1 /*
2 * Copyright (c) 1994, 2018, 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.module.ModuleReader;
30 import java.lang.ref.SoftReference;
31 import java.io.IOException;
32 import java.io.InputStream;
33 import java.io.ObjectStreamField;
34 import java.lang.reflect.AnnotatedElement;
35 import java.lang.reflect.AnnotatedType;
36 import java.lang.reflect.Array;
37 import java.lang.reflect.Constructor;
38 import java.lang.reflect.Executable;
39 import java.lang.reflect.Field;
40 import java.lang.reflect.GenericArrayType;
41 import java.lang.reflect.GenericDeclaration;
42 import java.lang.reflect.InvocationTargetException;
43 import java.lang.reflect.Member;
44 import java.lang.reflect.Method;
45 import java.lang.reflect.Modifier;
46 import java.lang.reflect.Proxy;
47 import java.lang.reflect.Type;
48 import java.lang.reflect.TypeVariable;
49 import java.net.URL;
50 import java.security.AccessController;
51 import java.security.PrivilegedAction;
52 import java.util.ArrayList;
53 import java.util.Arrays;
54 import java.util.Collection;
55 import java.util.HashMap;
56 import java.util.LinkedHashMap;
57 import java.util.LinkedHashSet;
58 import java.util.List;
59 import java.util.Map;
60 import java.util.Objects;
61 import java.util.Set;
62 import java.util.StringJoiner;
63
64 import jdk.internal.HotSpotIntrinsicCandidate;
65 import jdk.internal.loader.BootLoader;
66 import jdk.internal.loader.BuiltinClassLoader;
67 import jdk.internal.misc.Unsafe;
68 import jdk.internal.module.Resources;
69 import jdk.internal.reflect.CallerSensitive;
70 import jdk.internal.reflect.ConstantPool;
71 import jdk.internal.reflect.Reflection;
72 import jdk.internal.reflect.ReflectionFactory;
73 import jdk.internal.vm.annotation.ForceInline;
74 import sun.reflect.generics.factory.CoreReflectionFactory;
75 import sun.reflect.generics.factory.GenericsFactory;
76 import sun.reflect.generics.repository.ClassRepository;
77 import sun.reflect.generics.repository.MethodRepository;
78 import sun.reflect.generics.repository.ConstructorRepository;
79 import sun.reflect.generics.scope.ClassScope;
80 import sun.security.util.SecurityConstants;
81 import sun.reflect.annotation.*;
82 import sun.reflect.misc.ReflectUtil;
83
84 /**
85 * Instances of the class {@code Class} represent classes and interfaces
86 * in a running Java application. An enum type is a kind of class and an
87 * annotation type is a kind of interface. Every array also
88 * belongs to a class that is reflected as a {@code Class} object
89 * that is shared by all arrays with the same element type and number
90 * of dimensions. The primitive Java types ({@code boolean},
91 * {@code byte}, {@code char}, {@code short},
92 * {@code int}, {@code long}, {@code float}, and
93 * {@code double}), and the keyword {@code void} are also
94 * represented as {@code Class} objects.
95 *
96 * <p> {@code Class} has no public constructor. Instead a {@code Class}
97 * object is constructed automatically by the Java Virtual Machine
98 * when a class loader invokes one of the
99 * {@link ClassLoader#defineClass(String,byte[], int,int) defineClass} methods
100 * and passes the bytes of a {@code class} file.
101 *
102 * <p> The methods of class {@code Class} expose many characteristics of a
103 * class or interface. Most characteristics are derived from the {@code class}
104 * file that the class loader passed to the Java Virtual Machine. A few
105 * characteristics are determined by the class loading environment at run time,
106 * such as the module returned by {@link #getModule() getModule()}.
107 *
108 * <p> Some methods of class {@code Class} expose whether the declaration of
109 * a class or interface in Java source code was <em>enclosed</em> within
110 * another declaration. Other methods describe how a class or interface
111 * is situated in a <em>nest</em>. A <a id="nest">nest</a> is a set of
112 * classes and interfaces, in the same run-time package, that
113 * allow mutual access to their {@code private} members.
114 * The classes and interfaces are known as <em>nestmates</em>.
115 * One nestmate acts as the
116 * <em>nest host</em>, and enumerates the other nestmates which
117 * belong to the nest; each of them in turn records it as the nest host.
118 * The classes and interfaces which belong to a nest, including its host, are
119 * determined when
120 * {@code class} files are generated, for example, a Java compiler
121 * will typically record a top-level class as the host of a nest where the
122 * other members are the classes and interfaces whose declarations are
123 * enclosed within the top-level class declaration.
124 *
125 * <p> The following example uses a {@code Class} object to print the
126 * class name of an object:
127 *
128 * <blockquote><pre>
129 * void printClassName(Object obj) {
130 * System.out.println("The class of " + obj +
131 * " is " + obj.getClass().getName());
132 * }
133 * </pre></blockquote>
134 *
135 * <p> It is also possible to get the {@code Class} object for a named
136 * type (or for void) using a class literal. See Section 15.8.2 of
137 * <cite>The Java™ Language Specification</cite>.
138 * For example:
139 *
140 * <blockquote>
141 * {@code System.out.println("The name of class Foo is: "+Foo.class.getName());}
142 * </blockquote>
143 *
144 * @param <T> the type of the class modeled by this {@code Class}
145 * object. For example, the type of {@code String.class} is {@code
146 * Class<String>}. Use {@code Class<?>} if the class being modeled is
147 * unknown.
148 *
149 * @author unascribed
150 * @see java.lang.ClassLoader#defineClass(byte[], int, int)
151 * @since 1.0
152 */
153 public final class Class<T> implements java.io.Serializable,
154 GenericDeclaration,
155 Type,
156 AnnotatedElement {
157 private static final int ANNOTATION = 0x00002000;
158 private static final int ENUM = 0x00004000;
159 private static final int SYNTHETIC = 0x00001000;
160 private static final int VALUE_TYPE = 0x00000100;
161
162 private static native void registerNatives();
163 static {
164 registerNatives();
165 }
166
167 /*
168 * Private constructor. Only the Java Virtual Machine creates Class objects.
169 * This constructor is not used and prevents the default constructor being
170 * generated.
171 */
172 private Class(ClassLoader loader, Class<?> arrayComponentType) {
173 // Initialize final field for classLoader. The initialization value of non-null
174 // prevents future JIT optimizations from assuming this final field is null.
175 classLoader = loader;
176 componentType = arrayComponentType;
177 }
178
179 /**
180 * Converts the object to a string. The string representation is the
181 * string "class" or "interface", followed by a space, and then by the
182 * fully qualified name of the class in the format returned by
183 * {@code getName}. If this {@code Class} object represents a
184 * primitive type, this method returns the name of the primitive type. If
185 * this {@code Class} object represents void this method returns
186 * "void". If this {@code Class} object represents an array type,
187 * this method returns "class " followed by {@code getName}.
188 *
189 * @return a string representation of this class object.
190 */
191 public String toString() {
192 return (isInterface() ? "interface " : (isPrimitive() ? "" : "class "))
193 + getName();
194 }
195
196 /**
197 * Returns a string describing this {@code Class}, including
198 * information about modifiers and type parameters.
199 *
200 * The string is formatted as a list of type modifiers, if any,
201 * followed by the kind of type (empty string for primitive types
202 * and {@code class}, {@code enum}, {@code interface}, or
203 * <code>@</code>{@code interface}, as appropriate), followed
204 * by the type's name, followed by an angle-bracketed
205 * comma-separated list of the type's type parameters, if any.
206 *
207 * A space is used to separate modifiers from one another and to
208 * separate any modifiers from the kind of type. The modifiers
209 * occur in canonical order. If there are no type parameters, the
210 * type parameter list is elided.
211 *
212 * For an array type, the string starts with the type name,
213 * followed by an angle-bracketed comma-separated list of the
214 * type's type parameters, if any, followed by a sequence of
215 * {@code []} characters, one set of brackets per dimension of
216 * the array.
217 *
218 * <p>Note that since information about the runtime representation
219 * of a type is being generated, modifiers not present on the
220 * originating source code or illegal on the originating source
221 * code may be present.
222 *
223 * @return a string describing this {@code Class}, including
224 * information about modifiers and type parameters
225 *
226 * @since 1.8
227 */
228 public String toGenericString() {
229 if (isPrimitive()) {
230 return toString();
231 } else {
232 StringBuilder sb = new StringBuilder();
233 Class<?> component = this;
234 int arrayDepth = 0;
235
236 if (isArray()) {
237 do {
238 arrayDepth++;
239 component = component.getComponentType();
240 } while (component.isArray());
241 sb.append(component.getName());
242 } else {
243 // Class modifiers are a superset of interface modifiers
244 int modifiers = getModifiers() & Modifier.classModifiers();
245 if (modifiers != 0) {
246 sb.append(Modifier.toString(modifiers));
247 sb.append(' ');
248 }
249
250 if (isAnnotation()) {
251 sb.append('@');
252 }
253 if (isInterface()) { // Note: all annotation types are interfaces
254 sb.append("interface");
255 } else {
256 if (isEnum())
257 sb.append("enum");
258 else
259 sb.append("class");
260 }
261 sb.append(' ');
262 sb.append(getName());
263 }
264
265 TypeVariable<?>[] typeparms = component.getTypeParameters();
266 if (typeparms.length > 0) {
267 StringJoiner sj = new StringJoiner(",", "<", ">");
268 for(TypeVariable<?> typeparm: typeparms) {
269 sj.add(typeparm.getTypeName());
270 }
271 sb.append(sj.toString());
272 }
273
274 for (int i = 0; i < arrayDepth; i++)
275 sb.append("[]");
276
277 return sb.toString();
278 }
279 }
280
281 /**
282 * Returns the {@code Class} object associated with the class or
283 * interface with the given string name. Invoking this method is
284 * equivalent to:
285 *
286 * <blockquote>
287 * {@code Class.forName(className, true, currentLoader)}
288 * </blockquote>
289 *
290 * where {@code currentLoader} denotes the defining class loader of
291 * the current class.
292 *
293 * <p> For example, the following code fragment returns the
294 * runtime {@code Class} descriptor for the class named
295 * {@code java.lang.Thread}:
296 *
297 * <blockquote>
298 * {@code Class t = Class.forName("java.lang.Thread")}
299 * </blockquote>
300 * <p>
301 * A call to {@code forName("X")} causes the class named
302 * {@code X} to be initialized.
303 *
304 * @param className the fully qualified name of the desired class.
305 * @return the {@code Class} object for the class with the
306 * specified name.
307 * @exception LinkageError if the linkage fails
308 * @exception ExceptionInInitializerError if the initialization provoked
309 * by this method fails
310 * @exception ClassNotFoundException if the class cannot be located
311 */
312 @CallerSensitive
313 public static Class<?> forName(String className)
314 throws ClassNotFoundException {
315 Class<?> caller = Reflection.getCallerClass();
316 return forName0(className, true, ClassLoader.getClassLoader(caller), caller);
317 }
318
319
320 /**
321 * Returns the {@code Class} object associated with the class or
322 * interface with the given string name, using the given class loader.
323 * Given the fully qualified name for a class or interface (in the same
324 * format returned by {@code getName}) this method attempts to
325 * locate, load, and link the class or interface. The specified class
326 * loader is used to load the class or interface. If the parameter
327 * {@code loader} is null, the class is loaded through the bootstrap
328 * class loader. The class is initialized only if the
329 * {@code initialize} parameter is {@code true} and if it has
330 * not been initialized earlier.
331 *
332 * <p> If {@code name} denotes a primitive type or void, an attempt
333 * will be made to locate a user-defined class in the unnamed package whose
334 * name is {@code name}. Therefore, this method cannot be used to
335 * obtain any of the {@code Class} objects representing primitive
336 * types or void.
337 *
338 * <p> If {@code name} denotes an array class, the component type of
339 * the array class is loaded but not initialized.
340 *
341 * <p> For example, in an instance method the expression:
342 *
343 * <blockquote>
344 * {@code Class.forName("Foo")}
345 * </blockquote>
346 *
347 * is equivalent to:
348 *
349 * <blockquote>
350 * {@code Class.forName("Foo", true, this.getClass().getClassLoader())}
351 * </blockquote>
352 *
353 * Note that this method throws errors related to loading, linking or
354 * initializing as specified in Sections 12.2, 12.3 and 12.4 of <em>The
355 * Java Language Specification</em>.
356 * Note that this method does not check whether the requested class
357 * is accessible to its caller.
358 *
359 * @param name fully qualified name of the desired class
360 * @param initialize if {@code true} the class will be initialized.
361 * See Section 12.4 of <em>The Java Language Specification</em>.
362 * @param loader class loader from which the class must be loaded
363 * @return class object representing the desired class
364 *
365 * @exception LinkageError if the linkage fails
366 * @exception ExceptionInInitializerError if the initialization provoked
367 * by this method fails
368 * @exception ClassNotFoundException if the class cannot be located by
369 * the specified class loader
370 * @exception SecurityException
371 * if a security manager is present, and the {@code loader} is
372 * {@code null}, and the caller's class loader is not
373 * {@code null}, and the caller does not have the
374 * {@link RuntimePermission}{@code ("getClassLoader")}
375 *
376 * @see java.lang.Class#forName(String)
377 * @see java.lang.ClassLoader
378 * @since 1.2
379 */
380 @CallerSensitive
381 public static Class<?> forName(String name, boolean initialize,
382 ClassLoader loader)
383 throws ClassNotFoundException
384 {
385 Class<?> caller = null;
386 SecurityManager sm = System.getSecurityManager();
387 if (sm != null) {
388 // Reflective call to get caller class is only needed if a security manager
389 // is present. Avoid the overhead of making this call otherwise.
390 caller = Reflection.getCallerClass();
391 if (loader == null) {
392 ClassLoader ccl = ClassLoader.getClassLoader(caller);
393 if (ccl != null) {
394 sm.checkPermission(
395 SecurityConstants.GET_CLASSLOADER_PERMISSION);
396 }
397 }
398 }
399 return forName0(name, initialize, loader, caller);
400 }
401
402 /** Called after security check for system loader access checks have been made. */
403 private static native Class<?> forName0(String name, boolean initialize,
404 ClassLoader loader,
405 Class<?> caller)
406 throws ClassNotFoundException;
407
408
409 /**
410 * Returns the {@code Class} with the given <a href="ClassLoader.html#name">
411 * binary name</a> in the given module.
412 *
413 * <p> This method attempts to locate, load, and link the class or interface.
414 * It does not run the class initializer. If the class is not found, this
415 * method returns {@code null}. </p>
416 *
417 * <p> If the class loader of the given module defines other modules and
418 * the given name is a class defined in a different module, this method
419 * returns {@code null} after the class is loaded. </p>
420 *
421 * <p> This method does not check whether the requested class is
422 * accessible to its caller. </p>
423 *
424 * @apiNote
425 * This method returns {@code null} on failure rather than
426 * throwing a {@link ClassNotFoundException}, as is done by
427 * the {@link #forName(String, boolean, ClassLoader)} method.
428 * The security check is a stack-based permission check if the caller
429 * loads a class in another module.
430 *
431 * @param module A module
432 * @param name The <a href="ClassLoader.html#name">binary name</a>
433 * of the class
434 * @return {@code Class} object of the given name defined in the given module;
435 * {@code null} if not found.
436 *
437 * @throws NullPointerException if the given module or name is {@code null}
438 *
439 * @throws LinkageError if the linkage fails
440 *
441 * @throws SecurityException
442 * <ul>
443 * <li> if the caller is not the specified module and
444 * {@code RuntimePermission("getClassLoader")} permission is denied; or</li>
445 * <li> access to the module content is denied. For example,
446 * permission check will be performed when a class loader calls
447 * {@link ModuleReader#open(String)} to read the bytes of a class file
448 * in a module.</li>
449 * </ul>
450 *
451 * @since 9
452 * @spec JPMS
453 */
454 @CallerSensitive
455 public static Class<?> forName(Module module, String name) {
456 Objects.requireNonNull(module);
457 Objects.requireNonNull(name);
458
459 ClassLoader cl;
460 SecurityManager sm = System.getSecurityManager();
461 if (sm != null) {
462 Class<?> caller = Reflection.getCallerClass();
463 if (caller != null && caller.getModule() != module) {
464 // if caller is null, Class.forName is the last java frame on the stack.
465 // java.base has all permissions
466 sm.checkPermission(SecurityConstants.GET_CLASSLOADER_PERMISSION);
467 }
468 PrivilegedAction<ClassLoader> pa = module::getClassLoader;
469 cl = AccessController.doPrivileged(pa);
470 } else {
471 cl = module.getClassLoader();
472 }
473
474 if (cl != null) {
475 return cl.loadClass(module, name);
476 } else {
477 return BootLoader.loadClass(module, name);
478 }
479 }
480
481
482 /**
483 * Returns {@code true} if this class is a value class.
484 *
485 * @return {@code true} if this class is a value class.
486 */
487 public boolean isValue() {
488 int mods = this.getModifiers();
489 if ((mods & VALUE_TYPE) != 0) {
490 if ((mods & (Modifier.INTERFACE | Modifier.ABSTRACT)) != 0) {
491 throw new InternalError("value class can't have ACC_INTERFACE or ACC_ABSTRACT set");
492 }
493 if (getSuperclass() != Object.class) {
494 throw new InternalError("Super class of a value class must be java.lang.Object");
495 }
496 return true;
497 }
498 return false;
499 }
500
501 /**
502 * Creates a new instance of the class represented by this {@code Class}
503 * object. The class is instantiated as if by a {@code new}
504 * expression with an empty argument list. The class is initialized if it
505 * has not already been initialized.
506 *
507 * @deprecated This method propagates any exception thrown by the
508 * nullary constructor, including a checked exception. Use of
509 * this method effectively bypasses the compile-time exception
510 * checking that would otherwise be performed by the compiler.
511 * The {@link
512 * java.lang.reflect.Constructor#newInstance(java.lang.Object...)
513 * Constructor.newInstance} method avoids this problem by wrapping
514 * any exception thrown by the constructor in a (checked) {@link
515 * java.lang.reflect.InvocationTargetException}.
516 *
517 * <p>The call
518 *
519 * <pre>{@code
520 * clazz.newInstance()
521 * }</pre>
522 *
523 * can be replaced by
524 *
525 * <pre>{@code
526 * clazz.getDeclaredConstructor().newInstance()
527 * }</pre>
528 *
529 * The latter sequence of calls is inferred to be able to throw
530 * the additional exception types {@link
531 * InvocationTargetException} and {@link
532 * NoSuchMethodException}. Both of these exception types are
533 * subclasses of {@link ReflectiveOperationException}.
534 *
535 * @return a newly allocated instance of the class represented by this
536 * object.
