1 /*
2 * Copyright (c) 1994, 2016, 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.reflect.AnnotatedElement;
31 import java.lang.reflect.Array;
32 import java.lang.reflect.GenericArrayType;
33 import java.lang.reflect.GenericDeclaration;
34 import java.lang.reflect.Member;
35 import java.lang.reflect.Field;
36 import java.lang.reflect.Executable;
37 import java.lang.reflect.Method;
38 import java.lang.reflect.Module;
39 import java.lang.reflect.Constructor;
40 import java.lang.reflect.Modifier;
41 import java.lang.reflect.Type;
42 import java.lang.reflect.TypeVariable;
43 import java.lang.reflect.InvocationTargetException;
44 import java.lang.reflect.AnnotatedType;
45 import java.lang.reflect.Proxy;
46 import java.lang.ref.SoftReference;
47 import java.io.IOException;
48 import java.io.InputStream;
49 import java.io.ObjectStreamField;
50 import java.net.URL;
51 import java.security.AccessController;
52 import java.security.PrivilegedAction;
53 import java.util.ArrayList;
54 import java.util.Arrays;
55 import java.util.Collection;
56 import java.util.HashSet;
57 import java.util.LinkedHashMap;
58 import java.util.List;
59 import java.util.Set;
60 import java.util.Map;
61 import java.util.HashMap;
62 import java.util.Objects;
63 import java.util.StringJoiner;
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.misc.VM;
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 sun.reflect.generics.factory.CoreReflectionFactory;
74 import sun.reflect.generics.factory.GenericsFactory;
75 import sun.reflect.generics.repository.ClassRepository;
76 import sun.reflect.generics.repository.MethodRepository;
77 import sun.reflect.generics.repository.ConstructorRepository;
78 import sun.reflect.generics.scope.ClassScope;
79 import sun.security.util.SecurityConstants;
80 import sun.reflect.annotation.*;
81 import sun.reflect.misc.ReflectUtil;
82
83 /**
84 * Instances of the class {@code Class} represent classes and
85 * interfaces in a running Java application. An enum is a kind of
86 * class and an annotation is a kind of interface. Every array also
87 * belongs to a class that is reflected as a {@code Class} object
88 * that is shared by all arrays with the same element type and number
89 * of dimensions. The primitive Java types ({@code boolean},
90 * {@code byte}, {@code char}, {@code short},
91 * {@code int}, {@code long}, {@code float}, and
92 * {@code double}), and the keyword {@code void} are also
93 * represented as {@code Class} objects.
94 *
95 * <p> {@code Class} has no public constructor. Instead {@code Class}
96 * objects are constructed automatically by the Java Virtual Machine as classes
97 * are loaded and by calls to the {@code defineClass} method in the class
98 * loader.
99 *
100 * <p> The following example uses a {@code Class} object to print the
101 * class name of an object:
102 *
103 * <blockquote><pre>
104 * void printClassName(Object obj) {
105 * System.out.println("The class of " + obj +
106 * " is " + obj.getClass().getName());
107 * }
108 * </pre></blockquote>
109 *
110 * <p> It is also possible to get the {@code Class} object for a named
111 * type (or for void) using a class literal. See Section 15.8.2 of
112 * <cite>The Java™ Language Specification</cite>.
113 * For example:
114 *
115 * <blockquote>
116 * {@code System.out.println("The name of class Foo is: "+Foo.class.getName());}
117 * </blockquote>
118 *
119 * @param <T> the type of the class modeled by this {@code Class}
120 * object. For example, the type of {@code String.class} is {@code
121 * Class<String>}. Use {@code Class<?>} if the class being modeled is
122 * unknown.
123 *
124 * @author unascribed
125 * @see java.lang.ClassLoader#defineClass(byte[], int, int)
126 * @since 1.0
127 */
128 public final class Class<T> implements java.io.Serializable,
129 GenericDeclaration,
130 Type,
131 AnnotatedElement {
132 private static final int ANNOTATION= 0x00002000;
133 private static final int ENUM = 0x00004000;
134 private static final int SYNTHETIC = 0x00001000;
135
136 private static native void registerNatives();
137 static {
138 registerNatives();
139 }
140
141 /*
142 * Private constructor. Only the Java Virtual Machine creates Class objects.
143 * This constructor is not used and prevents the default constructor being
144 * generated.
145 */
146 private Class(ClassLoader loader, Class<?> arrayComponentType) {
147 // Initialize final field for classLoader. The initialization value of non-null
148 // prevents future JIT optimizations from assuming this final field is null.
149 classLoader = loader;
150 componentType = arrayComponentType;
151 }
152
153 /**
154 * Converts the object to a string. The string representation is the
155 * string "class" or "interface", followed by a space, and then by the
156 * fully qualified name of the class in the format returned by
157 * {@code getName}. If this {@code Class} object represents a
158 * primitive type, this method returns the name of the primitive type. If
159 * this {@code Class} object represents void this method returns
160 * "void". If this {@code Class} object represents an array type,
161 * this method returns "class " followed by {@code getName}.
162 *
163 * @return a string representation of this class object.
164 */
165 public String toString() {
166 return (isInterface() ? "interface " : (isPrimitive() ? "" : "class "))
167 + getName();
168 }
169
170 /**
171 * Returns a string describing this {@code Class}, including
172 * information about modifiers and type parameters.
173 *
174 * The string is formatted as a list of type modifiers, if any,
175 * followed by the kind of type (empty string for primitive types
176 * and {@code class}, {@code enum}, {@code interface}, or
177 * <code>@</code>{@code interface}, as appropriate), followed
178 * by the type's name, followed by an angle-bracketed
179 * comma-separated list of the type's type parameters, if any.
180 *
181 * A space is used to separate modifiers from one another and to
182 * separate any modifiers from the kind of type. The modifiers
183 * occur in canonical order. If there are no type parameters, the
184 * type parameter list is elided.
185 *
186 * For an array type, the string starts with the type name,
187 * followed by an angle-bracketed comma-separated list of the
188 * type's type parameters, if any, followed by a sequence of
189 * {@code []} characters, one set of brackets per dimension of
190 * the array.
191 *
192 * <p>Note that since information about the runtime representation
193 * of a type is being generated, modifiers not present on the
194 * originating source code or illegal on the originating source
195 * code may be present.
196 *
197 * @return a string describing this {@code Class}, including
198 * information about modifiers and type parameters
199 *
200 * @since 1.8
201 */
202 public String toGenericString() {
203 if (isPrimitive()) {
204 return toString();
205 } else {
206 StringBuilder sb = new StringBuilder();
207 Class<?> component = this;
208 int arrayDepth = 0;
209
210 if (isArray()) {
211 do {
212 arrayDepth++;
213 component = component.getComponentType();
214 } while (component.isArray());
215 sb.append(component.getName());
216 } else {
217 // Class modifiers are a superset of interface modifiers
218 int modifiers = getModifiers() & Modifier.classModifiers();
219 if (modifiers != 0) {
220 sb.append(Modifier.toString(modifiers));
221 sb.append(' ');
222 }
223
224 if (isAnnotation()) {
225 sb.append('@');
226 }
227 if (isInterface()) { // Note: all annotation types are interfaces
228 sb.append("interface");
229 } else {
230 if (isEnum())
231 sb.append("enum");
232 else
233 sb.append("class");
234 }
235 sb.append(' ');
236 sb.append(getName());
237 }
238
239 TypeVariable<?>[] typeparms = component.getTypeParameters();
240 if (typeparms.length > 0) {
241 boolean first = true;
242 sb.append('<');
243 for(TypeVariable<?> typeparm: typeparms) {
244 if (!first)
245 sb.append(',');
246 sb.append(typeparm.getTypeName());
247 first = false;
248 }
249 sb.append('>');
250 }
251
252 for (int i = 0; i < arrayDepth; i++)
253 sb.append("[]");
254
255 return sb.toString();
256 }
257 }
258
259 /**
260 * Returns the {@code Class} object associated with the class or
261 * interface with the given string name. Invoking this method is
262 * equivalent to:
263 *
264 * <blockquote>
265 * {@code Class.forName(className, true, currentLoader)}
266 * </blockquote>
267 *
268 * where {@code currentLoader} denotes the defining class loader of
269 * the current class.
270 *
271 * <p> For example, the following code fragment returns the
272 * runtime {@code Class} descriptor for the class named
273 * {@code java.lang.Thread}:
274 *
275 * <blockquote>
276 * {@code Class t = Class.forName("java.lang.Thread")}
277 * </blockquote>
278 * <p>
279 * A call to {@code forName("X")} causes the class named
280 * {@code X} to be initialized.
281 *
282 * @param className the fully qualified name of the desired class.
283 * @return the {@code Class} object for the class with the
284 * specified name.
285 * @exception LinkageError if the linkage fails
286 * @exception ExceptionInInitializerError if the initialization provoked
287 * by this method fails
288 * @exception ClassNotFoundException if the class cannot be located
289 */
290 @CallerSensitive
291 public static Class<?> forName(String className)
292 throws ClassNotFoundException {
293 Class<?> caller = Reflection.getCallerClass();
294 return forName0(className, true, ClassLoader.getClassLoader(caller), caller);
295 }
296
297
298 /**
299 * Returns the {@code Class} object associated with the class or
300 * interface with the given string name, using the given class loader.
301 * Given the fully qualified name for a class or interface (in the same
302 * format returned by {@code getName}) this method attempts to
303 * locate, load, and link the class or interface. The specified class
304 * loader is used to load the class or interface. If the parameter
305 * {@code loader} is null, the class is loaded through the bootstrap
306 * class loader. The class is initialized only if the
307 * {@code initialize} parameter is {@code true} and if it has
308 * not been initialized earlier.
309 *
310 * <p> If {@code name} denotes a primitive type or void, an attempt
311 * will be made to locate a user-defined class in the unnamed package whose
312 * name is {@code name}. Therefore, this method cannot be used to
313 * obtain any of the {@code Class} objects representing primitive
314 * types or void.
315 *
316 * <p> If {@code name} denotes an array class, the component type of
317 * the array class is loaded but not initialized.
318 *
319 * <p> For example, in an instance method the expression:
320 *
321 * <blockquote>
322 * {@code Class.forName("Foo")}
323 * </blockquote>
324 *
325 * is equivalent to:
326 *
327 * <blockquote>
328 * {@code Class.forName("Foo", true, this.getClass().getClassLoader())}
329 * </blockquote>
330 *
331 * Note that this method throws errors related to loading, linking or
332 * initializing as specified in Sections 12.2, 12.3 and 12.4 of <em>The
333 * Java Language Specification</em>.
334 * Note that this method does not check whether the requested class
335 * is accessible to its caller.
336 *
337 * <p> If the {@code loader} is {@code null}, and a security
338 * manager is present, and the caller's class loader is not null, then this
339 * method calls the security manager's {@code checkPermission} method
340 * with a {@code RuntimePermission("getClassLoader")} permission to
341 * ensure it's ok to access the bootstrap class loader.
342 *
343 * @param name fully qualified name of the desired class
344 * @param initialize if {@code true} the class will be initialized.
345 * See Section 12.4 of <em>The Java Language Specification</em>.
346 * @param loader class loader from which the class must be loaded
347 * @return class object representing the desired class
348 *
349 * @exception LinkageError if the linkage fails
350 * @exception ExceptionInInitializerError if the initialization provoked
351 * by this method fails
352 * @exception ClassNotFoundException if the class cannot be located by
353 * the specified class loader
354 *
355 * @see java.lang.Class#forName(String)
356 * @see java.lang.ClassLoader
357 * @since 1.2
358 */
359 @CallerSensitive
360 public static Class<?> forName(String name, boolean initialize,
361 ClassLoader loader)
362 throws ClassNotFoundException
363 {
364 Class<?> caller = null;
365 SecurityManager sm = System.getSecurityManager();
366 if (sm != null) {
367 // Reflective call to get caller class is only needed if a security manager
368 // is present. Avoid the overhead of making this call otherwise.
369 caller = Reflection.getCallerClass();
370 if (VM.isSystemDomainLoader(loader)) {
371 ClassLoader ccl = ClassLoader.getClassLoader(caller);
372 if (!VM.isSystemDomainLoader(ccl)) {
373 sm.checkPermission(
374 SecurityConstants.GET_CLASSLOADER_PERMISSION);
375 }
376 }
377 }
378 return forName0(name, initialize, loader, caller);
379 }
380
381 /** Called after security check for system loader access checks have been made. */
382 private static native Class<?> forName0(String name, boolean initialize,
383 ClassLoader loader,
384 Class<?> caller)
385 throws ClassNotFoundException;
386
387
388 /**
389 * Returns the {@code Class} with the given <a href="ClassLoader.html#name">
390 * binary name</a> in the given module.
391 *
392 * <p> This method attempts to locate, load, and link the class or interface.
393 * It does not run the class initializer. If the class is not found, this
394 * method returns {@code null}. </p>
395 *
396 * <p> If the class loader of the given module defines other modules and
397 * the given name is a class defined in a different module, this method
398 * returns {@code null} after the class is loaded. </p>
399 *
400 * <p> This method does not check whether the requested class is
401 * accessible to its caller. </p>
402 *
403 * @apiNote
404 * This method returns {@code null} on failure rather than
405 * throwing a {@link ClassNotFoundException}, as is done by
406 * the {@link #forName(String, boolean, ClassLoader)} method.
407 * The security check is a stack-based permission check if the caller
408 * loads a class in another module.
409 *
410 * @param module A module
411 * @param name The <a href="ClassLoader.html#name">binary name</a>
412 * of the class
413 * @return {@code Class} object of the given name defined in the given module;
414 * {@code null} if not found.
415 *
416 * @throws NullPointerException if the given module or name is {@code null}
417 *
418 * @throws LinkageError if the linkage fails
419 *
420 * @throws SecurityException
421 * <ul>
422 * <li> if the caller is not the specified module and
423 * {@code RuntimePermission("getClassLoader")} permission is denied; or</li>
424 * <li> access to the module content is denied. For example,
425 * permission check will be performed when a class loader calls
426 * {@link ModuleReader#open(String)} to read the bytes of a class file
427 * in a module.</li>
428 * </ul>
429 *
430 * @since 9
431 */
432 @CallerSensitive
433 public static Class<?> forName(Module module, String name) {
434 Objects.requireNonNull(module);
435 Objects.requireNonNull(name);
436
437 Class<?> caller = Reflection.getCallerClass();
438 if (caller != null && caller.getModule() != module) {
439 // if caller is null, Class.forName is the last java frame on the stack.
440 // java.base has all permissions
441 SecurityManager sm = System.getSecurityManager();
442 if (sm != null) {
443 sm.checkPermission(SecurityConstants.GET_CLASSLOADER_PERMISSION);
444 }
445 }
446
447 PrivilegedAction<ClassLoader> pa = module::getClassLoader;
448 ClassLoader cl = AccessController.doPrivileged(pa);
449 if (module.isNamed() && cl != null) {
450 return cl.loadLocalClass(module, name);
451 }
452
453 final Class<?> c;
454 if (cl != null) {
455 c = cl.loadLocalClass(name);
456 } else {
457 c = BootLoader.loadClassOrNull(name);
458 }
459
460 if (c != null && c.getModule() == module) {
461 return c;
462 } else {
463 return null;
464 }
465 }
466
467 /**
468 * Creates a new instance of the class represented by this {@code Class}
469 * object. The class is instantiated as if by a {@code new}
470 * expression with an empty argument list. The class is initialized if it
471 * has not already been initialized.
472 *
473 * @deprecated This method propagates any exception thrown by the
474 * nullary constructor, including a checked exception. Use of
475 * this method effectively bypasses the compile-time exception
476 * checking that would otherwise be performed by the compiler.
477 * The {@link
478 * java.lang.reflect.Constructor#newInstance(java.lang.Object...)
479 * Constructor.newInstance} method avoids this problem by wrapping
480 * any exception thrown by the constructor in a (checked) {@link
481 * java.lang.reflect.InvocationTargetException}.
482 *
483 * <p>The call
484 *
485 * <pre>{@code
486 * clazz.newInstance()
487 * }</pre>
488 *
489 * can be replaced by
490 *
491 * <pre>{@code
492 * clazz.getConstructor().newInstance()
493 * }</pre>
494 *
495 * The latter sequence of calls is inferred to be able to throw
496 * the additional exception types {@link
497 * InvocationTargetException} and {@link
498 * NoSuchMethodException}. Both of these exception types are
499 * subclasses of {@link ReflectiveOperationException}.
500 *
501 * @return a newly allocated instance of the class represented by this
502 * object.
503 * @throws IllegalAccessException if the class or its nullary
504 * constructor is not accessible.
505 * @throws InstantiationException
506 * if this {@code Class} represents an abstract class,
507 * an interface, an array class, a primitive type, or void;
508 * or if the class has no nullary constructor;
509 * or if the instantiation fails for some other reason.
510 * @throws ExceptionInInitializerError if the initialization
511 * provoked by this method fails.
512 * @throws SecurityException
513 * If a security manager, <i>s</i>, is present and
514 * the caller's class loader is not the same as or an
515 * ancestor of the class loader for the current class and
516 * invocation of {@link SecurityManager#checkPackageAccess
517 * s.checkPackageAccess()} denies access to the package
518 * of this class.
519 */
520 @CallerSensitive
521 @Deprecated(since="9")
522 public T newInstance()
523 throws InstantiationException, IllegalAccessException
524 {
525 if (System.getSecurityManager() != null) {
526 checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), false);
527 }
528
529 // NOTE: the following code may not be strictly correct under
530 // the current Java memory model.
