1 /*
2 * Copyright (c) 1994, 2010, 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.Array;
29 import java.lang.reflect.GenericArrayType;
30 import java.lang.reflect.Member;
31 import java.lang.reflect.Field;
32 import java.lang.reflect.Method;
33 import java.lang.reflect.Constructor;
34 import java.lang.reflect.GenericDeclaration;
35 import java.lang.reflect.Modifier;
36 import java.lang.reflect.Type;
37 import java.lang.reflect.TypeVariable;
38 import java.lang.reflect.InvocationTargetException;
39 import java.lang.ref.SoftReference;
40 import java.io.InputStream;
41 import java.io.ObjectStreamField;
42 import java.security.AccessController;
43 import java.security.PrivilegedAction;
44 import java.util.ArrayList;
45 import java.util.Arrays;
46 import java.util.Collection;
47 import java.util.HashSet;
48 import java.util.Iterator;
49 import java.util.List;
50 import java.util.LinkedList;
51 import java.util.LinkedHashSet;
52 import java.util.Set;
53 import java.util.Map;
54 import java.util.HashMap;
55 import sun.misc.Unsafe;
56 import sun.reflect.ConstantPool;
57 import sun.reflect.Reflection;
58 import sun.reflect.ReflectionFactory;
59 import sun.reflect.SignatureIterator;
60 import sun.reflect.generics.factory.CoreReflectionFactory;
61 import sun.reflect.generics.factory.GenericsFactory;
62 import sun.reflect.generics.repository.ClassRepository;
63 import sun.reflect.generics.repository.MethodRepository;
64 import sun.reflect.generics.repository.ConstructorRepository;
65 import sun.reflect.generics.scope.ClassScope;
66 import sun.security.util.SecurityConstants;
67 import java.lang.annotation.Annotation;
68 import sun.reflect.annotation;
69
70 /**
71 * Instances of the class {@code Class} represent classes and
72 * interfaces in a running Java application. An enum is a kind of
73 * class and an annotation is a kind of interface. Every array also
74 * belongs to a class that is reflected as a {@code Class} object
75 * that is shared by all arrays with the same element type and number
76 * of dimensions. The primitive Java types ({@code boolean},
77 * {@code byte}, {@code char}, {@code short},
78 * {@code int}, {@code long}, {@code float}, and
79 * {@code double}), and the keyword {@code void} are also
80 * represented as {@code Class} objects.
81 *
82 * <p> {@code Class} has no public constructor. Instead {@code Class}
83 * objects are constructed automatically by the Java Virtual Machine as classes
84 * are loaded and by calls to the {@code defineClass} method in the class
85 * loader.
86 *
87 * <p> The following example uses a {@code Class} object to print the
88 * class name of an object:
89 *
90 * <p> <blockquote><pre>
91 * void printClassName(Object obj) {
92 * System.out.println("The class of " + obj +
93 * " is " + obj.getClass().getName());
94 * }
95 * </pre></blockquote>
96 *
97 * <p> It is also possible to get the {@code Class} object for a named
98 * type (or for void) using a class literal. See Section 15.8.2 of
99 * <cite>The Java™ Language Specification</cite>.
100 * For example:
101 *
102 * <p> <blockquote>
103 * {@code System.out.println("The name of class Foo is: "+Foo.class.getName());}
104 * </blockquote>
105 *
106 * @param <T> the type of the class modeled by this {@code Class}
107 * object. For example, the type of {@code String.class} is {@code
108 * Class<String>}. Use {@code Class<?>} if the class being modeled is
109 * unknown.
110 *
111 * @author unascribed
112 * @see java.lang.ClassLoader#defineClass(byte[], int, int)
113 * @since JDK1.0
114 */
115 public final
116 class Class<T> implements java.io.Serializable,
117 java.lang.reflect.GenericDeclaration,
118 java.lang.reflect.Type,
119 java.lang.reflect.AnnotatedElement {
120 private static final int ANNOTATION= 0x00002000;
121 private static final int ENUM = 0x00004000;
122 private static final int SYNTHETIC = 0x00001000;
123
124 private static native void registerNatives();
125 static {
126 registerNatives();
127 }
128
129 /*
130 * Constructor. Only the Java Virtual Machine creates Class
131 * objects.
132 */
133 private Class() {}
134
135
136 /**
137 * Converts the object to a string. The string representation is the
138 * string "class" or "interface", followed by a space, and then by the
139 * fully qualified name of the class in the format returned by
140 * {@code getName}. If this {@code Class} object represents a
141 * primitive type, this method returns the name of the primitive type. If
142 * this {@code Class} object represents void this method returns
143 * "void".
144 *
145 * @return a string representation of this class object.
146 */
147 public String toString() {
148 return (isInterface() ? "interface " : (isPrimitive() ? "" : "class "))
149 + getName();
150 }
151
152
153 /**
154 * Returns the {@code Class} object associated with the class or
155 * interface with the given string name. Invoking this method is
156 * equivalent to:
157 *
158 * <blockquote>
159 * {@code Class.forName(className, true, currentLoader)}
160 * </blockquote>
161 *
162 * where {@code currentLoader} denotes the defining class loader of
163 * the current class.
164 *
165 * <p> For example, the following code fragment returns the
166 * runtime {@code Class} descriptor for the class named
167 * {@code java.lang.Thread}:
168 *
169 * <blockquote>
170 * {@code Class t = Class.forName("java.lang.Thread")}
171 * </blockquote>
172 * <p>
173 * A call to {@code forName("X")} causes the class named
174 * {@code X} to be initialized.
175 *
176 * @param className the fully qualified name of the desired class.
177 * @return the {@code Class} object for the class with the
178 * specified name.
179 * @exception LinkageError if the linkage fails
180 * @exception ExceptionInInitializerError if the initialization provoked
181 * by this method fails
182 * @exception ClassNotFoundException if the class cannot be located
183 */
184 public static Class<?> forName(String className)
185 throws ClassNotFoundException {
186 return forName0(className, true, ClassLoader.getCallerClassLoader());
187 }
188
189
190 /**
191 * Returns the {@code Class} object associated with the class or
192 * interface with the given string name, using the given class loader.
193 * Given the fully qualified name for a class or interface (in the same
194 * format returned by {@code getName}) this method attempts to
195 * locate, load, and link the class or interface. The specified class
196 * loader is used to load the class or interface. If the parameter
197 * {@code loader} is null, the class is loaded through the bootstrap
198 * class loader. The class is initialized only if the
199 * {@code initialize} parameter is {@code true} and if it has
200 * not been initialized earlier.
201 *
202 * <p> If {@code name} denotes a primitive type or void, an attempt
203 * will be made to locate a user-defined class in the unnamed package whose
204 * name is {@code name}. Therefore, this method cannot be used to
205 * obtain any of the {@code Class} objects representing primitive
206 * types or void.
207 *
208 * <p> If {@code name} denotes an array class, the component type of
209 * the array class is loaded but not initialized.
210 *
211 * <p> For example, in an instance method the expression:
212 *
213 * <blockquote>
214 * {@code Class.forName("Foo")}
215 * </blockquote>
216 *
217 * is equivalent to:
218 *
219 * <blockquote>
220 * {@code Class.forName("Foo", true, this.getClass().getClassLoader())}
221 * </blockquote>
222 *
223 * Note that this method throws errors related to loading, linking or
224 * initializing as specified in Sections 12.2, 12.3 and 12.4 of <em>The
225 * Java Language Specification</em>.
226 * Note that this method does not check whether the requested class
227 * is accessible to its caller.
228 *
229 * <p> If the {@code loader} is {@code null}, and a security
230 * manager is present, and the caller's class loader is not null, then this
231 * method calls the security manager's {@code checkPermission} method
232 * with a {@code RuntimePermission("getClassLoader")} permission to
233 * ensure it's ok to access the bootstrap class loader.
234 *
235 * @param name fully qualified name of the desired class
236 * @param initialize whether the class must be initialized
237 * @param loader class loader from which the class must be loaded
238 * @return class object representing the desired class
239 *
240 * @exception LinkageError if the linkage fails
241 * @exception ExceptionInInitializerError if the initialization provoked
242 * by this method fails
243 * @exception ClassNotFoundException if the class cannot be located by
244 * the specified class loader
245 *
246 * @see java.lang.Class#forName(String)
247 * @see java.lang.ClassLoader
248 * @since 1.2
249 */
250 public static Class<?> forName(String name, boolean initialize,
251 ClassLoader loader)
252 throws ClassNotFoundException
253 {
254 if (loader == null) {
255 SecurityManager sm = System.getSecurityManager();
256 if (sm != null) {
257 ClassLoader ccl = ClassLoader.getCallerClassLoader();
258 if (ccl != null) {
259 sm.checkPermission(
260 SecurityConstants.GET_CLASSLOADER_PERMISSION);
261 }
262 }
263 }
264 return forName0(name, initialize, loader);
265 }
266
267 /** Called after security checks have been made. */
268 private static native Class<?> forName0(String name, boolean initialize,
269 ClassLoader loader)
270 throws ClassNotFoundException;
271
272 /**
273 * Creates a new instance of the class represented by this {@code Class}
274 * object. The class is instantiated as if by a {@code new}
275 * expression with an empty argument list. The class is initialized if it
276 * has not already been initialized.
277 *
278 * <p>Note that this method propagates any exception thrown by the
279 * nullary constructor, including a checked exception. Use of
280 * this method effectively bypasses the compile-time exception
281 * checking that would otherwise be performed by the compiler.
282 * The {@link
283 * java.lang.reflect.Constructor#newInstance(java.lang.Object...)
284 * Constructor.newInstance} method avoids this problem by wrapping
285 * any exception thrown by the constructor in a (checked) {@link
286 * java.lang.reflect.InvocationTargetException}.
287 *
288 * @return a newly allocated instance of the class represented by this
289 * object.
290 * @exception IllegalAccessException if the class or its nullary
291 * constructor is not accessible.
292 * @exception InstantiationException
293 * if this {@code Class} represents an abstract class,
294 * an interface, an array class, a primitive type, or void;
295 * or if the class has no nullary constructor;
296 * or if the instantiation fails for some other reason.
297 * @exception ExceptionInInitializerError if the initialization
298 * provoked by this method fails.
299 * @exception SecurityException
300 * If a security manager, <i>s</i>, is present and any of the
301 * following conditions is met:
302 *
303 * <ul>
304 *
305 * <li> invocation of
306 * {@link SecurityManager#checkMemberAccess
307 * s.checkMemberAccess(this, Member.PUBLIC)} denies
308 * creation of new instances of this class
309 *
310 * <li> the caller's class loader is not the same as or an
311 * ancestor of the class loader for the current class and
312 * invocation of {@link SecurityManager#checkPackageAccess
313 * s.checkPackageAccess()} denies access to the package
314 * of this class
315 *
316 * </ul>
317 *
318 */
319 public T newInstance()
320 throws InstantiationException, IllegalAccessException
321 {
322 if (System.getSecurityManager() != null) {
323 checkMemberAccess(Member.PUBLIC, ClassLoader.getCallerClassLoader());
324 }
325 return newInstance0();
326 }
327
328 private T newInstance0()
329 throws InstantiationException, IllegalAccessException
330 {
331 // NOTE: the following code may not be strictly correct under
332 // the current Java memory model.
333
334 // Constructor lookup
335 if (cachedConstructor == null) {
336 if (this == Class.class) {
337 throw new IllegalAccessException(
338 "Can not call newInstance() on the Class for java.lang.Class"
339 );
340 }
341 try {
342 Class<?>[] empty = {};
343 final Constructor<T> c = getConstructor0(empty, Member.DECLARED);
344 // Disable accessibility checks on the constructor
345 // since we have to do the security check here anyway
346 // (the stack depth is wrong for the Constructor's
347 // security check to work)
348 java.security.AccessController.doPrivileged(
349 new java.security.PrivilegedAction<Void>() {
350 public Void run() {
351 c.setAccessible(true);
352 return null;
353 }
354 });
355 cachedConstructor = c;
356 } catch (NoSuchMethodException e) {
357 throw new InstantiationException(getName());
358 }
359 }
360 Constructor<T> tmpConstructor = cachedConstructor;
361 // Security check (same as in java.lang.reflect.Constructor)
362 int modifiers = tmpConstructor.getModifiers();
363 if (!Reflection.quickCheckMemberAccess(this, modifiers)) {
364 Class<?> caller = Reflection.getCallerClass(3);
365 if (newInstanceCallerCache != caller) {
366 Reflection.ensureMemberAccess(caller, this, null, modifiers);
367 newInstanceCallerCache = caller;
368 }
369 }
370 // Run constructor
371 try {
372 return tmpConstructor.newInstance((Object[])null);
373 } catch (InvocationTargetException e) {
374 Unsafe.getUnsafe().throwException(e.getTargetException());
375 // Not reached
376 return null;
377 }
378 }
379 private volatile transient Constructor<T> cachedConstructor;
380 private volatile transient Class<?> newInstanceCallerCache;
381
382
383 /**
384 * Determines if the specified {@code Object} is assignment-compatible
385 * with the object represented by this {@code Class}. This method is
386 * the dynamic equivalent of the Java language {@code instanceof}
387 * operator. The method returns {@code true} if the specified
388 * {@code Object} argument is non-null and can be cast to the
389 * reference type represented by this {@code Class} object without
390 * raising a {@code ClassCastException.} It returns {@code false}
391 * otherwise.
392 *
393 * <p> Specifically, if this {@code Class} object represents a
394 * declared class, this method returns {@code true} if the specified
395 * {@code Object} argument is an instance of the represented class (or
396 * of any of its subclasses); it returns {@code false} otherwise. If
397 * this {@code Class} object represents an array class, this method
398 * returns {@code true} if the specified {@code Object} argument
399 * can be converted to an object of the array class by an identity
400 * conversion or by a widening reference conversion; it returns
401 * {@code false} otherwise. If this {@code Class} object
402 * represents an interface, this method returns {@code true} if the
403 * class or any superclass of the specified {@code Object} argument
404 * implements this interface; it returns {@code false} otherwise. If
405 * this {@code Class} object represents a primitive type, this method
406 * returns {@code false}.