537 * @throws IllegalAccessException if the class or its nullary
538 * constructor is not accessible.
539 * @throws InstantiationException
540 * if this {@code Class} represents an abstract class,
541 * an interface, an array class, a primitive type, or void;
542 * or if the class has no nullary constructor;
543 * or if the instantiation fails for some other reason.
544 * @throws ExceptionInInitializerError if the initialization
545 * provoked by this method fails.
546 * @throws SecurityException
547 * If a security manager, <i>s</i>, is present and
548 * the caller's class loader is not the same as or an
549 * ancestor of the class loader for the current class and
550 * invocation of {@link SecurityManager#checkPackageAccess
551 * s.checkPackageAccess()} denies access to the package
552 * of this class.
553 */
554 @CallerSensitive
555 @Deprecated(since="9")
556 public T newInstance()
557 throws InstantiationException, IllegalAccessException
558 {
559 if (this.isValue()) {
560 throw new IllegalAccessException(
561 "cannot create new instance of value class " + this.getName());
562 }
563
564 SecurityManager sm = System.getSecurityManager();
565 if (sm != null) {
566 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), false);
567 }
568
569 // NOTE: the following code may not be strictly correct under
570 // the current Java memory model.
571
572 // Constructor lookup
573 if (cachedConstructor == null) {
574 if (this == Class.class) {
575 throw new IllegalAccessException(
576 "Can not call newInstance() on the Class for java.lang.Class"
577 );
578 }
579 try {
580 Class<?>[] empty = {};
581 final Constructor<T> c = getReflectionFactory().copyConstructor(
582 getConstructor0(empty, Member.DECLARED));
583 // Disable accessibility checks on the constructor
584 // since we have to do the security check here anyway
585 // (the stack depth is wrong for the Constructor's
586 // security check to work)
587 java.security.AccessController.doPrivileged(
588 new java.security.PrivilegedAction<>() {
589 public Void run() {
590 c.setAccessible(true);
591 return null;
592 }
593 });
594 cachedConstructor = c;
595 } catch (NoSuchMethodException e) {
596 throw (InstantiationException)
597 new InstantiationException(getName()).initCause(e);
598 }
599 }
600 Constructor<T> tmpConstructor = cachedConstructor;
601 // Security check (same as in java.lang.reflect.Constructor)
602 Class<?> caller = Reflection.getCallerClass();
603 if (newInstanceCallerCache != caller) {
604 int modifiers = tmpConstructor.getModifiers();
605 Reflection.ensureMemberAccess(caller, this, this, modifiers);
606 newInstanceCallerCache = caller;
607 }
608 // Run constructor
609 try {
610 return tmpConstructor.newInstance((Object[])null);
611 } catch (InvocationTargetException e) {
612 Unsafe.getUnsafe().throwException(e.getTargetException());
613 // Not reached
614 return null;
615 }
616 }
617 private transient volatile Constructor<T> cachedConstructor;
618 private transient volatile Class<?> newInstanceCallerCache;
619
620
621 /**
622 * Determines if the specified {@code Object} is assignment-compatible
623 * with the object represented by this {@code Class}. This method is
624 * the dynamic equivalent of the Java language {@code instanceof}
625 * operator. The method returns {@code true} if the specified
626 * {@code Object} argument is non-null and can be cast to the
627 * reference type represented by this {@code Class} object without
628 * raising a {@code ClassCastException.} It returns {@code false}
629 * otherwise.
630 *
631 * <p> Specifically, if this {@code Class} object represents a
632 * declared class, this method returns {@code true} if the specified
633 * {@code Object} argument is an instance of the represented class (or
634 * of any of its subclasses); it returns {@code false} otherwise. If
635 * this {@code Class} object represents an array class, this method
636 * returns {@code true} if the specified {@code Object} argument
637 * can be converted to an object of the array class by an identity
638 * conversion or by a widening reference conversion; it returns
639 * {@code false} otherwise. If this {@code Class} object
640 * represents an interface, this method returns {@code true} if the
641 * class or any superclass of the specified {@code Object} argument
642 * implements this interface; it returns {@code false} otherwise. If
643 * this {@code Class} object represents a primitive type, this method
644 * returns {@code false}.
645 *
646 * @param obj the object to check
647 * @return true if {@code obj} is an instance of this class
648 *
649 * @since 1.1
650 */
651 @HotSpotIntrinsicCandidate
652 public native boolean isInstance(Object obj);
653
654
655 /**
656 * Determines if the class or interface represented by this
657 * {@code Class} object is either the same as, or is a superclass or
658 * superinterface of, the class or interface represented by the specified
659 * {@code Class} parameter. It returns {@code true} if so;
660 * otherwise it returns {@code false}. If this {@code Class}
661 * object represents a primitive type, this method returns
662 * {@code true} if the specified {@code Class} parameter is
663 * exactly this {@code Class} object; otherwise it returns
664 * {@code false}.
665 *
666 * <p> Specifically, this method tests whether the type represented by the
667 * specified {@code Class} parameter can be converted to the type
668 * represented by this {@code Class} object via an identity conversion
669 * or via a widening reference conversion. See <em>The Java Language
670 * Specification</em>, sections 5.1.1 and 5.1.4 , for details.
671 *
672 * @param cls the {@code Class} object to be checked
673 * @return the {@code boolean} value indicating whether objects of the
674 * type {@code cls} can be assigned to objects of this class
675 * @exception NullPointerException if the specified Class parameter is
676 * null.
677 * @since 1.1
678 */
679 @HotSpotIntrinsicCandidate
680 public native boolean isAssignableFrom(Class<?> cls);
681
682
683 /**
684 * Determines if the specified {@code Class} object represents an
685 * interface type.
686 *
687 * @return {@code true} if this object represents an interface;
688 * {@code false} otherwise.
689 */
690 @HotSpotIntrinsicCandidate
691 public native boolean isInterface();
692
693
694 /**
695 * Determines if this {@code Class} object represents an array class.
696 *
697 * @return {@code true} if this object represents an array class;
698 * {@code false} otherwise.
699 * @since 1.1
700 */
701 @HotSpotIntrinsicCandidate
702 public native boolean isArray();
703
704
705 /**
706 * Determines if the specified {@code Class} object represents a
707 * primitive type.
708 *
709 * <p> There are nine predefined {@code Class} objects to represent
710 * the eight primitive types and void. These are created by the Java
711 * Virtual Machine, and have the same names as the primitive types that
712 * they represent, namely {@code boolean}, {@code byte},
713 * {@code char}, {@code short}, {@code int},
714 * {@code long}, {@code float}, and {@code double}.
715 *
716 * <p> These objects may only be accessed via the following public static
717 * final variables, and are the only {@code Class} objects for which
718 * this method returns {@code true}.
719 *
720 * @return true if and only if this class represents a primitive type
721 *
722 * @see java.lang.Boolean#TYPE
723 * @see java.lang.Character#TYPE
724 * @see java.lang.Byte#TYPE
725 * @see java.lang.Short#TYPE
726 * @see java.lang.Integer#TYPE
727 * @see java.lang.Long#TYPE
728 * @see java.lang.Float#TYPE
729 * @see java.lang.Double#TYPE
730 * @see java.lang.Void#TYPE
731 * @since 1.1
732 */
733 @HotSpotIntrinsicCandidate
734 public native boolean isPrimitive();
735
736 /**
737 * Returns true if this {@code Class} object represents an annotation
738 * type. Note that if this method returns true, {@link #isInterface()}
739 * would also return true, as all annotation types are also interfaces.
740 *
741 * @return {@code true} if this class object represents an annotation
742 * type; {@code false} otherwise
743 * @since 1.5
744 */
745 public boolean isAnnotation() {
746 return (getModifiers() & ANNOTATION) != 0;
747 }
748
749 /**
750 * Returns {@code true} if this class is a synthetic class;
751 * returns {@code false} otherwise.
752 * @return {@code true} if and only if this class is a synthetic class as
753 * defined by the Java Language Specification.
754 * @jls 13.1 The Form of a Binary
755 * @since 1.5
756 */
757 public boolean isSynthetic() {
758 return (getModifiers() & SYNTHETIC) != 0;
759 }
760
761 /**
762 * Returns the name of the entity (class, interface, array class,
763 * primitive type, or void) represented by this {@code Class} object,
764 * as a {@code String}.
765 *
766 * <p> If this class object represents a reference type that is not an
767 * array type then the binary name of the class is returned, as specified
768 * by
769 * <cite>The Java™ Language Specification</cite>.
770 *
771 * <p> If this class object represents a primitive type or void, then the
772 * name returned is a {@code String} equal to the Java language
773 * keyword corresponding to the primitive type or void.
774 *
775 * <p> If this class object represents a class of arrays, then the internal
776 * form of the name consists of the name of the element type preceded by
777 * one or more '{@code [}' characters representing the depth of the array
778 * nesting. The encoding of element type names is as follows:
779 *
780 * <blockquote><table class="striped">
781 * <caption style="display:none">Element types and encodings</caption>
782 * <thead>
783 * <tr><th scope="col"> Element Type <th scope="col"> Encoding
784 * </thead>
785 * <tbody style="text-align:left">
786 * <tr><th scope="row"> boolean <td style="text-align:center"> Z
787 * <tr><th scope="row"> byte <td style="text-align:center"> B
788 * <tr><th scope="row"> char <td style="text-align:center"> C
789 * <tr><th scope="row"> class or interface
790 * <td style="text-align:center"> L<i>classname</i>;
791 * <tr><th scope="row"> double <td style="text-align:center"> D
792 * <tr><th scope="row"> float <td style="text-align:center"> F
793 * <tr><th scope="row"> int <td style="text-align:center"> I
794 * <tr><th scope="row"> long <td style="text-align:center"> J
795 * <tr><th scope="row"> short <td style="text-align:center"> S
796 * </tbody>
797 * </table></blockquote>
798 *
799 * <p> The class or interface name <i>classname</i> is the binary name of
800 * the class specified above.
801 *
802 * <p> Examples:
803 * <blockquote><pre>
804 * String.class.getName()
805 * returns "java.lang.String"
806 * byte.class.getName()
807 * returns "byte"
808 * (new Object[3]).getClass().getName()
809 * returns "[Ljava.lang.Object;"
810 * (new int[3][4][5][6][7][8][9]).getClass().getName()
811 * returns "[[[[[[[I"
812 * </pre></blockquote>
813 *
814 * @return the name of the class or interface
815 * represented by this object.
816 */
817 public String getName() {
818 String name = this.name;
819 if (name == null)
820 this.name = name = getName0();
821 return name;
822 }
823
824 // cache the name to reduce the number of calls into the VM
825 private transient String name;
826 private native String getName0();
827
828 /**
829 * Returns the class loader for the class. Some implementations may use
830 * null to represent the bootstrap class loader. This method will return
831 * null in such implementations if this class was loaded by the bootstrap
832 * class loader.
833 *
834 * <p>If this object
835 * represents a primitive type or void, null is returned.
836 *
837 * @return the class loader that loaded the class or interface
838 * represented by this object.
839 * @throws SecurityException
840 * if a security manager is present, and the caller's class loader
841 * is not {@code null} and is not the same as or an ancestor of the
842 * class loader for the class whose class loader is requested,
843 * and the caller does not have the
844 * {@link RuntimePermission}{@code ("getClassLoader")}
845 * @see java.lang.ClassLoader
846 * @see SecurityManager#checkPermission
847 * @see java.lang.RuntimePermission
848 */
849 @CallerSensitive
850 @ForceInline // to ensure Reflection.getCallerClass optimization
851 public ClassLoader getClassLoader() {
852 ClassLoader cl = getClassLoader0();
853 if (cl == null)
854 return null;
855 SecurityManager sm = System.getSecurityManager();
856 if (sm != null) {
857 ClassLoader.checkClassLoaderPermission(cl, Reflection.getCallerClass());
858 }
859 return cl;
860 }
861
862 // Package-private to allow ClassLoader access
863 ClassLoader getClassLoader0() { return classLoader; }
864
865 /**
866 * Returns the module that this class or interface is a member of.
867 *
868 * If this class represents an array type then this method returns the
869 * {@code Module} for the element type. If this class represents a
870 * primitive type or void, then the {@code Module} object for the
871 * {@code java.base} module is returned.
872 *
873 * If this class is in an unnamed module then the {@linkplain
874 * ClassLoader#getUnnamedModule() unnamed} {@code Module} of the class
875 * loader for this class is returned.
876 *
877 * @return the module that this class or interface is a member of
878 *
879 * @since 9
880 * @spec JPMS
881 */
882 public Module getModule() {
883 return module;
884 }
885
886 // set by VM
887 private transient Module module;
888
889 // Initialized in JVM not by private constructor
890 // This field is filtered from reflection access, i.e. getDeclaredField
891 // will throw NoSuchFieldException
892 private final ClassLoader classLoader;
893
894 /**
895 * Returns an array of {@code TypeVariable} objects that represent the
896 * type variables declared by the generic declaration represented by this
897 * {@code GenericDeclaration} object, in declaration order. Returns an
898 * array of length 0 if the underlying generic declaration declares no type
899 * variables.
900 *
901 * @return an array of {@code TypeVariable} objects that represent
902 * the type variables declared by this generic declaration
903 * @throws java.lang.reflect.GenericSignatureFormatError if the generic
904 * signature of this generic declaration does not conform to
905 * the format specified in
906 * <cite>The Java™ Virtual Machine Specification</cite>
907 * @since 1.5
908 */
909 @SuppressWarnings("unchecked")
910 public TypeVariable<Class<T>>[] getTypeParameters() {
911 ClassRepository info = getGenericInfo();
912 if (info != null)
913 return (TypeVariable<Class<T>>[])info.getTypeParameters();
914 else
915 return (TypeVariable<Class<T>>[])new TypeVariable<?>[0];
916 }
917
918
919 /**
920 * Returns the {@code Class} representing the direct superclass of the
921 * entity (class, interface, primitive type or void) represented by
922 * this {@code Class}. If this {@code Class} represents either the
923 * {@code Object} class, an interface, a primitive type, or void, then
924 * null is returned. If this object represents an array class then the
925 * {@code Class} object representing the {@code Object} class is
926 * returned.
927 *
928 * @return the direct superclass of the class represented by this object
929 */
930 @HotSpotIntrinsicCandidate
931 public native Class<? super T> getSuperclass();
932
933
934 /**
935 * Returns the {@code Type} representing the direct superclass of
936 * the entity (class, interface, primitive type or void) represented by
937 * this {@code Class}.
938 *
939 * <p>If the superclass is a parameterized type, the {@code Type}
940 * object returned must accurately reflect the actual type
941 * parameters used in the source code. The parameterized type
942 * representing the superclass is created if it had not been
943 * created before. See the declaration of {@link
944 * java.lang.reflect.ParameterizedType ParameterizedType} for the
945 * semantics of the creation process for parameterized types. If
946 * this {@code Class} represents either the {@code Object}
947 * class, an interface, a primitive type, or void, then null is
948 * returned. If this object represents an array class then the
949 * {@code Class} object representing the {@code Object} class is
950 * returned.
951 *
952 * @throws java.lang.reflect.GenericSignatureFormatError if the generic
953 * class signature does not conform to the format specified in
954 * <cite>The Java™ Virtual Machine Specification</cite>
955 * @throws TypeNotPresentException if the generic superclass
956 * refers to a non-existent type declaration
957 * @throws java.lang.reflect.MalformedParameterizedTypeException if the
958 * generic superclass refers to a parameterized type that cannot be
959 * instantiated for any reason
960 * @return the direct superclass of the class represented by this object
961 * @since 1.5
962 */
963 public Type getGenericSuperclass() {
964 ClassRepository info = getGenericInfo();
965 if (info == null) {
966 return getSuperclass();
967 }
968
969 // Historical irregularity:
970 // Generic signature marks interfaces with superclass = Object
971 // but this API returns null for interfaces
972 if (isInterface()) {
973 return null;
974 }
975
976 return info.getSuperclass();
977 }
978
979 /**
980 * Gets the package of this class.
981 *
982 * <p>If this class represents an array type, a primitive type or void,
983 * this method returns {@code null}.
984 *
985 * @return the package of this class.
986 * @revised 9
987 * @spec JPMS
988 */
989 public Package getPackage() {
990 if (isPrimitive() || isArray()) {
991 return null;
992 }
993 ClassLoader cl = getClassLoader0();
994 return cl != null ? cl.definePackage(this)
995 : BootLoader.definePackage(this);
996 }
997
998 /**
999 * Returns the fully qualified package name.
1000 *
1001 * <p> If this class is a top level class, then this method returns the fully
1002 * qualified name of the package that the class is a member of, or the
1003 * empty string if the class is in an unnamed package.
1004 *
1005 * <p> If this class is a member class, then this method is equivalent to
1006 * invoking {@code getPackageName()} on the {@linkplain #getEnclosingClass
1007 * enclosing class}.
1008 *
1009 * <p> If this class is a {@linkplain #isLocalClass local class} or an {@linkplain
1010 * #isAnonymousClass() anonymous class}, then this method is equivalent to
1011 * invoking {@code getPackageName()} on the {@linkplain #getDeclaringClass
1012 * declaring class} of the {@linkplain #getEnclosingMethod enclosing method} or
1013 * {@linkplain #getEnclosingConstructor enclosing constructor}.
1014 *
1015 * <p> If this class represents an array type then this method returns the
1016 * package name of the element type. If this class represents a primitive
1017 * type or void then the package name "{@code java.lang}" is returned.
1018 *
1019 * @return the fully qualified package name
1020 *
1021 * @since 9
1022 * @spec JPMS
1023 * @jls 6.7 Fully Qualified Names
1024 */
1025 public String getPackageName() {
1026 String pn = this.packageName;
1027 if (pn == null) {
1028 Class<?> c = this;
1029 while (c.isArray()) {
1030 c = c.getComponentType();
1031 }
1032 if (c.isPrimitive()) {
1033 pn = "java.lang";
1034 } else {
1035 String cn = c.getName();
1036 int dot = cn.lastIndexOf('.');
1037 pn = (dot != -1) ? cn.substring(0, dot).intern() : "";
1038 }
1039 this.packageName = pn;
1040 }
1041 return pn;
1042 }
1043
1044 // cached package name
1045 private transient String packageName;
1046
1047 /**
1048 * Returns the interfaces directly implemented by the class or interface
1049 * represented by this object.