531
532 // Constructor lookup
533 if (cachedConstructor == null) {
534 if (this == Class.class) {
535 throw new IllegalAccessException(
536 "Can not call newInstance() on the Class for java.lang.Class"
537 );
538 }
539 try {
540 Class<?>[] empty = {};
541 final Constructor<T> c = getConstructor0(empty, Member.DECLARED);
542 // Disable accessibility checks on the constructor
543 // since we have to do the security check here anyway
544 // (the stack depth is wrong for the Constructor's
545 // security check to work)
546 java.security.AccessController.doPrivileged(
547 new java.security.PrivilegedAction<>() {
548 public Void run() {
549 c.setAccessible(true);
550 return null;
551 }
552 });
553 cachedConstructor = c;
554 } catch (NoSuchMethodException e) {
555 throw (InstantiationException)
556 new InstantiationException(getName()).initCause(e);
557 }
558 }
559 Constructor<T> tmpConstructor = cachedConstructor;
560 // Security check (same as in java.lang.reflect.Constructor)
561 Class<?> caller = Reflection.getCallerClass();
562 if (newInstanceCallerCache != caller) {
563 int modifiers = tmpConstructor.getModifiers();
564 Reflection.ensureMemberAccess(caller, this, null, modifiers);
565 newInstanceCallerCache = caller;
566 }
567 // Run constructor
568 try {
569 return tmpConstructor.newInstance((Object[])null);
570 } catch (InvocationTargetException e) {
571 Unsafe.getUnsafe().throwException(e.getTargetException());
572 // Not reached
573 return null;
574 }
575 }
576 private transient volatile Constructor<T> cachedConstructor;
577 private transient volatile Class<?> newInstanceCallerCache;
578
579
580 /**
581 * Determines if the specified {@code Object} is assignment-compatible
582 * with the object represented by this {@code Class}. This method is
583 * the dynamic equivalent of the Java language {@code instanceof}
584 * operator. The method returns {@code true} if the specified
585 * {@code Object} argument is non-null and can be cast to the
586 * reference type represented by this {@code Class} object without
587 * raising a {@code ClassCastException.} It returns {@code false}
588 * otherwise.
589 *
590 * <p> Specifically, if this {@code Class} object represents a
591 * declared class, this method returns {@code true} if the specified
592 * {@code Object} argument is an instance of the represented class (or
593 * of any of its subclasses); it returns {@code false} otherwise. If
594 * this {@code Class} object represents an array class, this method
595 * returns {@code true} if the specified {@code Object} argument
596 * can be converted to an object of the array class by an identity
597 * conversion or by a widening reference conversion; it returns
598 * {@code false} otherwise. If this {@code Class} object
599 * represents an interface, this method returns {@code true} if the
600 * class or any superclass of the specified {@code Object} argument
601 * implements this interface; it returns {@code false} otherwise. If
602 * this {@code Class} object represents a primitive type, this method
603 * returns {@code false}.
604 *
605 * @param obj the object to check
606 * @return true if {@code obj} is an instance of this class
607 *
608 * @since 1.1
609 */
610 @HotSpotIntrinsicCandidate
611 public native boolean isInstance(Object obj);
612
613
614 /**
615 * Determines if the class or interface represented by this
616 * {@code Class} object is either the same as, or is a superclass or
617 * superinterface of, the class or interface represented by the specified
618 * {@code Class} parameter. It returns {@code true} if so;
619 * otherwise it returns {@code false}. If this {@code Class}
620 * object represents a primitive type, this method returns
621 * {@code true} if the specified {@code Class} parameter is
622 * exactly this {@code Class} object; otherwise it returns
623 * {@code false}.
624 *
625 * <p> Specifically, this method tests whether the type represented by the
626 * specified {@code Class} parameter can be converted to the type
627 * represented by this {@code Class} object via an identity conversion
628 * or via a widening reference conversion. See <em>The Java Language
629 * Specification</em>, sections 5.1.1 and 5.1.4 , for details.
630 *
631 * @param cls the {@code Class} object to be checked
632 * @return the {@code boolean} value indicating whether objects of the
633 * type {@code cls} can be assigned to objects of this class
634 * @exception NullPointerException if the specified Class parameter is
635 * null.
636 * @since 1.1
637 */
638 @HotSpotIntrinsicCandidate
639 public native boolean isAssignableFrom(Class<?> cls);
640
641
642 /**
643 * Determines if the specified {@code Class} object represents an
644 * interface type.
645 *
646 * @return {@code true} if this object represents an interface;
647 * {@code false} otherwise.
648 */
649 @HotSpotIntrinsicCandidate
650 public native boolean isInterface();
651
652
653 /**
654 * Determines if this {@code Class} object represents an array class.
655 *
656 * @return {@code true} if this object represents an array class;
657 * {@code false} otherwise.
658 * @since 1.1
659 */
660 @HotSpotIntrinsicCandidate
661 public native boolean isArray();
662
663
664 /**
665 * Determines if the specified {@code Class} object represents a
666 * primitive type.
667 *
668 * <p> There are nine predefined {@code Class} objects to represent
669 * the eight primitive types and void. These are created by the Java
670 * Virtual Machine, and have the same names as the primitive types that
671 * they represent, namely {@code boolean}, {@code byte},
672 * {@code char}, {@code short}, {@code int},
673 * {@code long}, {@code float}, and {@code double}.
674 *
675 * <p> These objects may only be accessed via the following public static
676 * final variables, and are the only {@code Class} objects for which
677 * this method returns {@code true}.
678 *
679 * @return true if and only if this class represents a primitive type
680 *
681 * @see java.lang.Boolean#TYPE
682 * @see java.lang.Character#TYPE
683 * @see java.lang.Byte#TYPE
684 * @see java.lang.Short#TYPE
685 * @see java.lang.Integer#TYPE
686 * @see java.lang.Long#TYPE
687 * @see java.lang.Float#TYPE
688 * @see java.lang.Double#TYPE
689 * @see java.lang.Void#TYPE
690 * @since 1.1
691 */
692 @HotSpotIntrinsicCandidate
693 public native boolean isPrimitive();
694
695 /**
696 * Returns true if this {@code Class} object represents an annotation
697 * type. Note that if this method returns true, {@link #isInterface()}
698 * would also return true, as all annotation types are also interfaces.
699 *
700 * @return {@code true} if this class object represents an annotation
701 * type; {@code false} otherwise
702 * @since 1.5
703 */
704 public boolean isAnnotation() {
705 return (getModifiers() & ANNOTATION) != 0;
706 }
707
708 /**
709 * Returns {@code true} if this class is a synthetic class;
710 * returns {@code false} otherwise.
711 * @return {@code true} if and only if this class is a synthetic class as
712 * defined by the Java Language Specification.
713 * @jls 13.1 The Form of a Binary
714 * @since 1.5
715 */
716 public boolean isSynthetic() {
717 return (getModifiers() & SYNTHETIC) != 0;
718 }
719
720 /**
721 * Returns the name of the entity (class, interface, array class,
722 * primitive type, or void) represented by this {@code Class} object,
723 * as a {@code String}.
724 *
725 * <p> If this class object represents a reference type that is not an
726 * array type then the binary name of the class is returned, as specified
727 * by
728 * <cite>The Java™ Language Specification</cite>.
729 *
730 * <p> If this class object represents a primitive type or void, then the
731 * name returned is a {@code String} equal to the Java language
732 * keyword corresponding to the primitive type or void.
733 *
734 * <p> If this class object represents a class of arrays, then the internal
735 * form of the name consists of the name of the element type preceded by
736 * one or more '{@code [}' characters representing the depth of the array
737 * nesting. The encoding of element type names is as follows:
738 *
739 * <blockquote><table summary="Element types and encodings">
740 * <tr><th> Element Type <th> <th> Encoding
741 * <tr><td> boolean <td> <td align=center> Z
742 * <tr><td> byte <td> <td align=center> B
743 * <tr><td> char <td> <td align=center> C
744 * <tr><td> class or interface
745 * <td> <td align=center> L<i>classname</i>;
746 * <tr><td> double <td> <td align=center> D
747 * <tr><td> float <td> <td align=center> F
748 * <tr><td> int <td> <td align=center> I
749 * <tr><td> long <td> <td align=center> J
750 * <tr><td> short <td> <td align=center> S
751 * </table></blockquote>
752 *
753 * <p> The class or interface name <i>classname</i> is the binary name of
754 * the class specified above.
755 *
756 * <p> Examples:
757 * <blockquote><pre>
758 * String.class.getName()
759 * returns "java.lang.String"
760 * byte.class.getName()
761 * returns "byte"
762 * (new Object[3]).getClass().getName()
763 * returns "[Ljava.lang.Object;"
764 * (new int[3][4][5][6][7][8][9]).getClass().getName()
765 * returns "[[[[[[[I"
766 * </pre></blockquote>
767 *
768 * @return the name of the class or interface
769 * represented by this object.
770 */
771 public String getName() {
772 String name = this.name;
773 if (name == null)
774 this.name = name = getName0();
775 return name;
776 }
777
778 // cache the name to reduce the number of calls into the VM
779 private transient String name;
780 private native String getName0();
781
782 /**
783 * Returns the class loader for the class. Some implementations may use
784 * null to represent the bootstrap class loader. This method will return
785 * null in such implementations if this class was loaded by the bootstrap
786 * class loader.
787 *
788 * <p> If a security manager is present, and the caller's class loader is
789 * not null and the caller's class loader is not the same as or an ancestor of
790 * the class loader for the class whose class loader is requested, then
791 * this method calls the security manager's {@code checkPermission}
792 * method with a {@code RuntimePermission("getClassLoader")}
793 * permission to ensure it's ok to access the class loader for the class.
794 *
795 * <p>If this object
796 * represents a primitive type or void, null is returned.
797 *
798 * @return the class loader that loaded the class or interface
799 * represented by this object.
800 * @throws SecurityException
801 * if a security manager exists and its
802 * {@code checkPermission} method denies
803 * access to the class loader for the class.
804 * @see java.lang.ClassLoader
805 * @see SecurityManager#checkPermission
806 * @see java.lang.RuntimePermission
807 */
808 @CallerSensitive
809 public ClassLoader getClassLoader() {
810 ClassLoader cl = getClassLoader0();
811 if (cl == null)
812 return null;
813 SecurityManager sm = System.getSecurityManager();
814 if (sm != null) {
815 ClassLoader.checkClassLoaderPermission(cl, Reflection.getCallerClass());
816 }
817 return cl;
818 }
819
820 // Package-private to allow ClassLoader access
821 ClassLoader getClassLoader0() { return classLoader; }
822
823 /**
824 * Returns the module that this class or interface is a member of.
825 *
826 * If this class represents an array type then this method returns the
827 * {@code Module} for the element type. If this class represents a
828 * primitive type or void, then the {@code Module} object for the
829 * {@code java.base} module is returned.
830 *
831 * If this class is in an unnamed module then the {@link
832 * ClassLoader#getUnnamedModule() unnamed} {@code Module} of the class
833 * loader for this class is returned.
834 *
835 * @return the module that this class or interface is a member of
836 *
837 * @since 9
838 */
839 public Module getModule() {
840 return module;
841 }
842
843 // set by VM
844 private transient Module module;
845
846 // Initialized in JVM not by private constructor
847 // This field is filtered from reflection access, i.e. getDeclaredField
848 // will throw NoSuchFieldException
849 private final ClassLoader classLoader;
850
851 /**
852 * Returns an array of {@code TypeVariable} objects that represent the
853 * type variables declared by the generic declaration represented by this
854 * {@code GenericDeclaration} object, in declaration order. Returns an
855 * array of length 0 if the underlying generic declaration declares no type
856 * variables.
857 *
858 * @return an array of {@code TypeVariable} objects that represent
859 * the type variables declared by this generic declaration
860 * @throws java.lang.reflect.GenericSignatureFormatError if the generic
861 * signature of this generic declaration does not conform to
862 * the format specified in
863 * <cite>The Java™ Virtual Machine Specification</cite>
864 * @since 1.5
865 */
866 @SuppressWarnings("unchecked")
867 public TypeVariable<Class<T>>[] getTypeParameters() {
868 ClassRepository info = getGenericInfo();
869 if (info != null)
870 return (TypeVariable<Class<T>>[])info.getTypeParameters();
871 else
872 return (TypeVariable<Class<T>>[])new TypeVariable<?>[0];
873 }
874
875
876 /**
877 * Returns the {@code Class} representing the direct superclass of the
878 * entity (class, interface, primitive type or void) represented by
879 * this {@code Class}. If this {@code Class} represents either the
880 * {@code Object} class, an interface, a primitive type, or void, then
881 * null is returned. If this object represents an array class then the
882 * {@code Class} object representing the {@code Object} class is
883 * returned.
884 *
885 * @return the direct superclass of the class represented by this object
886 */
887 @HotSpotIntrinsicCandidate
888 public native Class<? super T> getSuperclass();
889
890
891 /**
892 * Returns the {@code Type} representing the direct superclass of
893 * the entity (class, interface, primitive type or void) represented by
894 * this {@code Class}.
895 *
896 * <p>If the superclass is a parameterized type, the {@code Type}
897 * object returned must accurately reflect the actual type
898 * parameters used in the source code. The parameterized type
899 * representing the superclass is created if it had not been
900 * created before. See the declaration of {@link
901 * java.lang.reflect.ParameterizedType ParameterizedType} for the
902 * semantics of the creation process for parameterized types. If
903 * this {@code Class} represents either the {@code Object}
904 * class, an interface, a primitive type, or void, then null is
905 * returned. If this object represents an array class then the
906 * {@code Class} object representing the {@code Object} class is
907 * returned.
908 *
909 * @throws java.lang.reflect.GenericSignatureFormatError if the generic
910 * class signature does not conform to the format specified in
911 * <cite>The Java™ Virtual Machine Specification</cite>
912 * @throws TypeNotPresentException if the generic superclass
913 * refers to a non-existent type declaration
914 * @throws java.lang.reflect.MalformedParameterizedTypeException if the
915 * generic superclass refers to a parameterized type that cannot be
916 * instantiated for any reason
917 * @return the direct superclass of the class represented by this object
918 * @since 1.5
919 */
920 public Type getGenericSuperclass() {
921 ClassRepository info = getGenericInfo();
922 if (info == null) {
923 return getSuperclass();
924 }
925
926 // Historical irregularity:
927 // Generic signature marks interfaces with superclass = Object
928 // but this API returns null for interfaces
929 if (isInterface()) {
930 return null;
931 }
932
933 return info.getSuperclass();
934 }
935
936 /**
937 * Gets the package of this class.
938 *
939 * <p>If this class represents an array type, a primitive type or void,
940 * this method returns {@code null}.
941 *
942 * @return the package of this class.
943 */
944 public Package getPackage() {
945 if (isPrimitive() || isArray()) {
946 return null;
947 }
948 ClassLoader cl = getClassLoader0();
949 return cl != null ? cl.definePackage(this)
950 : BootLoader.definePackage(this);
951 }
952
953 /**
954 * Returns the fully qualified package name.
955 *
956 * <p> If this class is a top level class, then this method returns the fully
957 * qualified name of the package that the class is a member of, or the
958 * empty string if the class is in an unnamed package.
959 *
960 * <p> If this class is a member class, then this method is equivalent to
961 * invoking {@code getPackageName()} on the {@link #getEnclosingClass
962 * enclosing class}.
963 *
964 * <p> If this class is a {@link #isLocalClass local class} or an {@link
965 * #isAnonymousClass() anonymous class}, then this method is equivalent to
966 * invoking {@code getPackageName()} on the {@link #getDeclaringClass
967 * declaring class} of the {@link #getEnclosingMethod enclosing method} or
968 * {@link #getEnclosingConstructor enclosing constructor}.
969 *
970 * <p> This method returns {@code null} if this class represents an array type,
971 * a primitive type or void.
972 *
973 * @return the fully qualified package name
974 *
975 * @since 9
976 * @jls 6.7 Fully Qualified Names
977 */
978 public String getPackageName() {
979 String pn = this.packageName;
980 if (pn == null && !isArray() && !isPrimitive()) {
981 String cn = getName();
982 int dot = cn.lastIndexOf('.');
983 pn = (dot != -1) ? cn.substring(0, dot).intern() : "";
984 this.packageName = pn;
985 }
986 return pn;
987 }
988
989 // cached package name
990 private String packageName;
991
992 /**
993 * Returns the interfaces directly implemented by the class or interface
994 * represented by this object.
995 *
996 * <p>If this object represents a class, the return value is an array
997 * containing objects representing all interfaces directly implemented by
998 * the class. The order of the interface objects in the array corresponds
999 * to the order of the interface names in the {@code implements} clause of
1000 * the declaration of the class represented by this object. For example,
1001 * given the declaration:
1002 * <blockquote>
1003 * {@code class Shimmer implements FloorWax, DessertTopping { ... }}
1004 * </blockquote>
1005 * suppose the value of {@code s} is an instance of
1006 * {@code Shimmer}; the value of the expression:
1007 * <blockquote>
1008 * {@code s.getClass().getInterfaces()[0]}
1009 * </blockquote>
1010 * is the {@code Class} object that represents interface
1011 * {@code FloorWax}; and the value of:
1012 * <blockquote>
1013 * {@code s.getClass().getInterfaces()[1]}
1014 * </blockquote>
1015 * is the {@code Class} object that represents interface
1016 * {@code DessertTopping}.