407 *
408 * @param obj the object to check
409 * @return true if {@code obj} is an instance of this class
410 *
411 * @since JDK1.1
412 */
413 public native boolean isInstance(Object obj);
414
415
416 /**
417 * Determines if the class or interface represented by this
418 * {@code Class} object is either the same as, or is a superclass or
419 * superinterface of, the class or interface represented by the specified
420 * {@code Class} parameter. It returns {@code true} if so;
421 * otherwise it returns {@code false}. If this {@code Class}
422 * object represents a primitive type, this method returns
423 * {@code true} if the specified {@code Class} parameter is
424 * exactly this {@code Class} object; otherwise it returns
425 * {@code false}.
426 *
427 * <p> Specifically, this method tests whether the type represented by the
428 * specified {@code Class} parameter can be converted to the type
429 * represented by this {@code Class} object via an identity conversion
430 * or via a widening reference conversion. See <em>The Java Language
431 * Specification</em>, sections 5.1.1 and 5.1.4 , for details.
432 *
433 * @param cls the {@code Class} object to be checked
434 * @return the {@code boolean} value indicating whether objects of the
435 * type {@code cls} can be assigned to objects of this class
436 * @exception NullPointerException if the specified Class parameter is
437 * null.
438 * @since JDK1.1
439 */
440 public native boolean isAssignableFrom(Class<?> cls);
441
442
443 /**
444 * Determines if the specified {@code Class} object represents an
445 * interface type.
446 *
447 * @return {@code true} if this object represents an interface;
448 * {@code false} otherwise.
449 */
450 public native boolean isInterface();
451
452
453 /**
454 * Determines if this {@code Class} object represents an array class.
455 *
456 * @return {@code true} if this object represents an array class;
457 * {@code false} otherwise.
458 * @since JDK1.1
459 */
460 public native boolean isArray();
461
462
463 /**
464 * Determines if the specified {@code Class} object represents a
465 * primitive type.
466 *
467 * <p> There are nine predefined {@code Class} objects to represent
468 * the eight primitive types and void. These are created by the Java
469 * Virtual Machine, and have the same names as the primitive types that
470 * they represent, namely {@code boolean}, {@code byte},
471 * {@code char}, {@code short}, {@code int},
472 * {@code long}, {@code float}, and {@code double}.
473 *
474 * <p> These objects may only be accessed via the following public static
475 * final variables, and are the only {@code Class} objects for which
476 * this method returns {@code true}.
477 *
478 * @return true if and only if this class represents a primitive type
479 *
480 * @see java.lang.Boolean#TYPE
481 * @see java.lang.Character#TYPE
482 * @see java.lang.Byte#TYPE
483 * @see java.lang.Short#TYPE
484 * @see java.lang.Integer#TYPE
485 * @see java.lang.Long#TYPE
486 * @see java.lang.Float#TYPE
487 * @see java.lang.Double#TYPE
488 * @see java.lang.Void#TYPE
489 * @since JDK1.1
490 */
491 public native boolean isPrimitive();
492
493 /**
494 * Returns true if this {@code Class} object represents an annotation
495 * type. Note that if this method returns true, {@link #isInterface()}
496 * would also return true, as all annotation types are also interfaces.
497 *
498 * @return {@code true} if this class object represents an annotation
499 * type; {@code false} otherwise
500 * @since 1.5
501 */
502 public boolean isAnnotation() {
503 return (getModifiers() & ANNOTATION) != 0;
504 }
505
506 /**
507 * Returns {@code true} if this class is a synthetic class;
508 * returns {@code false} otherwise.
509 * @return {@code true} if and only if this class is a synthetic class as
510 * defined by the Java Language Specification.
511 * @since 1.5
512 */
513 public boolean isSynthetic() {
514 return (getModifiers() & SYNTHETIC) != 0;
515 }
516
517 /**
518 * Returns the name of the entity (class, interface, array class,
519 * primitive type, or void) represented by this {@code Class} object,
520 * as a {@code String}.
521 *
522 * <p> If this class object represents a reference type that is not an
523 * array type then the binary name of the class is returned, as specified
524 * by
525 * <cite>The Java™ Language Specification</cite>.
526 *
527 * <p> If this class object represents a primitive type or void, then the
528 * name returned is a {@code String} equal to the Java language
529 * keyword corresponding to the primitive type or void.
530 *
531 * <p> If this class object represents a class of arrays, then the internal
532 * form of the name consists of the name of the element type preceded by
533 * one or more '{@code [}' characters representing the depth of the array
534 * nesting. The encoding of element type names is as follows:
535 *
536 * <blockquote><table summary="Element types and encodings">
537 * <tr><th> Element Type <th> <th> Encoding
538 * <tr><td> boolean <td> <td align=center> Z
539 * <tr><td> byte <td> <td align=center> B
540 * <tr><td> char <td> <td align=center> C
541 * <tr><td> class or interface
542 * <td> <td align=center> L<i>classname</i>;
543 * <tr><td> double <td> <td align=center> D
544 * <tr><td> float <td> <td align=center> F
545 * <tr><td> int <td> <td align=center> I
546 * <tr><td> long <td> <td align=center> J
547 * <tr><td> short <td> <td align=center> S
548 * </table></blockquote>
549 *
550 * <p> The class or interface name <i>classname</i> is the binary name of
551 * the class specified above.
552 *
553 * <p> Examples:
554 * <blockquote><pre>
555 * String.class.getName()
556 * returns "java.lang.String"
557 * byte.class.getName()
558 * returns "byte"
559 * (new Object[3]).getClass().getName()
560 * returns "[Ljava.lang.Object;"
561 * (new int[3][4][5][6][7][8][9]).getClass().getName()
562 * returns "[[[[[[[I"
563 * </pre></blockquote>
564 *
565 * @return the name of the class or interface
566 * represented by this object.
567 */
568 public String getName() {
569 String name = this.name;
570 if (name == null)
571 this.name = name = getName0();
572 return name;
573 }
574
575 // cache the name to reduce the number of calls into the VM
576 private transient String name;
577 private native String getName0();
578
579 /**
580 * Returns the class loader for the class. Some implementations may use
581 * null to represent the bootstrap class loader. This method will return
582 * null in such implementations if this class was loaded by the bootstrap
583 * class loader.
584 *
585 * <p> If a security manager is present, and the caller's class loader is
586 * not null and the caller's class loader is not the same as or an ancestor of
587 * the class loader for the class whose class loader is requested, then
588 * this method calls the security manager's {@code checkPermission}
589 * method with a {@code RuntimePermission("getClassLoader")}
590 * permission to ensure it's ok to access the class loader for the class.
591 *
592 * <p>If this object
593 * represents a primitive type or void, null is returned.
594 *
595 * @return the class loader that loaded the class or interface
596 * represented by this object.
597 * @throws SecurityException
598 * if a security manager exists and its
599 * {@code checkPermission} method denies
600 * access to the class loader for the class.
601 * @see java.lang.ClassLoader
602 * @see SecurityManager#checkPermission
603 * @see java.lang.RuntimePermission
604 */
605 public ClassLoader getClassLoader() {
606 ClassLoader cl = getClassLoader0();
607 if (cl == null)
608 return null;
609 SecurityManager sm = System.getSecurityManager();
610 if (sm != null) {
611 ClassLoader ccl = ClassLoader.getCallerClassLoader();
612 if (ccl != null && ccl != cl && !cl.isAncestor(ccl)) {
613 sm.checkPermission(SecurityConstants.GET_CLASSLOADER_PERMISSION);
614 }
615 }
616 return cl;
617 }
618
619 // Package-private to allow ClassLoader access
620 native ClassLoader getClassLoader0();
621
622
623 /**
624 * Returns an array of {@code TypeVariable} objects that represent the
625 * type variables declared by the generic declaration represented by this
626 * {@code GenericDeclaration} object, in declaration order. Returns an
627 * array of length 0 if the underlying generic declaration declares no type
628 * variables.
629 *
630 * @return an array of {@code TypeVariable} objects that represent
631 * the type variables declared by this generic declaration
632 * @throws java.lang.reflect.GenericSignatureFormatError if the generic
633 * signature of this generic declaration does not conform to
634 * the format specified in
635 * <cite>The Java™ Virtual Machine Specification</cite>
636 * @since 1.5
637 */
638 public TypeVariable<Class<T>>[] getTypeParameters() {
639 if (getGenericSignature() != null)
640 return (TypeVariable<Class<T>>[])getGenericInfo().getTypeParameters();
641 else
642 return (TypeVariable<Class<T>>[])new TypeVariable<?>[0];
643 }
644
645
646 /**
647 * Returns the {@code Class} representing the superclass of the entity
648 * (class, interface, primitive type or void) represented by this
649 * {@code Class}. If this {@code Class} represents either the
650 * {@code Object} class, an interface, a primitive type, or void, then
651 * null is returned. If this object represents an array class then the
652 * {@code Class} object representing the {@code Object} class is
653 * returned.
654 *
655 * @return the superclass of the class represented by this object.
656 */
657 public native Class<? super T> getSuperclass();
658
659
660 /**
661 * Returns the {@code Type} representing the direct superclass of
662 * the entity (class, interface, primitive type or void) represented by
663 * this {@code Class}.
664 *
665 * <p>If the superclass is a parameterized type, the {@code Type}
666 * object returned must accurately reflect the actual type
667 * parameters used in the source code. The parameterized type
668 * representing the superclass is created if it had not been
669 * created before. See the declaration of {@link
670 * java.lang.reflect.ParameterizedType ParameterizedType} for the
671 * semantics of the creation process for parameterized types. If
672 * this {@code Class} represents either the {@code Object}
673 * class, an interface, a primitive type, or void, then null is
674 * returned. If this object represents an array class then the
675 * {@code Class} object representing the {@code Object} class is
676 * returned.
677 *
678 * @throws java.lang.reflect.GenericSignatureFormatError if the generic
679 * class signature does not conform to the format specified in
680 * <cite>The Java™ Virtual Machine Specification</cite>
681 * @throws TypeNotPresentException if the generic superclass
682 * refers to a non-existent type declaration
683 * @throws java.lang.reflect.MalformedParameterizedTypeException if the
684 * generic superclass refers to a parameterized type that cannot be
685 * instantiated for any reason
686 * @return the superclass of the class represented by this object
687 * @since 1.5
688 */
689 public Type getGenericSuperclass() {
690 if (getGenericSignature() != null) {
691 // Historical irregularity:
692 // Generic signature marks interfaces with superclass = Object
693 // but this API returns null for interfaces
694 if (isInterface())
695 return null;
696 return getGenericInfo().getSuperclass();
697 } else
698 return getSuperclass();
699 }
700
701 /**
702 * Gets the package for this class. The class loader of this class is used
703 * to find the package. If the class was loaded by the bootstrap class
704 * loader the set of packages loaded from CLASSPATH is searched to find the
705 * package of the class. Null is returned if no package object was created
706 * by the class loader of this class.
707 *
708 * <p> Packages have attributes for versions and specifications only if the
709 * information was defined in the manifests that accompany the classes, and
710 * if the class loader created the package instance with the attributes
711 * from the manifest.
712 *
713 * @return the package of the class, or null if no package
714 * information is available from the archive or codebase.
715 */
716 public Package getPackage() {
717 return Package.getPackage(this);
718 }
719
720
721 /**
722 * Determines the interfaces implemented by the class or interface
723 * represented by this object.
724 *
725 * <p> If this object represents a class, the return value is an array
726 * containing objects representing all interfaces implemented by the
727 * class. The order of the interface objects in the array corresponds to
728 * the order of the interface names in the {@code implements} clause
729 * of the declaration of the class represented by this object. For
730 * example, given the declaration:
731 * <blockquote>
732 * {@code class Shimmer implements FloorWax, DessertTopping { ... }}
733 * </blockquote>
734 * suppose the value of {@code s} is an instance of
735 * {@code Shimmer}; the value of the expression:
736 * <blockquote>
737 * {@code s.getClass().getInterfaces()[0]}
738 * </blockquote>
739 * is the {@code Class} object that represents interface
740 * {@code FloorWax}; and the value of:
741 * <blockquote>
742 * {@code s.getClass().getInterfaces()[1]}
743 * </blockquote>
744 * is the {@code Class} object that represents interface
745 * {@code DessertTopping}.
746 *
747 * <p> If this object represents an interface, the array contains objects
748 * representing all interfaces extended by the interface. The order of the
749 * interface objects in the array corresponds to the order of the interface
750 * names in the {@code extends} clause of the declaration of the
751 * interface represented by this object.
752 *
753 * <p> If this object represents a class or interface that implements no
754 * interfaces, the method returns an array of length 0.
755 *
756 * <p> If this object represents a primitive type or void, the method
757 * returns an array of length 0.
758 *
759 * @return an array of interfaces implemented by this class.
760 */
761 public native Class<?>[] getInterfaces();
762
763 /**
764 * Returns the {@code Type}s representing the interfaces
765 * directly implemented by the class or interface represented by
766 * this object.
767 *
768 * <p>If a superinterface is a parameterized type, the
769 * {@code Type} object returned for it must accurately reflect
770 * the actual type parameters used in the source code. The
771 * parameterized type representing each superinterface is created
772 * if it had not been created before. See the declaration of
773 * {@link java.lang.reflect.ParameterizedType ParameterizedType}
774 * for the semantics of the creation process for parameterized
775 * types.
776 *
777 * <p> If this object represents a class, the return value is an
778 * array containing objects representing all interfaces
779 * implemented by the class. The order of the interface objects in
780 * the array corresponds to the order of the interface names in
781 * the {@code implements} clause of the declaration of the class
782 * represented by this object. In the case of an array class, the
783 * interfaces {@code Cloneable} and {@code Serializable} are
784 * returned in that order.