1050 *
1051 * <p>If this object represents a class, the return value is an array
1052 * containing objects representing all interfaces directly implemented by
1053 * the class. The order of the interface objects in the array corresponds
1054 * to the order of the interface names in the {@code implements} clause of
1055 * the declaration of the class represented by this object. For example,
1056 * given the declaration:
1057 * <blockquote>
1058 * {@code class Shimmer implements FloorWax, DessertTopping { ... }}
1059 * </blockquote>
1060 * suppose the value of {@code s} is an instance of
1061 * {@code Shimmer}; the value of the expression:
1062 * <blockquote>
1063 * {@code s.getClass().getInterfaces()[0]}
1064 * </blockquote>
1065 * is the {@code Class} object that represents interface
1066 * {@code FloorWax}; and the value of:
1067 * <blockquote>
1068 * {@code s.getClass().getInterfaces()[1]}
1069 * </blockquote>
1070 * is the {@code Class} object that represents interface
1071 * {@code DessertTopping}.
1072 *
1073 * <p>If this object represents an interface, the array contains objects
1074 * representing all interfaces directly extended by the interface. The
1075 * order of the interface objects in the array corresponds to the order of
1076 * the interface names in the {@code extends} clause of the declaration of
1077 * the interface represented by this object.
1078 *
1079 * <p>If this object represents a class or interface that implements no
1080 * interfaces, the method returns an array of length 0.
1081 *
1082 * <p>If this object represents a primitive type or void, the method
1083 * returns an array of length 0.
1084 *
1085 * <p>If this {@code Class} object represents an array type, the
1086 * interfaces {@code Cloneable} and {@code java.io.Serializable} are
1087 * returned in that order.
1088 *
1089 * @return an array of interfaces directly implemented by this class
1090 */
1091 public Class<?>[] getInterfaces() {
1092 // defensively copy before handing over to user code
1093 return getInterfaces(true);
1094 }
1095
1096 private Class<?>[] getInterfaces(boolean cloneArray) {
1097 ReflectionData<T> rd = reflectionData();
1098 if (rd == null) {
1099 // no cloning required
1100 return getInterfaces0();
1101 } else {
1102 Class<?>[] interfaces = rd.interfaces;
1103 if (interfaces == null) {
1104 interfaces = getInterfaces0();
1105 rd.interfaces = interfaces;
1106 }
1107 // defensively copy if requested
1108 return cloneArray ? interfaces.clone() : interfaces;
1109 }
1110 }
1111
1112 private native Class<?>[] getInterfaces0();
1113
1114 /**
1115 * Returns the {@code Type}s representing the interfaces
1116 * directly implemented by the class or interface represented by
1117 * this object.
1118 *
1119 * <p>If a superinterface is a parameterized type, the
1120 * {@code Type} object returned for it must accurately reflect
1121 * the actual type parameters used in the source code. The
1122 * parameterized type representing each superinterface is created
1123 * if it had not been created before. See the declaration of
1124 * {@link java.lang.reflect.ParameterizedType ParameterizedType}
1125 * for the semantics of the creation process for parameterized
1126 * types.
1127 *
1128 * <p>If this object represents a class, the return value is an array
1129 * containing objects representing all interfaces directly implemented by
1130 * the class. The order of the interface objects in the array corresponds
1131 * to the order of the interface names in the {@code implements} clause of
1132 * the declaration of the class represented by this object.
1133 *
1134 * <p>If this object represents an interface, the array contains objects
1135 * representing all interfaces directly extended by the interface. The
1136 * order of the interface objects in the array corresponds to the order of
1137 * the interface names in the {@code extends} clause of the declaration of
1138 * the interface represented by this object.
1139 *
1140 * <p>If this object represents a class or interface that implements no
1141 * interfaces, the method returns an array of length 0.
1142 *
1143 * <p>If this object represents a primitive type or void, the method
1144 * returns an array of length 0.
1145 *
1146 * <p>If this {@code Class} object represents an array type, the
1147 * interfaces {@code Cloneable} and {@code java.io.Serializable} are
1148 * returned in that order.
1149 *
1150 * @throws java.lang.reflect.GenericSignatureFormatError
1151 * if the generic class signature does not conform to the format
1152 * specified in
1153 * <cite>The Java™ Virtual Machine Specification</cite>
1154 * @throws TypeNotPresentException if any of the generic
1155 * superinterfaces refers to a non-existent type declaration
1156 * @throws java.lang.reflect.MalformedParameterizedTypeException
1157 * if any of the generic superinterfaces refer to a parameterized
1158 * type that cannot be instantiated for any reason
1159 * @return an array of interfaces directly implemented by this class
1160 * @since 1.5
1161 */
1162 public Type[] getGenericInterfaces() {
1163 ClassRepository info = getGenericInfo();
1164 return (info == null) ? getInterfaces() : info.getSuperInterfaces();
1165 }
1166
1167
1168 /**
1169 * Returns the {@code Class} representing the component type of an
1170 * array. If this class does not represent an array class this method
1171 * returns null.
1172 *
1173 * @return the {@code Class} representing the component type of this
1174 * class if this class is an array
1175 * @see java.lang.reflect.Array
1176 * @since 1.1
1177 */
1178 public Class<?> getComponentType() {
1179 // Only return for array types. Storage may be reused for Class for instance types.
1180 if (isArray()) {
1181 return componentType;
1182 } else {
1183 return null;
1184 }
1185 }
1186
1187 private final Class<?> componentType;
1188
1189
1190 /**
1191 * Returns the Java language modifiers for this class or interface, encoded
1192 * in an integer. The modifiers consist of the Java Virtual Machine's
1193 * constants for {@code public}, {@code protected},
1194 * {@code private}, {@code final}, {@code static},
1195 * {@code abstract} and {@code interface}; they should be decoded
1196 * using the methods of class {@code Modifier}.
1197 *
1198 * <p> If the underlying class is an array class, then its
1199 * {@code public}, {@code private} and {@code protected}
1200 * modifiers are the same as those of its component type. If this
1201 * {@code Class} represents a primitive type or void, its
1202 * {@code public} modifier is always {@code true}, and its
1203 * {@code protected} and {@code private} modifiers are always
1204 * {@code false}. If this object represents an array class, a
1205 * primitive type or void, then its {@code final} modifier is always
1206 * {@code true} and its interface modifier is always
1207 * {@code false}. The values of its other modifiers are not determined
1208 * by this specification.
1209 *
1210 * <p> The modifier encodings are defined in <em>The Java Virtual Machine
1211 * Specification</em>, table 4.1.
1212 *
1213 * @return the {@code int} representing the modifiers for this class
1214 * @see java.lang.reflect.Modifier
1215 * @since 1.1
1216 */
1217 @HotSpotIntrinsicCandidate
1218 public native int getModifiers();
1219
1220
1221 /**
1222 * Gets the signers of this class.
1223 *
1224 * @return the signers of this class, or null if there are no signers. In
1225 * particular, this method returns null if this object represents
1226 * a primitive type or void.
1227 * @since 1.1
1228 */
1229 public native Object[] getSigners();
1230
1231
1232 /**
1233 * Set the signers of this class.
1234 */
1235 native void setSigners(Object[] signers);
1236
1237
1238 /**
1239 * If this {@code Class} object represents a local or anonymous
1240 * class within a method, returns a {@link
1241 * java.lang.reflect.Method Method} object representing the
1242 * immediately enclosing method of the underlying class. Returns
1243 * {@code null} otherwise.
1244 *
1245 * In particular, this method returns {@code null} if the underlying
1246 * class is a local or anonymous class immediately enclosed by a type
1247 * declaration, instance initializer or static initializer.
1248 *
1249 * @return the immediately enclosing method of the underlying class, if
1250 * that class is a local or anonymous class; otherwise {@code null}.
1251 *
1252 * @throws SecurityException
1253 * If a security manager, <i>s</i>, is present and any of the
1254 * following conditions is met:
1255 *
1256 * <ul>
1257 *
1258 * <li> the caller's class loader is not the same as the
1259 * class loader of the enclosing class and invocation of
1260 * {@link SecurityManager#checkPermission
1261 * s.checkPermission} method with
1262 * {@code RuntimePermission("accessDeclaredMembers")}
1263 * denies access to the methods within the enclosing class
1264 *
1265 * <li> the caller's class loader is not the same as or an
1266 * ancestor of the class loader for the enclosing class and
1267 * invocation of {@link SecurityManager#checkPackageAccess
1268 * s.checkPackageAccess()} denies access to the package
1269 * of the enclosing class
1270 *
1271 * </ul>
1272 * @since 1.5
1273 */
1274 @CallerSensitive
1275 public Method getEnclosingMethod() throws SecurityException {
1276 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1277
1278 if (enclosingInfo == null)
1279 return null;
1280 else {
1281 if (!enclosingInfo.isMethod())
1282 return null;
1283
1284 MethodRepository typeInfo = MethodRepository.make(enclosingInfo.getDescriptor(),
1285 getFactory());
1286 Class<?> returnType = toClass(typeInfo.getReturnType());
1287 Type [] parameterTypes = typeInfo.getParameterTypes();
1288 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length];
1289
1290 // Convert Types to Classes; returned types *should*
1291 // be class objects since the methodDescriptor's used
1292 // don't have generics information
1293 for(int i = 0; i < parameterClasses.length; i++)
1294 parameterClasses[i] = toClass(parameterTypes[i]);
1295
1296 // Perform access check
1297 final Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass();
1298 SecurityManager sm = System.getSecurityManager();
1299 if (sm != null) {
1300 enclosingCandidate.checkMemberAccess(sm, Member.DECLARED,
1301 Reflection.getCallerClass(), true);
1302 }
1303 Method[] candidates = enclosingCandidate.privateGetDeclaredMethods(false);
1304
1305 /*
1306 * Loop over all declared methods; match method name,
1307 * number of and type of parameters, *and* return
1308 * type. Matching return type is also necessary
1309 * because of covariant returns, etc.
1310 */
1311 ReflectionFactory fact = getReflectionFactory();
1312 for (Method m : candidates) {
1313 if (m.getName().equals(enclosingInfo.getName()) &&
1314 arrayContentsEq(parameterClasses,
1315 fact.getExecutableSharedParameterTypes(m))) {
1316 // finally, check return type
1317 if (m.getReturnType().equals(returnType)) {
1318 return fact.copyMethod(m);
1319 }
1320 }
1321 }
1322
1323 throw new InternalError("Enclosing method not found");
1324 }
1325 }
1326
1327 private native Object[] getEnclosingMethod0();
1328
1329 private EnclosingMethodInfo getEnclosingMethodInfo() {
1330 Object[] enclosingInfo = getEnclosingMethod0();
1331 if (enclosingInfo == null)
1332 return null;
1333 else {
1334 return new EnclosingMethodInfo(enclosingInfo);
1335 }
1336 }
1337
1338 private static final class EnclosingMethodInfo {
1339 private final Class<?> enclosingClass;
1340 private final String name;
1341 private final String descriptor;
1342
1343 static void validate(Object[] enclosingInfo) {
1344 if (enclosingInfo.length != 3)
1345 throw new InternalError("Malformed enclosing method information");
1346 try {
1347 // The array is expected to have three elements:
1348
1349 // the immediately enclosing class
1350 Class<?> enclosingClass = (Class<?>)enclosingInfo[0];
1351 assert(enclosingClass != null);
1352
1353 // the immediately enclosing method or constructor's
1354 // name (can be null).
1355 String name = (String)enclosingInfo[1];
1356
1357 // the immediately enclosing method or constructor's
1358 // descriptor (null iff name is).
1359 String descriptor = (String)enclosingInfo[2];
1360 assert((name != null && descriptor != null) || name == descriptor);
1361 } catch (ClassCastException cce) {
1362 throw new InternalError("Invalid type in enclosing method information", cce);
1363 }
1364 }
1365
1366 EnclosingMethodInfo(Object[] enclosingInfo) {
1367 validate(enclosingInfo);
1368 this.enclosingClass = (Class<?>)enclosingInfo[0];
1369 this.name = (String)enclosingInfo[1];
1370 this.descriptor = (String)enclosingInfo[2];
1371 }
1372
1373 boolean isPartial() {
1374 return enclosingClass == null || name == null || descriptor == null;
1375 }
1376
1377 boolean isConstructor() { return !isPartial() && "<init>".equals(name); }
1378
1379 boolean isMethod() { return !isPartial() && !isConstructor() && !"<clinit>".equals(name); }
1380
1381 Class<?> getEnclosingClass() { return enclosingClass; }
1382
1383 String getName() { return name; }
1384
1385 String getDescriptor() { return descriptor; }
1386
1387 }
1388
1389 private static Class<?> toClass(Type o) {
1390 if (o instanceof GenericArrayType)
1391 return Array.newInstance(toClass(((GenericArrayType)o).getGenericComponentType()),
1392 0)
1393 .getClass();
1394 return (Class<?>)o;
1395 }
1396
1397 /**
1398 * If this {@code Class} object represents a local or anonymous
1399 * class within a constructor, returns a {@link
1400 * java.lang.reflect.Constructor Constructor} object representing
1401 * the immediately enclosing constructor of the underlying
1402 * class. Returns {@code null} otherwise. In particular, this
1403 * method returns {@code null} if the underlying class is a local
1404 * or anonymous class immediately enclosed by a type declaration,
1405 * instance initializer or static initializer.
1406 *
1407 * @return the immediately enclosing constructor of the underlying class, if
1408 * that class is a local or anonymous class; otherwise {@code null}.
1409 * @throws SecurityException
1410 * If a security manager, <i>s</i>, is present and any of the
1411 * following conditions is met:
1412 *
1413 * <ul>
1414 *
1415 * <li> the caller's class loader is not the same as the
1416 * class loader of the enclosing class and invocation of
1417 * {@link SecurityManager#checkPermission
1418 * s.checkPermission} method with
1419 * {@code RuntimePermission("accessDeclaredMembers")}
1420 * denies access to the constructors within the enclosing class
1421 *
1422 * <li> the caller's class loader is not the same as or an
1423 * ancestor of the class loader for the enclosing class and
1424 * invocation of {@link SecurityManager#checkPackageAccess
1425 * s.checkPackageAccess()} denies access to the package
1426 * of the enclosing class
1427 *
1428 * </ul>
1429 * @since 1.5
1430 */
1431 @CallerSensitive
1432 public Constructor<?> getEnclosingConstructor() throws SecurityException {
1433 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1434
1435 if (enclosingInfo == null)
1436 return null;
1437 else {
1438 if (!enclosingInfo.isConstructor())
1439 return null;
1440
1441 ConstructorRepository typeInfo = ConstructorRepository.make(enclosingInfo.getDescriptor(),
1442 getFactory());
1443 Type [] parameterTypes = typeInfo.getParameterTypes();
1444 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length];
1445
1446 // Convert Types to Classes; returned types *should*
1447 // be class objects since the methodDescriptor's used
1448 // don't have generics information
1449 for(int i = 0; i < parameterClasses.length; i++)
1450 parameterClasses[i] = toClass(parameterTypes[i]);
1451
1452 // Perform access check
1453 final Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass();
1454 SecurityManager sm = System.getSecurityManager();
1455 if (sm != null) {
1456 enclosingCandidate.checkMemberAccess(sm, Member.DECLARED,
1457 Reflection.getCallerClass(), true);
1458 }
1459
1460 Constructor<?>[] candidates = enclosingCandidate
1461 .privateGetDeclaredConstructors(false);
1462 /*
1463 * Loop over all declared constructors; match number
1464 * of and type of parameters.
1465 */
1466 ReflectionFactory fact = getReflectionFactory();
1467 for (Constructor<?> c : candidates) {
1468 if (arrayContentsEq(parameterClasses,
1469 fact.getExecutableSharedParameterTypes(c))) {
1470 return fact.copyConstructor(c);
1471 }
1472 }
1473
1474 throw new InternalError("Enclosing constructor not found");
1475 }
1476 }
1477
1478
1479 /**
1480 * If the class or interface represented by this {@code Class} object
1481 * is a member of another class, returns the {@code Class} object
1482 * representing the class in which it was declared. This method returns
1483 * null if this class or interface is not a member of any other class. If
1484 * this {@code Class} object represents an array class, a primitive
1485 * type, or void,then this method returns null.
1486 *
1487 * @return the declaring class for this class
1488 * @throws SecurityException
1489 * If a security manager, <i>s</i>, is present and the caller's
1490 * class loader is not the same as or an ancestor of the class
1491 * loader for the declaring class and invocation of {@link
1492 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
1493 * denies access to the package of the declaring class
1494 * @since 1.1
1495 */
1496 @CallerSensitive
1497 public Class<?> getDeclaringClass() throws SecurityException {
1498 final Class<?> candidate = getDeclaringClass0();
1499
1500 if (candidate != null) {
1501 SecurityManager sm = System.getSecurityManager();
1502 if (sm != null) {
1503 candidate.checkPackageAccess(sm,
1504 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
1505 }
1506 }
1507 return candidate;
1508 }
1509
1510 private native Class<?> getDeclaringClass0();
1511
1512
1513 /**
1514 * Returns the immediately enclosing class of the underlying
1515 * class. If the underlying class is a top level class this
1516 * method returns {@code null}.
1517 * @return the immediately enclosing class of the underlying class
1518 * @exception SecurityException
1519 * If a security manager, <i>s</i>, is present and the caller's
1520 * class loader is not the same as or an ancestor of the class
1521 * loader for the enclosing class and invocation of {@link
1522 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
1523 * denies access to the package of the enclosing class
1524 * @since 1.5
1525 */
1526 @CallerSensitive
1527 public Class<?> getEnclosingClass() throws SecurityException {
1528 // There are five kinds of classes (or interfaces):
1529 // a) Top level classes
1530 // b) Nested classes (static member classes)
1531 // c) Inner classes (non-static member classes)
1532 // d) Local classes (named classes declared within a method)
1533 // e) Anonymous classes
1534
1535
1536 // JVM Spec 4.7.7: A class must have an EnclosingMethod
1537 // attribute if and only if it is a local class or an
1538 // anonymous class.
1539 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1540 Class<?> enclosingCandidate;
1541
1542 if (enclosingInfo == null) {
1543 // This is a top level or a nested class or an inner class (a, b, or c)
1544 enclosingCandidate = getDeclaringClass0();
1545 } else {
1546 Class<?> enclosingClass = enclosingInfo.getEnclosingClass();
1547 // This is a local class or an anonymous class (d or e)
1548 if (enclosingClass == this || enclosingClass == null)
1549 throw new InternalError("Malformed enclosing method information");
1550 else
1551 enclosingCandidate = enclosingClass;
1552 }
1553
1554 if (enclosingCandidate != null) {
1555 SecurityManager sm = System.getSecurityManager();
1556 if (sm != null) {
1557 enclosingCandidate.checkPackageAccess(sm,
1558 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
1559 }
1560 }
1561 return enclosingCandidate;
1562 }
1563
1564 /**
1565 * Returns the simple name of the underlying class as given in the
1566 * source code. Returns an empty string if the underlying class is
1567 * anonymous.
1568 *
1569 * <p>The simple name of an array is the simple name of the
1570 * component type with "[]" appended. In particular the simple
1571 * name of an array whose component type is anonymous is "[]".