1017 *
1018 * <p>If this object represents an interface, the array contains objects
1019 * representing all interfaces directly extended by the interface. The
1020 * order of the interface objects in the array corresponds to the order of
1021 * the interface names in the {@code extends} clause of the declaration of
1022 * the interface represented by this object.
1023 *
1024 * <p>If this object represents a class or interface that implements no
1025 * interfaces, the method returns an array of length 0.
1026 *
1027 * <p>If this object represents a primitive type or void, the method
1028 * returns an array of length 0.
1029 *
1030 * <p>If this {@code Class} object represents an array type, the
1031 * interfaces {@code Cloneable} and {@code java.io.Serializable} are
1032 * returned in that order.
1033 *
1034 * @return an array of interfaces directly implemented by this class
1035 */
1036 public Class<?>[] getInterfaces() {
1037 ReflectionData<T> rd = reflectionData();
1038 if (rd == null) {
1039 // no cloning required
1040 return getInterfaces0();
1041 } else {
1042 Class<?>[] interfaces = rd.interfaces;
1043 if (interfaces == null) {
1044 interfaces = getInterfaces0();
1045 rd.interfaces = interfaces;
1046 }
1047 // defensively copy before handing over to user code
1048 return interfaces.clone();
1049 }
1050 }
1051
1052 private native Class<?>[] getInterfaces0();
1053
1054 /**
1055 * Returns the {@code Type}s representing the interfaces
1056 * directly implemented by the class or interface represented by
1057 * this object.
1058 *
1059 * <p>If a superinterface is a parameterized type, the
1060 * {@code Type} object returned for it must accurately reflect
1061 * the actual type parameters used in the source code. The
1062 * parameterized type representing each superinterface is created
1063 * if it had not been created before. See the declaration of
1064 * {@link java.lang.reflect.ParameterizedType ParameterizedType}
1065 * for the semantics of the creation process for parameterized
1066 * types.
1067 *
1068 * <p>If this object represents a class, the return value is an array
1069 * containing objects representing all interfaces directly implemented by
1070 * the class. The order of the interface objects in the array corresponds
1071 * to the order of the interface names in the {@code implements} clause of
1072 * the declaration of the class represented by this object.
1073 *
1074 * <p>If this object represents an interface, the array contains objects
1075 * representing all interfaces directly extended by the interface. The
1076 * order of the interface objects in the array corresponds to the order of
1077 * the interface names in the {@code extends} clause of the declaration of
1078 * the interface represented by this object.
1079 *
1080 * <p>If this object represents a class or interface that implements no
1081 * interfaces, the method returns an array of length 0.
1082 *
1083 * <p>If this object represents a primitive type or void, the method
1084 * returns an array of length 0.
1085 *
1086 * <p>If this {@code Class} object represents an array type, the
1087 * interfaces {@code Cloneable} and {@code java.io.Serializable} are
1088 * returned in that order.
1089 *
1090 * @throws java.lang.reflect.GenericSignatureFormatError
1091 * if the generic class signature does not conform to the format
1092 * specified in
1093 * <cite>The Java™ Virtual Machine Specification</cite>
1094 * @throws TypeNotPresentException if any of the generic
1095 * superinterfaces refers to a non-existent type declaration
1096 * @throws java.lang.reflect.MalformedParameterizedTypeException
1097 * if any of the generic superinterfaces refer to a parameterized
1098 * type that cannot be instantiated for any reason
1099 * @return an array of interfaces directly implemented by this class
1100 * @since 1.5
1101 */
1102 public Type[] getGenericInterfaces() {
1103 ClassRepository info = getGenericInfo();
1104 return (info == null) ? getInterfaces() : info.getSuperInterfaces();
1105 }
1106
1107
1108 /**
1109 * Returns the {@code Class} representing the component type of an
1110 * array. If this class does not represent an array class this method
1111 * returns null.
1112 *
1113 * @return the {@code Class} representing the component type of this
1114 * class if this class is an array
1115 * @see java.lang.reflect.Array
1116 * @since 1.1
1117 */
1118 public Class<?> getComponentType() {
1119 // Only return for array types. Storage may be reused for Class for instance types.
1120 if (isArray()) {
1121 return componentType;
1122 } else {
1123 return null;
1124 }
1125 }
1126
1127 private final Class<?> componentType;
1128
1129
1130 /**
1131 * Returns the Java language modifiers for this class or interface, encoded
1132 * in an integer. The modifiers consist of the Java Virtual Machine's
1133 * constants for {@code public}, {@code protected},
1134 * {@code private}, {@code final}, {@code static},
1135 * {@code abstract} and {@code interface}; they should be decoded
1136 * using the methods of class {@code Modifier}.
1137 *
1138 * <p> If the underlying class is an array class, then its
1139 * {@code public}, {@code private} and {@code protected}
1140 * modifiers are the same as those of its component type. If this
1141 * {@code Class} represents a primitive type or void, its
1142 * {@code public} modifier is always {@code true}, and its
1143 * {@code protected} and {@code private} modifiers are always
1144 * {@code false}. If this object represents an array class, a
1145 * primitive type or void, then its {@code final} modifier is always
1146 * {@code true} and its interface modifier is always
1147 * {@code false}. The values of its other modifiers are not determined
1148 * by this specification.
1149 *
1150 * <p> The modifier encodings are defined in <em>The Java Virtual Machine
1151 * Specification</em>, table 4.1.
1152 *
1153 * @return the {@code int} representing the modifiers for this class
1154 * @see java.lang.reflect.Modifier
1155 * @since 1.1
1156 */
1157 @HotSpotIntrinsicCandidate
1158 public native int getModifiers();
1159
1160
1161 /**
1162 * Gets the signers of this class.
1163 *
1164 * @return the signers of this class, or null if there are no signers. In
1165 * particular, this method returns null if this object represents
1166 * a primitive type or void.
1167 * @since 1.1
1168 */
1169 public native Object[] getSigners();
1170
1171
1172 /**
1173 * Set the signers of this class.
1174 */
1175 native void setSigners(Object[] signers);
1176
1177
1178 /**
1179 * If this {@code Class} object represents a local or anonymous
1180 * class within a method, returns a {@link
1181 * java.lang.reflect.Method Method} object representing the
1182 * immediately enclosing method of the underlying class. Returns
1183 * {@code null} otherwise.
1184 *
1185 * In particular, this method returns {@code null} if the underlying
1186 * class is a local or anonymous class immediately enclosed by a type
1187 * declaration, instance initializer or static initializer.
1188 *
1189 * @return the immediately enclosing method of the underlying class, if
1190 * that class is a local or anonymous class; otherwise {@code null}.
1191 *
1192 * @throws SecurityException
1193 * If a security manager, <i>s</i>, is present and any of the
1194 * following conditions is met:
1195 *
1196 * <ul>
1197 *
1198 * <li> the caller's class loader is not the same as the
1199 * class loader of the enclosing class and invocation of
1200 * {@link SecurityManager#checkPermission
1201 * s.checkPermission} method with
1202 * {@code RuntimePermission("accessDeclaredMembers")}
1203 * denies access to the methods within the enclosing class
1204 *
1205 * <li> the caller's class loader is not the same as or an
1206 * ancestor of the class loader for the enclosing class and
1207 * invocation of {@link SecurityManager#checkPackageAccess
1208 * s.checkPackageAccess()} denies access to the package
1209 * of the enclosing class
1210 *
1211 * </ul>
1212 * @since 1.5
1213 */
1214 @CallerSensitive
1215 public Method getEnclosingMethod() throws SecurityException {
1216 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1217
1218 if (enclosingInfo == null)
1219 return null;
1220 else {
1221 if (!enclosingInfo.isMethod())
1222 return null;
1223
1224 MethodRepository typeInfo = MethodRepository.make(enclosingInfo.getDescriptor(),
1225 getFactory());
1226 Class<?> returnType = toClass(typeInfo.getReturnType());
1227 Type [] parameterTypes = typeInfo.getParameterTypes();
1228 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length];
1229
1230 // Convert Types to Classes; returned types *should*
1231 // be class objects since the methodDescriptor's used
1232 // don't have generics information
1233 for(int i = 0; i < parameterClasses.length; i++)
1234 parameterClasses[i] = toClass(parameterTypes[i]);
1235
1236 // Perform access check
1237 final Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass();
1238 enclosingCandidate.checkMemberAccess(Member.DECLARED,
1239 Reflection.getCallerClass(), true);
1240 // Client is ok to access declared methods but j.l.Class might not be.
1241 Method[] candidates = AccessController.doPrivileged(
1242 new PrivilegedAction<>() {
1243 @Override
1244 public Method[] run() {
1245 return enclosingCandidate.getDeclaredMethods();
1246 }
1247 });
1248 /*
1249 * Loop over all declared methods; match method name,
1250 * number of and type of parameters, *and* return
1251 * type. Matching return type is also necessary
1252 * because of covariant returns, etc.
1253 */
1254 for(Method m: candidates) {
1255 if (m.getName().equals(enclosingInfo.getName()) ) {
1256 Class<?>[] candidateParamClasses = m.getParameterTypes();
1257 if (candidateParamClasses.length == parameterClasses.length) {
1258 boolean matches = true;
1259 for(int i = 0; i < candidateParamClasses.length; i++) {
1260 if (!candidateParamClasses[i].equals(parameterClasses[i])) {
1261 matches = false;
1262 break;
1263 }
1264 }
1265
1266 if (matches) { // finally, check return type
1267 if (m.getReturnType().equals(returnType) )
1268 return m;
1269 }
1270 }
1271 }
1272 }
1273
1274 throw new InternalError("Enclosing method not found");
1275 }
1276 }
1277
1278 private native Object[] getEnclosingMethod0();
1279
1280 private EnclosingMethodInfo getEnclosingMethodInfo() {
1281 Object[] enclosingInfo = getEnclosingMethod0();
1282 if (enclosingInfo == null)
1283 return null;
1284 else {
1285 return new EnclosingMethodInfo(enclosingInfo);
1286 }
1287 }
1288
1289 private static final class EnclosingMethodInfo {
1290 private Class<?> enclosingClass;
1291 private String name;
1292 private String descriptor;
1293
1294 private EnclosingMethodInfo(Object[] enclosingInfo) {
1295 if (enclosingInfo.length != 3)
1296 throw new InternalError("Malformed enclosing method information");
1297 try {
1298 // The array is expected to have three elements:
1299
1300 // the immediately enclosing class
1301 enclosingClass = (Class<?>) enclosingInfo[0];
1302 assert(enclosingClass != null);
1303
1304 // the immediately enclosing method or constructor's
1305 // name (can be null).
1306 name = (String) enclosingInfo[1];
1307
1308 // the immediately enclosing method or constructor's
1309 // descriptor (null iff name is).
1310 descriptor = (String) enclosingInfo[2];
1311 assert((name != null && descriptor != null) || name == descriptor);
1312 } catch (ClassCastException cce) {
1313 throw new InternalError("Invalid type in enclosing method information", cce);
1314 }
1315 }
1316
1317 boolean isPartial() {
1318 return enclosingClass == null || name == null || descriptor == null;
1319 }
1320
1321 boolean isConstructor() { return !isPartial() && "<init>".equals(name); }
1322
1323 boolean isMethod() { return !isPartial() && !isConstructor() && !"<clinit>".equals(name); }
1324
1325 Class<?> getEnclosingClass() { return enclosingClass; }
1326
1327 String getName() { return name; }
1328
1329 String getDescriptor() { return descriptor; }
1330
1331 }
1332
1333 private static Class<?> toClass(Type o) {
1334 if (o instanceof GenericArrayType)
1335 return Array.newInstance(toClass(((GenericArrayType)o).getGenericComponentType()),
1336 0)
1337 .getClass();
1338 return (Class<?>)o;
1339 }
1340
1341 /**
1342 * If this {@code Class} object represents a local or anonymous
1343 * class within a constructor, returns a {@link
1344 * java.lang.reflect.Constructor Constructor} object representing
1345 * the immediately enclosing constructor of the underlying
1346 * class. Returns {@code null} otherwise. In particular, this
1347 * method returns {@code null} if the underlying class is a local
1348 * or anonymous class immediately enclosed by a type declaration,
1349 * instance initializer or static initializer.
1350 *
1351 * @return the immediately enclosing constructor of the underlying class, if
1352 * that class is a local or anonymous class; otherwise {@code null}.
1353 * @throws SecurityException
1354 * If a security manager, <i>s</i>, is present and any of the
1355 * following conditions is met:
1356 *
1357 * <ul>
1358 *
1359 * <li> the caller's class loader is not the same as the
1360 * class loader of the enclosing class and invocation of
1361 * {@link SecurityManager#checkPermission
1362 * s.checkPermission} method with
1363 * {@code RuntimePermission("accessDeclaredMembers")}
1364 * denies access to the constructors within the enclosing class
1365 *
1366 * <li> the caller's class loader is not the same as or an
1367 * ancestor of the class loader for the enclosing class and
1368 * invocation of {@link SecurityManager#checkPackageAccess
1369 * s.checkPackageAccess()} denies access to the package
1370 * of the enclosing class
1371 *
1372 * </ul>
1373 * @since 1.5
1374 */
1375 @CallerSensitive
1376 public Constructor<?> getEnclosingConstructor() throws SecurityException {
1377 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1378
1379 if (enclosingInfo == null)
1380 return null;
1381 else {
1382 if (!enclosingInfo.isConstructor())
1383 return null;
1384
1385 ConstructorRepository typeInfo = ConstructorRepository.make(enclosingInfo.getDescriptor(),
1386 getFactory());
1387 Type [] parameterTypes = typeInfo.getParameterTypes();
1388 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length];
1389
1390 // Convert Types to Classes; returned types *should*
1391 // be class objects since the methodDescriptor's used
1392 // don't have generics information
1393 for(int i = 0; i < parameterClasses.length; i++)
1394 parameterClasses[i] = toClass(parameterTypes[i]);
1395
1396 // Perform access check
1397 final Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass();
1398 enclosingCandidate.checkMemberAccess(Member.DECLARED,
1399 Reflection.getCallerClass(), true);
1400 // Client is ok to access declared methods but j.l.Class might not be.
1401 Constructor<?>[] candidates = AccessController.doPrivileged(
1402 new PrivilegedAction<>() {
1403 @Override
1404 public Constructor<?>[] run() {
1405 return enclosingCandidate.getDeclaredConstructors();
1406 }
1407 });
1408 /*
1409 * Loop over all declared constructors; match number
1410 * of and type of parameters.
1411 */
1412 for(Constructor<?> c: candidates) {
1413 Class<?>[] candidateParamClasses = c.getParameterTypes();
1414 if (candidateParamClasses.length == parameterClasses.length) {
1415 boolean matches = true;
1416 for(int i = 0; i < candidateParamClasses.length; i++) {
1417 if (!candidateParamClasses[i].equals(parameterClasses[i])) {
1418 matches = false;
1419 break;
1420 }
1421 }
1422
1423 if (matches)
1424 return c;
1425 }
1426 }
1427
1428 throw new InternalError("Enclosing constructor not found");
1429 }
1430 }
1431
1432
1433 /**
1434 * If the class or interface represented by this {@code Class} object
1435 * is a member of another class, returns the {@code Class} object
1436 * representing the class in which it was declared. This method returns
1437 * null if this class or interface is not a member of any other class. If
1438 * this {@code Class} object represents an array class, a primitive
1439 * type, or void,then this method returns null.
1440 *
1441 * @return the declaring class for this class
1442 * @throws SecurityException
1443 * If a security manager, <i>s</i>, is present and the caller's
1444 * class loader is not the same as or an ancestor of the class
1445 * loader for the declaring class and invocation of {@link
1446 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
1447 * denies access to the package of the declaring class
1448 * @since 1.1
1449 */
1450 @CallerSensitive
1451 public Class<?> getDeclaringClass() throws SecurityException {
1452 final Class<?> candidate = getDeclaringClass0();
1453
1454 if (candidate != null)
1455 candidate.checkPackageAccess(
1456 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
1457 return candidate;
1458 }
1459
1460 private native Class<?> getDeclaringClass0();
1461
1462
1463 /**
1464 * Returns the immediately enclosing class of the underlying
1465 * class. If the underlying class is a top level class this
1466 * method returns {@code null}.
1467 * @return the immediately enclosing class of the underlying class
1468 * @exception SecurityException
1469 * If a security manager, <i>s</i>, is present and the caller's
1470 * class loader is not the same as or an ancestor of the class
1471 * loader for the enclosing class and invocation of {@link
1472 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
1473 * denies access to the package of the enclosing class
1474 * @since 1.5
1475 */
1476 @CallerSensitive
1477 public Class<?> getEnclosingClass() throws SecurityException {
1478 // There are five kinds of classes (or interfaces):
1479 // a) Top level classes
1480 // b) Nested classes (static member classes)
1481 // c) Inner classes (non-static member classes)
1482 // d) Local classes (named classes declared within a method)
1483 // e) Anonymous classes
1484
1485
1486 // JVM Spec 4.7.7: A class must have an EnclosingMethod
1487 // attribute if and only if it is a local class or an
1488 // anonymous class.
1489 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1490 Class<?> enclosingCandidate;
1491
1492 if (enclosingInfo == null) {
1493 // This is a top level or a nested class or an inner class (a, b, or c)
1494 enclosingCandidate = getDeclaringClass();
1495 } else {
1496 Class<?> enclosingClass = enclosingInfo.getEnclosingClass();
1497 // This is a local class or an anonymous class (d or e)
1498 if (enclosingClass == this || enclosingClass == null)
1499 throw new InternalError("Malformed enclosing method information");
1500 else
1501 enclosingCandidate = enclosingClass;
1502 }
1503
1504 if (enclosingCandidate != null)
1505 enclosingCandidate.checkPackageAccess(
1506 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
1507 return enclosingCandidate;
1508 }
1509
1510 /**
1511 * Returns the simple name of the underlying class as given in the
1512 * source code. Returns an empty string if the underlying class is
1513 * anonymous.