785 *
786 * <p>If this object represents an interface, the array contains
787 * objects representing all interfaces directly extended by the
788 * interface. The order of the interface objects in the array
789 * corresponds to the order of the interface names in the
790 * {@code extends} clause of the declaration of the interface
791 * represented by this object.
792 *
793 * <p>If this object represents a class or interface that
794 * implements no interfaces, the method returns an array of length
795 * 0.
796 *
797 * <p>If this object represents a primitive type or void, the
798 * method returns an array of length 0.
799 *
800 * @throws java.lang.reflect.GenericSignatureFormatError
801 * if the generic class signature does not conform to the format
802 * specified in
803 * <cite>The Java™ Virtual Machine Specification</cite>
804 * @throws TypeNotPresentException if any of the generic
805 * superinterfaces refers to a non-existent type declaration
806 * @throws java.lang.reflect.MalformedParameterizedTypeException
807 * if any of the generic superinterfaces refer to a parameterized
808 * type that cannot be instantiated for any reason
809 * @return an array of interfaces implemented by this class
810 * @since 1.5
811 */
812 public Type[] getGenericInterfaces() {
813 if (getGenericSignature() != null)
814 return getGenericInfo().getSuperInterfaces();
815 else
816 return getInterfaces();
817 }
818
819
820 /**
821 * Returns the {@code Class} representing the component type of an
822 * array. If this class does not represent an array class this method
823 * returns null.
824 *
825 * @return the {@code Class} representing the component type of this
826 * class if this class is an array
827 * @see java.lang.reflect.Array
828 * @since JDK1.1
829 */
830 public native Class<?> getComponentType();
831
832
833 /**
834 * Returns the Java language modifiers for this class or interface, encoded
835 * in an integer. The modifiers consist of the Java Virtual Machine's
836 * constants for {@code public}, {@code protected},
837 * {@code private}, {@code final}, {@code static},
838 * {@code abstract} and {@code interface}; they should be decoded
839 * using the methods of class {@code Modifier}.
840 *
841 * <p> If the underlying class is an array class, then its
842 * {@code public}, {@code private} and {@code protected}
843 * modifiers are the same as those of its component type. If this
844 * {@code Class} represents a primitive type or void, its
845 * {@code public} modifier is always {@code true}, and its
846 * {@code protected} and {@code private} modifiers are always
847 * {@code false}. If this object represents an array class, a
848 * primitive type or void, then its {@code final} modifier is always
849 * {@code true} and its interface modifier is always
850 * {@code false}. The values of its other modifiers are not determined
851 * by this specification.
852 *
853 * <p> The modifier encodings are defined in <em>The Java Virtual Machine
854 * Specification</em>, table 4.1.
855 *
856 * @return the {@code int} representing the modifiers for this class
857 * @see java.lang.reflect.Modifier
858 * @since JDK1.1
859 */
860 public native int getModifiers();
861
862
863 /**
864 * Gets the signers of this class.
865 *
866 * @return the signers of this class, or null if there are no signers. In
867 * particular, this method returns null if this object represents
868 * a primitive type or void.
869 * @since JDK1.1
870 */
871 public native Object[] getSigners();
872
873
874 /**
875 * Set the signers of this class.
876 */
877 native void setSigners(Object[] signers);
878
879
880 /**
881 * If this {@code Class} object represents a local or anonymous
882 * class within a method, returns a {@link
883 * java.lang.reflect.Method Method} object representing the
884 * immediately enclosing method of the underlying class. Returns
885 * {@code null} otherwise.
886 *
887 * In particular, this method returns {@code null} if the underlying
888 * class is a local or anonymous class immediately enclosed by a type
889 * declaration, instance initializer or static initializer.
890 *
891 * @return the immediately enclosing method of the underlying class, if
892 * that class is a local or anonymous class; otherwise {@code null}.
893 * @since 1.5
894 */
895 public Method getEnclosingMethod() {
896 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
897
898 if (enclosingInfo == null)
899 return null;
900 else {
901 if (!enclosingInfo.isMethod())
902 return null;
903
904 MethodRepository typeInfo = MethodRepository.make(enclosingInfo.getDescriptor(),
905 getFactory());
906 Class<?> returnType = toClass(typeInfo.getReturnType());
907 Type [] parameterTypes = typeInfo.getParameterTypes();
908 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length];
909
910 // Convert Types to Classes; returned types *should*
911 // be class objects since the methodDescriptor's used
912 // don't have generics information
913 for(int i = 0; i < parameterClasses.length; i++)
914 parameterClasses[i] = toClass(parameterTypes[i]);
915
916 /*
917 * Loop over all declared methods; match method name,
918 * number of and type of parameters, *and* return
919 * type. Matching return type is also necessary
920 * because of covariant returns, etc.
921 */
922 for(Method m: enclosingInfo.getEnclosingClass().getDeclaredMethods()) {
923 if (m.getName().equals(enclosingInfo.getName()) ) {
924 Class<?>[] candidateParamClasses = m.getParameterTypes();
925 if (candidateParamClasses.length == parameterClasses.length) {
926 boolean matches = true;
927 for(int i = 0; i < candidateParamClasses.length; i++) {
928 if (!candidateParamClasses[i].equals(parameterClasses[i])) {
929 matches = false;
930 break;
931 }
932 }
933
934 if (matches) { // finally, check return type
935 if (m.getReturnType().equals(returnType) )
936 return m;
937 }
938 }
939 }
940 }
941
942 throw new InternalError("Enclosing method not found");
943 }
944 }
945
946 private native Object[] getEnclosingMethod0();
947
948 private EnclosingMethodInfo getEnclosingMethodInfo() {
949 Object[] enclosingInfo = getEnclosingMethod0();
950 if (enclosingInfo == null)
951 return null;
952 else {
953 return new EnclosingMethodInfo(enclosingInfo);
954 }
955 }
956
957 private final static class EnclosingMethodInfo {
958 private Class<?> enclosingClass;
959 private String name;
960 private String descriptor;
961
962 private EnclosingMethodInfo(Object[] enclosingInfo) {
963 if (enclosingInfo.length != 3)
964 throw new InternalError("Malformed enclosing method information");
965 try {
966 // The array is expected to have three elements:
967
968 // the immediately enclosing class
969 enclosingClass = (Class<?>) enclosingInfo[0];
970 assert(enclosingClass != null);
971
972 // the immediately enclosing method or constructor's
973 // name (can be null).
974 name = (String) enclosingInfo[1];
975
976 // the immediately enclosing method or constructor's
977 // descriptor (null iff name is).
978 descriptor = (String) enclosingInfo[2];
979 assert((name != null && descriptor != null) || name == descriptor);
980 } catch (ClassCastException cce) {
981 throw new InternalError("Invalid type in enclosing method information");
982 }
983 }
984
985 boolean isPartial() {
986 return enclosingClass == null || name == null || descriptor == null;
987 }
988
989 boolean isConstructor() { return !isPartial() && "<init>".equals(name); }
990
991 boolean isMethod() { return !isPartial() && !isConstructor() && !"<clinit>".equals(name); }
992
993 Class<?> getEnclosingClass() { return enclosingClass; }
994
995 String getName() { return name; }
996
997 String getDescriptor() { return descriptor; }
998
999 }
1000
1001 private static Class<?> toClass(Type o) {
1002 if (o instanceof GenericArrayType)
1003 return Array.newInstance(toClass(((GenericArrayType)o).getGenericComponentType()),
1004 0)
1005 .getClass();
1006 return (Class<?>)o;
1007 }
1008
1009 /**
1010 * If this {@code Class} object represents a local or anonymous
1011 * class within a constructor, returns a {@link
1012 * java.lang.reflect.Constructor Constructor} object representing
1013 * the immediately enclosing constructor of the underlying
1014 * class. Returns {@code null} otherwise. In particular, this
1015 * method returns {@code null} if the underlying class is a local
1016 * or anonymous class immediately enclosed by a type declaration,
1017 * instance initializer or static initializer.
1018 *
1019 * @return the immediately enclosing constructor of the underlying class, if
1020 * that class is a local or anonymous class; otherwise {@code null}.
1021 * @since 1.5
1022 */
1023 public Constructor<?> getEnclosingConstructor() {
1024 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1025
1026 if (enclosingInfo == null)
1027 return null;
1028 else {
1029 if (!enclosingInfo.isConstructor())
1030 return null;
1031
1032 ConstructorRepository typeInfo = ConstructorRepository.make(enclosingInfo.getDescriptor(),
1033 getFactory());
1034 Type [] parameterTypes = typeInfo.getParameterTypes();
1035 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length];
1036
1037 // Convert Types to Classes; returned types *should*
1038 // be class objects since the methodDescriptor's used
1039 // don't have generics information
1040 for(int i = 0; i < parameterClasses.length; i++)
1041 parameterClasses[i] = toClass(parameterTypes[i]);
1042
1043 /*
1044 * Loop over all declared constructors; match number
1045 * of and type of parameters.
1046 */
1047 for(Constructor<?> c: enclosingInfo.getEnclosingClass().getDeclaredConstructors()) {
1048 Class<?>[] candidateParamClasses = c.getParameterTypes();
1049 if (candidateParamClasses.length == parameterClasses.length) {
1050 boolean matches = true;
1051 for(int i = 0; i < candidateParamClasses.length; i++) {
1052 if (!candidateParamClasses[i].equals(parameterClasses[i])) {
1053 matches = false;
1054 break;
1055 }
1056 }
1057
1058 if (matches)
1059 return c;
1060 }
1061 }
1062
1063 throw new InternalError("Enclosing constructor not found");
1064 }
1065 }
1066
1067
1068 /**
1069 * If the class or interface represented by this {@code Class} object
1070 * is a member of another class, returns the {@code Class} object
1071 * representing the class in which it was declared. This method returns
1072 * null if this class or interface is not a member of any other class. If
1073 * this {@code Class} object represents an array class, a primitive
1074 * type, or void,then this method returns null.
1075 *
1076 * @return the declaring class for this class
1077 * @since JDK1.1
1078 */
1079 public native Class<?> getDeclaringClass();
1080
1081
1082 /**
1083 * Returns the immediately enclosing class of the underlying
1084 * class. If the underlying class is a top level class this
1085 * method returns {@code null}.
1086 * @return the immediately enclosing class of the underlying class
1087 * @since 1.5
1088 */
1089 public Class<?> getEnclosingClass() {
1090 // There are five kinds of classes (or interfaces):
1091 // a) Top level classes
1092 // b) Nested classes (static member classes)
1093 // c) Inner classes (non-static member classes)
1094 // d) Local classes (named classes declared within a method)
1095 // e) Anonymous classes
1096
1097
1098 // JVM Spec 4.8.6: A class must have an EnclosingMethod
1099 // attribute if and only if it is a local class or an
1100 // anonymous class.
1101 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1102
1103 if (enclosingInfo == null) {
1104 // This is a top level or a nested class or an inner class (a, b, or c)
1105 return getDeclaringClass();
1106 } else {
1107 Class<?> enclosingClass = enclosingInfo.getEnclosingClass();
1108 // This is a local class or an anonymous class (d or e)
1109 if (enclosingClass == this || enclosingClass == null)
1110 throw new InternalError("Malformed enclosing method information");
1111 else
1112 return enclosingClass;
1113 }
1114 }
1115
1116 /**
1117 * Returns the simple name of the underlying class as given in the
1118 * source code. Returns an empty string if the underlying class is
1119 * anonymous.
1120 *
1121 * <p>The simple name of an array is the simple name of the
1122 * component type with "[]" appended. In particular the simple
1123 * name of an array whose component type is anonymous is "[]".
1124 *
1125 * @return the simple name of the underlying class
1126 * @since 1.5
1127 */
1128 public String getSimpleName() {
1129 if (isArray())
1130 return getComponentType().getSimpleName()+"[]";
1131
1132 String simpleName = getSimpleBinaryName();
1133 if (simpleName == null) { // top level class
1134 simpleName = getName();
1135 return simpleName.substring(simpleName.lastIndexOf(".")+1); // strip the package name
1136 }
1137 // According to JLS3 "Binary Compatibility" (13.1) the binary
1138 // name of non-package classes (not top level) is the binary
1139 // name of the immediately enclosing class followed by a '$' followed by:
1140 // (for nested and inner classes): the simple name.
1141 // (for local classes): 1 or more digits followed by the simple name.
1142 // (for anonymous classes): 1 or more digits.
1143
1144 // Since getSimpleBinaryName() will strip the binary name of
1145 // the immediatly enclosing class, we are now looking at a
1146 // string that matches the regular expression "\$[0-9]*"
1147 // followed by a simple name (considering the simple of an
1148 // anonymous class to be the empty string).
1149
1150 // Remove leading "\$[0-9]*" from the name
1151 int length = simpleName.length();
1152 if (length < 1 || simpleName.charAt(0) != '$')
1153 throw new InternalError("Malformed class name");
1154 int index = 1;
1155 while (index < length && isAsciiDigit(simpleName.charAt(index)))
1156 index++;
1157 // Eventually, this is the empty string iff this is an anonymous class
1158 return simpleName.substring(index);
1159 }
1160
1161 /**
1162 * Character.isDigit answers {@code true} to some non-ascii
1163 * digits. This one does not.
1164 */
1165 private static boolean isAsciiDigit(char c) {
1166 return '0' <= c && c <= '9';
1167 }
1168
1169 /**
1170 * Returns the canonical name of the underlying class as
1171 * defined by the Java Language Specification. Returns null if
1172 * the underlying class does not have a canonical name (i.e., if
1173 * it is a local or anonymous class or an array whose component
1174 * type does not have a canonical name).
1175 * @return the canonical name of the underlying class if it exists, and
1176 * {@code null} otherwise.