1572 *
1573 * @return the simple name of the underlying class
1574 * @since 1.5
1575 */
1576 public String getSimpleName() {
1577 ReflectionData<T> rd = reflectionData();
1578 String simpleName = rd.simpleName;
1579 if (simpleName == null) {
1580 rd.simpleName = simpleName = getSimpleName0();
1581 }
1582 return simpleName;
1583 }
1584
1585 private String getSimpleName0() {
1586 if (isArray()) {
1587 return getComponentType().getSimpleName() + "[]";
1588 }
1589 String simpleName = getSimpleBinaryName();
1590 if (simpleName == null) { // top level class
1591 simpleName = getName();
1592 simpleName = simpleName.substring(simpleName.lastIndexOf('.') + 1); // strip the package name
1593 }
1594 return simpleName;
1595 }
1596
1597 /**
1598 * Return an informative string for the name of this type.
1599 *
1600 * @return an informative string for the name of this type
1601 * @since 1.8
1602 */
1603 public String getTypeName() {
1604 if (isArray()) {
1605 try {
1606 Class<?> cl = this;
1607 int dimensions = 0;
1608 do {
1609 dimensions++;
1610 cl = cl.getComponentType();
1611 } while (cl.isArray());
1612 StringBuilder sb = new StringBuilder();
1613 sb.append(cl.getName());
1614 for (int i = 0; i < dimensions; i++) {
1615 sb.append("[]");
1616 }
1617 return sb.toString();
1618 } catch (Throwable e) { /*FALLTHRU*/ }
1619 }
1620 return getName();
1621 }
1622
1623 /**
1624 * Returns the canonical name of the underlying class as
1625 * defined by the Java Language Specification. Returns null if
1626 * the underlying class does not have a canonical name (i.e., if
1627 * it is a local or anonymous class or an array whose component
1628 * type does not have a canonical name).
1629 * @return the canonical name of the underlying class if it exists, and
1630 * {@code null} otherwise.
1631 * @since 1.5
1632 */
1633 public String getCanonicalName() {
1634 ReflectionData<T> rd = reflectionData();
1635 String canonicalName = rd.canonicalName;
1636 if (canonicalName == null) {
1637 rd.canonicalName = canonicalName = getCanonicalName0();
1638 }
1639 return canonicalName == ReflectionData.NULL_SENTINEL? null : canonicalName;
1640 }
1641
1642 private String getCanonicalName0() {
1643 if (isArray()) {
1644 String canonicalName = getComponentType().getCanonicalName();
1645 if (canonicalName != null)
1646 return canonicalName + "[]";
1647 else
1648 return ReflectionData.NULL_SENTINEL;
1649 }
1650 if (isLocalOrAnonymousClass())
1651 return ReflectionData.NULL_SENTINEL;
1652 Class<?> enclosingClass = getEnclosingClass();
1653 if (enclosingClass == null) { // top level class
1654 return getName();
1655 } else {
1656 String enclosingName = enclosingClass.getCanonicalName();
1657 if (enclosingName == null)
1658 return ReflectionData.NULL_SENTINEL;
1659 return enclosingName + "." + getSimpleName();
1660 }
1661 }
1662
1663 /**
1664 * Returns {@code true} if and only if the underlying class
1665 * is an anonymous class.
1666 *
1667 * @return {@code true} if and only if this class is an anonymous class.
1668 * @since 1.5
1669 */
1670 public boolean isAnonymousClass() {
1671 return !isArray() && isLocalOrAnonymousClass() &&
1672 getSimpleBinaryName0() == null;
1673 }
1674
1675 /**
1676 * Returns {@code true} if and only if the underlying class
1677 * is a local class.
1678 *
1679 * @return {@code true} if and only if this class is a local class.
1680 * @since 1.5
1681 */
1682 public boolean isLocalClass() {
1683 return isLocalOrAnonymousClass() &&
1684 (isArray() || getSimpleBinaryName0() != null);
1685 }
1686
1687 /**
1688 * Returns {@code true} if and only if the underlying class
1689 * is a member class.
1690 *
1691 * @return {@code true} if and only if this class is a member class.
1692 * @since 1.5
1693 */
1694 public boolean isMemberClass() {
1695 return !isLocalOrAnonymousClass() && getDeclaringClass0() != null;
1696 }
1697
1698 /**
1699 * Returns the "simple binary name" of the underlying class, i.e.,
1700 * the binary name without the leading enclosing class name.
1701 * Returns {@code null} if the underlying class is a top level
1702 * class.
1703 */
1704 private String getSimpleBinaryName() {
1705 if (isTopLevelClass())
1706 return null;
1707 String name = getSimpleBinaryName0();
1708 if (name == null) // anonymous class
1709 return "";
1710 return name;
1711 }
1712
1713 private native String getSimpleBinaryName0();
1714
1715 /**
1716 * Returns {@code true} if this is a top level class. Returns {@code false}
1717 * otherwise.
1718 */
1719 private boolean isTopLevelClass() {
1720 return !isLocalOrAnonymousClass() && getDeclaringClass0() == null;
1721 }
1722
1723 /**
1724 * Returns {@code true} if this is a local class or an anonymous
1725 * class. Returns {@code false} otherwise.
1726 */
1727 private boolean isLocalOrAnonymousClass() {
1728 // JVM Spec 4.7.7: A class must have an EnclosingMethod
1729 // attribute if and only if it is a local class or an
1730 // anonymous class.
1731 return hasEnclosingMethodInfo();
1732 }
1733
1734 private boolean hasEnclosingMethodInfo() {
1735 Object[] enclosingInfo = getEnclosingMethod0();
1736 if (enclosingInfo != null) {
1737 EnclosingMethodInfo.validate(enclosingInfo);
1738 return true;
1739 }
1740 return false;
1741 }
1742
1743 /**
1744 * Returns an array containing {@code Class} objects representing all
1745 * the public classes and interfaces that are members of the class
1746 * represented by this {@code Class} object. This includes public
1747 * class and interface members inherited from superclasses and public class
1748 * and interface members declared by the class. This method returns an
1749 * array of length 0 if this {@code Class} object has no public member
1750 * classes or interfaces. This method also returns an array of length 0 if
1751 * this {@code Class} object represents a primitive type, an array
1752 * class, or void.
1753 *
1754 * @return the array of {@code Class} objects representing the public
1755 * members of this class
1756 * @throws SecurityException
1757 * If a security manager, <i>s</i>, is present and
1758 * the caller's class loader is not the same as or an
1759 * ancestor of the class loader for the current class and
1760 * invocation of {@link SecurityManager#checkPackageAccess
1761 * s.checkPackageAccess()} denies access to the package
1762 * of this class.
1763 *
1764 * @since 1.1
1765 */
1766 @CallerSensitive
1767 public Class<?>[] getClasses() {
1768 SecurityManager sm = System.getSecurityManager();
1769 if (sm != null) {
1770 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), false);
1771 }
1772
1773 // Privileged so this implementation can look at DECLARED classes,
1774 // something the caller might not have privilege to do. The code here
1775 // is allowed to look at DECLARED classes because (1) it does not hand
1776 // out anything other than public members and (2) public member access
1777 // has already been ok'd by the SecurityManager.
1778
1779 return java.security.AccessController.doPrivileged(
1780 new java.security.PrivilegedAction<>() {
1781 public Class<?>[] run() {
1782 List<Class<?>> list = new ArrayList<>();
1783 Class<?> currentClass = Class.this;
1784 while (currentClass != null) {
1785 for (Class<?> m : currentClass.getDeclaredClasses()) {
1786 if (Modifier.isPublic(m.getModifiers())) {
1787 list.add(m);
1788 }
1789 }
1790 currentClass = currentClass.getSuperclass();
1791 }
1792 return list.toArray(new Class<?>[0]);
1793 }
1794 });
1795 }
1796
1797
1798 /**
1799 * Returns an array containing {@code Field} objects reflecting all
1800 * the accessible public fields of the class or interface represented by
1801 * this {@code Class} object.
1802 *
1803 * <p> If this {@code Class} object represents a class or interface with
1804 * no accessible public fields, then this method returns an array of length
1805 * 0.
1806 *
1807 * <p> If this {@code Class} object represents a class, then this method
1808 * returns the public fields of the class and of all its superclasses and
1809 * superinterfaces.
1810 *
1811 * <p> If this {@code Class} object represents an interface, then this
1812 * method returns the fields of the interface and of all its
1813 * superinterfaces.
1814 *
1815 * <p> If this {@code Class} object represents an array type, a primitive
1816 * type, or void, then this method returns an array of length 0.
1817 *
1818 * <p> The elements in the returned array are not sorted and are not in any
1819 * particular order.
1820 *
1821 * @return the array of {@code Field} objects representing the
1822 * public fields
1823 * @throws SecurityException
1824 * If a security manager, <i>s</i>, is present and
1825 * the caller's class loader is not the same as or an
1826 * ancestor of the class loader for the current class and
1827 * invocation of {@link SecurityManager#checkPackageAccess
1828 * s.checkPackageAccess()} denies access to the package
1829 * of this class.
1830 *
1831 * @since 1.1
1832 * @jls 8.2 Class Members
1833 * @jls 8.3 Field Declarations
1834 */
1835 @CallerSensitive
1836 public Field[] getFields() throws SecurityException {
1837 SecurityManager sm = System.getSecurityManager();
1838 if (sm != null) {
1839 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
1840 }
1841 return copyFields(privateGetPublicFields());
1842 }
1843
1844
1845 /**
1846 * Returns an array containing {@code Method} objects reflecting all the
1847 * public methods of the class or interface represented by this {@code
1848 * Class} object, including those declared by the class or interface and
1849 * those inherited from superclasses and superinterfaces.
1850 *
1851 * <p> If this {@code Class} object represents an array type, then the
1852 * returned array has a {@code Method} object for each of the public
1853 * methods inherited by the array type from {@code Object}. It does not
1854 * contain a {@code Method} object for {@code clone()}.
1855 *
1856 * <p> If this {@code Class} object represents an interface then the
1857 * returned array does not contain any implicitly declared methods from
1858 * {@code Object}. Therefore, if no methods are explicitly declared in
1859 * this interface or any of its superinterfaces then the returned array
1860 * has length 0. (Note that a {@code Class} object which represents a class
1861 * always has public methods, inherited from {@code Object}.)
1862 *
1863 * <p> The returned array never contains methods with names "{@code <init>}"
1864 * or "{@code <clinit>}".
1865 *
1866 * <p> The elements in the returned array are not sorted and are not in any
1867 * particular order.
1868 *
1869 * <p> Generally, the result is computed as with the following 4 step algorithm.
1870 * Let C be the class or interface represented by this {@code Class} object:
1871 * <ol>
1872 * <li> A union of methods is composed of:
1873 * <ol type="a">
1874 * <li> C's declared public instance and static methods as returned by
1875 * {@link #getDeclaredMethods()} and filtered to include only public
1876 * methods.</li>
1877 * <li> If C is a class other than {@code Object}, then include the result
1878 * of invoking this algorithm recursively on the superclass of C.</li>
1879 * <li> Include the results of invoking this algorithm recursively on all
1880 * direct superinterfaces of C, but include only instance methods.</li>
1881 * </ol></li>
1882 * <li> Union from step 1 is partitioned into subsets of methods with same
1883 * signature (name, parameter types) and return type.</li>
1884 * <li> Within each such subset only the most specific methods are selected.
1885 * Let method M be a method from a set of methods with same signature
1886 * and return type. M is most specific if there is no such method
1887 * N != M from the same set, such that N is more specific than M.
1888 * N is more specific than M if:
1889 * <ol type="a">
1890 * <li> N is declared by a class and M is declared by an interface; or</li>
1891 * <li> N and M are both declared by classes or both by interfaces and
1892 * N's declaring type is the same as or a subtype of M's declaring type
1893 * (clearly, if M's and N's declaring types are the same type, then
1894 * M and N are the same method).</li>
1895 * </ol></li>
1896 * <li> The result of this algorithm is the union of all selected methods from
1897 * step 3.</li>
1898 * </ol>
1899 *
1900 * @apiNote There may be more than one method with a particular name
1901 * and parameter types in a class because while the Java language forbids a
1902 * class to declare multiple methods with the same signature but different
1903 * return types, the Java virtual machine does not. This
1904 * increased flexibility in the virtual machine can be used to
1905 * implement various language features. For example, covariant
1906 * returns can be implemented with {@linkplain
1907 * java.lang.reflect.Method#isBridge bridge methods}; the bridge
1908 * method and the overriding method would have the same
1909 * signature but different return types.
1910 *
1911 * @return the array of {@code Method} objects representing the
1912 * public methods of this class
1913 * @throws SecurityException
1914 * If a security manager, <i>s</i>, is present and
1915 * the caller's class loader is not the same as or an
1916 * ancestor of the class loader for the current class and
1917 * invocation of {@link SecurityManager#checkPackageAccess
1918 * s.checkPackageAccess()} denies access to the package
1919 * of this class.
1920 *
1921 * @jls 8.2 Class Members
1922 * @jls 8.4 Method Declarations
1923 * @since 1.1
1924 */
1925 @CallerSensitive
1926 public Method[] getMethods() throws SecurityException {
1927 SecurityManager sm = System.getSecurityManager();
1928 if (sm != null) {
1929 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
1930 }
1931 return copyMethods(privateGetPublicMethods());
1932 }
1933
1934
1935 /**
1936 * Returns an array containing {@code Constructor} objects reflecting
1937 * all the public constructors of the class represented by this
1938 * {@code Class} object. An array of length 0 is returned if the
1939 * class has no public constructors, or if the class is an array class, or
1940 * if the class reflects a primitive type or void.
1941 *
1942 * Note that while this method returns an array of {@code
1943 * Constructor<T>} objects (that is an array of constructors from
1944 * this class), the return type of this method is {@code
1945 * Constructor<?>[]} and <em>not</em> {@code Constructor<T>[]} as
1946 * might be expected. This less informative return type is
1947 * necessary since after being returned from this method, the
1948 * array could be modified to hold {@code Constructor} objects for
1949 * different classes, which would violate the type guarantees of
1950 * {@code Constructor<T>[]}.
1951 *
1952 * @return the array of {@code Constructor} objects representing the
1953 * public constructors of this class
1954 * @throws SecurityException
1955 * If a security manager, <i>s</i>, is present and
1956 * the caller's class loader is not the same as or an
1957 * ancestor of the class loader for the current class and
1958 * invocation of {@link SecurityManager#checkPackageAccess
1959 * s.checkPackageAccess()} denies access to the package
1960 * of this class.
1961 *
1962 * @since 1.1
1963 */
1964 @CallerSensitive
1965 public Constructor<?>[] getConstructors() throws SecurityException {
1966 SecurityManager sm = System.getSecurityManager();
1967 if (sm != null) {
1968 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
1969 }
1970 return copyConstructors(privateGetDeclaredConstructors(true));
1971 }
1972
1973
1974 /**
1975 * Returns a {@code Field} object that reflects the specified public member
1976 * field of the class or interface represented by this {@code Class}
1977 * object. The {@code name} parameter is a {@code String} specifying the
1978 * simple name of the desired field.
1979 *
1980 * <p> The field to be reflected is determined by the algorithm that
1981 * follows. Let C be the class or interface represented by this object:
1982 *
1983 * <OL>
1984 * <LI> If C declares a public field with the name specified, that is the
1985 * field to be reflected.</LI>
1986 * <LI> If no field was found in step 1 above, this algorithm is applied
1987 * recursively to each direct superinterface of C. The direct
1988 * superinterfaces are searched in the order they were declared.</LI>
1989 * <LI> If no field was found in steps 1 and 2 above, and C has a
1990 * superclass S, then this algorithm is invoked recursively upon S.
1991 * If C has no superclass, then a {@code NoSuchFieldException}
1992 * is thrown.</LI>
1993 * </OL>
1994 *
1995 * <p> If this {@code Class} object represents an array type, then this
1996 * method does not find the {@code length} field of the array type.
1997 *
1998 * @param name the field name
1999 * @return the {@code Field} object of this class specified by
2000 * {@code name}
2001 * @throws NoSuchFieldException if a field with the specified name is
2002 * not found.
2003 * @throws NullPointerException if {@code name} is {@code null}
2004 * @throws SecurityException
2005 * If a security manager, <i>s</i>, is present and
2006 * the caller's class loader is not the same as or an
2007 * ancestor of the class loader for the current class and
2008 * invocation of {@link SecurityManager#checkPackageAccess
2009 * s.checkPackageAccess()} denies access to the package
2010 * of this class.
2011 *
2012 * @since 1.1
2013 * @jls 8.2 Class Members
2014 * @jls 8.3 Field Declarations
2015 */
2016 @CallerSensitive
2017 public Field getField(String name)
2018 throws NoSuchFieldException, SecurityException {
2019 Objects.requireNonNull(name);
2020 SecurityManager sm = System.getSecurityManager();
2021 if (sm != null) {
2022 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2023 }
2024 Field field = getField0(name);
2025 if (field == null) {
2026 throw new NoSuchFieldException(name);
2027 }
2028 return getReflectionFactory().copyField(field);
2029 }
2030
2031
2032 /**
2033 * Returns a {@code Method} object that reflects the specified public
2034 * member method of the class or interface represented by this
2035 * {@code Class} object. The {@code name} parameter is a
2036 * {@code String} specifying the simple name of the desired method. The
2037 * {@code parameterTypes} parameter is an array of {@code Class}
2038 * objects that identify the method's formal parameter types, in declared
2039 * order. If {@code parameterTypes} is {@code null}, it is
2040 * treated as if it were an empty array.
2041 *
2042 * <p> If this {@code Class} object represents an array type, then this
2043 * method finds any public method inherited by the array type from
2044 * {@code Object} except method {@code clone()}.
2045 *
2046 * <p> If this {@code Class} object represents an interface then this
2047 * method does not find any implicitly declared method from
2048 * {@code Object}. Therefore, if no methods are explicitly declared in
2049 * this interface or any of its superinterfaces, then this method does not
2050 * find any method.
2051 *
2052 * <p> This method does not find any method with name "{@code <init>}" or
2053 * "{@code <clinit>}".
2054 *
2055 * <p> Generally, the method to be reflected is determined by the 4 step
2056 * algorithm that follows.
2057 * Let C be the class or interface represented by this {@code Class} object:
2058 * <ol>
2059 * <li> A union of methods is composed of:
2060 * <ol type="a">
2061 * <li> C's declared public instance and static methods as returned by
2062 * {@link #getDeclaredMethods()} and filtered to include only public
2063 * methods that match given {@code name} and {@code parameterTypes}</li>
2064 * <li> If C is a class other than {@code Object}, then include the result
2065 * of invoking this algorithm recursively on the superclass of C.</li>
2066 * <li> Include the results of invoking this algorithm recursively on all
2067 * direct superinterfaces of C, but include only instance methods.</li>
2068 * </ol></li>
2069 * <li> This union is partitioned into subsets of methods with same
2070 * return type (the selection of methods from step 1 also guarantees that
2071 * they have the same method name and parameter types).</li>
2072 * <li> Within each such subset only the most specific methods are selected.