1514 *
1515 * <p>The simple name of an array is the simple name of the
1516 * component type with "[]" appended. In particular the simple
1517 * name of an array whose component type is anonymous is "[]".
1518 *
1519 * @return the simple name of the underlying class
1520 * @since 1.5
1521 */
1522 public String getSimpleName() {
1523 if (isArray())
1524 return getComponentType().getSimpleName()+"[]";
1525
1526 String simpleName = getSimpleBinaryName();
1527 if (simpleName == null) { // top level class
1528 simpleName = getName();
1529 return simpleName.substring(simpleName.lastIndexOf('.')+1); // strip the package name
1530 }
1531 return simpleName;
1532 }
1533
1534 /**
1535 * Return an informative string for the name of this type.
1536 *
1537 * @return an informative string for the name of this type
1538 * @since 1.8
1539 */
1540 public String getTypeName() {
1541 if (isArray()) {
1542 try {
1543 Class<?> cl = this;
1544 int dimensions = 0;
1545 while (cl.isArray()) {
1546 dimensions++;
1547 cl = cl.getComponentType();
1548 }
1549 StringBuilder sb = new StringBuilder();
1550 sb.append(cl.getName());
1551 for (int i = 0; i < dimensions; i++) {
1552 sb.append("[]");
1553 }
1554 return sb.toString();
1555 } catch (Throwable e) { /*FALLTHRU*/ }
1556 }
1557 return getName();
1558 }
1559
1560 /**
1561 * Character.isDigit answers {@code true} to some non-ascii
1562 * digits. This one does not.
1563 */
1564 private static boolean isAsciiDigit(char c) {
1565 return '0' <= c && c <= '9';
1566 }
1567
1568 /**
1569 * Returns the canonical name of the underlying class as
1570 * defined by the Java Language Specification. Returns null if
1571 * the underlying class does not have a canonical name (i.e., if
1572 * it is a local or anonymous class or an array whose component
1573 * type does not have a canonical name).
1574 * @return the canonical name of the underlying class if it exists, and
1575 * {@code null} otherwise.
1576 * @since 1.5
1577 */
1578 public String getCanonicalName() {
1579 if (isArray()) {
1580 String canonicalName = getComponentType().getCanonicalName();
1581 if (canonicalName != null)
1582 return canonicalName + "[]";
1583 else
1584 return null;
1585 }
1586 if (isLocalOrAnonymousClass())
1587 return null;
1588 Class<?> enclosingClass = getEnclosingClass();
1589 if (enclosingClass == null) { // top level class
1590 return getName();
1591 } else {
1592 String enclosingName = enclosingClass.getCanonicalName();
1593 if (enclosingName == null)
1594 return null;
1595 return enclosingName + "." + getSimpleName();
1596 }
1597 }
1598
1599 /**
1600 * Returns {@code true} if and only if the underlying class
1601 * is an anonymous class.
1602 *
1603 * @return {@code true} if and only if this class is an anonymous class.
1604 * @since 1.5
1605 */
1606 public boolean isAnonymousClass() {
1607 return "".equals(getSimpleName());
1608 }
1609
1610 /**
1611 * Returns {@code true} if and only if the underlying class
1612 * is a local class.
1613 *
1614 * @return {@code true} if and only if this class is a local class.
1615 * @since 1.5
1616 */
1617 public boolean isLocalClass() {
1618 return isLocalOrAnonymousClass() && !isAnonymousClass();
1619 }
1620
1621 /**
1622 * Returns {@code true} if and only if the underlying class
1623 * is a member class.
1624 *
1625 * @return {@code true} if and only if this class is a member class.
1626 * @since 1.5
1627 */
1628 public boolean isMemberClass() {
1629 return getSimpleBinaryName() != null && !isLocalOrAnonymousClass();
1630 }
1631
1632 /**
1633 * Returns the "simple binary name" of the underlying class, i.e.,
1634 * the binary name without the leading enclosing class name.
1635 * Returns {@code null} if the underlying class is a top level
1636 * class.
1637 */
1638 private String getSimpleBinaryName() {
1639 Class<?> enclosingClass = getEnclosingClass();
1640 if (enclosingClass == null) // top level class
1641 return null;
1642 String name = getSimpleBinaryName0();
1643 if (name == null) // anonymous class
1644 return "";
1645 return name;
1646 }
1647
1648 private native String getSimpleBinaryName0();
1649
1650 /**
1651 * Returns {@code true} if this is a local class or an anonymous
1652 * class. Returns {@code false} otherwise.
1653 */
1654 private boolean isLocalOrAnonymousClass() {
1655 // JVM Spec 4.7.7: A class must have an EnclosingMethod
1656 // attribute if and only if it is a local class or an
1657 // anonymous class.
1658 return getEnclosingMethodInfo() != null;
1659 }
1660
1661 /**
1662 * Returns an array containing {@code Class} objects representing all
1663 * the public classes and interfaces that are members of the class
1664 * represented by this {@code Class} object. This includes public
1665 * class and interface members inherited from superclasses and public class
1666 * and interface members declared by the class. This method returns an
1667 * array of length 0 if this {@code Class} object has no public member
1668 * classes or interfaces. This method also returns an array of length 0 if
1669 * this {@code Class} object represents a primitive type, an array
1670 * class, or void.
1671 *
1672 * @return the array of {@code Class} objects representing the public
1673 * members of this class
1674 * @throws SecurityException
1675 * If a security manager, <i>s</i>, is present and
1676 * the caller's class loader is not the same as or an
1677 * ancestor of the class loader for the current class and
1678 * invocation of {@link SecurityManager#checkPackageAccess
1679 * s.checkPackageAccess()} denies access to the package
1680 * of this class.
1681 *
1682 * @since 1.1
1683 */
1684 @CallerSensitive
1685 public Class<?>[] getClasses() {
1686 checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), false);
1687
1688 // Privileged so this implementation can look at DECLARED classes,
1689 // something the caller might not have privilege to do. The code here
1690 // is allowed to look at DECLARED classes because (1) it does not hand
1691 // out anything other than public members and (2) public member access
1692 // has already been ok'd by the SecurityManager.
1693
1694 return java.security.AccessController.doPrivileged(
1695 new java.security.PrivilegedAction<>() {
1696 public Class<?>[] run() {
1697 List<Class<?>> list = new ArrayList<>();
1698 Class<?> currentClass = Class.this;
1699 while (currentClass != null) {
1700 for (Class<?> m : currentClass.getDeclaredClasses()) {
1701 if (Modifier.isPublic(m.getModifiers())) {
1702 list.add(m);
1703 }
1704 }
1705 currentClass = currentClass.getSuperclass();
1706 }
1707 return list.toArray(new Class<?>[0]);
1708 }
1709 });
1710 }
1711
1712
1713 /**
1714 * Returns an array containing {@code Field} objects reflecting all
1715 * the accessible public fields of the class or interface represented by
1716 * this {@code Class} object.
1717 *
1718 * <p> If this {@code Class} object represents a class or interface with
1719 * no accessible public fields, then this method returns an array of length
1720 * 0.
1721 *
1722 * <p> If this {@code Class} object represents a class, then this method
1723 * returns the public fields of the class and of all its superclasses and
1724 * superinterfaces.
1725 *
1726 * <p> If this {@code Class} object represents an interface, then this
1727 * method returns the fields of the interface and of all its
1728 * superinterfaces.
1729 *
1730 * <p> If this {@code Class} object represents an array type, a primitive
1731 * type, or void, then this method returns an array of length 0.
1732 *
1733 * <p> The elements in the returned array are not sorted and are not in any
1734 * particular order.
1735 *
1736 * @return the array of {@code Field} objects representing the
1737 * public fields
1738 * @throws SecurityException
1739 * If a security manager, <i>s</i>, is present and
1740 * the caller's class loader is not the same as or an
1741 * ancestor of the class loader for the current class and
1742 * invocation of {@link SecurityManager#checkPackageAccess
1743 * s.checkPackageAccess()} denies access to the package
1744 * of this class.
1745 *
1746 * @since 1.1
1747 * @jls 8.2 Class Members
1748 * @jls 8.3 Field Declarations
1749 */
1750 @CallerSensitive
1751 public Field[] getFields() throws SecurityException {
1752 checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true);
1753 return copyFields(privateGetPublicFields(null));
1754 }
1755
1756
1757 /**
1758 * Returns an array containing {@code Method} objects reflecting all the
1759 * public methods of the class or interface represented by this {@code
1760 * Class} object, including those declared by the class or interface and
1761 * those inherited from superclasses and superinterfaces.
1762 *
1763 * <p> If this {@code Class} object represents a type that has multiple
1764 * public methods with the same name and parameter types, but different
1765 * return types, then the returned array has a {@code Method} object for
1766 * each such method.
1767 *
1768 * <p> If this {@code Class} object represents a type with a class
1769 * initialization method {@code <clinit>}, then the returned array does
1770 * <em>not</em> have a corresponding {@code Method} object.
1771 *
1772 * <p> If this {@code Class} object represents an array type, then the
1773 * returned array has a {@code Method} object for each of the public
1774 * methods inherited by the array type from {@code Object}. It does not
1775 * contain a {@code Method} object for {@code clone()}.
1776 *
1777 * <p> If this {@code Class} object represents an interface then the
1778 * returned array does not contain any implicitly declared methods from
1779 * {@code Object}. Therefore, if no methods are explicitly declared in
1780 * this interface or any of its superinterfaces then the returned array
1781 * has length 0. (Note that a {@code Class} object which represents a class
1782 * always has public methods, inherited from {@code Object}.)
1783 *
1784 * <p> If this {@code Class} object represents a primitive type or void,
1785 * then the returned array has length 0.
1786 *
1787 * <p> Static methods declared in superinterfaces of the class or interface
1788 * represented by this {@code Class} object are not considered members of
1789 * the class or interface.
1790 *
1791 * <p> The elements in the returned array are not sorted and are not in any
1792 * particular order.
1793 *
1794 * @return the array of {@code Method} objects representing the
1795 * public methods of this class
1796 * @throws SecurityException
1797 * If a security manager, <i>s</i>, is present and
1798 * the caller's class loader is not the same as or an
1799 * ancestor of the class loader for the current class and
1800 * invocation of {@link SecurityManager#checkPackageAccess
1801 * s.checkPackageAccess()} denies access to the package
1802 * of this class.
1803 *
1804 * @jls 8.2 Class Members
1805 * @jls 8.4 Method Declarations
1806 * @since 1.1
1807 */
1808 @CallerSensitive
1809 public Method[] getMethods() throws SecurityException {
1810 checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true);
1811 return copyMethods(privateGetPublicMethods());
1812 }
1813
1814
1815 /**
1816 * Returns an array containing {@code Constructor} objects reflecting
1817 * all the public constructors of the class represented by this
1818 * {@code Class} object. An array of length 0 is returned if the
1819 * class has no public constructors, or if the class is an array class, or
1820 * if the class reflects a primitive type or void.
1821 *
1822 * Note that while this method returns an array of {@code
1823 * Constructor<T>} objects (that is an array of constructors from
1824 * this class), the return type of this method is {@code
1825 * Constructor<?>[]} and <em>not</em> {@code Constructor<T>[]} as
1826 * might be expected. This less informative return type is
1827 * necessary since after being returned from this method, the
1828 * array could be modified to hold {@code Constructor} objects for
1829 * different classes, which would violate the type guarantees of
1830 * {@code Constructor<T>[]}.
1831 *
1832 * @return the array of {@code Constructor} objects representing the
1833 * public constructors of this class
1834 * @throws SecurityException
1835 * If a security manager, <i>s</i>, is present and
1836 * the caller's class loader is not the same as or an
1837 * ancestor of the class loader for the current class and
1838 * invocation of {@link SecurityManager#checkPackageAccess
1839 * s.checkPackageAccess()} denies access to the package
1840 * of this class.
1841 *
1842 * @since 1.1
1843 */
1844 @CallerSensitive
1845 public Constructor<?>[] getConstructors() throws SecurityException {
1846 checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true);
1847 return copyConstructors(privateGetDeclaredConstructors(true));
1848 }
1849
1850
1851 /**
1852 * Returns a {@code Field} object that reflects the specified public member
1853 * field of the class or interface represented by this {@code Class}
1854 * object. The {@code name} parameter is a {@code String} specifying the
1855 * simple name of the desired field.
1856 *
1857 * <p> The field to be reflected is determined by the algorithm that
1858 * follows. Let C be the class or interface represented by this object:
1859 *
1860 * <OL>
1861 * <LI> If C declares a public field with the name specified, that is the
1862 * field to be reflected.</LI>
1863 * <LI> If no field was found in step 1 above, this algorithm is applied
1864 * recursively to each direct superinterface of C. The direct
1865 * superinterfaces are searched in the order they were declared.</LI>
1866 * <LI> If no field was found in steps 1 and 2 above, and C has a
1867 * superclass S, then this algorithm is invoked recursively upon S.
1868 * If C has no superclass, then a {@code NoSuchFieldException}
1869 * is thrown.</LI>
1870 * </OL>
1871 *
1872 * <p> If this {@code Class} object represents an array type, then this
1873 * method does not find the {@code length} field of the array type.
1874 *
1875 * @param name the field name
1876 * @return the {@code Field} object of this class specified by
1877 * {@code name}
1878 * @throws NoSuchFieldException if a field with the specified name is
1879 * not found.
1880 * @throws NullPointerException if {@code name} is {@code null}
1881 * @throws SecurityException
1882 * If a security manager, <i>s</i>, is present and
1883 * the caller's class loader is not the same as or an
1884 * ancestor of the class loader for the current class and
1885 * invocation of {@link SecurityManager#checkPackageAccess
1886 * s.checkPackageAccess()} denies access to the package
1887 * of this class.
1888 *
1889 * @since 1.1
1890 * @jls 8.2 Class Members
1891 * @jls 8.3 Field Declarations
1892 */
1893 @CallerSensitive
1894 public Field getField(String name)
1895 throws NoSuchFieldException, SecurityException {
1896 checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true);
1897 Field field = getField0(name);
1898 if (field == null) {
1899 throw new NoSuchFieldException(name);
1900 }
1901 return field;
1902 }
1903
1904
1905 /**
1906 * Returns a {@code Method} object that reflects the specified public
1907 * member method of the class or interface represented by this
1908 * {@code Class} object. The {@code name} parameter is a
1909 * {@code String} specifying the simple name of the desired method. The
1910 * {@code parameterTypes} parameter is an array of {@code Class}
1911 * objects that identify the method's formal parameter types, in declared
1912 * order. If {@code parameterTypes} is {@code null}, it is
1913 * treated as if it were an empty array.
1914 *
1915 * <p> If the {@code name} is "{@code <init>}" or "{@code <clinit>}" a
1916 * {@code NoSuchMethodException} is raised. Otherwise, the method to
1917 * be reflected is determined by the algorithm that follows. Let C be the
1918 * class or interface represented by this object:
1919 * <OL>
1920 * <LI> C is searched for a <I>matching method</I>, as defined below. If a
1921 * matching method is found, it is reflected.</LI>
1922 * <LI> If no matching method is found by step 1 then:
1923 * <OL TYPE="a">
1924 * <LI> If C is a class other than {@code Object}, then this algorithm is
1925 * invoked recursively on the superclass of C.</LI>
1926 * <LI> If C is the class {@code Object}, or if C is an interface, then
1927 * the superinterfaces of C (if any) are searched for a matching
1928 * method. If any such method is found, it is reflected.</LI>
1929 * </OL></LI>
1930 * </OL>
1931 *
1932 * <p> To find a matching method in a class or interface C: If C
1933 * declares exactly one public method with the specified name and exactly
1934 * the same formal parameter types, that is the method reflected. If more
1935 * than one such method is found in C, and one of these methods has a
1936 * return type that is more specific than any of the others, that method is
1937 * reflected; otherwise one of the methods is chosen arbitrarily.
1938 *
1939 * <p>Note that there may be more than one matching method in a
1940 * class because while the Java language forbids a class to
1941 * declare multiple methods with the same signature but different
1942 * return types, the Java virtual machine does not. This
1943 * increased flexibility in the virtual machine can be used to
1944 * implement various language features. For example, covariant
1945 * returns can be implemented with {@linkplain
1946 * java.lang.reflect.Method#isBridge bridge methods}; the bridge
1947 * method and the method being overridden would have the same
1948 * signature but different return types.
1949 *
1950 * <p> If this {@code Class} object represents an array type, then this
1951 * method does not find the {@code clone()} method.
1952 *
1953 * <p> Static methods declared in superinterfaces of the class or interface
1954 * represented by this {@code Class} object are not considered members of
1955 * the class or interface.
1956 *
1957 * @param name the name of the method
1958 * @param parameterTypes the list of parameters
1959 * @return the {@code Method} object that matches the specified
1960 * {@code name} and {@code parameterTypes}
1961 * @throws NoSuchMethodException if a matching method is not found
1962 * or if the name is "<init>"or "<clinit>".