1177 * @since 1.5
1178 */
1179 public String getCanonicalName() {
1180 if (isArray()) {
1181 String canonicalName = getComponentType().getCanonicalName();
1182 if (canonicalName != null)
1183 return canonicalName + "[]";
1184 else
1185 return null;
1186 }
1187 if (isLocalOrAnonymousClass())
1188 return null;
1189 Class<?> enclosingClass = getEnclosingClass();
1190 if (enclosingClass == null) { // top level class
1191 return getName();
1192 } else {
1193 String enclosingName = enclosingClass.getCanonicalName();
1194 if (enclosingName == null)
1195 return null;
1196 return enclosingName + "." + getSimpleName();
1197 }
1198 }
1199
1200 /**
1201 * Returns {@code true} if and only if the underlying class
1202 * is an anonymous class.
1203 *
1204 * @return {@code true} if and only if this class is an anonymous class.
1205 * @since 1.5
1206 */
1207 public boolean isAnonymousClass() {
1208 return "".equals(getSimpleName());
1209 }
1210
1211 /**
1212 * Returns {@code true} if and only if the underlying class
1213 * is a local class.
1214 *
1215 * @return {@code true} if and only if this class is a local class.
1216 * @since 1.5
1217 */
1218 public boolean isLocalClass() {
1219 return isLocalOrAnonymousClass() && !isAnonymousClass();
1220 }
1221
1222 /**
1223 * Returns {@code true} if and only if the underlying class
1224 * is a member class.
1225 *
1226 * @return {@code true} if and only if this class is a member class.
1227 * @since 1.5
1228 */
1229 public boolean isMemberClass() {
1230 return getSimpleBinaryName() != null && !isLocalOrAnonymousClass();
1231 }
1232
1233 /**
1234 * Returns the "simple binary name" of the underlying class, i.e.,
1235 * the binary name without the leading enclosing class name.
1236 * Returns {@code null} if the underlying class is a top level
1237 * class.
1238 */
1239 private String getSimpleBinaryName() {
1240 Class<?> enclosingClass = getEnclosingClass();
1241 if (enclosingClass == null) // top level class
1242 return null;
1243 // Otherwise, strip the enclosing class' name
1244 try {
1245 return getName().substring(enclosingClass.getName().length());
1246 } catch (IndexOutOfBoundsException ex) {
1247 throw new InternalError("Malformed class name");
1248 }
1249 }
1250
1251 /**
1252 * Returns {@code true} if this is a local class or an anonymous
1253 * class. Returns {@code false} otherwise.
1254 */
1255 private boolean isLocalOrAnonymousClass() {
1256 // JVM Spec 4.8.6: A class must have an EnclosingMethod
1257 // attribute if and only if it is a local class or an
1258 // anonymous class.
1259 return getEnclosingMethodInfo() != null;
1260 }
1261
1262 /**
1263 * Returns an array containing {@code Class} objects representing all
1264 * the public classes and interfaces that are members of the class
1265 * represented by this {@code Class} object. This includes public
1266 * class and interface members inherited from superclasses and public class
1267 * and interface members declared by the class. This method returns an
1268 * array of length 0 if this {@code Class} object has no public member
1269 * classes or interfaces. This method also returns an array of length 0 if
1270 * this {@code Class} object represents a primitive type, an array
1271 * class, or void.
1272 *
1273 * @return the array of {@code Class} objects representing the public
1274 * members of this class
1275 * @exception SecurityException
1276 * If a security manager, <i>s</i>, is present and any of the
1277 * following conditions is met:
1278 *
1279 * <ul>
1280 *
1281 * <li> invocation of
1282 * {@link SecurityManager#checkMemberAccess
1283 * s.checkMemberAccess(this, Member.PUBLIC)} method
1284 * denies access to the classes within this class
1285 *
1286 * <li> the caller's class loader is not the same as or an
1287 * ancestor of the class loader for the current class and
1288 * invocation of {@link SecurityManager#checkPackageAccess
1289 * s.checkPackageAccess()} denies access to the package
1290 * of this class
1291 *
1292 * </ul>
1293 *
1294 * @since JDK1.1
1295 */
1296 public Class<?>[] getClasses() {
1297 // be very careful not to change the stack depth of this
1298 // checkMemberAccess call for security reasons
1299 // see java.lang.SecurityManager.checkMemberAccess
1300 checkMemberAccess(Member.PUBLIC, ClassLoader.getCallerClassLoader());
1301
1302 // Privileged so this implementation can look at DECLARED classes,
1303 // something the caller might not have privilege to do. The code here
1304 // is allowed to look at DECLARED classes because (1) it does not hand
1305 // out anything other than public members and (2) public member access
1306 // has already been ok'd by the SecurityManager.
1307
1308 return java.security.AccessController.doPrivileged(
1309 new java.security.PrivilegedAction<Class<?>[]>() {
1310 public Class[] run() {
1311 List<Class<?>> list = new ArrayList<>();
1312 Class<?> currentClass = Class.this;
1313 while (currentClass != null) {
1314 Class<?>[] members = currentClass.getDeclaredClasses();
1315 for (int i = 0; i < members.length; i++) {
1316 if (Modifier.isPublic(members[i].getModifiers())) {
1317 list.add(members[i]);
1318 }
1319 }
1320 currentClass = currentClass.getSuperclass();
1321 }
1322 return list.toArray(new Class[0]);
1323 }
1324 });
1325 }
1326
1327
1328 /**
1329 * Returns an array containing {@code Field} objects reflecting all
1330 * the accessible public fields of the class or interface represented by
1331 * this {@code Class} object. The elements in the array returned are
1332 * not sorted and are not in any particular order. This method returns an
1333 * array of length 0 if the class or interface has no accessible public
1334 * fields, or if it represents an array class, a primitive type, or void.
1335 *
1336 * <p> Specifically, if this {@code Class} object represents a class,
1337 * this method returns the public fields of this class and of all its
1338 * superclasses. If this {@code Class} object represents an
1339 * interface, this method returns the fields of this interface and of all
1340 * its superinterfaces.
1341 *
1342 * <p> The implicit length field for array class is not reflected by this
1343 * method. User code should use the methods of class {@code Array} to
1344 * manipulate arrays.
1345 *
1346 * <p> See <em>The Java Language Specification</em>, sections 8.2 and 8.3.
1347 *
1348 * @return the array of {@code Field} objects representing the
1349 * public fields
1350 * @exception SecurityException
1351 * If a security manager, <i>s</i>, is present and any of the
1352 * following conditions is met:
1353 *
1354 * <ul>
1355 *
1356 * <li> invocation of
1357 * {@link SecurityManager#checkMemberAccess
1358 * s.checkMemberAccess(this, Member.PUBLIC)} denies
1359 * access to the fields within this class
1360 *
1361 * <li> the caller's class loader is not the same as or an
1362 * ancestor of the class loader for the current class and
1363 * invocation of {@link SecurityManager#checkPackageAccess
1364 * s.checkPackageAccess()} denies access to the package
1365 * of this class
1366 *
1367 * </ul>
1368 *
1369 * @since JDK1.1
1370 */
1371 public Field[] getFields() throws SecurityException {
1372 // be very careful not to change the stack depth of this
1373 // checkMemberAccess call for security reasons
1374 // see java.lang.SecurityManager.checkMemberAccess
1375 checkMemberAccess(Member.PUBLIC, ClassLoader.getCallerClassLoader());
1376 return copyFields(privateGetPublicFields(null));
1377 }
1378
1379
1380 /**
1381 * Returns an array containing {@code Method} objects reflecting all
1382 * the public <em>member</em> methods of the class or interface represented
1383 * by this {@code Class} object, including those declared by the class
1384 * or interface and those inherited from superclasses and
1385 * superinterfaces. Array classes return all the (public) member methods
1386 * inherited from the {@code Object} class. The elements in the array
1387 * returned are not sorted and are not in any particular order. This
1388 * method returns an array of length 0 if this {@code Class} object
1389 * represents a class or interface that has no public member methods, or if
1390 * this {@code Class} object represents a primitive type or void.
1391 *
1392 * <p> The class initialization method {@code <clinit>} is not
1393 * included in the returned array. If the class declares multiple public
1394 * member methods with the same parameter types, they are all included in
1395 * the returned array.
1396 *
1397 * <p> See <em>The Java Language Specification</em>, sections 8.2 and 8.4.
1398 *
1399 * @return the array of {@code Method} objects representing the
1400 * public methods of this class
1401 * @exception SecurityException
1402 * If a security manager, <i>s</i>, is present and any of the
1403 * following conditions is met:
1404 *
1405 * <ul>
1406 *
1407 * <li> invocation of
1408 * {@link SecurityManager#checkMemberAccess
1409 * s.checkMemberAccess(this, Member.PUBLIC)} denies
1410 * access to the methods within this class
1411 *
1412 * <li> the caller's class loader is not the same as or an
1413 * ancestor of the class loader for the current class and
1414 * invocation of {@link SecurityManager#checkPackageAccess
1415 * s.checkPackageAccess()} denies access to the package
1416 * of this class
1417 *
1418 * </ul>
1419 *
1420 * @since JDK1.1
1421 */
1422 public Method[] getMethods() throws SecurityException {
1423 // be very careful not to change the stack depth of this
1424 // checkMemberAccess call for security reasons
1425 // see java.lang.SecurityManager.checkMemberAccess
1426 checkMemberAccess(Member.PUBLIC, ClassLoader.getCallerClassLoader());
1427 return copyMethods(privateGetPublicMethods());
1428 }
1429
1430
1431 /**
1432 * Returns an array containing {@code Constructor} objects reflecting
1433 * all the public constructors of the class represented by this
1434 * {@code Class} object. An array of length 0 is returned if the
1435 * class has no public constructors, or if the class is an array class, or
1436 * if the class reflects a primitive type or void.
1437 *
1438 * Note that while this method returns an array of {@code
1439 * Constructor<T>} objects (that is an array of constructors from
1440 * this class), the return type of this method is {@code
1441 * Constructor<?>[]} and <em>not</em> {@code Constructor<T>[]} as
1442 * might be expected. This less informative return type is
1443 * necessary since after being returned from this method, the
1444 * array could be modified to hold {@code Constructor} objects for
1445 * different classes, which would violate the type guarantees of
1446 * {@code Constructor<T>[]}.
1447 *
1448 * @return the array of {@code Constructor} objects representing the
1449 * public constructors of this class
1450 * @exception SecurityException
1451 * If a security manager, <i>s</i>, is present and any of the
1452 * following conditions is met:
1453 *
1454 * <ul>
1455 *
1456 * <li> invocation of
1457 * {@link SecurityManager#checkMemberAccess
1458 * s.checkMemberAccess(this, Member.PUBLIC)} denies
1459 * access to the constructors within this class
1460 *
1461 * <li> the caller's class loader is not the same as or an
1462 * ancestor of the class loader for the current class and
1463 * invocation of {@link SecurityManager#checkPackageAccess
1464 * s.checkPackageAccess()} denies access to the package
1465 * of this class
1466 *
1467 * </ul>
1468 *
1469 * @since JDK1.1
1470 */
1471 public Constructor<?>[] getConstructors() throws SecurityException {
1472 // be very careful not to change the stack depth of this
1473 // checkMemberAccess call for security reasons
1474 // see java.lang.SecurityManager.checkMemberAccess
1475 checkMemberAccess(Member.PUBLIC, ClassLoader.getCallerClassLoader());
1476 return copyConstructors(privateGetDeclaredConstructors(true));
1477 }
1478
1479
1480 /**
1481 * Returns a {@code Field} object that reflects the specified public
1482 * member field of the class or interface represented by this
1483 * {@code Class} object. The {@code name} parameter is a
1484 * {@code String} specifying the simple name of the desired field.
1485 *
1486 * <p> The field to be reflected is determined by the algorithm that
1487 * follows. Let C be the class represented by this object:
1488 * <OL>
1489 * <LI> If C declares a public field with the name specified, that is the
1490 * field to be reflected.</LI>
1491 * <LI> If no field was found in step 1 above, this algorithm is applied
1492 * recursively to each direct superinterface of C. The direct
1493 * superinterfaces are searched in the order they were declared.</LI>
1494 * <LI> If no field was found in steps 1 and 2 above, and C has a
1495 * superclass S, then this algorithm is invoked recursively upon S.
1496 * If C has no superclass, then a {@code NoSuchFieldException}
1497 * is thrown.</LI>
1498 * </OL>
1499 *
1500 * <p> See <em>The Java Language Specification</em>, sections 8.2 and 8.3.
1501 *
1502 * @param name the field name
1503 * @return the {@code Field} object of this class specified by
1504 * {@code name}
1505 * @exception NoSuchFieldException if a field with the specified name is
1506 * not found.
1507 * @exception NullPointerException if {@code name} is {@code null}
1508 * @exception SecurityException
1509 * If a security manager, <i>s</i>, is present and any of the
1510 * following conditions is met:
1511 *
1512 * <ul>
1513 *
1514 * <li> invocation of
1515 * {@link SecurityManager#checkMemberAccess
1516 * s.checkMemberAccess(this, Member.PUBLIC)} denies
1517 * access to the field
1518 *
1519 * <li> the caller's class loader is not the same as or an
1520 * ancestor of the class loader for the current class and
1521 * invocation of {@link SecurityManager#checkPackageAccess
1522 * s.checkPackageAccess()} denies access to the package
1523 * of this class
1524 *
1525 * </ul>
1526 *
1527 * @since JDK1.1
1528 */
1529 public Field getField(String name)
1530 throws NoSuchFieldException, SecurityException {
1531 // be very careful not to change the stack depth of this
1532 // checkMemberAccess call for security reasons
1533 // see java.lang.SecurityManager.checkMemberAccess
1534 checkMemberAccess(Member.PUBLIC, ClassLoader.getCallerClassLoader());
1535 Field field = getField0(name);
1536 if (field == null) {
1537 throw new NoSuchFieldException(name);
1538 }
1539 return field;
1540 }
1541
1542
1543 /**
1544 * Returns a {@code Method} object that reflects the specified public
1545 * member method of the class or interface represented by this
1546 * {@code Class} object. The {@code name} parameter is a
1547 * {@code String} specifying the simple name of the desired method. The
1548 * {@code parameterTypes} parameter is an array of {@code Class}
1549 * objects that identify the method's formal parameter types, in declared
1550 * order. If {@code parameterTypes} is {@code null}, it is
1551 * treated as if it were an empty array.