2073 * Let method M be a method from a set of methods with same VM
2074 * signature (return type, name, parameter types).
2075 * M is most specific if there is no such method N != M from the same
2076 * set, such that N is more specific than M. N is more specific than M
2077 * if:
2078 * <ol type="a">
2079 * <li> N is declared by a class and M is declared by an interface; or</li>
2080 * <li> N and M are both declared by classes or both by interfaces and
2081 * N's declaring type is the same as or a subtype of M's declaring type
2082 * (clearly, if M's and N's declaring types are the same type, then
2083 * M and N are the same method).</li>
2084 * </ol></li>
2085 * <li> The result of this algorithm is chosen arbitrarily from the methods
2086 * with most specific return type among all selected methods from step 3.
2087 * Let R be a return type of a method M from the set of all selected methods
2088 * from step 3. M is a method with most specific return type if there is
2089 * no such method N != M from the same set, having return type S != R,
2090 * such that S is a subtype of R as determined by
2091 * R.class.{@link #isAssignableFrom}(S.class).
2092 * </ol>
2093 *
2094 * @apiNote There may be more than one method with matching name and
2095 * parameter types in a class because while the Java language forbids a
2096 * class to declare multiple methods with the same signature but different
2097 * return types, the Java virtual machine does not. This
2098 * increased flexibility in the virtual machine can be used to
2099 * implement various language features. For example, covariant
2100 * returns can be implemented with {@linkplain
2101 * java.lang.reflect.Method#isBridge bridge methods}; the bridge
2102 * method and the overriding method would have the same
2103 * signature but different return types. This method would return the
2104 * overriding method as it would have a more specific return type.
2105 *
2106 * @param name the name of the method
2107 * @param parameterTypes the list of parameters
2108 * @return the {@code Method} object that matches the specified
2109 * {@code name} and {@code parameterTypes}
2110 * @throws NoSuchMethodException if a matching method is not found
2111 * or if the name is "<init>"or "<clinit>".
2112 * @throws NullPointerException if {@code name} is {@code null}
2113 * @throws SecurityException
2114 * If a security manager, <i>s</i>, is present and
2115 * the caller's class loader is not the same as or an
2116 * ancestor of the class loader for the current class and
2117 * invocation of {@link SecurityManager#checkPackageAccess
2118 * s.checkPackageAccess()} denies access to the package
2119 * of this class.
2120 *
2121 * @jls 8.2 Class Members
2122 * @jls 8.4 Method Declarations
2123 * @since 1.1
2124 */
2125 @CallerSensitive
2126 public Method getMethod(String name, Class<?>... parameterTypes)
2127 throws NoSuchMethodException, SecurityException {
2128 Objects.requireNonNull(name);
2129 SecurityManager sm = System.getSecurityManager();
2130 if (sm != null) {
2131 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2132 }
2133 Method method = getMethod0(name, parameterTypes);
2134 if (method == null) {
2135 throw new NoSuchMethodException(methodToString(name, parameterTypes));
2136 }
2137 return getReflectionFactory().copyMethod(method);
2138 }
2139
2140 /**
2141 * Returns a {@code Constructor} object that reflects the specified
2142 * public constructor of the class represented by this {@code Class}
2143 * object. The {@code parameterTypes} parameter is an array of
2144 * {@code Class} objects that identify the constructor's formal
2145 * parameter types, in declared order.
2146 *
2147 * If this {@code Class} object represents an inner class
2148 * declared in a non-static context, the formal parameter types
2149 * include the explicit enclosing instance as the first parameter.
2150 *
2151 * <p> The constructor to reflect is the public constructor of the class
2152 * represented by this {@code Class} object whose formal parameter
2153 * types match those specified by {@code parameterTypes}.
2154 *
2155 * @param parameterTypes the parameter array
2156 * @return the {@code Constructor} object of the public constructor that
2157 * matches the specified {@code parameterTypes}
2158 * @throws NoSuchMethodException if a matching method is not found.
2159 * @throws SecurityException
2160 * If a security manager, <i>s</i>, is present and
2161 * the caller's class loader is not the same as or an
2162 * ancestor of the class loader for the current class and
2163 * invocation of {@link SecurityManager#checkPackageAccess
2164 * s.checkPackageAccess()} denies access to the package
2165 * of this class.
2166 *
2167 * @since 1.1
2168 */
2169 @CallerSensitive
2170 public Constructor<T> getConstructor(Class<?>... parameterTypes)
2171 throws NoSuchMethodException, SecurityException
2172 {
2173 SecurityManager sm = System.getSecurityManager();
2174 if (sm != null) {
2175 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2176 }
2177 return getReflectionFactory().copyConstructor(
2178 getConstructor0(parameterTypes, Member.PUBLIC));
2179 }
2180
2181
2182 /**
2183 * Returns an array of {@code Class} objects reflecting all the
2184 * classes and interfaces declared as members of the class represented by
2185 * this {@code Class} object. This includes public, protected, default
2186 * (package) access, and private classes and interfaces declared by the
2187 * class, but excludes inherited classes and interfaces. This method
2188 * returns an array of length 0 if the class declares no classes or
2189 * interfaces as members, or if this {@code Class} object represents a
2190 * primitive type, an array class, or void.
2191 *
2192 * @return the array of {@code Class} objects representing all the
2193 * declared members of this class
2194 * @throws SecurityException
2195 * If a security manager, <i>s</i>, is present and any of the
2196 * following conditions is met:
2197 *
2198 * <ul>
2199 *
2200 * <li> the caller's class loader is not the same as the
2201 * class loader of this class and invocation of
2202 * {@link SecurityManager#checkPermission
2203 * s.checkPermission} method with
2204 * {@code RuntimePermission("accessDeclaredMembers")}
2205 * denies access to the declared classes within this class
2206 *
2207 * <li> the caller's class loader is not the same as or an
2208 * ancestor of the class loader for the current class and
2209 * invocation of {@link SecurityManager#checkPackageAccess
2210 * s.checkPackageAccess()} denies access to the package
2211 * of this class
2212 *
2213 * </ul>
2214 *
2215 * @since 1.1
2216 */
2217 @CallerSensitive
2218 public Class<?>[] getDeclaredClasses() throws SecurityException {
2219 SecurityManager sm = System.getSecurityManager();
2220 if (sm != null) {
2221 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), false);
2222 }
2223 return getDeclaredClasses0();
2224 }
2225
2226
2227 /**
2228 * Returns an array of {@code Field} objects reflecting all the fields
2229 * declared by the class or interface represented by this
2230 * {@code Class} object. This includes public, protected, default
2231 * (package) access, and private fields, but excludes inherited fields.
2232 *
2233 * <p> If this {@code Class} object represents a class or interface with no
2234 * declared fields, then this method returns an array of length 0.
2235 *
2236 * <p> If this {@code Class} object represents an array type, a primitive
2237 * type, or void, then this method returns an array of length 0.
2238 *
2239 * <p> The elements in the returned array are not sorted and are not in any
2240 * particular order.
2241 *
2242 * @return the array of {@code Field} objects representing all the
2243 * declared fields of this class
2244 * @throws SecurityException
2245 * If a security manager, <i>s</i>, is present and any of the
2246 * following conditions is met:
2247 *
2248 * <ul>
2249 *
2250 * <li> the caller's class loader is not the same as the
2251 * class loader of this class and invocation of
2252 * {@link SecurityManager#checkPermission
2253 * s.checkPermission} method with
2254 * {@code RuntimePermission("accessDeclaredMembers")}
2255 * denies access to the declared fields within this class
2256 *
2257 * <li> the caller's class loader is not the same as or an
2258 * ancestor of the class loader for the current class and
2259 * invocation of {@link SecurityManager#checkPackageAccess
2260 * s.checkPackageAccess()} denies access to the package
2261 * of this class
2262 *
2263 * </ul>
2264 *
2265 * @since 1.1
2266 * @jls 8.2 Class Members
2267 * @jls 8.3 Field Declarations
2268 */
2269 @CallerSensitive
2270 public Field[] getDeclaredFields() throws SecurityException {
2271 SecurityManager sm = System.getSecurityManager();
2272 if (sm != null) {
2273 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2274 }
2275 return copyFields(privateGetDeclaredFields(false));
2276 }
2277
2278
2279 /**
2280 * Returns an array containing {@code Method} objects reflecting all the
2281 * declared methods of the class or interface represented by this {@code
2282 * Class} object, including public, protected, default (package)
2283 * access, and private methods, but excluding inherited methods.
2284 *
2285 * <p> If this {@code Class} object represents a type that has multiple
2286 * declared methods with the same name and parameter types, but different
2287 * return types, then the returned array has a {@code Method} object for
2288 * each such method.
2289 *
2290 * <p> If this {@code Class} object represents a type that has a class
2291 * initialization method {@code <clinit>}, then the returned array does
2292 * <em>not</em> have a corresponding {@code Method} object.
2293 *
2294 * <p> If this {@code Class} object represents a class or interface with no
2295 * declared methods, then the returned array has length 0.
2296 *
2297 * <p> If this {@code Class} object represents an array type, a primitive
2298 * type, or void, then the returned array has length 0.
2299 *
2300 * <p> The elements in the returned array are not sorted and are not in any
2301 * particular order.
2302 *
2303 * @return the array of {@code Method} objects representing all the
2304 * declared methods of this class
2305 * @throws SecurityException
2306 * If a security manager, <i>s</i>, is present and any of the
2307 * following conditions is met:
2308 *
2309 * <ul>
2310 *
2311 * <li> the caller's class loader is not the same as the
2312 * class loader of this class and invocation of
2313 * {@link SecurityManager#checkPermission
2314 * s.checkPermission} method with
2315 * {@code RuntimePermission("accessDeclaredMembers")}
2316 * denies access to the declared methods within this class
2317 *
2318 * <li> the caller's class loader is not the same as or an
2319 * ancestor of the class loader for the current class and
2320 * invocation of {@link SecurityManager#checkPackageAccess
2321 * s.checkPackageAccess()} denies access to the package
2322 * of this class
2323 *
2324 * </ul>
2325 *
2326 * @jls 8.2 Class Members
2327 * @jls 8.4 Method Declarations
2328 * @since 1.1
2329 */
2330 @CallerSensitive
2331 public Method[] getDeclaredMethods() throws SecurityException {
2332 SecurityManager sm = System.getSecurityManager();
2333 if (sm != null) {
2334 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2335 }
2336 return copyMethods(privateGetDeclaredMethods(false));
2337 }
2338
2339
2340 /**
2341 * Returns an array of {@code Constructor} objects reflecting all the
2342 * constructors declared by the class represented by this
2343 * {@code Class} object. These are public, protected, default
2344 * (package) access, and private constructors. The elements in the array
2345 * returned are not sorted and are not in any particular order. If the
2346 * class has a default constructor, it is included in the returned array.
2347 * This method returns an array of length 0 if this {@code Class}
2348 * object represents an interface, a primitive type, an array class, or
2349 * void.
2350 *
2351 * <p> See <em>The Java Language Specification</em>, section 8.2.
2352 *
2353 * @return the array of {@code Constructor} objects representing all the
2354 * declared constructors of this class
2355 * @throws SecurityException
2356 * If a security manager, <i>s</i>, is present and any of the
2357 * following conditions is met:
2358 *
2359 * <ul>
2360 *
2361 * <li> the caller's class loader is not the same as the
2362 * class loader of this class and invocation of
2363 * {@link SecurityManager#checkPermission
2364 * s.checkPermission} method with
2365 * {@code RuntimePermission("accessDeclaredMembers")}
2366 * denies access to the declared constructors within this class
2367 *
2368 * <li> the caller's class loader is not the same as or an
2369 * ancestor of the class loader for the current class and
2370 * invocation of {@link SecurityManager#checkPackageAccess
2371 * s.checkPackageAccess()} denies access to the package
2372 * of this class
2373 *
2374 * </ul>
2375 *
2376 * @since 1.1
2377 */
2378 @CallerSensitive
2379 public Constructor<?>[] getDeclaredConstructors() throws SecurityException {
2380 SecurityManager sm = System.getSecurityManager();
2381 if (sm != null) {
2382 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2383 }
2384 return copyConstructors(privateGetDeclaredConstructors(false));
2385 }
2386
2387
2388 /**
2389 * Returns a {@code Field} object that reflects the specified declared
2390 * field of the class or interface represented by this {@code Class}
2391 * object. The {@code name} parameter is a {@code String} that specifies
2392 * the simple name of the desired field.
2393 *
2394 * <p> If this {@code Class} object represents an array type, then this
2395 * method does not find the {@code length} field of the array type.
2396 *
2397 * @param name the name of the field
2398 * @return the {@code Field} object for the specified field in this
2399 * class
2400 * @throws NoSuchFieldException if a field with the specified name is
2401 * not found.
2402 * @throws NullPointerException if {@code name} is {@code null}
2403 * @throws SecurityException
2404 * If a security manager, <i>s</i>, is present and any of the
2405 * following conditions is met:
2406 *
2407 * <ul>
2408 *
2409 * <li> the caller's class loader is not the same as the
2410 * class loader of this class and invocation of
2411 * {@link SecurityManager#checkPermission
2412 * s.checkPermission} method with
2413 * {@code RuntimePermission("accessDeclaredMembers")}
2414 * denies access to the declared field
2415 *
2416 * <li> the caller's class loader is not the same as or an
2417 * ancestor of the class loader for the current class and
2418 * invocation of {@link SecurityManager#checkPackageAccess
2419 * s.checkPackageAccess()} denies access to the package
2420 * of this class
2421 *
2422 * </ul>
2423 *
2424 * @since 1.1
2425 * @jls 8.2 Class Members
2426 * @jls 8.3 Field Declarations
2427 */
2428 @CallerSensitive
2429 public Field getDeclaredField(String name)
2430 throws NoSuchFieldException, SecurityException {
2431 Objects.requireNonNull(name);
2432 SecurityManager sm = System.getSecurityManager();
2433 if (sm != null) {
2434 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2435 }
2436 Field field = searchFields(privateGetDeclaredFields(false), name);
2437 if (field == null) {
2438 throw new NoSuchFieldException(name);
2439 }
2440 return getReflectionFactory().copyField(field);
2441 }
2442
2443
2444 /**
2445 * Returns a {@code Method} object that reflects the specified
2446 * declared method of the class or interface represented by this
2447 * {@code Class} object. The {@code name} parameter is a
2448 * {@code String} that specifies the simple name of the desired
2449 * method, and the {@code parameterTypes} parameter is an array of
2450 * {@code Class} objects that identify the method's formal parameter
2451 * types, in declared order. If more than one method with the same
2452 * parameter types is declared in a class, and one of these methods has a
2453 * return type that is more specific than any of the others, that method is
2454 * returned; otherwise one of the methods is chosen arbitrarily. If the
2455 * name is "<init>"or "<clinit>" a {@code NoSuchMethodException}
2456 * is raised.
2457 *
2458 * <p> If this {@code Class} object represents an array type, then this
2459 * method does not find the {@code clone()} method.
2460 *
2461 * @param name the name of the method
2462 * @param parameterTypes the parameter array
2463 * @return the {@code Method} object for the method of this class
2464 * matching the specified name and parameters
2465 * @throws NoSuchMethodException if a matching method is not found.
2466 * @throws NullPointerException if {@code name} is {@code null}
2467 * @throws SecurityException
2468 * If a security manager, <i>s</i>, is present and any of the
2469 * following conditions is met:
2470 *
2471 * <ul>
2472 *
2473 * <li> the caller's class loader is not the same as the
2474 * class loader of this class and invocation of
2475 * {@link SecurityManager#checkPermission
2476 * s.checkPermission} method with
2477 * {@code RuntimePermission("accessDeclaredMembers")}
2478 * denies access to the declared method
2479 *
2480 * <li> the caller's class loader is not the same as or an
2481 * ancestor of the class loader for the current class and
2482 * invocation of {@link SecurityManager#checkPackageAccess
2483 * s.checkPackageAccess()} denies access to the package
2484 * of this class
2485 *
2486 * </ul>
2487 *
2488 * @jls 8.2 Class Members
2489 * @jls 8.4 Method Declarations
2490 * @since 1.1
2491 */
2492 @CallerSensitive
2493 public Method getDeclaredMethod(String name, Class<?>... parameterTypes)
2494 throws NoSuchMethodException, SecurityException {
2495 Objects.requireNonNull(name);
2496 SecurityManager sm = System.getSecurityManager();
2497 if (sm != null) {
2498 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2499 }
2500 Method method = searchMethods(privateGetDeclaredMethods(false), name, parameterTypes);
2501 if (method == null) {
2502 throw new NoSuchMethodException(methodToString(name, parameterTypes));
2503 }
2504 return getReflectionFactory().copyMethod(method);
2505 }
2506
2507 /**
2508 * Returns the list of {@code Method} objects for the declared public
2509 * methods of this class or interface that have the specified method name
2510 * and parameter types.
2511 *
2512 * @param name the name of the method
2513 * @param parameterTypes the parameter array
2514 * @return the list of {@code Method} objects for the public methods of
2515 * this class matching the specified name and parameters
2516 */
2517 List<Method> getDeclaredPublicMethods(String name, Class<?>... parameterTypes) {
2518 Method[] methods = privateGetDeclaredMethods(/* publicOnly */ true);
2519 ReflectionFactory factory = getReflectionFactory();
2520 List<Method> result = new ArrayList<>();
2521 for (Method method : methods) {
2522 if (method.getName().equals(name)
2523 && Arrays.equals(
2524 factory.getExecutableSharedParameterTypes(method),
2525 parameterTypes)) {
2526 result.add(factory.copyMethod(method));
2527 }
2528 }
2529 return result;
2530 }
2531
2532 /**
2533 * Returns a {@code Constructor} object that reflects the specified
2534 * constructor of the class or interface represented by this
2535 * {@code Class} object. The {@code parameterTypes} parameter is
2536 * an array of {@code Class} objects that identify the constructor's
2537 * formal parameter types, in declared order.
2538 *
2539 * If this {@code Class} object represents an inner class
2540 * declared in a non-static context, the formal parameter types
2541 * include the explicit enclosing instance as the first parameter.
2542 *
2543 * @param parameterTypes the parameter array
2544 * @return The {@code Constructor} object for the constructor with the
2545 * specified parameter list
2546 * @throws NoSuchMethodException if a matching method is not found.