1963 * @throws NullPointerException if {@code name} is {@code null}
1964 * @throws SecurityException
1965 * If a security manager, <i>s</i>, is present and
1966 * the caller's class loader is not the same as or an
1967 * ancestor of the class loader for the current class and
1968 * invocation of {@link SecurityManager#checkPackageAccess
1969 * s.checkPackageAccess()} denies access to the package
1970 * of this class.
1971 *
1972 * @jls 8.2 Class Members
1973 * @jls 8.4 Method Declarations
1974 * @since 1.1
1975 */
1976 @CallerSensitive
1977 public Method getMethod(String name, Class<?>... parameterTypes)
1978 throws NoSuchMethodException, SecurityException {
1979 checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true);
1980 Method method = getMethod0(name, parameterTypes, true);
1981 if (method == null) {
1982 throw new NoSuchMethodException(getName() + "." + name + argumentTypesToString(parameterTypes));
1983 }
1984 return method;
1985 }
1986
1987
1988 /**
1989 * Returns a {@code Constructor} object that reflects the specified
1990 * public constructor of the class represented by this {@code Class}
1991 * object. The {@code parameterTypes} parameter is an array of
1992 * {@code Class} objects that identify the constructor's formal
1993 * parameter types, in declared order.
1994 *
1995 * If this {@code Class} object represents an inner class
1996 * declared in a non-static context, the formal parameter types
1997 * include the explicit enclosing instance as the first parameter.
1998 *
1999 * <p> The constructor to reflect is the public constructor of the class
2000 * represented by this {@code Class} object whose formal parameter
2001 * types match those specified by {@code parameterTypes}.
2002 *
2003 * @param parameterTypes the parameter array
2004 * @return the {@code Constructor} object of the public constructor that
2005 * matches the specified {@code parameterTypes}
2006 * @throws NoSuchMethodException if a matching method is not found.
2007 * @throws SecurityException
2008 * If a security manager, <i>s</i>, is present and
2009 * the caller's class loader is not the same as or an
2010 * ancestor of the class loader for the current class and
2011 * invocation of {@link SecurityManager#checkPackageAccess
2012 * s.checkPackageAccess()} denies access to the package
2013 * of this class.
2014 *
2015 * @since 1.1
2016 */
2017 @CallerSensitive
2018 public Constructor<T> getConstructor(Class<?>... parameterTypes)
2019 throws NoSuchMethodException, SecurityException {
2020 checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true);
2021 return getConstructor0(parameterTypes, Member.PUBLIC);
2022 }
2023
2024
2025 /**
2026 * Returns an array of {@code Class} objects reflecting all the
2027 * classes and interfaces declared as members of the class represented by
2028 * this {@code Class} object. This includes public, protected, default
2029 * (package) access, and private classes and interfaces declared by the
2030 * class, but excludes inherited classes and interfaces. This method
2031 * returns an array of length 0 if the class declares no classes or
2032 * interfaces as members, or if this {@code Class} object represents a
2033 * primitive type, an array class, or void.
2034 *
2035 * @return the array of {@code Class} objects representing all the
2036 * declared members of this class
2037 * @throws SecurityException
2038 * If a security manager, <i>s</i>, is present and any of the
2039 * following conditions is met:
2040 *
2041 * <ul>
2042 *
2043 * <li> the caller's class loader is not the same as the
2044 * class loader of this class and invocation of
2045 * {@link SecurityManager#checkPermission
2046 * s.checkPermission} method with
2047 * {@code RuntimePermission("accessDeclaredMembers")}
2048 * denies access to the declared classes within this class
2049 *
2050 * <li> the caller's class loader is not the same as or an
2051 * ancestor of the class loader for the current class and
2052 * invocation of {@link SecurityManager#checkPackageAccess
2053 * s.checkPackageAccess()} denies access to the package
2054 * of this class
2055 *
2056 * </ul>
2057 *
2058 * @since 1.1
2059 */
2060 @CallerSensitive
2061 public Class<?>[] getDeclaredClasses() throws SecurityException {
2062 checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), false);
2063 return getDeclaredClasses0();
2064 }
2065
2066
2067 /**
2068 * Returns an array of {@code Field} objects reflecting all the fields
2069 * declared by the class or interface represented by this
2070 * {@code Class} object. This includes public, protected, default
2071 * (package) access, and private fields, but excludes inherited fields.
2072 *
2073 * <p> If this {@code Class} object represents a class or interface with no
2074 * declared fields, then this method returns an array of length 0.
2075 *
2076 * <p> If this {@code Class} object represents an array type, a primitive
2077 * type, or void, then this method returns an array of length 0.
2078 *
2079 * <p> The elements in the returned array are not sorted and are not in any
2080 * particular order.
2081 *
2082 * @return the array of {@code Field} objects representing all the
2083 * declared fields of this class
2084 * @throws SecurityException
2085 * If a security manager, <i>s</i>, is present and any of the
2086 * following conditions is met:
2087 *
2088 * <ul>
2089 *
2090 * <li> the caller's class loader is not the same as the
2091 * class loader of this class and invocation of
2092 * {@link SecurityManager#checkPermission
2093 * s.checkPermission} method with
2094 * {@code RuntimePermission("accessDeclaredMembers")}
2095 * denies access to the declared fields within this class
2096 *
2097 * <li> the caller's class loader is not the same as or an
2098 * ancestor of the class loader for the current class and
2099 * invocation of {@link SecurityManager#checkPackageAccess
2100 * s.checkPackageAccess()} denies access to the package
2101 * of this class
2102 *
2103 * </ul>
2104 *
2105 * @since 1.1
2106 * @jls 8.2 Class Members
2107 * @jls 8.3 Field Declarations
2108 */
2109 @CallerSensitive
2110 public Field[] getDeclaredFields() throws SecurityException {
2111 checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true);
2112 return copyFields(privateGetDeclaredFields(false));
2113 }
2114
2115
2116 /**
2117 *
2118 * Returns an array containing {@code Method} objects reflecting all the
2119 * declared methods of the class or interface represented by this {@code
2120 * Class} object, including public, protected, default (package)
2121 * access, and private methods, but excluding inherited methods.
2122 *
2123 * <p> If this {@code Class} object represents a type that has multiple
2124 * declared methods with the same name and parameter types, but different
2125 * return types, then the returned array has a {@code Method} object for
2126 * each such method.
2127 *
2128 * <p> If this {@code Class} object represents a type that has a class
2129 * initialization method {@code <clinit>}, then the returned array does
2130 * <em>not</em> have a corresponding {@code Method} object.
2131 *
2132 * <p> If this {@code Class} object represents a class or interface with no
2133 * declared methods, then the returned array has length 0.
2134 *
2135 * <p> If this {@code Class} object represents an array type, a primitive
2136 * type, or void, then the returned array has length 0.
2137 *
2138 * <p> The elements in the returned array are not sorted and are not in any
2139 * particular order.
2140 *
2141 * @return the array of {@code Method} objects representing all the
2142 * declared methods of this class
2143 * @throws SecurityException
2144 * If a security manager, <i>s</i>, is present and any of the
2145 * following conditions is met:
2146 *
2147 * <ul>
2148 *
2149 * <li> the caller's class loader is not the same as the
2150 * class loader of this class and invocation of
2151 * {@link SecurityManager#checkPermission
2152 * s.checkPermission} method with
2153 * {@code RuntimePermission("accessDeclaredMembers")}
2154 * denies access to the declared methods within this class
2155 *
2156 * <li> the caller's class loader is not the same as or an
2157 * ancestor of the class loader for the current class and
2158 * invocation of {@link SecurityManager#checkPackageAccess
2159 * s.checkPackageAccess()} denies access to the package
2160 * of this class
2161 *
2162 * </ul>
2163 *
2164 * @jls 8.2 Class Members
2165 * @jls 8.4 Method Declarations
2166 * @since 1.1
2167 */
2168 @CallerSensitive
2169 public Method[] getDeclaredMethods() throws SecurityException {
2170 checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true);
2171 return copyMethods(privateGetDeclaredMethods(false));
2172 }
2173
2174
2175 /**
2176 * Returns an array of {@code Constructor} objects reflecting all the
2177 * constructors declared by the class represented by this
2178 * {@code Class} object. These are public, protected, default
2179 * (package) access, and private constructors. The elements in the array
2180 * returned are not sorted and are not in any particular order. If the
2181 * class has a default constructor, it is included in the returned array.
2182 * This method returns an array of length 0 if this {@code Class}
2183 * object represents an interface, a primitive type, an array class, or
2184 * void.
2185 *
2186 * <p> See <em>The Java Language Specification</em>, section 8.2.
2187 *
2188 * @return the array of {@code Constructor} objects representing all the
2189 * declared constructors of this class
2190 * @throws SecurityException
2191 * If a security manager, <i>s</i>, is present and any of the
2192 * following conditions is met:
2193 *
2194 * <ul>
2195 *
2196 * <li> the caller's class loader is not the same as the
2197 * class loader of this class and invocation of
2198 * {@link SecurityManager#checkPermission
2199 * s.checkPermission} method with
2200 * {@code RuntimePermission("accessDeclaredMembers")}
2201 * denies access to the declared constructors within this class
2202 *
2203 * <li> the caller's class loader is not the same as or an
2204 * ancestor of the class loader for the current class and
2205 * invocation of {@link SecurityManager#checkPackageAccess
2206 * s.checkPackageAccess()} denies access to the package
2207 * of this class
2208 *
2209 * </ul>
2210 *
2211 * @since 1.1
2212 */
2213 @CallerSensitive
2214 public Constructor<?>[] getDeclaredConstructors() throws SecurityException {
2215 checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true);
2216 return copyConstructors(privateGetDeclaredConstructors(false));
2217 }
2218
2219
2220 /**
2221 * Returns a {@code Field} object that reflects the specified declared
2222 * field of the class or interface represented by this {@code Class}
2223 * object. The {@code name} parameter is a {@code String} that specifies
2224 * the simple name of the desired field.
2225 *
2226 * <p> If this {@code Class} object represents an array type, then this
2227 * method does not find the {@code length} field of the array type.
2228 *
2229 * @param name the name of the field
2230 * @return the {@code Field} object for the specified field in this
2231 * class
2232 * @throws NoSuchFieldException if a field with the specified name is
2233 * not found.
2234 * @throws NullPointerException if {@code name} is {@code null}
2235 * @throws SecurityException
2236 * If a security manager, <i>s</i>, is present and any of the
2237 * following conditions is met:
2238 *
2239 * <ul>
2240 *
2241 * <li> the caller's class loader is not the same as the
2242 * class loader of this class and invocation of
2243 * {@link SecurityManager#checkPermission
2244 * s.checkPermission} method with
2245 * {@code RuntimePermission("accessDeclaredMembers")}
2246 * denies access to the declared field
2247 *
2248 * <li> the caller's class loader is not the same as or an
2249 * ancestor of the class loader for the current class and
2250 * invocation of {@link SecurityManager#checkPackageAccess
2251 * s.checkPackageAccess()} denies access to the package
2252 * of this class
2253 *
2254 * </ul>
2255 *
2256 * @since 1.1
2257 * @jls 8.2 Class Members
2258 * @jls 8.3 Field Declarations
2259 */
2260 @CallerSensitive
2261 public Field getDeclaredField(String name)
2262 throws NoSuchFieldException, SecurityException {
2263 checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true);
2264 Field field = searchFields(privateGetDeclaredFields(false), name);
2265 if (field == null) {
2266 throw new NoSuchFieldException(name);
2267 }
2268 return field;
2269 }
2270
2271
2272 /**
2273 * Returns a {@code Method} object that reflects the specified
2274 * declared method of the class or interface represented by this
2275 * {@code Class} object. The {@code name} parameter is a
2276 * {@code String} that specifies the simple name of the desired
2277 * method, and the {@code parameterTypes} parameter is an array of
2278 * {@code Class} objects that identify the method's formal parameter
2279 * types, in declared order. If more than one method with the same
2280 * parameter types is declared in a class, and one of these methods has a
2281 * return type that is more specific than any of the others, that method is
2282 * returned; otherwise one of the methods is chosen arbitrarily. If the
2283 * name is "<init>"or "<clinit>" a {@code NoSuchMethodException}
2284 * is raised.
2285 *
2286 * <p> If this {@code Class} object represents an array type, then this
2287 * method does not find the {@code clone()} method.
2288 *
2289 * @param name the name of the method
2290 * @param parameterTypes the parameter array
2291 * @return the {@code Method} object for the method of this class
2292 * matching the specified name and parameters
2293 * @throws NoSuchMethodException if a matching method is not found.
2294 * @throws NullPointerException if {@code name} is {@code null}
2295 * @throws SecurityException
2296 * If a security manager, <i>s</i>, is present and any of the
2297 * following conditions is met:
2298 *
2299 * <ul>
2300 *
2301 * <li> the caller's class loader is not the same as the
2302 * class loader of this class and invocation of
2303 * {@link SecurityManager#checkPermission
2304 * s.checkPermission} method with
2305 * {@code RuntimePermission("accessDeclaredMembers")}
2306 * denies access to the declared method
2307 *
2308 * <li> the caller's class loader is not the same as or an
2309 * ancestor of the class loader for the current class and
2310 * invocation of {@link SecurityManager#checkPackageAccess
2311 * s.checkPackageAccess()} denies access to the package
2312 * of this class
2313 *
2314 * </ul>
2315 *
2316 * @jls 8.2 Class Members
2317 * @jls 8.4 Method Declarations
2318 * @since 1.1
2319 */
2320 @CallerSensitive
2321 public Method getDeclaredMethod(String name, Class<?>... parameterTypes)
2322 throws NoSuchMethodException, SecurityException {
2323 checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true);
2324 Method method = searchMethods(privateGetDeclaredMethods(false), name, parameterTypes);
2325 if (method == null) {
2326 throw new NoSuchMethodException(getName() + "." + name + argumentTypesToString(parameterTypes));
2327 }
2328 return method;
2329 }
2330
2331
2332 /**
2333 * Returns a {@code Constructor} object that reflects the specified
2334 * constructor of the class or interface represented by this
2335 * {@code Class} object. The {@code parameterTypes} parameter is
2336 * an array of {@code Class} objects that identify the constructor's
2337 * formal parameter types, in declared order.
2338 *
2339 * If this {@code Class} object represents an inner class
2340 * declared in a non-static context, the formal parameter types
2341 * include the explicit enclosing instance as the first parameter.
2342 *
2343 * @param parameterTypes the parameter array
2344 * @return The {@code Constructor} object for the constructor with the
2345 * specified parameter list
2346 * @throws NoSuchMethodException if a matching method is not found.
2347 * @throws SecurityException
2348 * If a security manager, <i>s</i>, is present and any of the
2349 * following conditions is met:
2350 *
2351 * <ul>
2352 *
2353 * <li> the caller's class loader is not the same as the
2354 * class loader of this class and invocation of
2355 * {@link SecurityManager#checkPermission
2356 * s.checkPermission} method with
2357 * {@code RuntimePermission("accessDeclaredMembers")}
2358 * denies access to the declared constructor
2359 *
2360 * <li> the caller's class loader is not the same as or an
2361 * ancestor of the class loader for the current class and
2362 * invocation of {@link SecurityManager#checkPackageAccess
2363 * s.checkPackageAccess()} denies access to the package
2364 * of this class
2365 *
2366 * </ul>
2367 *
2368 * @since 1.1
2369 */
2370 @CallerSensitive
2371 public Constructor<T> getDeclaredConstructor(Class<?>... parameterTypes)
2372 throws NoSuchMethodException, SecurityException {
2373 checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true);
2374 return getConstructor0(parameterTypes, Member.DECLARED);
2375 }
2376
2377 /**
2378 * Finds a resource with a given name. If this class is in a named {@link
2379 * Module Module}, and the caller of this method is in the same module,
2380 * then this method will attempt to find the resource in that module.
2381 * Otherwise, the rules for searching resources
2382 * associated with a given class are implemented by the defining
2383 * {@linkplain ClassLoader class loader} of the class. This method
2384 * delegates to this object's class loader. If this object was loaded by
2385 * the bootstrap class loader, the method delegates to {@link
2386 * ClassLoader#getSystemResourceAsStream}.
2387 *
2388 * <p> Before finding a resource in the caller's module or delegation to a
2389 * class loader, an absolute resource name is constructed from the given
2390 * resource name using this algorithm:
2391 *
2392 * <ul>
2393 *
2394 * <li> If the {@code name} begins with a {@code '/'}
2395 * (<tt>'\u002f'</tt>), then the absolute name of the resource is the
2396 * portion of the {@code name} following the {@code '/'}.
2397 *
2398 * <li> Otherwise, the absolute name is of the following form:
2399 *
2400 * <blockquote>
2401 * {@code modified_package_name/name}
2402 * </blockquote>
2403 *
2404 * <p> Where the {@code modified_package_name} is the package name of this
2405 * object with {@code '/'} substituted for {@code '.'}
2406 * (<tt>'\u002e'</tt>).