1552 *
1553 * <p> If the {@code name} is "{@code <init>};"or "{@code <clinit>}" a
1554 * {@code NoSuchMethodException} is raised. Otherwise, the method to
1555 * be reflected is determined by the algorithm that follows. Let C be the
1556 * class represented by this object:
1557 * <OL>
1558 * <LI> C is searched for any <I>matching methods</I>. If no matching
1559 * method is found, the algorithm of step 1 is invoked recursively on
1560 * the superclass of C.</LI>
1561 * <LI> If no method was found in step 1 above, the superinterfaces of C
1562 * are searched for a matching method. If any such method is found, it
1563 * is reflected.</LI>
1564 * </OL>
1565 *
1566 * To find a matching method in a class C: If C declares exactly one
1567 * public method with the specified name and exactly the same formal
1568 * parameter types, that is the method reflected. If more than one such
1569 * method is found in C, and one of these methods has a return type that is
1570 * more specific than any of the others, that method is reflected;
1571 * otherwise one of the methods is chosen arbitrarily.
1572 *
1573 * <p>Note that there may be more than one matching method in a
1574 * class because while the Java language forbids a class to
1575 * declare multiple methods with the same signature but different
1576 * return types, the Java virtual machine does not. This
1577 * increased flexibility in the virtual machine can be used to
1578 * implement various language features. For example, covariant
1579 * returns can be implemented with {@linkplain
1580 * java.lang.reflect.Method#isBridge bridge methods}; the bridge
1581 * method and the method being overridden would have the same
1582 * signature but different return types.
1583 *
1584 * <p> See <em>The Java Language Specification</em>, sections 8.2 and 8.4.
1585 *
1586 * @param name the name of the method
1587 * @param parameterTypes the list of parameters
1588 * @return the {@code Method} object that matches the specified
1589 * {@code name} and {@code parameterTypes}
1590 * @exception NoSuchMethodException if a matching method is not found
1591 * or if the name is "<init>"or "<clinit>".
1592 * @exception NullPointerException if {@code name} is {@code null}
1593 * @exception SecurityException
1594 * If a security manager, <i>s</i>, is present and any of the
1595 * following conditions is met:
1596 *
1597 * <ul>
1598 *
1599 * <li> invocation of
1600 * {@link SecurityManager#checkMemberAccess
1601 * s.checkMemberAccess(this, Member.PUBLIC)} denies
1602 * access to the method
1603 *
1604 * <li> the caller's class loader is not the same as or an
1605 * ancestor of the class loader for the current class and
1606 * invocation of {@link SecurityManager#checkPackageAccess
1607 * s.checkPackageAccess()} denies access to the package
1608 * of this class
1609 *
1610 * </ul>
1611 *
1612 * @since JDK1.1
1613 */
1614 public Method getMethod(String name, Class<?>... parameterTypes)
1615 throws NoSuchMethodException, SecurityException {
1616 // be very careful not to change the stack depth of this
1617 // checkMemberAccess call for security reasons
1618 // see java.lang.SecurityManager.checkMemberAccess
1619 checkMemberAccess(Member.PUBLIC, ClassLoader.getCallerClassLoader());
1620 Method method = getMethod0(name, parameterTypes);
1621 if (method == null) {
1622 throw new NoSuchMethodException(getName() + "." + name + argumentTypesToString(parameterTypes));
1623 }
1624 return method;
1625 }
1626
1627
1628 /**
1629 * Returns a {@code Constructor} object that reflects the specified
1630 * public constructor of the class represented by this {@code Class}
1631 * object. The {@code parameterTypes} parameter is an array of
1632 * {@code Class} objects that identify the constructor's formal
1633 * parameter types, in declared order.
1634 *
1635 * If this {@code Class} object represents an inner class
1636 * declared in a non-static context, the formal parameter types
1637 * include the explicit enclosing instance as the first parameter.
1638 *
1639 * <p> The constructor to reflect is the public constructor of the class
1640 * represented by this {@code Class} object whose formal parameter
1641 * types match those specified by {@code parameterTypes}.
1642 *
1643 * @param parameterTypes the parameter array
1644 * @return the {@code Constructor} object of the public constructor that
1645 * matches the specified {@code parameterTypes}
1646 * @exception NoSuchMethodException if a matching method is not found.
1647 * @exception SecurityException
1648 * If a security manager, <i>s</i>, is present and any of the
1649 * following conditions is met:
1650 *
1651 * <ul>
1652 *
1653 * <li> invocation of
1654 * {@link SecurityManager#checkMemberAccess
1655 * s.checkMemberAccess(this, Member.PUBLIC)} denies
1656 * access to the constructor
1657 *
1658 * <li> the caller's class loader is not the same as or an
1659 * ancestor of the class loader for the current class and
1660 * invocation of {@link SecurityManager#checkPackageAccess
1661 * s.checkPackageAccess()} denies access to the package
1662 * of this class
1663 *
1664 * </ul>
1665 *
1666 * @since JDK1.1
1667 */
1668 public Constructor<T> getConstructor(Class<?>... parameterTypes)
1669 throws NoSuchMethodException, SecurityException {
1670 // be very careful not to change the stack depth of this
1671 // checkMemberAccess call for security reasons
1672 // see java.lang.SecurityManager.checkMemberAccess
1673 checkMemberAccess(Member.PUBLIC, ClassLoader.getCallerClassLoader());
1674 return getConstructor0(parameterTypes, Member.PUBLIC);
1675 }
1676
1677
1678 /**
1679 * Returns an array of {@code Class} objects reflecting all the
1680 * classes and interfaces declared as members of the class represented by
1681 * this {@code Class} object. This includes public, protected, default
1682 * (package) access, and private classes and interfaces declared by the
1683 * class, but excludes inherited classes and interfaces. This method
1684 * returns an array of length 0 if the class declares no classes or
1685 * interfaces as members, or if this {@code Class} object represents a
1686 * primitive type, an array class, or void.
1687 *
1688 * @return the array of {@code Class} objects representing all the
1689 * declared members of this class
1690 * @exception SecurityException
1691 * If a security manager, <i>s</i>, is present and any of the
1692 * following conditions is met:
1693 *
1694 * <ul>
1695 *
1696 * <li> invocation of
1697 * {@link SecurityManager#checkMemberAccess
1698 * s.checkMemberAccess(this, Member.DECLARED)} denies
1699 * access to the declared classes within this class
1700 *
1701 * <li> the caller's class loader is not the same as or an
1702 * ancestor of the class loader for the current class and
1703 * invocation of {@link SecurityManager#checkPackageAccess
1704 * s.checkPackageAccess()} denies access to the package
1705 * of this class
1706 *
1707 * </ul>
1708 *
1709 * @since JDK1.1
1710 */
1711 public Class<?>[] getDeclaredClasses() throws SecurityException {
1712 // be very careful not to change the stack depth of this
1713 // checkMemberAccess call for security reasons
1714 // see java.lang.SecurityManager.checkMemberAccess
1715 checkMemberAccess(Member.DECLARED, ClassLoader.getCallerClassLoader());
1716 return getDeclaredClasses0();
1717 }
1718
1719
1720 /**
1721 * Returns an array of {@code Field} objects reflecting all the fields
1722 * declared by the class or interface represented by this
1723 * {@code Class} object. This includes public, protected, default
1724 * (package) access, and private fields, but excludes inherited fields.
1725 * The elements in the array returned are not sorted and are not in any
1726 * particular order. This method returns an array of length 0 if the class
1727 * or interface declares no fields, or if this {@code Class} object
1728 * represents a primitive type, an array class, or void.
1729 *
1730 * <p> See <em>The Java Language Specification</em>, sections 8.2 and 8.3.
1731 *
1732 * @return the array of {@code Field} objects representing all the
1733 * declared fields of this class
1734 * @exception SecurityException
1735 * If a security manager, <i>s</i>, is present and any of the
1736 * following conditions is met:
1737 *
1738 * <ul>
1739 *
1740 * <li> invocation of
1741 * {@link SecurityManager#checkMemberAccess
1742 * s.checkMemberAccess(this, Member.DECLARED)} denies
1743 * access to the declared fields within this class
1744 *
1745 * <li> the caller's class loader is not the same as or an
1746 * ancestor of the class loader for the current class and
1747 * invocation of {@link SecurityManager#checkPackageAccess
1748 * s.checkPackageAccess()} denies access to the package
1749 * of this class
1750 *
1751 * </ul>
1752 *
1753 * @since JDK1.1
1754 */
1755 public Field[] getDeclaredFields() throws SecurityException {
1756 // be very careful not to change the stack depth of this
1757 // checkMemberAccess call for security reasons
1758 // see java.lang.SecurityManager.checkMemberAccess
1759 checkMemberAccess(Member.DECLARED, ClassLoader.getCallerClassLoader());
1760 return copyFields(privateGetDeclaredFields(false));
1761 }
1762
1763
1764 /**
1765 * Returns an array of {@code Method} objects reflecting all the
1766 * methods declared by the class or interface represented by this
1767 * {@code Class} object. This includes public, protected, default
1768 * (package) access, and private methods, but excludes inherited methods.
1769 * The elements in the array returned are not sorted and are not in any
1770 * particular order. This method returns an array of length 0 if the class
1771 * or interface declares no methods, or if this {@code Class} object
1772 * represents a primitive type, an array class, or void. The class
1773 * initialization method {@code <clinit>} is not included in the
1774 * returned array. If the class declares multiple public member methods
1775 * with the same parameter types, they are all included in the returned
1776 * array.
1777 *
1778 * <p> See <em>The Java Language Specification</em>, section 8.2.
1779 *
1780 * @return the array of {@code Method} objects representing all the
1781 * declared methods of this class
1782 * @exception SecurityException
1783 * If a security manager, <i>s</i>, is present and any of the
1784 * following conditions is met:
1785 *
1786 * <ul>
1787 *
1788 * <li> invocation of
1789 * {@link SecurityManager#checkMemberAccess
1790 * s.checkMemberAccess(this, Member.DECLARED)} denies
1791 * access to the declared methods within this class
1792 *
1793 * <li> the caller's class loader is not the same as or an
1794 * ancestor of the class loader for the current class and
1795 * invocation of {@link SecurityManager#checkPackageAccess
1796 * s.checkPackageAccess()} denies access to the package
1797 * of this class
1798 *
1799 * </ul>
1800 *
1801 * @since JDK1.1
1802 */
1803 public Method[] getDeclaredMethods() throws SecurityException {
1804 // be very careful not to change the stack depth of this
1805 // checkMemberAccess call for security reasons
1806 // see java.lang.SecurityManager.checkMemberAccess
1807 checkMemberAccess(Member.DECLARED, ClassLoader.getCallerClassLoader());
1808 return copyMethods(privateGetDeclaredMethods(false));
1809 }
1810
1811
1812 /**
1813 * Returns an array of {@code Constructor} objects reflecting all the
1814 * constructors declared by the class represented by this
1815 * {@code Class} object. These are public, protected, default
1816 * (package) access, and private constructors. The elements in the array
1817 * returned are not sorted and are not in any particular order. If the
1818 * class has a default constructor, it is included in the returned array.
1819 * This method returns an array of length 0 if this {@code Class}
1820 * object represents an interface, a primitive type, an array class, or
1821 * void.
1822 *
1823 * <p> See <em>The Java Language Specification</em>, section 8.2.
1824 *
1825 * @return the array of {@code Constructor} objects representing all the
1826 * declared constructors of this class
1827 * @exception SecurityException
1828 * If a security manager, <i>s</i>, is present and any of the
1829 * following conditions is met:
1830 *
1831 * <ul>
1832 *
1833 * <li> invocation of
1834 * {@link SecurityManager#checkMemberAccess
1835 * s.checkMemberAccess(this, Member.DECLARED)} denies
1836 * access to the declared constructors within this class
1837 *
1838 * <li> 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 * </ul>
1845 *
1846 * @since JDK1.1
1847 */
1848 public Constructor<?>[] getDeclaredConstructors() throws SecurityException {
1849 // be very careful not to change the stack depth of this
1850 // checkMemberAccess call for security reasons
1851 // see java.lang.SecurityManager.checkMemberAccess
1852 checkMemberAccess(Member.DECLARED, ClassLoader.getCallerClassLoader());
1853 return copyConstructors(privateGetDeclaredConstructors(false));
1854 }
1855
1856
1857 /**
1858 * Returns a {@code Field} object that reflects the specified declared
1859 * field of the class or interface represented by this {@code Class}
1860 * object. The {@code name} parameter is a {@code String} that
1861 * specifies the simple name of the desired field. Note that this method
1862 * will not reflect the {@code length} field of an array class.
1863 *
1864 * @param name the name of the field
1865 * @return the {@code Field} object for the specified field in this
1866 * class
1867 * @exception NoSuchFieldException if a field with the specified name is
1868 * not found.