2547 * @throws SecurityException
2548 * If a security manager, <i>s</i>, is present and any of the
2549 * following conditions is met:
2550 *
2551 * <ul>
2552 *
2553 * <li> the caller's class loader is not the same as the
2554 * class loader of this class and invocation of
2555 * {@link SecurityManager#checkPermission
2556 * s.checkPermission} method with
2557 * {@code RuntimePermission("accessDeclaredMembers")}
2558 * denies access to the declared constructor
2559 *
2560 * <li> the caller's class loader is not the same as or an
2561 * ancestor of the class loader for the current class and
2562 * invocation of {@link SecurityManager#checkPackageAccess
2563 * s.checkPackageAccess()} denies access to the package
2564 * of this class
2565 *
2566 * </ul>
2567 *
2568 * @since 1.1
2569 */
2570 @CallerSensitive
2571 public Constructor<T> getDeclaredConstructor(Class<?>... parameterTypes)
2572 throws NoSuchMethodException, SecurityException
2573 {
2574 SecurityManager sm = System.getSecurityManager();
2575 if (sm != null) {
2576 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2577 }
2578
2579 return getReflectionFactory().copyConstructor(
2580 getConstructor0(parameterTypes, Member.DECLARED));
2581 }
2582
2583 /**
2584 * Finds a resource with a given name.
2585 *
2586 * <p> If this class is in a named {@link Module Module} then this method
2587 * will attempt to find the resource in the module. This is done by
2588 * delegating to the module's class loader {@link
2589 * ClassLoader#findResource(String,String) findResource(String,String)}
2590 * method, invoking it with the module name and the absolute name of the
2591 * resource. Resources in named modules are subject to the rules for
2592 * encapsulation specified in the {@code Module} {@link
2593 * Module#getResourceAsStream getResourceAsStream} method and so this
2594 * method returns {@code null} when the resource is a
2595 * non-"{@code .class}" resource in a package that is not open to the
2596 * caller's module.
2597 *
2598 * <p> Otherwise, if this class is not in a named module then the rules for
2599 * searching resources associated with a given class are implemented by the
2600 * defining {@linkplain ClassLoader class loader} of the class. This method
2601 * delegates to this object's class loader. If this object was loaded by
2602 * the bootstrap class loader, the method delegates to {@link
2603 * ClassLoader#getSystemResourceAsStream}.
2604 *
2605 * <p> Before delegation, an absolute resource name is constructed from the
2606 * given resource name using this algorithm:
2607 *
2608 * <ul>
2609 *
2610 * <li> If the {@code name} begins with a {@code '/'}
2611 * (<code>'\u002f'</code>), then the absolute name of the resource is the
2612 * portion of the {@code name} following the {@code '/'}.
2613 *
2614 * <li> Otherwise, the absolute name is of the following form:
2615 *
2616 * <blockquote>
2617 * {@code modified_package_name/name}
2618 * </blockquote>
2619 *
2620 * <p> Where the {@code modified_package_name} is the package name of this
2621 * object with {@code '/'} substituted for {@code '.'}
2622 * (<code>'\u002e'</code>).
2623 *
2624 * </ul>
2625 *
2626 * @param name name of the desired resource
2627 * @return A {@link java.io.InputStream} object; {@code null} if no
2628 * resource with this name is found, the resource is in a package
2629 * that is not {@linkplain Module#isOpen(String, Module) open} to at
2630 * least the caller module, or access to the resource is denied
2631 * by the security manager.
2632 * @throws NullPointerException If {@code name} is {@code null}
2633 *
2634 * @see Module#getResourceAsStream(String)
2635 * @since 1.1
2636 * @revised 9
2637 * @spec JPMS
2638 */
2639 @CallerSensitive
2640 public InputStream getResourceAsStream(String name) {
2641 name = resolveName(name);
2642
2643 Module thisModule = getModule();
2644 if (thisModule.isNamed()) {
2645 // check if resource can be located by caller
2646 if (Resources.canEncapsulate(name)
2647 && !isOpenToCaller(name, Reflection.getCallerClass())) {
2648 return null;
2649 }
2650
2651 // resource not encapsulated or in package open to caller
2652 String mn = thisModule.getName();
2653 ClassLoader cl = getClassLoader0();
2654 try {
2655
2656 // special-case built-in class loaders to avoid the
2657 // need for a URL connection
2658 if (cl == null) {
2659 return BootLoader.findResourceAsStream(mn, name);
2660 } else if (cl instanceof BuiltinClassLoader) {
2661 return ((BuiltinClassLoader) cl).findResourceAsStream(mn, name);
2662 } else {
2663 URL url = cl.findResource(mn, name);
2664 return (url != null) ? url.openStream() : null;
2665 }
2666
2667 } catch (IOException | SecurityException e) {
2668 return null;
2669 }
2670 }
2671
2672 // unnamed module
2673 ClassLoader cl = getClassLoader0();
2674 if (cl == null) {
2675 return ClassLoader.getSystemResourceAsStream(name);
2676 } else {
2677 return cl.getResourceAsStream(name);
2678 }
2679 }
2680
2681 /**
2682 * Finds a resource with a given name.
2683 *
2684 * <p> If this class is in a named {@link Module Module} then this method
2685 * will attempt to find the resource in the module. This is done by
2686 * delegating to the module's class loader {@link
2687 * ClassLoader#findResource(String,String) findResource(String,String)}
2688 * method, invoking it with the module name and the absolute name of the
2689 * resource. Resources in named modules are subject to the rules for
2690 * encapsulation specified in the {@code Module} {@link
2691 * Module#getResourceAsStream getResourceAsStream} method and so this
2692 * method returns {@code null} when the resource is a
2693 * non-"{@code .class}" resource in a package that is not open to the
2694 * caller's module.
2695 *
2696 * <p> Otherwise, if this class is not in a named module then the rules for
2697 * searching resources associated with a given class are implemented by the
2698 * defining {@linkplain ClassLoader class loader} of the class. This method
2699 * delegates to this object's class loader. If this object was loaded by
2700 * the bootstrap class loader, the method delegates to {@link
2701 * ClassLoader#getSystemResource}.
2702 *
2703 * <p> Before delegation, an absolute resource name is constructed from the
2704 * given resource name using this algorithm:
2705 *
2706 * <ul>
2707 *
2708 * <li> If the {@code name} begins with a {@code '/'}
2709 * (<code>'\u002f'</code>), then the absolute name of the resource is the
2710 * portion of the {@code name} following the {@code '/'}.
2711 *
2712 * <li> Otherwise, the absolute name is of the following form:
2713 *
2714 * <blockquote>
2715 * {@code modified_package_name/name}
2716 * </blockquote>
2717 *
2718 * <p> Where the {@code modified_package_name} is the package name of this
2719 * object with {@code '/'} substituted for {@code '.'}
2720 * (<code>'\u002e'</code>).
2721 *
2722 * </ul>
2723 *
2724 * @param name name of the desired resource
2725 * @return A {@link java.net.URL} object; {@code null} if no resource with
2726 * this name is found, the resource cannot be located by a URL, the
2727 * resource is in a package that is not
2728 * {@linkplain Module#isOpen(String, Module) open} to at least the caller
2729 * module, or access to the resource is denied by the security
2730 * manager.
2731 * @throws NullPointerException If {@code name} is {@code null}
2732 * @since 1.1
2733 * @revised 9
2734 * @spec JPMS
2735 */
2736 @CallerSensitive
2737 public URL getResource(String name) {
2738 name = resolveName(name);
2739
2740 Module thisModule = getModule();
2741 if (thisModule.isNamed()) {
2742 // check if resource can be located by caller
2743 if (Resources.canEncapsulate(name)
2744 && !isOpenToCaller(name, Reflection.getCallerClass())) {
2745 return null;
2746 }
2747
2748 // resource not encapsulated or in package open to caller
2749 String mn = thisModule.getName();
2750 ClassLoader cl = getClassLoader0();
2751 try {
2752 if (cl == null) {
2753 return BootLoader.findResource(mn, name);
2754 } else {
2755 return cl.findResource(mn, name);
2756 }
2757 } catch (IOException ioe) {
2758 return null;
2759 }
2760 }
2761
2762 // unnamed module
2763 ClassLoader cl = getClassLoader0();
2764 if (cl == null) {
2765 return ClassLoader.getSystemResource(name);
2766 } else {
2767 return cl.getResource(name);
2768 }
2769 }
2770
2771 /**
2772 * Returns true if a resource with the given name can be located by the
2773 * given caller. All resources in a module can be located by code in
2774 * the module. For other callers, then the package needs to be open to
2775 * the caller.
2776 */
2777 private boolean isOpenToCaller(String name, Class<?> caller) {
2778 // assert getModule().isNamed();
2779 Module thisModule = getModule();
2780 Module callerModule = (caller != null) ? caller.getModule() : null;
2781 if (callerModule != thisModule) {
2782 String pn = Resources.toPackageName(name);
2783 if (thisModule.getDescriptor().packages().contains(pn)) {
2784 if (callerModule == null && !thisModule.isOpen(pn)) {
2785 // no caller, package not open
2786 return false;
2787 }
2788 if (!thisModule.isOpen(pn, callerModule)) {
2789 // package not open to caller
2790 return false;
2791 }
2792 }
2793 }
2794 return true;
2795 }
2796
2797
2798 /** protection domain returned when the internal domain is null */
2799 private static java.security.ProtectionDomain allPermDomain;
2800
2801 /**
2802 * Returns the {@code ProtectionDomain} of this class. If there is a
2803 * security manager installed, this method first calls the security
2804 * manager's {@code checkPermission} method with a
2805 * {@code RuntimePermission("getProtectionDomain")} permission to
2806 * ensure it's ok to get the
2807 * {@code ProtectionDomain}.
2808 *
2809 * @return the ProtectionDomain of this class
2810 *
2811 * @throws SecurityException
2812 * if a security manager exists and its
2813 * {@code checkPermission} method doesn't allow
2814 * getting the ProtectionDomain.
2815 *
2816 * @see java.security.ProtectionDomain
2817 * @see SecurityManager#checkPermission
2818 * @see java.lang.RuntimePermission
2819 * @since 1.2
2820 */
2821 public java.security.ProtectionDomain getProtectionDomain() {
2822 SecurityManager sm = System.getSecurityManager();
2823 if (sm != null) {
2824 sm.checkPermission(SecurityConstants.GET_PD_PERMISSION);
2825 }
2826 java.security.ProtectionDomain pd = getProtectionDomain0();
2827 if (pd == null) {
2828 if (allPermDomain == null) {
2829 java.security.Permissions perms =
2830 new java.security.Permissions();
2831 perms.add(SecurityConstants.ALL_PERMISSION);
2832 allPermDomain =
2833 new java.security.ProtectionDomain(null, perms);
2834 }
2835 pd = allPermDomain;
2836 }
2837 return pd;
2838 }
2839
2840
2841 /**
2842 * Returns the ProtectionDomain of this class.
2843 */
2844 private native java.security.ProtectionDomain getProtectionDomain0();
2845
2846 /*
2847 * Return the Virtual Machine's Class object for the named
2848 * primitive type.
2849 */
2850 static native Class<?> getPrimitiveClass(String name);
2851
2852 /*
2853 * Check if client is allowed to access members. If access is denied,
2854 * throw a SecurityException.
2855 *
2856 * This method also enforces package access.
2857 *
2858 * <p> Default policy: allow all clients access with normal Java access
2859 * control.
2860 *
2861 * <p> NOTE: should only be called if a SecurityManager is installed
2862 */
2863 private void checkMemberAccess(SecurityManager sm, int which,
2864 Class<?> caller, boolean checkProxyInterfaces) {
2865 /* Default policy allows access to all {@link Member#PUBLIC} members,
2866 * as well as access to classes that have the same class loader as the caller.
2867 * In all other cases, it requires RuntimePermission("accessDeclaredMembers")
2868 * permission.
2869 */
2870 final ClassLoader ccl = ClassLoader.getClassLoader(caller);
2871 if (which != Member.PUBLIC) {
2872 final ClassLoader cl = getClassLoader0();
2873 if (ccl != cl) {
2874 sm.checkPermission(SecurityConstants.CHECK_MEMBER_ACCESS_PERMISSION);
2875 }
2876 }
2877 this.checkPackageAccess(sm, ccl, checkProxyInterfaces);
2878 }
2879
2880 /*
2881 * Checks if a client loaded in ClassLoader ccl is allowed to access this
2882 * class under the current package access policy. If access is denied,
2883 * throw a SecurityException.
2884 *
2885 * NOTE: this method should only be called if a SecurityManager is active
2886 */
2887 private void checkPackageAccess(SecurityManager sm, final ClassLoader ccl,
2888 boolean checkProxyInterfaces) {
2889 final ClassLoader cl = getClassLoader0();
2890
2891 if (ReflectUtil.needsPackageAccessCheck(ccl, cl)) {
2892 String pkg = this.getPackageName();
2893 if (pkg != null && !pkg.isEmpty()) {
2894 // skip the package access check on a proxy class in default proxy package
2895 if (!Proxy.isProxyClass(this) || ReflectUtil.isNonPublicProxyClass(this)) {
2896 sm.checkPackageAccess(pkg);
2897 }
2898 }
2899 }
2900 // check package access on the proxy interfaces
2901 if (checkProxyInterfaces && Proxy.isProxyClass(this)) {
2902 ReflectUtil.checkProxyPackageAccess(ccl, this.getInterfaces());
2903 }
2904 }
2905
2906 /**
2907 * Add a package name prefix if the name is not absolute Remove leading "/"
2908 * if name is absolute
2909 */
2910 private String resolveName(String name) {
2911 if (!name.startsWith("/")) {
2912 Class<?> c = this;
2913 while (c.isArray()) {
2914 c = c.getComponentType();
2915 }
2916 String baseName = c.getPackageName();
2917 if (baseName != null && !baseName.isEmpty()) {
2918 name = baseName.replace('.', '/') + "/" + name;
2919 }
2920 } else {
2921 name = name.substring(1);
2922 }
2923 return name;
2924 }
2925
2926 /**
2927 * Atomic operations support.
2928 */
2929 private static class Atomic {
2930 // initialize Unsafe machinery here, since we need to call Class.class instance method
2931 // and have to avoid calling it in the static initializer of the Class class...
2932 private static final Unsafe unsafe = Unsafe.getUnsafe();
2933 // offset of Class.reflectionData instance field
2934 private static final long reflectionDataOffset
2935 = unsafe.objectFieldOffset(Class.class, "reflectionData");
2936 // offset of Class.annotationType instance field
2937 private static final long annotationTypeOffset
2938 = unsafe.objectFieldOffset(Class.class, "annotationType");
2939 // offset of Class.annotationData instance field
2940 private static final long annotationDataOffset
2941 = unsafe.objectFieldOffset(Class.class, "annotationData");
2942
2943 static <T> boolean casReflectionData(Class<?> clazz,
2944 SoftReference<ReflectionData<T>> oldData,
2945 SoftReference<ReflectionData<T>> newData) {
2946 return unsafe.compareAndSetObject(clazz, reflectionDataOffset, oldData, newData);
2947 }
2948
2949 static <T> boolean casAnnotationType(Class<?> clazz,
2950 AnnotationType oldType,
2951 AnnotationType newType) {
2952 return unsafe.compareAndSetObject(clazz, annotationTypeOffset, oldType, newType);
2953 }
2954
2955 static <T> boolean casAnnotationData(Class<?> clazz,
2956 AnnotationData oldData,
2957 AnnotationData newData) {
2958 return unsafe.compareAndSetObject(clazz, annotationDataOffset, oldData, newData);
2959 }
2960 }
2961
2962 /**
2963 * Reflection support.
2964 */
2965
2966 // Reflection data caches various derived names and reflective members. Cached
2967 // values may be invalidated when JVM TI RedefineClasses() is called
2968 private static class ReflectionData<T> {
2969 volatile Field[] declaredFields;
2970 volatile Field[] publicFields;
2971 volatile Method[] declaredMethods;
2972 volatile Method[] publicMethods;
2973 volatile Constructor<T>[] declaredConstructors;
2974 volatile Constructor<T>[] publicConstructors;
2975 // Intermediate results for getFields and getMethods
2976 volatile Field[] declaredPublicFields;
2977 volatile Method[] declaredPublicMethods;
2978 volatile Class<?>[] interfaces;
2979
2980 // Cached names
2981 String simpleName;
2982 String canonicalName;
2983 static final String NULL_SENTINEL = new String();
2984
2985 // Value of classRedefinedCount when we created this ReflectionData instance
2986 final int redefinedCount;
2987
2988 ReflectionData(int redefinedCount) {
2989 this.redefinedCount = redefinedCount;
2990 }
2991 }
2992
2993 private transient volatile SoftReference<ReflectionData<T>> reflectionData;
2994
2995 // Incremented by the VM on each call to JVM TI RedefineClasses()
2996 // that redefines this class or a superclass.
2997 private transient volatile int classRedefinedCount;
2998
2999 // Lazily create and cache ReflectionData
3000 private ReflectionData<T> reflectionData() {
3001 SoftReference<ReflectionData<T>> reflectionData = this.reflectionData;
3002 int classRedefinedCount = this.classRedefinedCount;
3003 ReflectionData<T> rd;
3004 if (reflectionData != null &&
3005 (rd = reflectionData.get()) != null &&
3006 rd.redefinedCount == classRedefinedCount) {
3007 return rd;
3008 }
3009 // else no SoftReference or cleared SoftReference or stale ReflectionData
3010 // -> create and replace new instance
3011 return newReflectionData(reflectionData, classRedefinedCount);
3012 }
3013
3014 private ReflectionData<T> newReflectionData(SoftReference<ReflectionData<T>> oldReflectionData,
3015 int classRedefinedCount) {
3016 while (true) {
3017 ReflectionData<T> rd = new ReflectionData<>(classRedefinedCount);
3018 // try to CAS it...
3019 if (Atomic.casReflectionData(this, oldReflectionData, new SoftReference<>(rd))) {
3020 return rd;
3021 }
3022 // else retry
3023 oldReflectionData = this.reflectionData;
3024 classRedefinedCount = this.classRedefinedCount;
3025 if (oldReflectionData != null &&
3026 (rd = oldReflectionData.get()) != null &&
3027 rd.redefinedCount == classRedefinedCount) {
3028 return rd;
3029 }
3030 }
3031 }
3032
3033 // Generic signature handling
3034 private native String getGenericSignature0();
3035
3036 // Generic info repository; lazily initialized
3037 private transient volatile ClassRepository genericInfo;
3038
3039 // accessor for factory
3040 private GenericsFactory getFactory() {
3041 // create scope and factory
3042 return CoreReflectionFactory.make(this, ClassScope.make(this));
3043 }
3044
3045 // accessor for generic info repository;
3046 // generic info is lazily initialized
3047 private ClassRepository getGenericInfo() {
3048 ClassRepository genericInfo = this.genericInfo;
3049 if (genericInfo == null) {
3050 String signature = getGenericSignature0();
3051 if (signature == null) {
3052 genericInfo = ClassRepository.NONE;
3053 } else {
3054 genericInfo = ClassRepository.make(signature, getFactory());
3055 }
3056 this.genericInfo = genericInfo;
3057 }
3058 return (genericInfo != ClassRepository.NONE) ? genericInfo : null;
3059 }
3060
3061 // Annotations handling
3062 native byte[] getRawAnnotations();
3063 // Since 1.8
3064 native byte[] getRawTypeAnnotations();
3065 static byte[] getExecutableTypeAnnotationBytes(Executable ex) {
3066 return getReflectionFactory().getExecutableTypeAnnotationBytes(ex);
3067 }
3068
3069 native ConstantPool getConstantPool();
3070
3071 //
3072 //
3073 // java.lang.reflect.Field handling
3074 //
3075 //
3076
3077 // Returns an array of "root" fields. These Field objects must NOT
3078 // be propagated to the outside world, but must instead be copied
3079 // via ReflectionFactory.copyField.