2407 *
2408 * </ul>
2409 *
2410 * @param name name of the desired resource
2411 * @return A {@link java.io.InputStream} object or {@code null} if
2412 * no resource with this name is found
2413 * @throws NullPointerException If {@code name} is {@code null}
2414 * @since 1.1
2415 */
2416 @CallerSensitive
2417 public InputStream getResourceAsStream(String name) {
2418 name = resolveName(name);
2419
2420 // if this Class and the caller are in the same named module
2421 // then attempt to get an input stream to the resource in the
2422 // module
2423 Module module = getModule();
2424 if (module.isNamed()) {
2425 Class<?> caller = Reflection.getCallerClass();
2426 if (caller != null && caller.getModule() == module) {
2427 ClassLoader cl = getClassLoader0();
2428 String mn = module.getName();
2429 try {
2430
2431 // special-case built-in class loaders to avoid the
2432 // need for a URL connection
2433 if (cl == null) {
2434 return BootLoader.findResourceAsStream(mn, name);
2435 } else if (cl instanceof BuiltinClassLoader) {
2436 return ((BuiltinClassLoader) cl).findResourceAsStream(mn, name);
2437 } else {
2438 URL url = cl.findResource(mn, name);
2439 return (url != null) ? url.openStream() : null;
2440 }
2441
2442 } catch (IOException | SecurityException e) {
2443 return null;
2444 }
2445 }
2446 }
2447
2448 // this Class and caller not in the same named module
2449 ClassLoader cl = getClassLoader0();
2450 if (cl == null) {
2451 return ClassLoader.getSystemResourceAsStream(name);
2452 } else {
2453 return cl.getResourceAsStream(name);
2454 }
2455 }
2456
2457 /**
2458 * Finds a resource with a given name. If this class is in a named {@link
2459 * Module Module}, and the caller of this method is in the same module,
2460 * then this method will attempt to find the resource in that module.
2461 * Otherwise, the rules for searching resources
2462 * associated with a given class are implemented by the defining
2463 * {@linkplain ClassLoader class loader} of the class. This method
2464 * delegates to this object's class loader. If this object was loaded by
2465 * the bootstrap class loader, the method delegates to {@link
2466 * ClassLoader#getSystemResource}.
2467 *
2468 * <p> Before delegation, an absolute resource name is constructed from the
2469 * given resource name using this algorithm:
2470 *
2471 * <ul>
2472 *
2473 * <li> If the {@code name} begins with a {@code '/'}
2474 * (<tt>'\u002f'</tt>), then the absolute name of the resource is the
2475 * portion of the {@code name} following the {@code '/'}.
2476 *
2477 * <li> Otherwise, the absolute name is of the following form:
2478 *
2479 * <blockquote>
2480 * {@code modified_package_name/name}
2481 * </blockquote>
2482 *
2483 * <p> Where the {@code modified_package_name} is the package name of this
2484 * object with {@code '/'} substituted for {@code '.'}
2485 * (<tt>'\u002e'</tt>).
2486 *
2487 * </ul>
2488 *
2489 * @param name name of the desired resource
2490 * @return A {@link java.net.URL} object; {@code null} if no
2491 * resource with this name is found or the resource cannot
2492 * be located by a URL.
2493 * @since 1.1
2494 */
2495 @CallerSensitive
2496 public URL getResource(String name) {
2497 name = resolveName(name);
2498
2499 // if this Class and the caller are in the same named module
2500 // then attempt to get URL to the resource in the module
2501 Module module = getModule();
2502 if (module.isNamed()) {
2503 Class<?> caller = Reflection.getCallerClass();
2504 if (caller != null && caller.getModule() == module) {
2505 String mn = getModule().getName();
2506 ClassLoader cl = getClassLoader0();
2507 try {
2508 if (cl == null) {
2509 return BootLoader.findResource(mn, name);
2510 } else {
2511 return cl.findResource(mn, name);
2512 }
2513 } catch (IOException ioe) {
2514 return null;
2515 }
2516 }
2517 }
2518
2519 ClassLoader cl = getClassLoader0();
2520 if (cl == null) {
2521 return ClassLoader.getSystemResource(name);
2522 } else {
2523 return cl.getResource(name);
2524 }
2525 }
2526
2527 /** protection domain returned when the internal domain is null */
2528 private static java.security.ProtectionDomain allPermDomain;
2529
2530
2531 /**
2532 * Returns the {@code ProtectionDomain} of this class. If there is a
2533 * security manager installed, this method first calls the security
2534 * manager's {@code checkPermission} method with a
2535 * {@code RuntimePermission("getProtectionDomain")} permission to
2536 * ensure it's ok to get the
2537 * {@code ProtectionDomain}.
2538 *
2539 * @return the ProtectionDomain of this class
2540 *
2541 * @throws SecurityException
2542 * if a security manager exists and its
2543 * {@code checkPermission} method doesn't allow
2544 * getting the ProtectionDomain.
2545 *
2546 * @see java.security.ProtectionDomain
2547 * @see SecurityManager#checkPermission
2548 * @see java.lang.RuntimePermission
2549 * @since 1.2
2550 */
2551 public java.security.ProtectionDomain getProtectionDomain() {
2552 SecurityManager sm = System.getSecurityManager();
2553 if (sm != null) {
2554 sm.checkPermission(SecurityConstants.GET_PD_PERMISSION);
2555 }
2556 java.security.ProtectionDomain pd = getProtectionDomain0();
2557 if (pd == null) {
2558 if (allPermDomain == null) {
2559 java.security.Permissions perms =
2560 new java.security.Permissions();
2561 perms.add(SecurityConstants.ALL_PERMISSION);
2562 allPermDomain =
2563 new java.security.ProtectionDomain(null, perms);
2564 }
2565 pd = allPermDomain;
2566 }
2567 return pd;
2568 }
2569
2570
2571 /**
2572 * Returns the ProtectionDomain of this class.
2573 */
2574 private native java.security.ProtectionDomain getProtectionDomain0();
2575
2576 /*
2577 * Return the Virtual Machine's Class object for the named
2578 * primitive type.
2579 */
2580 static native Class<?> getPrimitiveClass(String name);
2581
2582 /*
2583 * Check if client is allowed to access members. If access is denied,
2584 * throw a SecurityException.
2585 *
2586 * This method also enforces package access.
2587 *
2588 * <p> Default policy: allow all clients access with normal Java access
2589 * control.
2590 */
2591 private void checkMemberAccess(int which, Class<?> caller, boolean checkProxyInterfaces) {
2592 final SecurityManager s = System.getSecurityManager();
2593 if (s != null) {
2594 /* Default policy allows access to all {@link Member#PUBLIC} members,
2595 * as well as access to classes that have the same class loader as the caller.
2596 * In all other cases, it requires RuntimePermission("accessDeclaredMembers")
2597 * permission.
2598 */
2599 final ClassLoader ccl = ClassLoader.getClassLoader(caller);
2600 final ClassLoader cl = getClassLoader0();
2601 if (which != Member.PUBLIC) {
2602 if (ccl != cl) {
2603 s.checkPermission(SecurityConstants.CHECK_MEMBER_ACCESS_PERMISSION);
2604 }
2605 }
2606 this.checkPackageAccess(ccl, checkProxyInterfaces);
2607 }
2608 }
2609
2610 /*
2611 * Checks if a client loaded in ClassLoader ccl is allowed to access this
2612 * class under the current package access policy. If access is denied,
2613 * throw a SecurityException.
2614 */
2615 private void checkPackageAccess(final ClassLoader ccl, boolean checkProxyInterfaces) {
2616 final SecurityManager s = System.getSecurityManager();
2617 if (s != null) {
2618 final ClassLoader cl = getClassLoader0();
2619
2620 if (ReflectUtil.needsPackageAccessCheck(ccl, cl)) {
2621 String name = this.getName();
2622 int i = name.lastIndexOf('.');
2623 if (i != -1) {
2624 // skip the package access check on a proxy class in default proxy package
2625 String pkg = name.substring(0, i);
2626 if (!Proxy.isProxyClass(this) || ReflectUtil.isNonPublicProxyClass(this)) {
2627 s.checkPackageAccess(pkg);
2628 }
2629 }
2630 }
2631 // check package access on the proxy interfaces
2632 if (checkProxyInterfaces && Proxy.isProxyClass(this)) {
2633 ReflectUtil.checkProxyPackageAccess(ccl, this.getInterfaces());
2634 }
2635 }
2636 }
2637
2638 /**
2639 * Add a package name prefix if the name is not absolute Remove leading "/"
2640 * if name is absolute
2641 */
2642 private String resolveName(String name) {
2643 if (name == null) {
2644 return name;
2645 }
2646 if (!name.startsWith("/")) {
2647 Class<?> c = this;
2648 while (c.isArray()) {
2649 c = c.getComponentType();
2650 }
2651 String baseName = c.getName();
2652 int index = baseName.lastIndexOf('.');
2653 if (index != -1) {
2654 name = baseName.substring(0, index).replace('.', '/')
2655 +"/"+name;
2656 }
2657 } else {
2658 name = name.substring(1);
2659 }
2660 return name;
2661 }
2662
2663 /**
2664 * Atomic operations support.
2665 */
2666 private static class Atomic {
2667 // initialize Unsafe machinery here, since we need to call Class.class instance method
2668 // and have to avoid calling it in the static initializer of the Class class...
2669 private static final Unsafe unsafe = Unsafe.getUnsafe();
2670 // offset of Class.reflectionData instance field
2671 private static final long reflectionDataOffset;
2672 // offset of Class.annotationType instance field
2673 private static final long annotationTypeOffset;
2674 // offset of Class.annotationData instance field
2675 private static final long annotationDataOffset;
2676
2677 static {
2678 Field[] fields = Class.class.getDeclaredFields0(false); // bypass caches
2679 reflectionDataOffset = objectFieldOffset(fields, "reflectionData");
2680 annotationTypeOffset = objectFieldOffset(fields, "annotationType");
2681 annotationDataOffset = objectFieldOffset(fields, "annotationData");
2682 }
2683
2684 private static long objectFieldOffset(Field[] fields, String fieldName) {
2685 Field field = searchFields(fields, fieldName);
2686 if (field == null) {
2687 throw new Error("No " + fieldName + " field found in java.lang.Class");
2688 }
2689 return unsafe.objectFieldOffset(field);
2690 }
2691
2692 static <T> boolean casReflectionData(Class<?> clazz,
2693 SoftReference<ReflectionData<T>> oldData,
2694 SoftReference<ReflectionData<T>> newData) {
2695 return unsafe.compareAndSwapObject(clazz, reflectionDataOffset, oldData, newData);
2696 }
2697
2698 static <T> boolean casAnnotationType(Class<?> clazz,
2699 AnnotationType oldType,
2700 AnnotationType newType) {
2701 return unsafe.compareAndSwapObject(clazz, annotationTypeOffset, oldType, newType);
2702 }
2703
2704 static <T> boolean casAnnotationData(Class<?> clazz,
2705 AnnotationData oldData,
2706 AnnotationData newData) {
2707 return unsafe.compareAndSwapObject(clazz, annotationDataOffset, oldData, newData);
2708 }
2709 }
2710
2711 /**
2712 * Reflection support.
2713 */
2714
2715 // Caches for certain reflective results
2716 private static boolean useCaches = true;
2717
2718 // reflection data that might get invalidated when JVM TI RedefineClasses() is called
2719 private static class ReflectionData<T> {
2720 volatile Field[] declaredFields;
2721 volatile Field[] publicFields;
2722 volatile Method[] declaredMethods;
2723 volatile Method[] publicMethods;
2724 volatile Constructor<T>[] declaredConstructors;
2725 volatile Constructor<T>[] publicConstructors;
2726 // Intermediate results for getFields and getMethods
2727 volatile Field[] declaredPublicFields;
2728 volatile Method[] declaredPublicMethods;
2729 volatile Class<?>[] interfaces;
2730
2731 // Value of classRedefinedCount when we created this ReflectionData instance
2732 final int redefinedCount;
2733
2734 ReflectionData(int redefinedCount) {
2735 this.redefinedCount = redefinedCount;
2736 }
2737 }
2738
2739 private transient volatile SoftReference<ReflectionData<T>> reflectionData;
2740
2741 // Incremented by the VM on each call to JVM TI RedefineClasses()
2742 // that redefines this class or a superclass.
2743 private transient volatile int classRedefinedCount;
2744
2745 // Lazily create and cache ReflectionData
2746 private ReflectionData<T> reflectionData() {
2747 SoftReference<ReflectionData<T>> reflectionData = this.reflectionData;
2748 int classRedefinedCount = this.classRedefinedCount;
2749 ReflectionData<T> rd;
2750 if (useCaches &&
2751 reflectionData != null &&
2752 (rd = reflectionData.get()) != null &&
2753 rd.redefinedCount == classRedefinedCount) {
2754 return rd;
2755 }
2756 // else no SoftReference or cleared SoftReference or stale ReflectionData
2757 // -> create and replace new instance
2758 return newReflectionData(reflectionData, classRedefinedCount);
2759 }
2760
2761 private ReflectionData<T> newReflectionData(SoftReference<ReflectionData<T>> oldReflectionData,
2762 int classRedefinedCount) {
2763 if (!useCaches) return null;
2764
2765 while (true) {
2766 ReflectionData<T> rd = new ReflectionData<>(classRedefinedCount);
2767 // try to CAS it...
2768 if (Atomic.casReflectionData(this, oldReflectionData, new SoftReference<>(rd))) {
2769 return rd;
2770 }
2771 // else retry
2772 oldReflectionData = this.reflectionData;
2773 classRedefinedCount = this.classRedefinedCount;
2774 if (oldReflectionData != null &&
2775 (rd = oldReflectionData.get()) != null &&
2776 rd.redefinedCount == classRedefinedCount) {
2777 return rd;
2778 }
2779 }
2780 }
2781
2782 // Generic signature handling
2783 private native String getGenericSignature0();
2784
2785 // Generic info repository; lazily initialized
2786 private transient volatile ClassRepository genericInfo;
2787
2788 // accessor for factory
2789 private GenericsFactory getFactory() {
2790 // create scope and factory
2791 return CoreReflectionFactory.make(this, ClassScope.make(this));
2792 }
2793
2794 // accessor for generic info repository;
2795 // generic info is lazily initialized
2796 private ClassRepository getGenericInfo() {
2797 ClassRepository genericInfo = this.genericInfo;
2798 if (genericInfo == null) {
2799 String signature = getGenericSignature0();
2800 if (signature == null) {
2801 genericInfo = ClassRepository.NONE;
2802 } else {
2803 genericInfo = ClassRepository.make(signature, getFactory());
2804 }
2805 this.genericInfo = genericInfo;
2806 }
2807 return (genericInfo != ClassRepository.NONE) ? genericInfo : null;
2808 }
2809
2810 // Annotations handling
2811 native byte[] getRawAnnotations();
2812 // Since 1.8
2813 native byte[] getRawTypeAnnotations();
2814 static byte[] getExecutableTypeAnnotationBytes(Executable ex) {
2815 return getReflectionFactory().getExecutableTypeAnnotationBytes(ex);
2816 }
2817
2818 native ConstantPool getConstantPool();
2819
2820 //
2821 //
2822 // java.lang.reflect.Field handling
2823 //
2824 //
2825
2826 // Returns an array of "root" fields. These Field objects must NOT
2827 // be propagated to the outside world, but must instead be copied
2828 // via ReflectionFactory.copyField.
2829 private Field[] privateGetDeclaredFields(boolean publicOnly) {
2830 checkInitted();
2831 Field[] res;
2832 ReflectionData<T> rd = reflectionData();
2833 if (rd != null) {
2834 res = publicOnly ? rd.declaredPublicFields : rd.declaredFields;
2835 if (res != null) return res;
2836 }
2837 // No cached value available; request value from VM
2838 res = Reflection.filterFields(this, getDeclaredFields0(publicOnly));
2839 if (rd != null) {
2840 if (publicOnly) {
2841 rd.declaredPublicFields = res;
2842 } else {
2843 rd.declaredFields = res;
2844 }
2845 }
2846 return res;
2847 }
2848
2849 // Returns an array of "root" fields. These Field objects must NOT
2850 // be propagated to the outside world, but must instead be copied
2851 // via ReflectionFactory.copyField.
2852 private Field[] privateGetPublicFields(Set<Class<?>> traversedInterfaces) {
2853 checkInitted();
2854 Field[] res;
2855 ReflectionData<T> rd = reflectionData();
2856 if (rd != null) {
2857 res = rd.publicFields;
2858 if (res != null) return res;
2859 }
2860
2861 // No cached value available; compute value recursively.
2862 // Traverse in correct order for getField().
2863 List<Field> fields = new ArrayList<>();
2864 if (traversedInterfaces == null) {
2865 traversedInterfaces = new HashSet<>();
2866 }
2867
2868 // Local fields
2869 Field[] tmp = privateGetDeclaredFields(true);
2870 addAll(fields, tmp);
2871
2872 // Direct superinterfaces, recursively
2873 for (Class<?> c : getInterfaces()) {
2874 if (!traversedInterfaces.contains(c)) {
2875 traversedInterfaces.add(c);
2876 addAll(fields, c.privateGetPublicFields(traversedInterfaces));
2877 }
2878 }
2879
2880 // Direct superclass, recursively
2881 if (!isInterface()) {
2882 Class<?> c = getSuperclass();
2883 if (c != null) {
2884 addAll(fields, c.privateGetPublicFields(traversedInterfaces));
2885 }
2886 }
2887
2888 res = new Field[fields.size()];
2889 fields.toArray(res);
2890 if (rd != null) {
2891 rd.publicFields = res;
2892 }
2893 return res;
2894 }
2895
2896 private static void addAll(Collection<Field> c, Field[] o) {
2897 for (Field f : o) {
2898 c.add(f);
2899 }
2900 }
2901
2902
2903 //
2904 //
2905 // java.lang.reflect.Constructor handling
2906 //
2907 //
2908
2909 // Returns an array of "root" constructors. These Constructor
2910 // objects must NOT be propagated to the outside world, but must
2911 // instead be copied via ReflectionFactory.copyConstructor.