1869 * @exception NullPointerException if {@code name} is {@code null}
1870 * @exception SecurityException
1871 * If a security manager, <i>s</i>, is present and any of the
1872 * following conditions is met:
1873 *
1874 * <ul>
1875 *
1876 * <li> invocation of
1877 * {@link SecurityManager#checkMemberAccess
1878 * s.checkMemberAccess(this, Member.DECLARED)} denies
1879 * access to the declared field
1880 *
1881 * <li> the caller's class loader is not the same as or an
1882 * ancestor of the class loader for the current class and
1883 * invocation of {@link SecurityManager#checkPackageAccess
1884 * s.checkPackageAccess()} denies access to the package
1885 * of this class
1886 *
1887 * </ul>
1888 *
1889 * @since JDK1.1
1890 */
1891 public Field getDeclaredField(String name)
1892 throws NoSuchFieldException, SecurityException {
1893 // be very careful not to change the stack depth of this
1894 // checkMemberAccess call for security reasons
1895 // see java.lang.SecurityManager.checkMemberAccess
1896 checkMemberAccess(Member.DECLARED, ClassLoader.getCallerClassLoader());
1897 Field field = searchFields(privateGetDeclaredFields(false), name);
1898 if (field == null) {
1899 throw new NoSuchFieldException(name);
1900 }
1901 return field;
1902 }
1903
1904
1905 /**
1906 * Returns a {@code Method} object that reflects the specified
1907 * declared method of the class or interface represented by this
1908 * {@code Class} object. The {@code name} parameter is a
1909 * {@code String} that specifies the simple name of the desired
1910 * method, and the {@code parameterTypes} parameter is an array of
1911 * {@code Class} objects that identify the method's formal parameter
1912 * types, in declared order. If more than one method with the same
1913 * parameter types is declared in a class, and one of these methods has a
1914 * return type that is more specific than any of the others, that method is
1915 * returned; otherwise one of the methods is chosen arbitrarily. If the
1916 * name is "<init>"or "<clinit>" a {@code NoSuchMethodException}
1917 * is raised.
1918 *
1919 * @param name the name of the method
1920 * @param parameterTypes the parameter array
1921 * @return the {@code Method} object for the method of this class
1922 * matching the specified name and parameters
1923 * @exception NoSuchMethodException if a matching method is not found.
1924 * @exception NullPointerException if {@code name} is {@code null}
1925 * @exception SecurityException
1926 * If a security manager, <i>s</i>, is present and any of the
1927 * following conditions is met:
1928 *
1929 * <ul>
1930 *
1931 * <li> invocation of
1932 * {@link SecurityManager#checkMemberAccess
1933 * s.checkMemberAccess(this, Member.DECLARED)} denies
1934 * access to the declared method
1935 *
1936 * <li> the caller's class loader is not the same as or an
1937 * ancestor of the class loader for the current class and
1938 * invocation of {@link SecurityManager#checkPackageAccess
1939 * s.checkPackageAccess()} denies access to the package
1940 * of this class
1941 *
1942 * </ul>
1943 *
1944 * @since JDK1.1
1945 */
1946 public Method getDeclaredMethod(String name, Class<?>... parameterTypes)
1947 throws NoSuchMethodException, SecurityException {
1948 // be very careful not to change the stack depth of this
1949 // checkMemberAccess call for security reasons
1950 // see java.lang.SecurityManager.checkMemberAccess
1951 checkMemberAccess(Member.DECLARED, ClassLoader.getCallerClassLoader());
1952 Method method = searchMethods(privateGetDeclaredMethods(false), name, parameterTypes);
1953 if (method == null) {
1954 throw new NoSuchMethodException(getName() + "." + name + argumentTypesToString(parameterTypes));
1955 }
1956 return method;
1957 }
1958
1959
1960 /**
1961 * Returns a {@code Constructor} object that reflects the specified
1962 * constructor of the class or interface represented by this
1963 * {@code Class} object. The {@code parameterTypes} parameter is
1964 * an array of {@code Class} objects that identify the constructor's
1965 * formal parameter types, in declared order.
1966 *
1967 * If this {@code Class} object represents an inner class
1968 * declared in a non-static context, the formal parameter types
1969 * include the explicit enclosing instance as the first parameter.
1970 *
1971 * @param parameterTypes the parameter array
1972 * @return The {@code Constructor} object for the constructor with the
1973 * specified parameter list
1974 * @exception NoSuchMethodException if a matching method is not found.
1975 * @exception SecurityException
1976 * If a security manager, <i>s</i>, is present and any of the
1977 * following conditions is met:
1978 *
1979 * <ul>
1980 *
1981 * <li> invocation of
1982 * {@link SecurityManager#checkMemberAccess
1983 * s.checkMemberAccess(this, Member.DECLARED)} denies
1984 * access to the declared constructor
1985 *
1986 * <li> the caller's class loader is not the same as or an
1987 * ancestor of the class loader for the current class and
1988 * invocation of {@link SecurityManager#checkPackageAccess
1989 * s.checkPackageAccess()} denies access to the package
1990 * of this class
1991 *
1992 * </ul>
1993 *
1994 * @since JDK1.1
1995 */
1996 public Constructor<T> getDeclaredConstructor(Class<?>... parameterTypes)
1997 throws NoSuchMethodException, SecurityException {
1998 // be very careful not to change the stack depth of this
1999 // checkMemberAccess call for security reasons
2000 // see java.lang.SecurityManager.checkMemberAccess
2001 checkMemberAccess(Member.DECLARED, ClassLoader.getCallerClassLoader());
2002 return getConstructor0(parameterTypes, Member.DECLARED);
2003 }
2004
2005 /**
2006 * Finds a resource with a given name. The rules for searching resources
2007 * associated with a given class are implemented by the defining
2008 * {@linkplain ClassLoader class loader} of the class. This method
2009 * delegates to this object's class loader. If this object was loaded by
2010 * the bootstrap class loader, the method delegates to {@link
2011 * ClassLoader#getSystemResourceAsStream}.
2012 *
2013 * <p> Before delegation, an absolute resource name is constructed from the
2014 * given resource name using this algorithm:
2015 *
2016 * <ul>
2017 *
2018 * <li> If the {@code name} begins with a {@code '/'}
2019 * (<tt>'\u002f'</tt>), then the absolute name of the resource is the
2020 * portion of the {@code name} following the {@code '/'}.
2021 *
2022 * <li> Otherwise, the absolute name is of the following form:
2023 *
2024 * <blockquote>
2025 * {@code modified_package_name/name}
2026 * </blockquote>
2027 *
2028 * <p> Where the {@code modified_package_name} is the package name of this
2029 * object with {@code '/'} substituted for {@code '.'}
2030 * (<tt>'\u002e'</tt>).
2031 *
2032 * </ul>
2033 *
2034 * @param name name of the desired resource
2035 * @return A {@link java.io.InputStream} object or {@code null} if
2036 * no resource with this name is found
2037 * @throws NullPointerException If {@code name} is {@code null}
2038 * @since JDK1.1
2039 */
2040 public InputStream getResourceAsStream(String name) {
2041 name = resolveName(name);
2042 ClassLoader cl = getClassLoader0();
2043 if (cl==null) {
2044 // A system class.
2045 return ClassLoader.getSystemResourceAsStream(name);
2046 }
2047 return cl.getResourceAsStream(name);
2048 }
2049
2050 /**
2051 * Finds a resource with a given name. The rules for searching resources
2052 * associated with a given class are implemented by the defining
2053 * {@linkplain ClassLoader class loader} of the class. This method
2054 * delegates to this object's class loader. If this object was loaded by
2055 * the bootstrap class loader, the method delegates to {@link
2056 * ClassLoader#getSystemResource}.
2057 *
2058 * <p> Before delegation, an absolute resource name is constructed from the
2059 * given resource name using this algorithm:
2060 *
2061 * <ul>
2062 *
2063 * <li> If the {@code name} begins with a {@code '/'}
2064 * (<tt>'\u002f'</tt>), then the absolute name of the resource is the
2065 * portion of the {@code name} following the {@code '/'}.
2066 *
2067 * <li> Otherwise, the absolute name is of the following form:
2068 *
2069 * <blockquote>
2070 * {@code modified_package_name/name}
2071 * </blockquote>
2072 *
2073 * <p> Where the {@code modified_package_name} is the package name of this
2074 * object with {@code '/'} substituted for {@code '.'}
2075 * (<tt>'\u002e'</tt>).
2076 *
2077 * </ul>
2078 *
2079 * @param name name of the desired resource
2080 * @return A {@link java.net.URL} object or {@code null} if no
2081 * resource with this name is found
2082 * @since JDK1.1
2083 */
2084 public java.net.URL getResource(String name) {
2085 name = resolveName(name);
2086 ClassLoader cl = getClassLoader0();
2087 if (cl==null) {
2088 // A system class.
2089 return ClassLoader.getSystemResource(name);
2090 }
2091 return cl.getResource(name);
2092 }
2093
2094
2095
2096 /** protection domain returned when the internal domain is null */
2097 private static java.security.ProtectionDomain allPermDomain;
2098
2099
2100 /**
2101 * Returns the {@code ProtectionDomain} of this class. If there is a
2102 * security manager installed, this method first calls the security
2103 * manager's {@code checkPermission} method with a
2104 * {@code RuntimePermission("getProtectionDomain")} permission to
2105 * ensure it's ok to get the
2106 * {@code ProtectionDomain}.
2107 *
2108 * @return the ProtectionDomain of this class
2109 *
2110 * @throws SecurityException
2111 * if a security manager exists and its
2112 * {@code checkPermission} method doesn't allow
2113 * getting the ProtectionDomain.
2114 *
2115 * @see java.security.ProtectionDomain
2116 * @see SecurityManager#checkPermission
2117 * @see java.lang.RuntimePermission
2118 * @since 1.2
2119 */
2120 public java.security.ProtectionDomain getProtectionDomain() {
2121 SecurityManager sm = System.getSecurityManager();
2122 if (sm != null) {
2123 sm.checkPermission(SecurityConstants.GET_PD_PERMISSION);
2124 }
2125 java.security.ProtectionDomain pd = getProtectionDomain0();
2126 if (pd == null) {
2127 if (allPermDomain == null) {
2128 java.security.Permissions perms =
2129 new java.security.Permissions();
2130 perms.add(SecurityConstants.ALL_PERMISSION);
2131 allPermDomain =
2132 new java.security.ProtectionDomain(null, perms);
2133 }
2134 pd = allPermDomain;
2135 }
2136 return pd;
2137 }
2138
2139
2140 /**
2141 * Returns the ProtectionDomain of this class.
2142 */
2143 private native java.security.ProtectionDomain getProtectionDomain0();
2144
2145
2146 /**
2147 * Set the ProtectionDomain for this class. Called by
2148 * ClassLoader.defineClass.
2149 */
2150 native void setProtectionDomain0(java.security.ProtectionDomain pd);
2151
2152
2153 /*
2154 * Return the Virtual Machine's Class object for the named
2155 * primitive type.
2156 */
2157 static native Class getPrimitiveClass(String name);
2158
2159
2160 /*
2161 * Check if client is allowed to access members. If access is denied,
2162 * throw a SecurityException.
2163 *
2164 * Be very careful not to change the stack depth of this checkMemberAccess
2165 * call for security reasons.
2166 * See java.lang.SecurityManager.checkMemberAccess.
2167 *
2168 * <p> Default policy: allow all clients access with normal Java access
2169 * control.
2170 */
2171 private void checkMemberAccess(int which, ClassLoader ccl) {
2172 SecurityManager s = System.getSecurityManager();
2173 if (s != null) {
2174 s.checkMemberAccess(this, which);
2175 ClassLoader cl = getClassLoader0();
2176 if ((ccl != null) && (ccl != cl) &&
2177 ((cl == null) || !cl.isAncestor(ccl))) {
2178 String name = this.getName();
2179 int i = name.lastIndexOf('.');
2180 if (i != -1) {
2181 s.checkPackageAccess(name.substring(0, i));
2182 }
2183 }
2184 }
2185 }
2186
2187 /**
2188 * Add a package name prefix if the name is not absolute Remove leading "/"
2189 * if name is absolute
2190 */
2191 private String resolveName(String name) {
2192 if (name == null) {
2193 return name;
2194 }
2195 if (!name.startsWith("/")) {
2196 Class<?> c = this;
2197 while (c.isArray()) {
2198 c = c.getComponentType();
2199 }
2200 String baseName = c.getName();
2201 int index = baseName.lastIndexOf('.');
2202 if (index != -1) {
2203 name = baseName.substring(0, index).replace('.', '/')
2204 +"/"+name;
2205 }
2206 } else {
2207 name = name.substring(1);
2208 }
2209 return name;
2210 }
2211
2212 /**
2213 * Reflection support.
2214 */
2215
2216 // Caches for certain reflective results
2217 private static boolean useCaches = true;
2218 private volatile transient SoftReference<Field[]> declaredFields;
2219 private volatile transient SoftReference<Field[]> publicFields;
2220 private volatile transient SoftReference<Method[]> declaredMethods;
2221 private volatile transient SoftReference<Method[]> publicMethods;
2222 private volatile transient SoftReference<Constructor<T>[]> declaredConstructors;
2223 private volatile transient SoftReference<Constructor<T>[]> publicConstructors;
2224 // Intermediate results for getFields and getMethods
2225 private volatile transient SoftReference<Field[]> declaredPublicFields;
2226 private volatile transient SoftReference<Method[]> declaredPublicMethods;
2227
2228 // Incremented by the VM on each call to JVM TI RedefineClasses()
2229 // that redefines this class or a superclass.
2230 private volatile transient int classRedefinedCount = 0;
2231
2232 // Value of classRedefinedCount when we last cleared the cached values
2233 // that are sensitive to class redefinition.
2234 private volatile transient int lastRedefinedCount = 0;
2235
2236 // Clears cached values that might possibly have been obsoleted by
2237 // a class redefinition.
2238 private void clearCachesOnClassRedefinition() {
2239 if (lastRedefinedCount != classRedefinedCount) {
2240 declaredFields = publicFields = declaredPublicFields = null;
2241 declaredMethods = publicMethods = declaredPublicMethods = null;
2242 declaredConstructors = publicConstructors = null;
2243 annotations = declaredAnnotations = null;
2244
2245 // Use of "volatile" (and synchronization by caller in the case
2246 // of annotations) ensures that no thread sees the update to
2247 // lastRedefinedCount before seeing the caches cleared.
2248 // We do not guard against brief windows during which multiple
2249 // threads might redundantly work to fill an empty cache.