3080 private Field[] privateGetDeclaredFields(boolean publicOnly) {
3081 Field[] res;
3082 ReflectionData<T> rd = reflectionData();
3083 if (rd != null) {
3084 res = publicOnly ? rd.declaredPublicFields : rd.declaredFields;
3085 if (res != null) return res;
3086 }
3087 // No cached value available; request value from VM
3088 res = Reflection.filterFields(this, getDeclaredFields0(publicOnly));
3089 if (rd != null) {
3090 if (publicOnly) {
3091 rd.declaredPublicFields = res;
3092 } else {
3093 rd.declaredFields = res;
3094 }
3095 }
3096 return res;
3097 }
3098
3099 // Returns an array of "root" fields. These Field objects must NOT
3100 // be propagated to the outside world, but must instead be copied
3101 // via ReflectionFactory.copyField.
3102 private Field[] privateGetPublicFields() {
3103 Field[] res;
3104 ReflectionData<T> rd = reflectionData();
3105 if (rd != null) {
3106 res = rd.publicFields;
3107 if (res != null) return res;
3108 }
3109
3110 // Use a linked hash set to ensure order is preserved and
3111 // fields from common super interfaces are not duplicated
3112 LinkedHashSet<Field> fields = new LinkedHashSet<>();
3113
3114 // Local fields
3115 addAll(fields, privateGetDeclaredFields(true));
3116
3117 // Direct superinterfaces, recursively
3118 for (Class<?> si : getInterfaces()) {
3119 addAll(fields, si.privateGetPublicFields());
3120 }
3121
3122 // Direct superclass, recursively
3123 Class<?> sc = getSuperclass();
3124 if (sc != null) {
3125 addAll(fields, sc.privateGetPublicFields());
3126 }
3127
3128 res = fields.toArray(new Field[0]);
3129 if (rd != null) {
3130 rd.publicFields = res;
3131 }
3132 return res;
3133 }
3134
3135 private static void addAll(Collection<Field> c, Field[] o) {
3136 for (Field f : o) {
3137 c.add(f);
3138 }
3139 }
3140
3141
3142 //
3143 //
3144 // java.lang.reflect.Constructor handling
3145 //
3146 //
3147
3148 // Returns an array of "root" constructors. These Constructor
3149 // objects must NOT be propagated to the outside world, but must
3150 // instead be copied via ReflectionFactory.copyConstructor.
3151 private Constructor<T>[] privateGetDeclaredConstructors(boolean publicOnly) {
3152 Constructor<T>[] res;
3153 ReflectionData<T> rd = reflectionData();
3154 if (rd != null) {
3155 res = publicOnly ? rd.publicConstructors : rd.declaredConstructors;
3156 if (res != null) return res;
3157 }
3158 // No cached value available; request value from VM
3159 if (isInterface()) {
3160 @SuppressWarnings("unchecked")
3161 Constructor<T>[] temporaryRes = (Constructor<T>[]) new Constructor<?>[0];
3162 res = temporaryRes;
3163 } else {
3164 res = getDeclaredConstructors0(publicOnly);
3165 }
3166 if (rd != null) {
3167 if (publicOnly) {
3168 rd.publicConstructors = res;
3169 } else {
3170 rd.declaredConstructors = res;
3171 }
3172 }
3173 return res;
3174 }
3175
3176 //
3177 //
3178 // java.lang.reflect.Method handling
3179 //
3180 //
3181
3182 // Returns an array of "root" methods. These Method objects must NOT
3183 // be propagated to the outside world, but must instead be copied
3184 // via ReflectionFactory.copyMethod.
3185 private Method[] privateGetDeclaredMethods(boolean publicOnly) {
3186 Method[] res;
3187 ReflectionData<T> rd = reflectionData();
3188 if (rd != null) {
3189 res = publicOnly ? rd.declaredPublicMethods : rd.declaredMethods;
3190 if (res != null) return res;
3191 }
3192 // No cached value available; request value from VM
3193 res = Reflection.filterMethods(this, getDeclaredMethods0(publicOnly));
3194 if (rd != null) {
3195 if (publicOnly) {
3196 rd.declaredPublicMethods = res;
3197 } else {
3198 rd.declaredMethods = res;
3199 }
3200 }
3201 return res;
3202 }
3203
3204 // Returns an array of "root" methods. These Method objects must NOT
3205 // be propagated to the outside world, but must instead be copied
3206 // via ReflectionFactory.copyMethod.
3207 private Method[] privateGetPublicMethods() {
3208 Method[] res;
3209 ReflectionData<T> rd = reflectionData();
3210 if (rd != null) {
3211 res = rd.publicMethods;
3212 if (res != null) return res;
3213 }
3214
3215 // No cached value available; compute value recursively.
3216 // Start by fetching public declared methods...
3217 PublicMethods pms = new PublicMethods();
3218 for (Method m : privateGetDeclaredMethods(/* publicOnly */ true)) {
3219 pms.merge(m);
3220 }
3221 // ...then recur over superclass methods...
3222 Class<?> sc = getSuperclass();
3223 if (sc != null) {
3224 for (Method m : sc.privateGetPublicMethods()) {
3225 pms.merge(m);
3226 }
3227 }
3228 // ...and finally over direct superinterfaces.
3229 for (Class<?> intf : getInterfaces(/* cloneArray */ false)) {
3230 for (Method m : intf.privateGetPublicMethods()) {
3231 // static interface methods are not inherited
3232 if (!Modifier.isStatic(m.getModifiers())) {
3233 pms.merge(m);
3234 }
3235 }
3236 }
3237
3238 res = pms.toArray();
3239 if (rd != null) {
3240 rd.publicMethods = res;
3241 }
3242 return res;
3243 }
3244
3245
3246 //
3247 // Helpers for fetchers of one field, method, or constructor
3248 //
3249
3250 // This method does not copy the returned Field object!
3251 private static Field searchFields(Field[] fields, String name) {
3252 for (Field field : fields) {
3253 if (field.getName().equals(name)) {
3254 return field;
3255 }
3256 }
3257 return null;
3258 }
3259
3260 // Returns a "root" Field object. This Field object must NOT
3261 // be propagated to the outside world, but must instead be copied
3262 // via ReflectionFactory.copyField.
3263 private Field getField0(String name) {
3264 // Note: the intent is that the search algorithm this routine
3265 // uses be equivalent to the ordering imposed by
3266 // privateGetPublicFields(). It fetches only the declared
3267 // public fields for each class, however, to reduce the number
3268 // of Field objects which have to be created for the common
3269 // case where the field being requested is declared in the
3270 // class which is being queried.
3271 Field res;
3272 // Search declared public fields
3273 if ((res = searchFields(privateGetDeclaredFields(true), name)) != null) {
3274 return res;
3275 }
3276 // Direct superinterfaces, recursively
3277 Class<?>[] interfaces = getInterfaces(/* cloneArray */ false);
3278 for (Class<?> c : interfaces) {
3279 if ((res = c.getField0(name)) != null) {
3280 return res;
3281 }
3282 }
3283 // Direct superclass, recursively
3284 if (!isInterface()) {
3285 Class<?> c = getSuperclass();
3286 if (c != null) {
3287 if ((res = c.getField0(name)) != null) {
3288 return res;
3289 }
3290 }
3291 }
3292 return null;
3293 }
3294
3295 // This method does not copy the returned Method object!
3296 private static Method searchMethods(Method[] methods,
3297 String name,
3298 Class<?>[] parameterTypes)
3299 {
3300 ReflectionFactory fact = getReflectionFactory();
3301 Method res = null;
3302 for (Method m : methods) {
3303 if (m.getName().equals(name)
3304 && arrayContentsEq(parameterTypes,
3305 fact.getExecutableSharedParameterTypes(m))
3306 && (res == null
3307 || (res.getReturnType() != m.getReturnType()
3308 && res.getReturnType().isAssignableFrom(m.getReturnType()))))
3309 res = m;
3310 }
3311 return res;
3312 }
3313
3314 private static final Class<?>[] EMPTY_CLASS_ARRAY = new Class<?>[0];
3315
3316 // Returns a "root" Method object. This Method object must NOT
3317 // be propagated to the outside world, but must instead be copied
3318 // via ReflectionFactory.copyMethod.
3319 private Method getMethod0(String name, Class<?>[] parameterTypes) {
3320 PublicMethods.MethodList res = getMethodsRecursive(
3321 name,
3322 parameterTypes == null ? EMPTY_CLASS_ARRAY : parameterTypes,
3323 /* includeStatic */ true);
3324 return res == null ? null : res.getMostSpecific();
3325 }
3326
3327 // Returns a list of "root" Method objects. These Method objects must NOT
3328 // be propagated to the outside world, but must instead be copied
3329 // via ReflectionFactory.copyMethod.
3330 private PublicMethods.MethodList getMethodsRecursive(String name,
3331 Class<?>[] parameterTypes,
3332 boolean includeStatic) {
3333 // 1st check declared public methods
3334 Method[] methods = privateGetDeclaredMethods(/* publicOnly */ true);
3335 PublicMethods.MethodList res = PublicMethods.MethodList
3336 .filter(methods, name, parameterTypes, includeStatic);
3337 // if there is at least one match among declared methods, we need not
3338 // search any further as such match surely overrides matching methods
3339 // declared in superclass(es) or interface(s).
3340 if (res != null) {
3341 return res;
3342 }
3343
3344 // if there was no match among declared methods,
3345 // we must consult the superclass (if any) recursively...
3346 Class<?> sc = getSuperclass();
3347 if (sc != null) {
3348 res = sc.getMethodsRecursive(name, parameterTypes, includeStatic);
3349 }
3350
3351 // ...and coalesce the superclass methods with methods obtained
3352 // from directly implemented interfaces excluding static methods...
3353 for (Class<?> intf : getInterfaces(/* cloneArray */ false)) {
3354 res = PublicMethods.MethodList.merge(
3355 res, intf.getMethodsRecursive(name, parameterTypes,
3356 /* includeStatic */ false));
3357 }
3358
3359 return res;
3360 }
3361
3362 // Returns a "root" Constructor object. This Constructor object must NOT
3363 // be propagated to the outside world, but must instead be copied
3364 // via ReflectionFactory.copyConstructor.
3365 private Constructor<T> getConstructor0(Class<?>[] parameterTypes,
3366 int which) throws NoSuchMethodException
3367 {
3368 ReflectionFactory fact = getReflectionFactory();
3369 Constructor<T>[] constructors = privateGetDeclaredConstructors((which == Member.PUBLIC));
3370 for (Constructor<T> constructor : constructors) {
3371 if (arrayContentsEq(parameterTypes,
3372 fact.getExecutableSharedParameterTypes(constructor))) {
3373 return constructor;
3374 }
3375 }
3376 throw new NoSuchMethodException(methodToString("<init>", parameterTypes));
3377 }
3378
3379 //
3380 // Other helpers and base implementation
3381 //
3382
3383 private static boolean arrayContentsEq(Object[] a1, Object[] a2) {
3384 if (a1 == null) {
3385 return a2 == null || a2.length == 0;
3386 }
3387
3388 if (a2 == null) {
3389 return a1.length == 0;
3390 }
3391
3392 if (a1.length != a2.length) {
3393 return false;
3394 }
3395
3396 for (int i = 0; i < a1.length; i++) {
3397 if (a1[i] != a2[i]) {
3398 return false;
3399 }
3400 }
3401
3402 return true;
3403 }
3404
3405 private static Field[] copyFields(Field[] arg) {
3406 Field[] out = new Field[arg.length];
3407 ReflectionFactory fact = getReflectionFactory();
3408 for (int i = 0; i < arg.length; i++) {
3409 out[i] = fact.copyField(arg[i]);
3410 }
3411 return out;
3412 }
3413
3414 private static Method[] copyMethods(Method[] arg) {
3415 Method[] out = new Method[arg.length];
3416 ReflectionFactory fact = getReflectionFactory();
3417 for (int i = 0; i < arg.length; i++) {
3418 out[i] = fact.copyMethod(arg[i]);
3419 }
3420 return out;
3421 }
3422
3423 private static <U> Constructor<U>[] copyConstructors(Constructor<U>[] arg) {
3424 Constructor<U>[] out = arg.clone();
3425 ReflectionFactory fact = getReflectionFactory();
3426 for (int i = 0; i < out.length; i++) {
3427 out[i] = fact.copyConstructor(out[i]);
3428 }
3429 return out;
3430 }
3431
3432 private native Field[] getDeclaredFields0(boolean publicOnly);
3433 private native Method[] getDeclaredMethods0(boolean publicOnly);
3434 private native Constructor<T>[] getDeclaredConstructors0(boolean publicOnly);
3435 private native Class<?>[] getDeclaredClasses0();
3436
3437 /**
3438 * Helper method to get the method name from arguments.
3439 */
3440 private String methodToString(String name, Class<?>[] argTypes) {
3441 StringJoiner sj = new StringJoiner(", ", getName() + "." + name + "(", ")");
3442 if (argTypes != null) {
3443 for (int i = 0; i < argTypes.length; i++) {
3444 Class<?> c = argTypes[i];
3445 sj.add((c == null) ? "null" : c.getName());
3446 }
3447 }
3448 return sj.toString();
3449 }
3450
3451 /** use serialVersionUID from JDK 1.1 for interoperability */
3452 private static final long serialVersionUID = 3206093459760846163L;
3453
3454
3455 /**
3456 * Class Class is special cased within the Serialization Stream Protocol.
3457 *
3458 * A Class instance is written initially into an ObjectOutputStream in the
3459 * following format:
3460 * <pre>
3461 * {@code TC_CLASS} ClassDescriptor
3462 * A ClassDescriptor is a special cased serialization of
3463 * a {@code java.io.ObjectStreamClass} instance.
3464 * </pre>
3465 * A new handle is generated for the initial time the class descriptor
3466 * is written into the stream. Future references to the class descriptor
3467 * are written as references to the initial class descriptor instance.
3468 *
3469 * @see java.io.ObjectStreamClass
3470 */
3471 private static final ObjectStreamField[] serialPersistentFields =
3472 new ObjectStreamField[0];
3473
3474
3475 /**
3476 * Returns the assertion status that would be assigned to this
3477 * class if it were to be initialized at the time this method is invoked.
3478 * If this class has had its assertion status set, the most recent
3479 * setting will be returned; otherwise, if any package default assertion
3480 * status pertains to this class, the most recent setting for the most
3481 * specific pertinent package default assertion status is returned;
3482 * otherwise, if this class is not a system class (i.e., it has a
3483 * class loader) its class loader's default assertion status is returned;
3484 * otherwise, the system class default assertion status is returned.
3485 * <p>
3486 * Few programmers will have any need for this method; it is provided
3487 * for the benefit of the JRE itself. (It allows a class to determine at
3488 * the time that it is initialized whether assertions should be enabled.)
3489 * Note that this method is not guaranteed to return the actual
3490 * assertion status that was (or will be) associated with the specified
3491 * class when it was (or will be) initialized.
3492 *
3493 * @return the desired assertion status of the specified class.
3494 * @see java.lang.ClassLoader#setClassAssertionStatus
3495 * @see java.lang.ClassLoader#setPackageAssertionStatus
3496 * @see java.lang.ClassLoader#setDefaultAssertionStatus
3497 * @since 1.4
3498 */
3499 public boolean desiredAssertionStatus() {
3500 ClassLoader loader = getClassLoader0();
3501 // If the loader is null this is a system class, so ask the VM
3502 if (loader == null)
3503 return desiredAssertionStatus0(this);
3504
3505 // If the classloader has been initialized with the assertion
3506 // directives, ask it. Otherwise, ask the VM.
3507 synchronized(loader.assertionLock) {
3508 if (loader.classAssertionStatus != null) {
3509 return loader.desiredAssertionStatus(getName());
3510 }
3511 }
3512 return desiredAssertionStatus0(this);
3513 }
3514
3515 // Retrieves the desired assertion status of this class from the VM
3516 private static native boolean desiredAssertionStatus0(Class<?> clazz);
3517
3518 /**
3519 * Returns true if and only if this class was declared as an enum in the
3520 * source code.
3521 *
3522 * @return true if and only if this class was declared as an enum in the
3523 * source code
3524 * @since 1.5
3525 */
3526 public boolean isEnum() {
3527 // An enum must both directly extend java.lang.Enum and have
3528 // the ENUM bit set; classes for specialized enum constants
3529 // don't do the former.
3530 return (this.getModifiers() & ENUM) != 0 &&
3531 this.getSuperclass() == java.lang.Enum.class;
3532 }
3533
3534 // Fetches the factory for reflective objects
3535 private static ReflectionFactory getReflectionFactory() {
3536 if (reflectionFactory == null) {
3537 reflectionFactory =
3538 java.security.AccessController.doPrivileged
3539 (new ReflectionFactory.GetReflectionFactoryAction());
3540 }
3541 return reflectionFactory;
3542 }
3543 private static ReflectionFactory reflectionFactory;
3544
3545 /**
3546 * Returns the elements of this enum class or null if this
3547 * Class object does not represent an enum type.
3548 *
3549 * @return an array containing the values comprising the enum class
3550 * represented by this Class object in the order they're
3551 * declared, or null if this Class object does not
3552 * represent an enum type
3553 * @since 1.5
3554 */
3555 public T[] getEnumConstants() {
3556 T[] values = getEnumConstantsShared();
3557 return (values != null) ? values.clone() : null;
3558 }
3559
3560 /**
3561 * Returns the elements of this enum class or null if this
3562 * Class object does not represent an enum type;
3563 * identical to getEnumConstants except that the result is
3564 * uncloned, cached, and shared by all callers.
