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