2250 lastRedefinedCount = classRedefinedCount;
2251 }
2252 }
2253
2254 // Generic signature handling
2255 private native String getGenericSignature();
2256
2257 // Generic info repository; lazily initialized
2258 private transient ClassRepository genericInfo;
2259
2260 // accessor for factory
2261 private GenericsFactory getFactory() {
2262 // create scope and factory
2263 return CoreReflectionFactory.make(this, ClassScope.make(this));
2264 }
2265
2266 // accessor for generic info repository
2267 private ClassRepository getGenericInfo() {
2268 // lazily initialize repository if necessary
2269 if (genericInfo == null) {
2270 // create and cache generic info repository
2271 genericInfo = ClassRepository.make(getGenericSignature(),
2272 getFactory());
2273 }
2274 return genericInfo; //return cached repository
2275 }
2276
2277 // Annotations handling
2278 private native byte[] getRawAnnotations();
2279
2280 native ConstantPool getConstantPool();
2281
2282 //
2283 //
2284 // java.lang.reflect.Field handling
2285 //
2286 //
2287
2288 // Returns an array of "root" fields. These Field objects must NOT
2289 // be propagated to the outside world, but must instead be copied
2290 // via ReflectionFactory.copyField.
2291 private Field[] privateGetDeclaredFields(boolean publicOnly) {
2292 checkInitted();
2293 Field[] res = null;
2294 if (useCaches) {
2295 clearCachesOnClassRedefinition();
2296 if (publicOnly) {
2297 if (declaredPublicFields != null) {
2298 res = declaredPublicFields.get();
2299 }
2300 } else {
2301 if (declaredFields != null) {
2302 res = declaredFields.get();
2303 }
2304 }
2305 if (res != null) return res;
2306 }
2307 // No cached value available; request value from VM
2308 res = Reflection.filterFields(this, getDeclaredFields0(publicOnly));
2309 if (useCaches) {
2310 if (publicOnly) {
2311 declaredPublicFields = new SoftReference<>(res);
2312 } else {
2313 declaredFields = new SoftReference<>(res);
2314 }
2315 }
2316 return res;
2317 }
2318
2319 // Returns an array of "root" fields. These Field objects must NOT
2320 // be propagated to the outside world, but must instead be copied
2321 // via ReflectionFactory.copyField.
2322 private Field[] privateGetPublicFields(Set<Class<?>> traversedInterfaces) {
2323 checkInitted();
2324 Field[] res = null;
2325 if (useCaches) {
2326 clearCachesOnClassRedefinition();
2327 if (publicFields != null) {
2328 res = publicFields.get();
2329 }
2330 if (res != null) return res;
2331 }
2332
2333 // No cached value available; compute value recursively.
2334 // Traverse in correct order for getField().
2335 List<Field> fields = new ArrayList<>();
2336 if (traversedInterfaces == null) {
2337 traversedInterfaces = new HashSet<>();
2338 }
2339
2340 // Local fields
2341 Field[] tmp = privateGetDeclaredFields(true);
2342 addAll(fields, tmp);
2343
2344 // Direct superinterfaces, recursively
2345 for (Class<?> c : getInterfaces()) {
2346 if (!traversedInterfaces.contains(c)) {
2347 traversedInterfaces.add(c);
2348 addAll(fields, c.privateGetPublicFields(traversedInterfaces));
2349 }
2350 }
2351
2352 // Direct superclass, recursively
2353 if (!isInterface()) {
2354 Class<?> c = getSuperclass();
2355 if (c != null) {
2356 addAll(fields, c.privateGetPublicFields(traversedInterfaces));
2357 }
2358 }
2359
2360 res = new Field[fields.size()];
2361 fields.toArray(res);
2362 if (useCaches) {
2363 publicFields = new SoftReference<>(res);
2364 }
2365 return res;
2366 }
2367
2368 private static void addAll(Collection<Field> c, Field[] o) {
2369 for (int i = 0; i < o.length; i++) {
2370 c.add(o[i]);
2371 }
2372 }
2373
2374
2375 //
2376 //
2377 // java.lang.reflect.Constructor handling
2378 //
2379 //
2380
2381 // Returns an array of "root" constructors. These Constructor
2382 // objects must NOT be propagated to the outside world, but must
2383 // instead be copied via ReflectionFactory.copyConstructor.
2384 private Constructor<T>[] privateGetDeclaredConstructors(boolean publicOnly) {
2385 checkInitted();
2386 Constructor<T>[] res = null;
2387 if (useCaches) {
2388 clearCachesOnClassRedefinition();
2389 if (publicOnly) {
2390 if (publicConstructors != null) {
2391 res = publicConstructors.get();
2392 }
2393 } else {
2394 if (declaredConstructors != null) {
2395 res = declaredConstructors.get();
2396 }
2397 }
2398 if (res != null) return res;
2399 }
2400 // No cached value available; request value from VM
2401 if (isInterface()) {
2402 res = new Constructor[0];
2403 } else {
2404 res = getDeclaredConstructors0(publicOnly);
2405 }
2406 if (useCaches) {
2407 if (publicOnly) {
2408 publicConstructors = new SoftReference<>(res);
2409 } else {
2410 declaredConstructors = new SoftReference<>(res);
2411 }
2412 }
2413 return res;
2414 }
2415
2416 //
2417 //
2418 // java.lang.reflect.Method handling
2419 //
2420 //
2421
2422 // Returns an array of "root" methods. These Method objects must NOT
2423 // be propagated to the outside world, but must instead be copied
2424 // via ReflectionFactory.copyMethod.
2425 private Method[] privateGetDeclaredMethods(boolean publicOnly) {
2426 checkInitted();
2427 Method[] res = null;
2428 if (useCaches) {
2429 clearCachesOnClassRedefinition();
2430 if (publicOnly) {
2431 if (declaredPublicMethods != null) {
2432 res = declaredPublicMethods.get();
2433 }
2434 } else {
2435 if (declaredMethods != null) {
2436 res = declaredMethods.get();
2437 }
2438 }
2439 if (res != null) return res;
2440 }
2441 // No cached value available; request value from VM
2442 res = Reflection.filterMethods(this, getDeclaredMethods0(publicOnly));
2443 if (useCaches) {
2444 if (publicOnly) {
2445 declaredPublicMethods = new SoftReference<>(res);
2446 } else {
2447 declaredMethods = new SoftReference<>(res);
2448 }
2449 }
2450 return res;
2451 }
2452
2453 static class MethodArray {
2454 private Method[] methods;
2455 private int length;
2456
2457 MethodArray() {
2458 methods = new Method[20];
2459 length = 0;
2460 }
2461
2462 void add(Method m) {
2463 if (length == methods.length) {
2464 methods = Arrays.copyOf(methods, 2 * methods.length);
2465 }
2466 methods[length++] = m;
2467 }
2468
2469 void addAll(Method[] ma) {
2470 for (int i = 0; i < ma.length; i++) {
2471 add(ma[i]);
2472 }
2473 }
2474
2475 void addAll(MethodArray ma) {
2476 for (int i = 0; i < ma.length(); i++) {
2477 add(ma.get(i));
2478 }
2479 }
2480
2481 void addIfNotPresent(Method newMethod) {
2482 for (int i = 0; i < length; i++) {
2483 Method m = methods[i];
2484 if (m == newMethod || (m != null && m.equals(newMethod))) {
2485 return;
2486 }
2487 }
2488 add(newMethod);
2489 }
2490
2491 void addAllIfNotPresent(MethodArray newMethods) {
2492 for (int i = 0; i < newMethods.length(); i++) {
2493 Method m = newMethods.get(i);
2494 if (m != null) {
2495 addIfNotPresent(m);
2496 }
2497 }
2498 }
2499
2500 int length() {
2501 return length;
2502 }
2503
2504 Method get(int i) {
2505 return methods[i];
2506 }
2507
2508 void removeByNameAndSignature(Method toRemove) {
2509 for (int i = 0; i < length; i++) {
2510 Method m = methods[i];
2511 if (m != null &&
2512 m.getReturnType() == toRemove.getReturnType() &&
2513 m.getName() == toRemove.getName() &&
2514 arrayContentsEq(m.getParameterTypes(),
2515 toRemove.getParameterTypes())) {
2516 methods[i] = null;
2517 }
2518 }
2519 }
2520
2521 void compactAndTrim() {
2522 int newPos = 0;
2523 // Get rid of null slots
2524 for (int pos = 0; pos < length; pos++) {
2525 Method m = methods[pos];
2526 if (m != null) {
2527 if (pos != newPos) {
2528 methods[newPos] = m;
2529 }
2530 newPos++;
2531 }
2532 }
2533 if (newPos != methods.length) {
2534 methods = Arrays.copyOf(methods, newPos);
2535 }
2536 }
2537
2538 Method[] getArray() {
2539 return methods;
2540 }
2541 }
2542
2543
2544 // Returns an array of "root" methods. These Method objects must NOT
2545 // be propagated to the outside world, but must instead be copied
2546 // via ReflectionFactory.copyMethod.
2547 private Method[] privateGetPublicMethods() {
2548 checkInitted();
2549 Method[] res = null;
2550 if (useCaches) {
2551 clearCachesOnClassRedefinition();
2552 if (publicMethods != null) {
2553 res = publicMethods.get();
2554 }
2555 if (res != null) return res;
2556 }
2557
2558 // No cached value available; compute value recursively.
2559 // Start by fetching public declared methods
2560 MethodArray methods = new MethodArray();
2561 {
2562 Method[] tmp = privateGetDeclaredMethods(true);
2563 methods.addAll(tmp);
2564 }
2565 // Now recur over superclass and direct superinterfaces.
2566 // Go over superinterfaces first so we can more easily filter
2567 // out concrete implementations inherited from superclasses at
2568 // the end.
2569 MethodArray inheritedMethods = new MethodArray();
2570 Class<?>[] interfaces = getInterfaces();
2571 for (int i = 0; i < interfaces.length; i++) {
2572 inheritedMethods.addAll(interfaces[i].privateGetPublicMethods());
2573 }
2574 if (!isInterface()) {
2575 Class<?> c = getSuperclass();
2576 if (c != null) {
2577 MethodArray supers = new MethodArray();
2578 supers.addAll(c.privateGetPublicMethods());
2579 // Filter out concrete implementations of any
2580 // interface methods
2581 for (int i = 0; i < supers.length(); i++) {
2582 Method m = supers.get(i);
2583 if (m != null && !Modifier.isAbstract(m.getModifiers())) {
2584 inheritedMethods.removeByNameAndSignature(m);
2585 }
2586 }
2587 // Insert superclass's inherited methods before
2588 // superinterfaces' to satisfy getMethod's search
2589 // order
2590 supers.addAll(inheritedMethods);
2591 inheritedMethods = supers;
2592 }
2593 }
2594 // Filter out all local methods from inherited ones
2595 for (int i = 0; i < methods.length(); i++) {
2596 Method m = methods.get(i);
2597 inheritedMethods.removeByNameAndSignature(m);
2598 }
2599 methods.addAllIfNotPresent(inheritedMethods);
2600 methods.compactAndTrim();
2601 res = methods.getArray();
2602 if (useCaches) {
2603 publicMethods = new SoftReference<>(res);
2604 }
2605 return res;
2606 }
2607
2608
2609 //
2610 // Helpers for fetchers of one field, method, or constructor
2611 //
2612
2613 private Field searchFields(Field[] fields, String name) {
2614 String internedName = name.intern();
2615 for (int i = 0; i < fields.length; i++) {
2616 if (fields[i].getName() == internedName) {
2617 return getReflectionFactory().copyField(fields[i]);
2618 }
2619 }
2620 return null;
2621 }
2622
2623 private Field getField0(String name) throws NoSuchFieldException {
2624 // Note: the intent is that the search algorithm this routine
2625 // uses be equivalent to the ordering imposed by
2626 // privateGetPublicFields(). It fetches only the declared
2627 // public fields for each class, however, to reduce the number
2628 // of Field objects which have to be created for the common
2629 // case where the field being requested is declared in the
2630 // class which is being queried.
2631 Field res = null;
2632 // Search declared public fields
2633 if ((res = searchFields(privateGetDeclaredFields(true), name)) != null) {
2634 return res;
2635 }
2636 // Direct superinterfaces, recursively
2637 Class<?>[] interfaces = getInterfaces();
2638 for (int i = 0; i < interfaces.length; i++) {
2639 Class<?> c = interfaces[i];
2640 if ((res = c.getField0(name)) != null) {
2641 return res;
2642 }
2643 }
2644 // Direct superclass, recursively
2645 if (!isInterface()) {
2646 Class<?> c = getSuperclass();
2647 if (c != null) {
2648 if ((res = c.getField0(name)) != null) {
2649 return res;
2650 }
2651 }
2652 }
2653 return null;
2654 }
2655
2656 private static Method searchMethods(Method[] methods,
2657 String name,
2658 Class<?>[] parameterTypes)
2659 {
2660 Method res = null;
2661 String internedName = name.intern();
2662 for (int i = 0; i < methods.length; i++) {
2663 Method m = methods[i];
2664 if (m.getName() == internedName
2665 && arrayContentsEq(parameterTypes, m.getParameterTypes())
2666 && (res == null
2667 || res.getReturnType().isAssignableFrom(m.getReturnType())))
2668 res = m;
2669 }
2670
2671 return (res == null ? res : getReflectionFactory().copyMethod(res));
2672 }
2673
2674
2675 private Method getMethod0(String name, Class<?>[] parameterTypes) {
2676 // Note: the intent is that the search algorithm this routine
2677 // uses be equivalent to the ordering imposed by
2678 // privateGetPublicMethods(). It fetches only the declared
2679 // public methods for each class, however, to reduce the
2680 // number of Method objects which have to be created for the
2681 // common case where the method being requested is declared in
2682 // the class which is being queried.