2912 private Constructor<T>[] privateGetDeclaredConstructors(boolean publicOnly) {
2913 checkInitted();
2914 Constructor<T>[] res;
2915 ReflectionData<T> rd = reflectionData();
2916 if (rd != null) {
2917 res = publicOnly ? rd.publicConstructors : rd.declaredConstructors;
2918 if (res != null) return res;
2919 }
2920 // No cached value available; request value from VM
2921 if (isInterface()) {
2922 @SuppressWarnings("unchecked")
2923 Constructor<T>[] temporaryRes = (Constructor<T>[]) new Constructor<?>[0];
2924 res = temporaryRes;
2925 } else {
2926 res = getDeclaredConstructors0(publicOnly);
2927 }
2928 if (rd != null) {
2929 if (publicOnly) {
2930 rd.publicConstructors = res;
2931 } else {
2932 rd.declaredConstructors = res;
2933 }
2934 }
2935 return res;
2936 }
2937
2938 //
2939 //
2940 // java.lang.reflect.Method handling
2941 //
2942 //
2943
2944 // Returns an array of "root" methods. These Method objects must NOT
2945 // be propagated to the outside world, but must instead be copied
2946 // via ReflectionFactory.copyMethod.
2947 private Method[] privateGetDeclaredMethods(boolean publicOnly) {
2948 checkInitted();
2949 Method[] res;
2950 ReflectionData<T> rd = reflectionData();
2951 if (rd != null) {
2952 res = publicOnly ? rd.declaredPublicMethods : rd.declaredMethods;
2953 if (res != null) return res;
2954 }
2955 // No cached value available; request value from VM
2956 res = Reflection.filterMethods(this, getDeclaredMethods0(publicOnly));
2957 if (rd != null) {
2958 if (publicOnly) {
2959 rd.declaredPublicMethods = res;
2960 } else {
2961 rd.declaredMethods = res;
2962 }
2963 }
2964 return res;
2965 }
2966
2967 static class MethodArray {
2968 // Don't add or remove methods except by add() or remove() calls.
2969 private Method[] methods;
2970 private int length;
2971 private int defaults;
2972
2973 MethodArray() {
2974 this(20);
2975 }
2976
2977 MethodArray(int initialSize) {
2978 if (initialSize < 2)
2979 throw new IllegalArgumentException("Size should be 2 or more");
2980
2981 methods = new Method[initialSize];
2982 length = 0;
2983 defaults = 0;
2984 }
2985
2986 boolean hasDefaults() {
2987 return defaults != 0;
2988 }
2989
2990 void add(Method m) {
2991 if (length == methods.length) {
2992 methods = Arrays.copyOf(methods, 2 * methods.length);
2993 }
2994 methods[length++] = m;
2995
2996 if (m != null && m.isDefault())
2997 defaults++;
2998 }
2999
3000 void addAll(Method[] ma) {
3001 for (Method m : ma) {
3002 add(m);
3003 }
3004 }
3005
3006 void addAll(MethodArray ma) {
3007 for (int i = 0; i < ma.length(); i++) {
3008 add(ma.get(i));
3009 }
3010 }
3011
3012 void addIfNotPresent(Method newMethod) {
3013 for (int i = 0; i < length; i++) {
3014 Method m = methods[i];
3015 if (m == newMethod || (m != null && m.equals(newMethod))) {
3016 return;
3017 }
3018 }
3019 add(newMethod);
3020 }
3021
3022 void addAllIfNotPresent(MethodArray newMethods) {
3023 for (int i = 0; i < newMethods.length(); i++) {
3024 Method m = newMethods.get(i);
3025 if (m != null) {
3026 addIfNotPresent(m);
3027 }
3028 }
3029 }
3030
3031 /* Add Methods declared in an interface to this MethodArray.
3032 * Static methods declared in interfaces are not inherited.
3033 */
3034 void addInterfaceMethods(Method[] methods) {
3035 for (Method candidate : methods) {
3036 if (!Modifier.isStatic(candidate.getModifiers())) {
3037 add(candidate);
3038 }
3039 }
3040 }
3041
3042 int length() {
3043 return length;
3044 }
3045
3046 Method get(int i) {
3047 return methods[i];
3048 }
3049
3050 Method getFirst() {
3051 for (Method m : methods)
3052 if (m != null)
3053 return m;
3054 return null;
3055 }
3056
3057 void removeByNameAndDescriptor(Method toRemove) {
3058 for (int i = 0; i < length; i++) {
3059 Method m = methods[i];
3060 if (m != null && matchesNameAndDescriptor(m, toRemove)) {
3061 remove(i);
3062 }
3063 }
3064 }
3065
3066 private void remove(int i) {
3067 if (methods[i] != null && methods[i].isDefault())
3068 defaults--;
3069 methods[i] = null;
3070 }
3071
3072 private boolean matchesNameAndDescriptor(Method m1, Method m2) {
3073 return m1.getReturnType() == m2.getReturnType() &&
3074 m1.getName() == m2.getName() && // name is guaranteed to be interned
3075 arrayContentsEq(m1.getParameterTypes(),
3076 m2.getParameterTypes());
3077 }
3078
3079 void compactAndTrim() {
3080 int newPos = 0;
3081 // Get rid of null slots
3082 for (int pos = 0; pos < length; pos++) {
3083 Method m = methods[pos];
3084 if (m != null) {
3085 if (pos != newPos) {
3086 methods[newPos] = m;
3087 }
3088 newPos++;
3089 }
3090 }
3091 if (newPos != methods.length) {
3092 methods = Arrays.copyOf(methods, newPos);
3093 }
3094 }
3095
3096 /* Removes all Methods from this MethodArray that have a more specific
3097 * default Method in this MethodArray.
3098 *
3099 * Users of MethodArray are responsible for pruning Methods that have
3100 * a more specific <em>concrete</em> Method.
3101 */
3102 void removeLessSpecifics() {
3103 if (!hasDefaults())
3104 return;
3105
3106 for (int i = 0; i < length; i++) {
3107 Method m = get(i);
3108 if (m == null || !m.isDefault())
3109 continue;
3110
3111 for (int j = 0; j < length; j++) {
3112 if (i == j)
3113 continue;
3114
3115 Method candidate = get(j);
3116 if (candidate == null)
3117 continue;
3118
3119 if (!matchesNameAndDescriptor(m, candidate))
3120 continue;
3121
3122 if (hasMoreSpecificClass(m, candidate))
3123 remove(j);
3124 }
3125 }
3126 }
3127
3128 Method[] getArray() {
3129 return methods;
3130 }
3131
3132 // Returns true if m1 is more specific than m2
3133 static boolean hasMoreSpecificClass(Method m1, Method m2) {
3134 Class<?> m1Class = m1.getDeclaringClass();
3135 Class<?> m2Class = m2.getDeclaringClass();
3136 return m1Class != m2Class && m2Class.isAssignableFrom(m1Class);
3137 }
3138 }
3139
3140
3141 // Returns an array of "root" methods. These Method objects must NOT
3142 // be propagated to the outside world, but must instead be copied
3143 // via ReflectionFactory.copyMethod.
3144 private Method[] privateGetPublicMethods() {
3145 checkInitted();
3146 Method[] res;
3147 ReflectionData<T> rd = reflectionData();
3148 if (rd != null) {
3149 res = rd.publicMethods;
3150 if (res != null) return res;
3151 }
3152
3153 // No cached value available; compute value recursively.
3154 // Start by fetching public declared methods
3155 MethodArray methods = new MethodArray();
3156 {
3157 Method[] tmp = privateGetDeclaredMethods(true);
3158 methods.addAll(tmp);
3159 }
3160 // Now recur over superclass and direct superinterfaces.
3161 // Go over superinterfaces first so we can more easily filter
3162 // out concrete implementations inherited from superclasses at
3163 // the end.
3164 MethodArray inheritedMethods = new MethodArray();
3165 for (Class<?> i : getInterfaces()) {
3166 inheritedMethods.addInterfaceMethods(i.privateGetPublicMethods());
3167 }
3168 if (!isInterface()) {
3169 Class<?> c = getSuperclass();
3170 if (c != null) {
3171 MethodArray supers = new MethodArray();
3172 supers.addAll(c.privateGetPublicMethods());
3173 // Filter out concrete implementations of any
3174 // interface methods
3175 for (int i = 0; i < supers.length(); i++) {
3176 Method m = supers.get(i);
3177 if (m != null &&
3178 !Modifier.isAbstract(m.getModifiers()) &&
3179 !m.isDefault()) {
3180 inheritedMethods.removeByNameAndDescriptor(m);
3181 }
3182 }
3183 // Insert superclass's inherited methods before
3184 // superinterfaces' to satisfy getMethod's search
3185 // order
3186 supers.addAll(inheritedMethods);
3187 inheritedMethods = supers;
3188 }
3189 }
3190 // Filter out all local methods from inherited ones
3191 for (int i = 0; i < methods.length(); i++) {
3192 Method m = methods.get(i);
3193 inheritedMethods.removeByNameAndDescriptor(m);
3194 }
3195 methods.addAllIfNotPresent(inheritedMethods);
3196 methods.removeLessSpecifics();
3197 methods.compactAndTrim();
3198 res = methods.getArray();
3199 if (rd != null) {
3200 rd.publicMethods = res;
3201 }
3202 return res;
3203 }
3204
3205
3206 //
3207 // Helpers for fetchers of one field, method, or constructor
3208 //
3209
3210 private static Field searchFields(Field[] fields, String name) {
3211 String internedName = name.intern();
3212 for (Field field : fields) {
3213 if (field.getName() == internedName) {
3214 return getReflectionFactory().copyField(field);
3215 }
3216 }
3217 return null;
3218 }
3219
3220 private Field getField0(String name) throws NoSuchFieldException {
3221 // Note: the intent is that the search algorithm this routine
3222 // uses be equivalent to the ordering imposed by
3223 // privateGetPublicFields(). It fetches only the declared
3224 // public fields for each class, however, to reduce the number
3225 // of Field objects which have to be created for the common
3226 // case where the field being requested is declared in the
3227 // class which is being queried.
3228 Field res;
3229 // Search declared public fields
3230 if ((res = searchFields(privateGetDeclaredFields(true), name)) != null) {
3231 return res;
3232 }
3233 // Direct superinterfaces, recursively
3234 Class<?>[] interfaces = getInterfaces();
3235 for (Class<?> c : interfaces) {
3236 if ((res = c.getField0(name)) != null) {
3237 return res;
3238 }
3239 }
3240 // Direct superclass, recursively
3241 if (!isInterface()) {
3242 Class<?> c = getSuperclass();
3243 if (c != null) {
3244 if ((res = c.getField0(name)) != null) {
3245 return res;
3246 }
3247 }
3248 }
3249 return null;
3250 }
3251
3252 private static Method searchMethods(Method[] methods,
3253 String name,
3254 Class<?>[] parameterTypes)
3255 {
3256 Method res = null;
3257 String internedName = name.intern();
3258 for (Method m : methods) {
3259 if (m.getName() == internedName
3260 && arrayContentsEq(parameterTypes, m.getParameterTypes())
3261 && (res == null
3262 || res.getReturnType().isAssignableFrom(m.getReturnType())))
3263 res = m;
3264 }
3265
3266 return (res == null ? res : getReflectionFactory().copyMethod(res));
3267 }
3268
3269 private Method getMethod0(String name, Class<?>[] parameterTypes, boolean includeStaticMethods) {
3270 MethodArray interfaceCandidates = new MethodArray(2);
3271 Method res = privateGetMethodRecursive(name, parameterTypes, includeStaticMethods, interfaceCandidates);
3272 if (res != null)
3273 return res;
3274
3275 // Not found on class or superclass directly
3276 interfaceCandidates.removeLessSpecifics();
3277 return interfaceCandidates.getFirst(); // may be null
3278 }
3279
3280 private Method privateGetMethodRecursive(String name,
3281 Class<?>[] parameterTypes,
3282 boolean includeStaticMethods,
3283 MethodArray allInterfaceCandidates) {
3284 // Note: the intent is that the search algorithm this routine
3285 // uses be equivalent to the ordering imposed by
3286 // privateGetPublicMethods(). It fetches only the declared
3287 // public methods for each class, however, to reduce the
3288 // number of Method objects which have to be created for the
3289 // common case where the method being requested is declared in
3290 // the class which is being queried.
3291 //
3292 // Due to default methods, unless a method is found on a superclass,
3293 // methods declared in any superinterface needs to be considered.
3294 // Collect all candidates declared in superinterfaces in {@code
3295 // allInterfaceCandidates} and select the most specific if no match on
3296 // a superclass is found.
3297
3298 // Must _not_ return root methods
3299 Method res;
3300 // Search declared public methods
3301 if ((res = searchMethods(privateGetDeclaredMethods(true),
3302 name,
3303 parameterTypes)) != null) {
3304 if (includeStaticMethods || !Modifier.isStatic(res.getModifiers()))
3305 return res;
3306 }
3307 // Search superclass's methods
3308 if (!isInterface()) {
3309 Class<? super T> c = getSuperclass();
3310 if (c != null) {
3311 if ((res = c.getMethod0(name, parameterTypes, true)) != null) {
3312 return res;
3313 }
3314 }
3315 }
3316 // Search superinterfaces' methods
3317 Class<?>[] interfaces = getInterfaces();
3318 for (Class<?> c : interfaces)
3319 if ((res = c.getMethod0(name, parameterTypes, false)) != null)
3320 allInterfaceCandidates.add(res);
3321 // Not found
3322 return null;
3323 }
3324
3325 private Constructor<T> getConstructor0(Class<?>[] parameterTypes,
3326 int which) throws NoSuchMethodException
3327 {
3328 Constructor<T>[] constructors = privateGetDeclaredConstructors((which == Member.PUBLIC));
3329 for (Constructor<T> constructor : constructors) {
3330 if (arrayContentsEq(parameterTypes,
3331 constructor.getParameterTypes())) {
3332 return getReflectionFactory().copyConstructor(constructor);
3333 }
3334 }
3335 throw new NoSuchMethodException(getName() + ".<init>" + argumentTypesToString(parameterTypes));
3336 }
3337
3338 //
3339 // Other helpers and base implementation
3340 //
3341
3342 private static boolean arrayContentsEq(Object[] a1, Object[] a2) {
3343 if (a1 == null) {
3344 return a2 == null || a2.length == 0;
3345 }
3346
3347 if (a2 == null) {
3348 return a1.length == 0;
3349 }
3350
3351 if (a1.length != a2.length) {
3352 return false;
3353 }
3354
3355 for (int i = 0; i < a1.length; i++) {
3356 if (a1[i] != a2[i]) {
3357 return false;
3358 }
3359 }
3360
3361 return true;
3362 }
3363
3364 private static Field[] copyFields(Field[] arg) {
3365 Field[] out = new Field[arg.length];
3366 ReflectionFactory fact = getReflectionFactory();
3367 for (int i = 0; i < arg.length; i++) {
3368 out[i] = fact.copyField(arg[i]);
3369 }
3370 return out;
3371 }
3372
3373 private static Method[] copyMethods(Method[] arg) {
3374 Method[] out = new Method[arg.length];
3375 ReflectionFactory fact = getReflectionFactory();
3376 for (int i = 0; i < arg.length; i++) {
3377 out[i] = fact.copyMethod(arg[i]);
3378 }
3379 return out;
3380 }
3381
3382 private static <U> Constructor<U>[] copyConstructors(Constructor<U>[] arg) {
3383 Constructor<U>[] out = arg.clone();
3384 ReflectionFactory fact = getReflectionFactory();
3385 for (int i = 0; i < out.length; i++) {
3386 out[i] = fact.copyConstructor(out[i]);
3387 }
3388 return out;
3389 }
3390
3391 private native Field[] getDeclaredFields0(boolean publicOnly);
3392 private native Method[] getDeclaredMethods0(boolean publicOnly);
3393 private native Constructor<T>[] getDeclaredConstructors0(boolean publicOnly);
3394 private native Class<?>[] getDeclaredClasses0();
3395
3396 private static String argumentTypesToString(Class<?>[] argTypes) {
3397 StringJoiner sj = new StringJoiner(", ", "(", ")");
3398 if (argTypes != null) {
3399 for (int i = 0; i < argTypes.length; i++) {
3400 Class<?> c = argTypes[i];
3401 sj.add((c == null) ? "null" : c.getName());
3402 }
3403 }
3404 return sj.toString();
3405 }
3406
3407 /** use serialVersionUID from JDK 1.1 for interoperability */
3408 private static final long serialVersionUID = 3206093459760846163L;
3409
3410
3411 /**
3412 * Class Class is special cased within the Serialization Stream Protocol.
3413 *
3414 * A Class instance is written initially into an ObjectOutputStream in the
3415 * following format:
3416 * <pre>
3417 * {@code TC_CLASS} ClassDescriptor
3418 * A ClassDescriptor is a special cased serialization of
3419 * a {@code java.io.ObjectStreamClass} instance.
3420 * </pre>
3421 * A new handle is generated for the initial time the class descriptor
3422 * is written into the stream. Future references to the class descriptor
3423 * are written as references to the initial class descriptor instance.
3424 *
3425 * @see java.io.ObjectStreamClass
3426 */
3427 private static final ObjectStreamField[] serialPersistentFields =
3428 new ObjectStreamField[0];
3429
3430
3431 /**
3432 * Returns the assertion status that would be assigned to this
3433 * class if it were to be initialized at the time this method is invoked.
