SecurityException
4352 * If any returned class is not the current class, and
4353 * if a security manager, <i>s</i>, is present and the caller's
4354 * class loader is not the same as or an ancestor of the class
4355 * loader for that returned class and invocation of {@link
4356 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
4357 * denies access to the package of that returned class
4358 *
4359 * @since 11
4360 * @see #getNestHost()
4361 * @jvms 4.7.28 The {@code NestHost} Attribute
4362 * @jvms 4.7.29 The {@code NestMembers} Attribute
4363 */
4364 @CallerSensitive
4365 public Class<?>[] getNestMembers() {
4366 if (isPrimitive() || isArray()) {
4367 return new Class<?>[] { this };
4368 }
4369 Class<?>[] members = getNestMembers0();
4370 // Can't actually enable this due to bootstrapping issues
4371 // assert(members.length != 1 || members[0] == this); // expected invariant from VM
4372
4373 if (members.length > 1) {
4374 // If we return anything other than the current class we need
4375 // a security check
4376 @SuppressWarnings("removal")
4377 SecurityManager sm = System.getSecurityManager();
4378 if (sm != null) {
4379 checkPackageAccess(sm,
4380 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
4381 }
4382 }
4383 return members;
4384 }
4385
4386 /**
4387 * Returns the descriptor string of the entity (class, interface, array class,
4388 * primitive type, or {@code void}) represented by this {@code Class} object.
4389 *
4390 * <p> If this {@code Class} object represents a class or interface,
4391 * not an array class, then:
4392 * <ul>
4393 * <li> If the class or interface is not {@linkplain Class#isHidden() hidden},
4394 * then the result is a field descriptor (JVMS {@jvms 4.3.2})
4395 * for the class or interface. Calling
4396 * {@link ClassDesc#ofDescriptor(String) ClassDesc::ofDescriptor}
4397 * with the result descriptor string produces a {@link ClassDesc ClassDesc}
4398 * describing this class or interface.
4399 * <li> If the class or interface is {@linkplain Class#isHidden() hidden},
4400 * then the result is a string of the form:
4401 * <blockquote>
4402 * {@code "L" +} <em>N</em> {@code + "." + <suffix> + ";"}
4403 * </blockquote>
4404 * where <em>N</em> is the <a href="ClassLoader.html#binary-name">binary name</a>
4405 * encoded in internal form indicated by the {@code class} file passed to
4406 * {@link MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
4407 * Lookup::defineHiddenClass}, and {@code <suffix>} is an unqualified name.
4408 * A hidden class or interface has no {@linkplain ClassDesc nominal descriptor}.
4409 * The result string is not a type descriptor.
4410 * </ul>
4411 *
4412 * <p> If this {@code Class} object represents an array class, then
4413 * the result is a string consisting of one or more '{@code [}' characters
4414 * representing the depth of the array nesting, followed by the
4415 * descriptor string of the element type.
4416 * <ul>
4417 * <li> If the element type is not a {@linkplain Class#isHidden() hidden} class
4418 * or interface, then this array class can be described nominally.
4419 * Calling {@link ClassDesc#ofDescriptor(String) ClassDesc::ofDescriptor}
4420 * with the result descriptor string produces a {@link ClassDesc ClassDesc}
4421 * describing this array class.
4422 * <li> If the element type is a {@linkplain Class#isHidden() hidden} class or
4423 * interface, then this array class cannot be described nominally.
4424 * The result string is not a type descriptor.
4425 * </ul>
4426 *
4427 * <p> If this {@code Class} object represents a primitive type or
4428 * {@code void}, then the result is a field descriptor string which
4429 * is a one-letter code corresponding to a primitive type or {@code void}
4430 * ({@code "B", "C", "D", "F", "I", "J", "S", "Z", "V"}) (JVMS {@jvms 4.3.2}).
4431 *
4432 * @apiNote
4433 * This is not a strict inverse of {@link #forName};
4434 * distinct classes which share a common name but have different class loaders
4435 * will have identical descriptor strings.
4436 *
4437 * @return the descriptor string for this {@code Class} object
4438 * @jvms 4.3.2 Field Descriptors
4439 * @since 12
4440 */
4441 @Override
4442 public String descriptorString() {
4443 if (isPrimitive())
4444 return Wrapper.forPrimitiveType(this).basicTypeString();
4445
4446 if (isArray()) {
4447 return "[" + componentType.descriptorString();
4448 } else if (isHidden()) {
4449 String name = getName();
4450 int index = name.indexOf('/');
4451 return new StringBuilder(name.length() + 2)
4452 .append('L')
4453 .append(name.substring(0, index).replace('.', '/'))
4454 .append('.')
4455 .append(name, index + 1, name.length())
4456 .append(';')
4457 .toString();
4458 } else {
4459 String name = getName().replace('.', '/');
4460 return new StringBuilder(name.length() + 2)
4461 .append('L')
4462 .append(name)
4463 .append(';')
4464 .toString();
4465 }
4466 }
4467
4468 /**
4469 * Returns the component type of this {@code Class}, if it describes
4470 * an array type, or {@code null} otherwise.
4471 *
4472 * @implSpec
4473 * Equivalent to {@link Class#getComponentType()}.
4474 *
4475 * @return a {@code Class} describing the component type, or {@code null}
4476 * if this {@code Class} does not describe an array type
4477 * @since 12
4478 */
4479 @Override
4480 public Class<?> componentType() {
4481 return isArray() ? componentType : null;
4482 }
4483
4484 /**
4485 * Returns a {@code Class} for an array type whose component type
4486 * is described by this {@linkplain Class}.