3565 */
3566 T[] getEnumConstantsShared() {
3567 T[] constants = enumConstants;
3568 if (constants == null) {
3569 if (!isEnum()) return null;
3570 try {
3571 final Method values = getMethod("values");
3572 java.security.AccessController.doPrivileged(
3573 new java.security.PrivilegedAction<>() {
3574 public Void run() {
3575 values.setAccessible(true);
3576 return null;
3577 }
3578 });
3579 @SuppressWarnings("unchecked")
3580 T[] temporaryConstants = (T[])values.invoke(null);
3581 enumConstants = constants = temporaryConstants;
3582 }
3583 // These can happen when users concoct enum-like classes
3584 // that don't comply with the enum spec.
3585 catch (InvocationTargetException | NoSuchMethodException |
3586 IllegalAccessException ex) { return null; }
3587 }
3588 return constants;
3589 }
3590 private transient volatile T[] enumConstants;
3591
3592 /**
3593 * Returns a map from simple name to enum constant. This package-private
3594 * method is used internally by Enum to implement
3595 * {@code public static <T extends Enum<T>> T valueOf(Class<T>, String)}
3596 * efficiently. Note that the map is returned by this method is
3597 * created lazily on first use. Typically it won't ever get created.
3598 */
3599 Map<String, T> enumConstantDirectory() {
3600 Map<String, T> directory = enumConstantDirectory;
3601 if (directory == null) {
3602 T[] universe = getEnumConstantsShared();
3603 if (universe == null)
3604 throw new IllegalArgumentException(
3605 getName() + " is not an enum type");
3606 directory = new HashMap<>((int)(universe.length / 0.75f) + 1);
3607 for (T constant : universe) {
3608 directory.put(((Enum<?>)constant).name(), constant);
3609 }
3610 enumConstantDirectory = directory;
3611 }
3612 return directory;
3613 }
3614 private transient volatile Map<String, T> enumConstantDirectory;
3615
3616 /**
3617 * Casts an object to the class or interface represented
3618 * by this {@code Class} object.
3619 *
3620 * @param obj the object to be cast
3621 * @return the object after casting, or null if obj is null
3622 *
3623 * @throws ClassCastException if the object is not
3624 * null and is not assignable to the type T.
3625 *
3626 * @since 1.5
3627 */
3628 @SuppressWarnings("unchecked")
3629 @HotSpotIntrinsicCandidate
3630 public T cast(Object obj) {
3631 if (obj != null && !isInstance(obj))
3632 throw new ClassCastException(cannotCastMsg(obj));
3633 return (T) obj;
3634 }
3635
3636 private String cannotCastMsg(Object obj) {
3637 return "Cannot cast " + obj.getClass().getName() + " to " + getName();
3638 }
3639
3640 /**
3641 * Casts this {@code Class} object to represent a subclass of the class
3642 * represented by the specified class object. Checks that the cast
3643 * is valid, and throws a {@code ClassCastException} if it is not. If
3644 * this method succeeds, it always returns a reference to this class object.
3645 *
3646 * <p>This method is useful when a client needs to "narrow" the type of
3647 * a {@code Class} object to pass it to an API that restricts the
3648 * {@code Class} objects that it is willing to accept. A cast would
3649 * generate a compile-time warning, as the correctness of the cast
3650 * could not be checked at runtime (because generic types are implemented
3651 * by erasure).
3652 *
3653 * @param <U> the type to cast this class object to
3654 * @param clazz the class of the type to cast this class object to
3655 * @return this {@code Class} object, cast to represent a subclass of
3656 * the specified class object.
3657 * @throws ClassCastException if this {@code Class} object does not
3658 * represent a subclass of the specified class (here "subclass" includes
3659 * the class itself).
3660 * @since 1.5
3661 */
3662 @SuppressWarnings("unchecked")
3663 public <U> Class<? extends U> asSubclass(Class<U> clazz) {
3664 if (clazz.isAssignableFrom(this))
3665 return (Class<? extends U>) this;
3666 else
3667 throw new ClassCastException(this.toString());
3668 }
3669
3670 /**
3671 * @throws NullPointerException {@inheritDoc}
3672 * @since 1.5
3673 */
3674 @SuppressWarnings("unchecked")
3675 public <A extends Annotation> A getAnnotation(Class<A> annotationClass) {
3676 Objects.requireNonNull(annotationClass);
3677
3678 return (A) annotationData().annotations.get(annotationClass);
3679 }
3680
3681 /**
3682 * {@inheritDoc}
3683 * @throws NullPointerException {@inheritDoc}
3684 * @since 1.5
3685 */
3686 @Override
3687 public boolean isAnnotationPresent(Class<? extends Annotation> annotationClass) {
3688 return GenericDeclaration.super.isAnnotationPresent(annotationClass);
3689 }
3690
3691 /**
3692 * @throws NullPointerException {@inheritDoc}
3693 * @since 1.8
3694 */
3695 @Override
3696 public <A extends Annotation> A[] getAnnotationsByType(Class<A> annotationClass) {
3697 Objects.requireNonNull(annotationClass);
3698
3699 AnnotationData annotationData = annotationData();
3700 return AnnotationSupport.getAssociatedAnnotations(annotationData.declaredAnnotations,
3701 this,
3702 annotationClass);
3703 }
3704
3705 /**
3706 * @since 1.5
3707 */
3708 public Annotation[] getAnnotations() {
3709 return AnnotationParser.toArray(annotationData().annotations);
3710 }
3711
3712 /**
3713 * @throws NullPointerException {@inheritDoc}
3714 * @since 1.8
3715 */
3716 @Override
3717 @SuppressWarnings("unchecked")
3718 public <A extends Annotation> A getDeclaredAnnotation(Class<A> annotationClass) {
3719 Objects.requireNonNull(annotationClass);
3720
3721 return (A) annotationData().declaredAnnotations.get(annotationClass);
3722 }
3723
3724 /**
3725 * @throws NullPointerException {@inheritDoc}
3726 * @since 1.8
3727 */
3728 @Override
3729 public <A extends Annotation> A[] getDeclaredAnnotationsByType(Class<A> annotationClass) {
3730 Objects.requireNonNull(annotationClass);
3731
3732 return AnnotationSupport.getDirectlyAndIndirectlyPresent(annotationData().declaredAnnotations,
3733 annotationClass);
3734 }
3735
3736 /**
3737 * @since 1.5
3738 */
3739 public Annotation[] getDeclaredAnnotations() {
3740 return AnnotationParser.toArray(annotationData().declaredAnnotations);
3741 }
3742
3743 // annotation data that might get invalidated when JVM TI RedefineClasses() is called
3744 private static class AnnotationData {
3745 final Map<Class<? extends Annotation>, Annotation> annotations;
3746 final Map<Class<? extends Annotation>, Annotation> declaredAnnotations;
3747
3748 // Value of classRedefinedCount when we created this AnnotationData instance
3749 final int redefinedCount;
3750
3751 AnnotationData(Map<Class<? extends Annotation>, Annotation> annotations,
3752 Map<Class<? extends Annotation>, Annotation> declaredAnnotations,
3753 int redefinedCount) {
3754 this.annotations = annotations;
3755 this.declaredAnnotations = declaredAnnotations;
3756 this.redefinedCount = redefinedCount;
3757 }
3758 }
3759
3760 // Annotations cache
3761 @SuppressWarnings("UnusedDeclaration")
3762 private transient volatile AnnotationData annotationData;
3763
3764 private AnnotationData annotationData() {
3765 while (true) { // retry loop
3766 AnnotationData annotationData = this.annotationData;
3767 int classRedefinedCount = this.classRedefinedCount;
3768 if (annotationData != null &&
3769 annotationData.redefinedCount == classRedefinedCount) {
3770 return annotationData;
3771 }
3772 // null or stale annotationData -> optimistically create new instance
3773 AnnotationData newAnnotationData = createAnnotationData(classRedefinedCount);
3774 // try to install it
3775 if (Atomic.casAnnotationData(this, annotationData, newAnnotationData)) {
3776 // successfully installed new AnnotationData
3777 return newAnnotationData;
3778 }
3779 }
3780 }
3781
3782 private AnnotationData createAnnotationData(int classRedefinedCount) {
3783 Map<Class<? extends Annotation>, Annotation> declaredAnnotations =
3784 AnnotationParser.parseAnnotations(getRawAnnotations(), getConstantPool(), this);
3785 Class<?> superClass = getSuperclass();
3786 Map<Class<? extends Annotation>, Annotation> annotations = null;
3787 if (superClass != null) {
3788 Map<Class<? extends Annotation>, Annotation> superAnnotations =
3789 superClass.annotationData().annotations;
3790 for (Map.Entry<Class<? extends Annotation>, Annotation> e : superAnnotations.entrySet()) {
3791 Class<? extends Annotation> annotationClass = e.getKey();
3792 if (AnnotationType.getInstance(annotationClass).isInherited()) {
3793 if (annotations == null) { // lazy construction
3794 annotations = new LinkedHashMap<>((Math.max(
3795 declaredAnnotations.size(),
3796 Math.min(12, declaredAnnotations.size() + superAnnotations.size())
3797 ) * 4 + 2) / 3
3798 );
3799 }
3800 annotations.put(annotationClass, e.getValue());
3801 }
3802 }
3803 }
3804 if (annotations == null) {
3805 // no inherited annotations -> share the Map with declaredAnnotations
3806 annotations = declaredAnnotations;
3807 } else {
3808 // at least one inherited annotation -> declared may override inherited
3809 annotations.putAll(declaredAnnotations);
3810 }
3811 return new AnnotationData(annotations, declaredAnnotations, classRedefinedCount);
3812 }
3813
3814 // Annotation types cache their internal (AnnotationType) form
3815
3816 @SuppressWarnings("UnusedDeclaration")
3817 private transient volatile AnnotationType annotationType;
3818
3819 boolean casAnnotationType(AnnotationType oldType, AnnotationType newType) {
3820 return Atomic.casAnnotationType(this, oldType, newType);
3821 }
3822
3823 AnnotationType getAnnotationType() {
3824 return annotationType;
3825 }
3826
3827 Map<Class<? extends Annotation>, Annotation> getDeclaredAnnotationMap() {
3828 return annotationData().declaredAnnotations;
3829 }
3830
3831 /* Backing store of user-defined values pertaining to this class.
3832 * Maintained by the ClassValue class.
3833 */
3834 transient ClassValue.ClassValueMap classValueMap;
3835
3836 /**
3837 * Returns an {@code AnnotatedType} object that represents the use of a
3838 * type to specify the superclass of the entity represented by this {@code
3839 * Class} object. (The <em>use</em> of type Foo to specify the superclass
3840 * in '... extends Foo' is distinct from the <em>declaration</em> of type
3841 * Foo.)
3842 *
3843 * <p> If this {@code Class} object represents a type whose declaration
3844 * does not explicitly indicate an annotated superclass, then the return
3845 * value is an {@code AnnotatedType} object representing an element with no
3846 * annotations.
3847 *
3848 * <p> If this {@code Class} represents either the {@code Object} class, an
3849 * interface type, an array type, a primitive type, or void, the return
3850 * value is {@code null}.
3851 *
3852 * @return an object representing the superclass
3853 * @since 1.8
3854 */
3855 public AnnotatedType getAnnotatedSuperclass() {
3856 if (this == Object.class ||
3857 isInterface() ||
3858 isArray() ||
3859 isPrimitive() ||
3860 this == Void.TYPE) {
3861 return null;
3862 }
3863
3864 return TypeAnnotationParser.buildAnnotatedSuperclass(getRawTypeAnnotations(), getConstantPool(), this);
3865 }
3866
3867 /**
3868 * Returns an array of {@code AnnotatedType} objects that represent the use
3869 * of types to specify superinterfaces of the entity represented by this
3870 * {@code Class} object. (The <em>use</em> of type Foo to specify a
3871 * superinterface in '... implements Foo' is distinct from the
3872 * <em>declaration</em> of type Foo.)
3873 *
3874 * <p> If this {@code Class} object represents a class, the return value is
3875 * an array containing objects representing the uses of interface types to
3876 * specify interfaces implemented by the class. The order of the objects in
3877 * the array corresponds to the order of the interface types used in the
3878 * 'implements' clause of the declaration of this {@code Class} object.
3879 *
3880 * <p> If this {@code Class} object represents an interface, the return
3881 * value is an array containing objects representing the uses of interface
3882 * types to specify interfaces directly extended by the interface. The
3883 * order of the objects in the array corresponds to the order of the
3884 * interface types used in the 'extends' clause of the declaration of this
3885 * {@code Class} object.
3886 *
3887 * <p> If this {@code Class} object represents a class or interface whose
3888 * declaration does not explicitly indicate any annotated superinterfaces,
3889 * the return value is an array of length 0.
3890 *
3891 * <p> If this {@code Class} object represents either the {@code Object}
3892 * class, an array type, a primitive type, or void, the return value is an
3893 * array of length 0.
3894 *
3895 * @return an array representing the superinterfaces
3896 * @since 1.8
3897 */
3898 public AnnotatedType[] getAnnotatedInterfaces() {
3899 return TypeAnnotationParser.buildAnnotatedInterfaces(getRawTypeAnnotations(), getConstantPool(), this);
3900 }
3901
3902 private native Class<?> getNestHost0();
3903
3904 /**
3905 * Returns the nest host of the <a href=#nest>nest</a> to which the class
3906 * or interface represented by this {@code Class} object belongs.
3907 * Every class and interface is a member of exactly one nest.
3908 * A class or interface that is not recorded as belonging to a nest
3909 * belongs to the nest consisting only of itself, and is the nest
3910 * host.
3911 *
3912 * <p>Each of the {@code Class} objects representing array types,
3913 * primitive types, and {@code void} returns {@code this} to indicate
3914 * that the represented entity belongs to the nest consisting only of
3915 * itself, and is the nest host.
3916 *
3917 * <p>If there is a {@linkplain LinkageError linkage error} accessing
3918 * the nest host, or if this class or interface is not enumerated as
3919 * a member of the nest by the nest host, then it is considered to belong
3920 * to its own nest and {@code this} is returned as the host.
3921 *
3922 * @apiNote A {@code class} file of version 55.0 or greater may record the
3923 * host of the nest to which it belongs by using the {@code NestHost}
3924 * attribute (JVMS 4.7.28). Alternatively, a {@code class} file of
3925 * version 55.0 or greater may act as a nest host by enumerating the nest's
3926 * other members with the
3927 * {@code NestMembers} attribute (JVMS 4.7.29).
3928 * A {@code class} file of version 54.0 or lower does not use these
3929 * attributes.
3930 *
3931 * @return the nest host of this class or interface
3932 *
3933 * @throws SecurityException
3934 * If the returned class is not the current class, and
3935 * if a security manager, <i>s</i>, is present and the caller's
3936 * class loader is not the same as or an ancestor of the class
3937 * loader for the returned class and invocation of {@link
3938 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
3939 * denies access to the package of the returned class
3940 * @since 11
3941 * @jvms 4.7.28 and 4.7.29 NestHost and NestMembers attributes
3942 * @jvms 5.4.4 Access Control
3943 */
3944 @CallerSensitive
3945 public Class<?> getNestHost() {
3946 if (isPrimitive() || isArray()) {
3947 return this;
3948 }
3949 Class<?> host;
3950 try {
3951 host = getNestHost0();
3952 } catch (LinkageError e) {
3953 // if we couldn't load our nest-host then we
3954 // act as-if we have no nest-host attribute
3955 return this;
3956 }
3957 // if null then nest membership validation failed, so we
3958 // act as-if we have no nest-host attribute
3959 if (host == null || host == this) {
3960 return this;
3961 }
3962 // returning a different class requires a security check
3963 SecurityManager sm = System.getSecurityManager();
3964 if (sm != null) {
3965 checkPackageAccess(sm,
3966 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
3967 }
3968 return host;
3969 }
3970
3971 /**
3972 * Determines if the given {@code Class} is a nestmate of the
3973 * class or interface represented by this {@code Class} object.
3974 * Two classes or interfaces are nestmates
3975 * if they have the same {@linkplain #getNestHost() nest host}.
3976 *
3977 * @param c the class to check
3978 * @return {@code true} if this class and {@code c} are members of
3979 * the same nest; and {@code false} otherwise.
3980 *
3981 * @since 11
3982 */
3983 public boolean isNestmateOf(Class<?> c) {
3984 if (this == c) {
3985 return true;
3986 }
3987 if (isPrimitive() || isArray() ||
3988 c.isPrimitive() || c.isArray()) {
3989 return false;
3990 }
3991 try {
3992 return getNestHost0() == c.getNestHost0();
3993 } catch (LinkageError e) {
3994 return false;
3995 }
3996 }
3997
3998 private native Class<?>[] getNestMembers0();
3999
4000 /**
4001 * Returns an array containing {@code Class} objects representing all the
4002 * classes and interfaces that are members of the nest to which the class
4003 * or interface represented by this {@code Class} object belongs.
4004 * The {@linkplain #getNestHost() nest host} of that nest is the zeroth
4005 * element of the array. Subsequent elements represent any classes or
4006 * interfaces that are recorded by the nest host as being members of
4007 * the nest; the order of such elements is unspecified. Duplicates are
4008 * permitted.
4009 * If the nest host of that nest does not enumerate any members, then the
4010 * array has a single element containing {@code this}.
4011 *
4012 * <p>Each of the {@code Class} objects representing array types,
4013 * primitive types, and {@code void} returns an array containing only
4014 * {@code this}.
4015 *
4016 * <p>This method validates that, for each class or interface which is
4017 * recorded as a member of the nest by the nest host, that class or
4018 * interface records itself as a member of that same nest. Any exceptions
4019 * that occur during this validation are rethrown by this method.
4020 *
4021 * @return an array of all classes and interfaces in the same nest as
4022 * this class
4023 *
4024 * @throws LinkageError
4025 * If there is any problem loading or validating a nest member or
4026 * its nest host
4027 * @throws SecurityException
4028 * If any returned class is not the current class, and
4029 * if a security manager, <i>s</i>, is present and the caller's
4030 * class loader is not the same as or an ancestor of the class
4031 * loader for that returned class and invocation of {@link
4032 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
4033 * denies access to the package of that returned class
4034 *
4035 * @since 11
4036 * @see #getNestHost()
4037 */
4038 @CallerSensitive
4039 public Class<?>[] getNestMembers() {
4040 if (isPrimitive() || isArray()) {
4041 return new Class<?>[] { this };
4042 }
4043 Class<?>[] members = getNestMembers0();
4044 // Can't actually enable this due to bootstrapping issues
4045 // assert(members.length != 1 || members[0] == this); // expected invariant from VM
4046
4047 if (members.length > 1) {
4048 // If we return anything other than the current class we need
4049 // a security check
4050 SecurityManager sm = System.getSecurityManager();
4051 if (sm != null) {
4052 checkPackageAccess(sm,
4053 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
4054 }
4055 }
4056 return members;
4057 }
4058 }