3434 * If this class has had its assertion status set, the most recent
3435 * setting will be returned; otherwise, if any package default assertion
3436 * status pertains to this class, the most recent setting for the most
3437 * specific pertinent package default assertion status is returned;
3438 * otherwise, if this class is not a system class (i.e., it has a
3439 * class loader) its class loader's default assertion status is returned;
3440 * otherwise, the system class default assertion status is returned.
3441 * <p>
3442 * Few programmers will have any need for this method; it is provided
3443 * for the benefit of the JRE itself. (It allows a class to determine at
3444 * the time that it is initialized whether assertions should be enabled.)
3445 * Note that this method is not guaranteed to return the actual
3446 * assertion status that was (or will be) associated with the specified
3447 * class when it was (or will be) initialized.
3448 *
3449 * @return the desired assertion status of the specified class.
3450 * @see java.lang.ClassLoader#setClassAssertionStatus
3451 * @see java.lang.ClassLoader#setPackageAssertionStatus
3452 * @see java.lang.ClassLoader#setDefaultAssertionStatus
3453 * @since 1.4
3454 */
3455 public boolean desiredAssertionStatus() {
3456 ClassLoader loader = getClassLoader();
3457 // If the loader is null this is a system class, so ask the VM
3458 if (loader == null)
3459 return desiredAssertionStatus0(this);
3460
3461 // If the classloader has been initialized with the assertion
3462 // directives, ask it. Otherwise, ask the VM.
3463 synchronized(loader.assertionLock) {
3464 if (loader.classAssertionStatus != null) {
3465 return loader.desiredAssertionStatus(getName());
3466 }
3467 }
3468 return desiredAssertionStatus0(this);
3469 }
3470
3471 // Retrieves the desired assertion status of this class from the VM
3472 private static native boolean desiredAssertionStatus0(Class<?> clazz);
3473
3474 /**
3475 * Returns true if and only if this class was declared as an enum in the
3476 * source code.
3477 *
3478 * @return true if and only if this class was declared as an enum in the
3479 * source code
3480 * @since 1.5
3481 */
3482 public boolean isEnum() {
3483 // An enum must both directly extend java.lang.Enum and have
3484 // the ENUM bit set; classes for specialized enum constants
3485 // don't do the former.
3486 return (this.getModifiers() & ENUM) != 0 &&
3487 this.getSuperclass() == java.lang.Enum.class;
3488 }
3489
3490 // Fetches the factory for reflective objects
3491 private static ReflectionFactory getReflectionFactory() {
3492 if (reflectionFactory == null) {
3493 reflectionFactory =
3494 java.security.AccessController.doPrivileged
3495 (new ReflectionFactory.GetReflectionFactoryAction());
3496 }
3497 return reflectionFactory;
3498 }
3499 private static ReflectionFactory reflectionFactory;
3500
3501 // To be able to query system properties as soon as they're available
3502 private static boolean initted = false;
3503 private static void checkInitted() {
3504 if (initted) return;
3505 AccessController.doPrivileged(new PrivilegedAction<>() {
3506 public Void run() {
3507 // Tests to ensure the system properties table is fully
3508 // initialized. This is needed because reflection code is
3509 // called very early in the initialization process (before
3510 // command-line arguments have been parsed and therefore
3511 // these user-settable properties installed.) We assume that
3512 // if System.out is non-null then the System class has been
3513 // fully initialized and that the bulk of the startup code
3514 // has been run.
3515
3516 if (System.out == null) {
3517 // java.lang.System not yet fully initialized
3518 return null;
3519 }
3520
3521 // Doesn't use Boolean.getBoolean to avoid class init.
3522 String val =
3523 System.getProperty("sun.reflect.noCaches");
3524 if (val != null && val.equals("true")) {
3525 useCaches = false;
3526 }
3527
3528 initted = true;
3529 return null;
3530 }
3531 });
3532 }
3533
3534 /**
3535 * Returns the elements of this enum class or null if this
3536 * Class object does not represent an enum type.
3537 *
3538 * @return an array containing the values comprising the enum class
3539 * represented by this Class object in the order they're
3540 * declared, or null if this Class object does not
3541 * represent an enum type
3542 * @since 1.5
3543 */
3544 public T[] getEnumConstants() {
3545 T[] values = getEnumConstantsShared();
3546 return (values != null) ? values.clone() : null;
3547 }
3548
3549 /**
3550 * Returns the elements of this enum class or null if this
3551 * Class object does not represent an enum type;
3552 * identical to getEnumConstants except that the result is
3553 * uncloned, cached, and shared by all callers.
3554 */
3555 T[] getEnumConstantsShared() {
3556 T[] constants = enumConstants;
3557 if (constants == null) {
3558 if (!isEnum()) return null;
3559 try {
3560 final Method values = getMethod("values");
3561 java.security.AccessController.doPrivileged(
3562 new java.security.PrivilegedAction<>() {
3563 public Void run() {
3564 values.setAccessible(true);
3565 return null;
3566 }
3567 });
3568 @SuppressWarnings("unchecked")
3569 T[] temporaryConstants = (T[])values.invoke(null);
3570 enumConstants = constants = temporaryConstants;
3571 }
3572 // These can happen when users concoct enum-like classes
3573 // that don't comply with the enum spec.
3574 catch (InvocationTargetException | NoSuchMethodException |
3575 IllegalAccessException ex) { return null; }
3576 }
3577 return constants;
3578 }
3579 private transient volatile T[] enumConstants;
3580
3581 /**
3582 * Returns a map from simple name to enum constant. This package-private
3583 * method is used internally by Enum to implement
3584 * {@code public static <T extends Enum<T>> T valueOf(Class<T>, String)}
3585 * efficiently. Note that the map is returned by this method is
3586 * created lazily on first use. Typically it won't ever get created.
3587 */
3588 Map<String, T> enumConstantDirectory() {
3589 Map<String, T> directory = enumConstantDirectory;
3590 if (directory == null) {
3591 T[] universe = getEnumConstantsShared();
3592 if (universe == null)
3593 throw new IllegalArgumentException(
3594 getName() + " is not an enum type");
3595 directory = new HashMap<>(2 * universe.length);
3596 for (T constant : universe) {
3597 directory.put(((Enum<?>)constant).name(), constant);
3598 }
3599 enumConstantDirectory = directory;
3600 }
3601 return directory;
3602 }
3603 private transient volatile Map<String, T> enumConstantDirectory;
3604
3605 /**
3606 * Casts an object to the class or interface represented
3607 * by this {@code Class} object.
3608 *
3609 * @param obj the object to be cast
3610 * @return the object after casting, or null if obj is null
3611 *
3612 * @throws ClassCastException if the object is not
3613 * null and is not assignable to the type T.
3614 *
3615 * @since 1.5
3616 */
3617 @SuppressWarnings("unchecked")
3618 @HotSpotIntrinsicCandidate
3619 public T cast(Object obj) {
3620 if (obj != null && !isInstance(obj))
3621 throw new ClassCastException(cannotCastMsg(obj));
3622 return (T) obj;
3623 }
3624
3625 private String cannotCastMsg(Object obj) {
3626 return "Cannot cast " + obj.getClass().getName() + " to " + getName();
3627 }
3628
3629 /**
3630 * Casts this {@code Class} object to represent a subclass of the class
3631 * represented by the specified class object. Checks that the cast
3632 * is valid, and throws a {@code ClassCastException} if it is not. If
3633 * this method succeeds, it always returns a reference to this class object.
3634 *
3635 * <p>This method is useful when a client needs to "narrow" the type of
3636 * a {@code Class} object to pass it to an API that restricts the
3637 * {@code Class} objects that it is willing to accept. A cast would
3638 * generate a compile-time warning, as the correctness of the cast
3639 * could not be checked at runtime (because generic types are implemented
3640 * by erasure).
3641 *
3642 * @param <U> the type to cast this class object to
3643 * @param clazz the class of the type to cast this class object to
3644 * @return this {@code Class} object, cast to represent a subclass of
3645 * the specified class object.
3646 * @throws ClassCastException if this {@code Class} object does not
3647 * represent a subclass of the specified class (here "subclass" includes
3648 * the class itself).
3649 * @since 1.5
3650 */
3651 @SuppressWarnings("unchecked")
3652 public <U> Class<? extends U> asSubclass(Class<U> clazz) {
3653 if (clazz.isAssignableFrom(this))
3654 return (Class<? extends U>) this;
3655 else
3656 throw new ClassCastException(this.toString());
3657 }
3658
3659 /**
3660 * @throws NullPointerException {@inheritDoc}
3661 * @since 1.5
3662 */
3663 @SuppressWarnings("unchecked")
3664 public <A extends Annotation> A getAnnotation(Class<A> annotationClass) {
3665 Objects.requireNonNull(annotationClass);
3666
3667 return (A) annotationData().annotations.get(annotationClass);
3668 }
3669
3670 /**
3671 * {@inheritDoc}
3672 * @throws NullPointerException {@inheritDoc}
3673 * @since 1.5
3674 */
3675 @Override
3676 public boolean isAnnotationPresent(Class<? extends Annotation> annotationClass) {
3677 return GenericDeclaration.super.isAnnotationPresent(annotationClass);
3678 }
3679
3680 /**
3681 * @throws NullPointerException {@inheritDoc}
3682 * @since 1.8
3683 */
3684 @Override
3685 public <A extends Annotation> A[] getAnnotationsByType(Class<A> annotationClass) {
3686 Objects.requireNonNull(annotationClass);
3687
3688 AnnotationData annotationData = annotationData();
3689 return AnnotationSupport.getAssociatedAnnotations(annotationData.declaredAnnotations,
3690 this,
3691 annotationClass);
3692 }
3693
3694 /**
3695 * @since 1.5
3696 */
3697 public Annotation[] getAnnotations() {
3698 return AnnotationParser.toArray(annotationData().annotations);
3699 }
3700
3701 /**
3702 * @throws NullPointerException {@inheritDoc}
3703 * @since 1.8
3704 */
3705 @Override
3706 @SuppressWarnings("unchecked")
3707 public <A extends Annotation> A getDeclaredAnnotation(Class<A> annotationClass) {
3708 Objects.requireNonNull(annotationClass);
3709
3710 return (A) annotationData().declaredAnnotations.get(annotationClass);
3711 }
3712
3713 /**
3714 * @throws NullPointerException {@inheritDoc}
3715 * @since 1.8
3716 */
3717 @Override
3718 public <A extends Annotation> A[] getDeclaredAnnotationsByType(Class<A> annotationClass) {
3719 Objects.requireNonNull(annotationClass);
3720
3721 return AnnotationSupport.getDirectlyAndIndirectlyPresent(annotationData().declaredAnnotations,
3722 annotationClass);
3723 }
3724
3725 /**
3726 * @since 1.5
3727 */
3728 public Annotation[] getDeclaredAnnotations() {
3729 return AnnotationParser.toArray(annotationData().declaredAnnotations);
3730 }
3731
3732 // annotation data that might get invalidated when JVM TI RedefineClasses() is called
3733 private static class AnnotationData {
3734 final Map<Class<? extends Annotation>, Annotation> annotations;
3735 final Map<Class<? extends Annotation>, Annotation> declaredAnnotations;
3736
3737 // Value of classRedefinedCount when we created this AnnotationData instance
3738 final int redefinedCount;
3739
3740 AnnotationData(Map<Class<? extends Annotation>, Annotation> annotations,
3741 Map<Class<? extends Annotation>, Annotation> declaredAnnotations,
3742 int redefinedCount) {
3743 this.annotations = annotations;
3744 this.declaredAnnotations = declaredAnnotations;
3745 this.redefinedCount = redefinedCount;
3746 }
3747 }
3748
3749 // Annotations cache
3750 @SuppressWarnings("UnusedDeclaration")
3751 private transient volatile AnnotationData annotationData;
3752
3753 private AnnotationData annotationData() {
3754 while (true) { // retry loop
3755 AnnotationData annotationData = this.annotationData;
3756 int classRedefinedCount = this.classRedefinedCount;
3757 if (annotationData != null &&
3758 annotationData.redefinedCount == classRedefinedCount) {
3759 return annotationData;
3760 }
3761 // null or stale annotationData -> optimistically create new instance
3762 AnnotationData newAnnotationData = createAnnotationData(classRedefinedCount);
3763 // try to install it
3764 if (Atomic.casAnnotationData(this, annotationData, newAnnotationData)) {
3765 // successfully installed new AnnotationData
3766 return newAnnotationData;
3767 }
3768 }
3769 }
3770
3771 private AnnotationData createAnnotationData(int classRedefinedCount) {
3772 Map<Class<? extends Annotation>, Annotation> declaredAnnotations =
3773 AnnotationParser.parseAnnotations(getRawAnnotations(), getConstantPool(), this);
3774 Class<?> superClass = getSuperclass();
3775 Map<Class<? extends Annotation>, Annotation> annotations = null;
3776 if (superClass != null) {
3777 Map<Class<? extends Annotation>, Annotation> superAnnotations =
3778 superClass.annotationData().annotations;
3779 for (Map.Entry<Class<? extends Annotation>, Annotation> e : superAnnotations.entrySet()) {
3780 Class<? extends Annotation> annotationClass = e.getKey();
3781 if (AnnotationType.getInstance(annotationClass).isInherited()) {
3782 if (annotations == null) { // lazy construction
3783 annotations = new LinkedHashMap<>((Math.max(
3784 declaredAnnotations.size(),
3785 Math.min(12, declaredAnnotations.size() + superAnnotations.size())
3786 ) * 4 + 2) / 3
3787 );
3788 }
3789 annotations.put(annotationClass, e.getValue());
3790 }
3791 }
3792 }
3793 if (annotations == null) {
3794 // no inherited annotations -> share the Map with declaredAnnotations
3795 annotations = declaredAnnotations;
3796 } else {
3797 // at least one inherited annotation -> declared may override inherited
3798 annotations.putAll(declaredAnnotations);
3799 }
3800 return new AnnotationData(annotations, declaredAnnotations, classRedefinedCount);
3801 }
3802
3803 // Annotation types cache their internal (AnnotationType) form
3804
3805 @SuppressWarnings("UnusedDeclaration")
3806 private transient volatile AnnotationType annotationType;
3807
3808 boolean casAnnotationType(AnnotationType oldType, AnnotationType newType) {
3809 return Atomic.casAnnotationType(this, oldType, newType);
3810 }
3811
3812 AnnotationType getAnnotationType() {
3813 return annotationType;
3814 }
3815
3816 Map<Class<? extends Annotation>, Annotation> getDeclaredAnnotationMap() {
3817 return annotationData().declaredAnnotations;
3818 }
3819
3820 /* Backing store of user-defined values pertaining to this class.
3821 * Maintained by the ClassValue class.
3822 */
3823 transient ClassValue.ClassValueMap classValueMap;
3824
3825 /**
3826 * Returns an {@code AnnotatedType} object that represents the use of a
3827 * type to specify the superclass of the entity represented by this {@code
3828 * Class} object. (The <em>use</em> of type Foo to specify the superclass
3829 * in '... extends Foo' is distinct from the <em>declaration</em> of type
3830 * Foo.)
3831 *
3832 * <p> If this {@code Class} object represents a type whose declaration
3833 * does not explicitly indicate an annotated superclass, then the return
3834 * value is an {@code AnnotatedType} object representing an element with no
3835 * annotations.
3836 *
3837 * <p> If this {@code Class} represents either the {@code Object} class, an
3838 * interface type, an array type, a primitive type, or void, the return
3839 * value is {@code null}.
3840 *
3841 * @return an object representing the superclass
3842 * @since 1.8
3843 */
3844 public AnnotatedType getAnnotatedSuperclass() {
3845 if (this == Object.class ||
3846 isInterface() ||
3847 isArray() ||
3848 isPrimitive() ||
3849 this == Void.TYPE) {
3850 return null;
3851 }
3852
3853 return TypeAnnotationParser.buildAnnotatedSuperclass(getRawTypeAnnotations(), getConstantPool(), this);
3854 }
3855
3856 /**
3857 * Returns an array of {@code AnnotatedType} objects that represent the use
3858 * of types to specify superinterfaces of the entity represented by this
3859 * {@code Class} object. (The <em>use</em> of type Foo to specify a
3860 * superinterface in '... implements Foo' is distinct from the
3861 * <em>declaration</em> of type Foo.)
3862 *
3863 * <p> If this {@code Class} object represents a class, the return value is
3864 * an array containing objects representing the uses of interface types to
3865 * specify interfaces implemented by the class. The order of the objects in
3866 * the array corresponds to the order of the interface types used in the
3867 * 'implements' clause of the declaration of this {@code Class} object.
3868 *
3869 * <p> If this {@code Class} object represents an interface, the return
3870 * value is an array containing objects representing the uses of interface
3871 * types to specify interfaces directly extended by the interface. The
3872 * order of the objects in the array corresponds to the order of the
3873 * interface types used in the 'extends' clause of the declaration of this
3874 * {@code Class} object.
3875 *
3876 * <p> If this {@code Class} object represents a class or interface whose
3877 * declaration does not explicitly indicate any annotated superinterfaces,
3878 * the return value is an array of length 0.
3879 *
3880 * <p> If this {@code Class} object represents either the {@code Object}
3881 * class, an array type, a primitive type, or void, the return value is an
3882 * array of length 0.
3883 *
3884 * @return an array representing the superinterfaces
3885 * @since 1.8
3886 */
3887 public AnnotatedType[] getAnnotatedInterfaces() {
3888 return TypeAnnotationParser.buildAnnotatedInterfaces(getRawTypeAnnotations(), getConstantPool(), this);
3889 }
3890 }