4487 *
4488 * @throws UnsupportedOperationException if this component type is {@linkplain
4489 * Void#TYPE void} or if the number of dimensions of the resulting array
4490 * type would exceed 255.
4491 * @return a {@code Class} describing the array type
4492 * @jvms 4.3.2 Field Descriptors
4493 * @jvms 4.4.1 The {@code CONSTANT_Class_info} Structure
4494 * @since 12
4495 */
4496 @Override
4497 public Class<?> arrayType() {
4498 try {
4499 return Array.newInstance(this, 0).getClass();
4500 } catch (IllegalArgumentException iae) {
4501 throw new UnsupportedOperationException(iae);
4502 }
4503 }
4504
4505 /**
4506 * Returns a nominal descriptor for this instance, if one can be
4507 * constructed, or an empty {@link Optional} if one cannot be.
4508 *
4509 * @return An {@link Optional} containing the resulting nominal descriptor,
4510 * or an empty {@link Optional} if one cannot be constructed.
4511 * @since 12
4512 */
4513 @Override
4514 public Optional<ClassDesc> describeConstable() {
4515 Class<?> c = isArray() ? elementType() : this;
4516 return c.isHidden() ? Optional.empty()
4517 : Optional.of(ClassDesc.ofDescriptor(descriptorString()));
4518 }
4519
4520 /**
4521 * Returns {@code true} if and only if the underlying class is a hidden class.
4522 *
4523 * @return {@code true} if and only if this class is a hidden class.
4524 *
4525 * @since 15
4526 * @see MethodHandles.Lookup#defineHiddenClass
4527 */
4528 @IntrinsicCandidate
4529 public native boolean isHidden();
4530
4531 /**
4532 * Returns an array containing {@code Class} objects representing the
4533 * direct subinterfaces or subclasses permitted to extend or
4534 * implement this class or interface if it is sealed. The order of such elements
4535 * is unspecified. The array is empty if this sealed class or interface has no
4536 * permitted subclass. If this {@code Class} object represents a primitive type,
4537 * {@code void}, an array type, or a class or interface that is not sealed,
4538 * that is {@link #isSealed()} returns {@code false}, then this method returns {@code null}.
4539 * Conversely, if {@link #isSealed()} returns {@code true}, then this method
4540 * returns a non-null value.
4541 *
4542 * For each class or interface {@code C} which is recorded as a permitted
4543 * direct subinterface or subclass of this class or interface,
4544 * this method attempts to obtain the {@code Class}
4545 * object for {@code C} (using {@linkplain #getClassLoader() the defining class
4546 * loader} of the current {@code Class} object).
4547 * The {@code Class} objects which can be obtained and which are direct
4548 * subinterfaces or subclasses of this class or interface,
4549 * are indicated by elements of the returned array. If a {@code Class} object
4550 * cannot be obtained, it is silently ignored, and not included in the result
4551 * array.
4552 *
4553 * @return an array of {@code Class} objects of the permitted subclasses of this class or interface,
4554 * or {@code null} if this class or interface is not sealed.
4555 *
4556 * @throws SecurityException
4557 * If a security manager, <i>s</i>, is present and the caller's
4558 * class loader is not the same as or an ancestor of the class
4559 * loader for that returned class and invocation of {@link
4560 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
4561 * denies access to the package of any class in the returned array.
4562 *
4563 * @jls 8.1 Class Declarations
4564 * @jls 9.1 Interface Declarations
4565 * @since 17
4566 */
4567 @CallerSensitive
4568 public Class<?>[] getPermittedSubclasses() {
4569 Class<?>[] subClasses;
4570 if (isArray() || isPrimitive() || (subClasses = getPermittedSubclasses0()) == null) {
4571 return null;
4572 }
4573 if (subClasses.length > 0) {
4574 if (Arrays.stream(subClasses).anyMatch(c -> !isDirectSubType(c))) {
4575 subClasses = Arrays.stream(subClasses)
4576 .filter(this::isDirectSubType)
4577 .toArray(s -> new Class<?>[s]);
4578 }
4579 }
4580 if (subClasses.length > 0) {
4581 // If we return some classes we need a security check:
4582 @SuppressWarnings("removal")
4583 SecurityManager sm = System.getSecurityManager();
4584 if (sm != null) {
4585 checkPackageAccessForPermittedSubclasses(sm,
4586 ClassLoader.getClassLoader(Reflection.getCallerClass()),
4587 subClasses);
4588 }
4589 }
4590 return subClasses;
4591 }
4592
4593 private boolean isDirectSubType(Class<?> c) {
4594 if (isInterface()) {
4595 for (Class<?> i : c.getInterfaces(/* cloneArray */ false)) {
4596 if (i == this) {
4597 return true;
4598 }
4599 }
4600 } else {
4601 return c.getSuperclass() == this;
4602 }
4603 return false;
4604 }
4605
4606 /**
4607 * Returns {@code true} if and only if this {@code Class} object represents
4608 * a sealed class or interface. If this {@code Class} object represents a
4609 * primitive type, {@code void}, or an array type, this method returns
4610 * {@code false}. A sealed class or interface has (possibly zero) permitted
4611 * subclasses; {@link #getPermittedSubclasses()} returns a non-null but
4612 * possibly empty value for a sealed class or interface.
4613 *
4614 * @return {@code true} if and only if this {@code Class} object represents
4615 * a sealed class or interface.
4616 *
4617 * @jls 8.1 Class Declarations
4618 * @jls 9.1 Interface Declarations
4619 * @since 17
4620 */
4621 public boolean isSealed() {
4622 if (isArray() || isPrimitive()) {
4623 return false;
4624 }
4625 return getPermittedSubclasses() != null;
4626 }
4627
4628 private native Class<?>[] getPermittedSubclasses0();
4629 }