2683 Method res = null;
2684 // Search declared public methods
2685 if ((res = searchMethods(privateGetDeclaredMethods(true),
2686 name,
2687 parameterTypes)) != null) {
2688 return res;
2689 }
2690 // Search superclass's methods
2691 if (!isInterface()) {
2692 Class<? super T> c = getSuperclass();
2693 if (c != null) {
2694 if ((res = c.getMethod0(name, parameterTypes)) != null) {
2695 return res;
2696 }
2697 }
2698 }
2699 // Search superinterfaces' methods
2700 Class<?>[] interfaces = getInterfaces();
2701 for (int i = 0; i < interfaces.length; i++) {
2702 Class<?> c = interfaces[i];
2703 if ((res = c.getMethod0(name, parameterTypes)) != null) {
2704 return res;
2705 }
2706 }
2707 // Not found
2708 return null;
2709 }
2710
2711 private Constructor<T> getConstructor0(Class<?>[] parameterTypes,
2712 int which) throws NoSuchMethodException
2713 {
2714 Constructor<T>[] constructors = privateGetDeclaredConstructors((which == Member.PUBLIC));
2715 for (Constructor<T> constructor : constructors) {
2716 if (arrayContentsEq(parameterTypes,
2717 constructor.getParameterTypes())) {
2718 return getReflectionFactory().copyConstructor(constructor);
2719 }
2720 }
2721 throw new NoSuchMethodException(getName() + ".<init>" + argumentTypesToString(parameterTypes));
2722 }
2723
2724 //
2725 // Other helpers and base implementation
2726 //
2727
2728 private static boolean arrayContentsEq(Object[] a1, Object[] a2) {
2729 if (a1 == null) {
2730 return a2 == null || a2.length == 0;
2731 }
2732
2733 if (a2 == null) {
2734 return a1.length == 0;
2735 }
2736
2737 if (a1.length != a2.length) {
2738 return false;
2739 }
2740
2741 for (int i = 0; i < a1.length; i++) {
2742 if (a1[i] != a2[i]) {
2743 return false;
2744 }
2745 }
2746
2747 return true;
2748 }
2749
2750 private static Field[] copyFields(Field[] arg) {
2751 Field[] out = new Field[arg.length];
2752 ReflectionFactory fact = getReflectionFactory();
2753 for (int i = 0; i < arg.length; i++) {
2754 out[i] = fact.copyField(arg[i]);
2755 }
2756 return out;
2757 }
2758
2759 private static Method[] copyMethods(Method[] arg) {
2760 Method[] out = new Method[arg.length];
2761 ReflectionFactory fact = getReflectionFactory();
2762 for (int i = 0; i < arg.length; i++) {
2763 out[i] = fact.copyMethod(arg[i]);
2764 }
2765 return out;
2766 }
2767
2768 private static <U> Constructor<U>[] copyConstructors(Constructor<U>[] arg) {
2769 Constructor<U>[] out = arg.clone();
2770 ReflectionFactory fact = getReflectionFactory();
2771 for (int i = 0; i < out.length; i++) {
2772 out[i] = fact.copyConstructor(out[i]);
2773 }
2774 return out;
2775 }
2776
2777 private native Field[] getDeclaredFields0(boolean publicOnly);
2778 private native Method[] getDeclaredMethods0(boolean publicOnly);
2779 private native Constructor<T>[] getDeclaredConstructors0(boolean publicOnly);
2780 private native Class<?>[] getDeclaredClasses0();
2781
2782 private static String argumentTypesToString(Class<?>[] argTypes) {
2783 StringBuilder buf = new StringBuilder();
2784 buf.append("(");
2785 if (argTypes != null) {
2786 for (int i = 0; i < argTypes.length; i++) {
2787 if (i > 0) {
2788 buf.append(", ");
2789 }
2790 Class<?> c = argTypes[i];
2791 buf.append((c == null) ? "null" : c.getName());
2792 }
2793 }
2794 buf.append(")");
2795 return buf.toString();
2796 }
2797
2798 /** use serialVersionUID from JDK 1.1 for interoperability */
2799 private static final long serialVersionUID = 3206093459760846163L;
2800
2801
2802 /**
2803 * Class Class is special cased within the Serialization Stream Protocol.
2804 *
2805 * A Class instance is written initially into an ObjectOutputStream in the
2806 * following format:
2807 * <pre>
2808 * {@code TC_CLASS} ClassDescriptor
2809 * A ClassDescriptor is a special cased serialization of
2810 * a {@code java.io.ObjectStreamClass} instance.
2811 * </pre>
2812 * A new handle is generated for the initial time the class descriptor
2813 * is written into the stream. Future references to the class descriptor
2814 * are written as references to the initial class descriptor instance.
2815 *
2816 * @see java.io.ObjectStreamClass
2817 */
2818 private static final ObjectStreamField[] serialPersistentFields =
2819 new ObjectStreamField[0];
2820
2821
2822 /**
2823 * Returns the assertion status that would be assigned to this
2824 * class if it were to be initialized at the time this method is invoked.
2825 * If this class has had its assertion status set, the most recent
2826 * setting will be returned; otherwise, if any package default assertion
2827 * status pertains to this class, the most recent setting for the most
2828 * specific pertinent package default assertion status is returned;
2829 * otherwise, if this class is not a system class (i.e., it has a
2830 * class loader) its class loader's default assertion status is returned;
2831 * otherwise, the system class default assertion status is returned.
2832 * <p>
2833 * Few programmers will have any need for this method; it is provided
2834 * for the benefit of the JRE itself. (It allows a class to determine at
2835 * the time that it is initialized whether assertions should be enabled.)
2836 * Note that this method is not guaranteed to return the actual
2837 * assertion status that was (or will be) associated with the specified
2838 * class when it was (or will be) initialized.
2839 *
2840 * @return the desired assertion status of the specified class.
2841 * @see java.lang.ClassLoader#setClassAssertionStatus
2842 * @see java.lang.ClassLoader#setPackageAssertionStatus
2843 * @see java.lang.ClassLoader#setDefaultAssertionStatus
2844 * @since 1.4
2845 */
2846 public boolean desiredAssertionStatus() {
2847 ClassLoader loader = getClassLoader();
2848 // If the loader is null this is a system class, so ask the VM
2849 if (loader == null)
2850 return desiredAssertionStatus0(this);
2851
2852 // If the classloader has been initialized with the assertion
2853 // directives, ask it. Otherwise, ask the VM.
2854 synchronized(loader.assertionLock) {
2855 if (loader.classAssertionStatus != null) {
2856 return loader.desiredAssertionStatus(getName());
2857 }
2858 }
2859 return desiredAssertionStatus0(this);
2860 }
2861
2862 // Retrieves the desired assertion status of this class from the VM
2863 private static native boolean desiredAssertionStatus0(Class<?> clazz);
2864
2865 /**
2866 * Returns true if and only if this class was declared as an enum in the
2867 * source code.
2868 *
2869 * @return true if and only if this class was declared as an enum in the
2870 * source code
2871 * @since 1.5
2872 */
2873 public boolean isEnum() {
2874 // An enum must both directly extend java.lang.Enum and have
2875 // the ENUM bit set; classes for specialized enum constants
2876 // don't do the former.
2877 return (this.getModifiers() & ENUM) != 0 &&
2878 this.getSuperclass() == java.lang.Enum.class;
2879 }
2880
2881 // Fetches the factory for reflective objects
2882 private static ReflectionFactory getReflectionFactory() {
2883 if (reflectionFactory == null) {
2884 reflectionFactory =
2885 java.security.AccessController.doPrivileged
2886 (new sun.reflect.ReflectionFactory.GetReflectionFactoryAction());
2887 }
2888 return reflectionFactory;
2889 }
2890 private static ReflectionFactory reflectionFactory;
2891
2892 // To be able to query system properties as soon as they're available
2893 private static boolean initted = false;
2894 private static void checkInitted() {
2895 if (initted) return;
2896 AccessController.doPrivileged(new PrivilegedAction<Void>() {
2897 public Void run() {
2898 // Tests to ensure the system properties table is fully
2899 // initialized. This is needed because reflection code is
2900 // called very early in the initialization process (before
2901 // command-line arguments have been parsed and therefore
2902 // these user-settable properties installed.) We assume that
2903 // if System.out is non-null then the System class has been
2904 // fully initialized and that the bulk of the startup code
2905 // has been run.
2906
2907 if (System.out == null) {
2908 // java.lang.System not yet fully initialized
2909 return null;
2910 }
2911
2912 String val =
2913 System.getProperty("sun.reflect.noCaches");
2914 if (val != null && val.equals("true")) {
2915 useCaches = false;
2916 }
2917
2918 initted = true;
2919 return null;
2920 }
2921 });
2922 }
2923
2924 /**
2925 * Returns the elements of this enum class or null if this
2926 * Class object does not represent an enum type.
2927 *
2928 * @return an array containing the values comprising the enum class
2929 * represented by this Class object in the order they're
2930 * declared, or null if this Class object does not
2931 * represent an enum type
2932 * @since 1.5
2933 */
2934 public T[] getEnumConstants() {
2935 T[] values = getEnumConstantsShared();
2936 return (values != null) ? values.clone() : null;
2937 }
2938
2939 /**
2940 * Returns the elements of this enum class or null if this
2941 * Class object does not represent an enum type;
2942 * identical to getEnumConstants except that the result is
2943 * uncloned, cached, and shared by all callers.
2944 */
2945 T[] getEnumConstantsShared() {
2946 if (enumConstants == null) {
2947 if (!isEnum()) return null;
2948 try {
2949 final Method values = getMethod("values");
2950 java.security.AccessController.doPrivileged(
2951 new java.security.PrivilegedAction<Void>() {
2952 public Void run() {
2953 values.setAccessible(true);
2954 return null;
2955 }
2956 });
2957 enumConstants = (T[])values.invoke(null);
2958 }
2959 // These can happen when users concoct enum-like classes
2960 // that don't comply with the enum spec.
2961 catch (InvocationTargetException ex) { return null; }
2962 catch (NoSuchMethodException ex) { return null; }
2963 catch (IllegalAccessException ex) { return null; }
2964 }
2965 return enumConstants;
2966 }
2967 private volatile transient T[] enumConstants = null;
2968
2969 /**
2970 * Returns a map from simple name to enum constant. This package-private
2971 * method is used internally by Enum to implement
2972 * public static <T extends Enum<T>> T valueOf(Class<T>, String)
2973 * efficiently. Note that the map is returned by this method is
2974 * created lazily on first use. Typically it won't ever get created.
2975 */
2976 Map<String, T> enumConstantDirectory() {
2977 if (enumConstantDirectory == null) {
2978 T[] universe = getEnumConstantsShared();
2979 if (universe == null)
2980 throw new IllegalArgumentException(
2981 getName() + " is not an enum type");
2982 Map<String, T> m = new HashMap<>(2 * universe.length);
2983 for (T constant : universe)
2984 m.put(((Enum<?>)constant).name(), constant);
2985 enumConstantDirectory = m;
2986 }
2987 return enumConstantDirectory;
2988 }
2989 private volatile transient Map<String, T> enumConstantDirectory = null;
2990
2991 /**
2992 * Casts an object to the class or interface represented
2993 * by this {@code Class} object.
2994 *
2995 * @param obj the object to be cast
2996 * @return the object after casting, or null if obj is null
2997 *
2998 * @throws ClassCastException if the object is not
2999 * null and is not assignable to the type T.
3000 *
3001 * @since 1.5
3002 */
3003 public T cast(Object obj) {
3004 if (obj != null && !isInstance(obj))
3005 throw new ClassCastException(cannotCastMsg(obj));
3006 return (T) obj;
3007 }
3008
3009 private String cannotCastMsg(Object obj) {
3010 return "Cannot cast " + obj.getClass().getName() + " to " + getName();
3011 }
3012
3013 /**
3014 * Casts this {@code Class} object to represent a subclass of the class
3015 * represented by the specified class object. Checks that that the cast
3016 * is valid, and throws a {@code ClassCastException} if it is not. If
3017 * this method succeeds, it always returns a reference to this class object.
3018 *
3019 * <p>This method is useful when a client needs to "narrow" the type of
3020 * a {@code Class} object to pass it to an API that restricts the
3021 * {@code Class} objects that it is willing to accept. A cast would
3022 * generate a compile-time warning, as the correctness of the cast
3023 * could not be checked at runtime (because generic types are implemented
3024 * by erasure).
3025 *
3026 * @return this {@code Class} object, cast to represent a subclass of
3027 * the specified class object.
3028 * @throws ClassCastException if this {@code Class} object does not
3029 * represent a subclass of the specified class (here "subclass" includes
3030 * the class itself).
3031 * @since 1.5
3032 */
3033 public <U> Class<? extends U> asSubclass(Class<U> clazz) {
3034 if (clazz.isAssignableFrom(this))
3035 return (Class<? extends U>) this;
3036 else
3037 throw new ClassCastException(this.toString());
3038 }
3039
3040 /**
3041 * @throws NullPointerException {@inheritDoc}
3042 * @since 1.5
3043 */
3044 public <A extends Annotation> A getAnnotation(Class<A> annotationClass) {
3045 if (annotationClass == null)
3046 throw new NullPointerException();
3047
3048 initAnnotationsIfNecessary();
3049 return (A) annotations.get(annotationClass);
3050 }
3051
3052 /**
3053 * @throws NullPointerException {@inheritDoc}
3054 * @since 1.5
3055 */
3056 public boolean isAnnotationPresent(
3057 Class<? extends Annotation> annotationClass) {
3058 if (annotationClass == null)
3059 throw new NullPointerException();
3060
3061 return getAnnotation(annotationClass) != null;
3062 }
3063
3064
3065 /**
3066 * @since 1.5
3067 */
3068 public Annotation[] getAnnotations() {
3069 initAnnotationsIfNecessary();
3070 return AnnotationParser.toArray(annotations);
3071 }
3072
3073 /**
3074 * @since 1.5
3075 */
3076 public Annotation[] getDeclaredAnnotations() {
3077 initAnnotationsIfNecessary();
3078 return AnnotationParser.toArray(declaredAnnotations);
3079 }
3080
3081 // Annotations cache
3082 private transient Map<Class<? extends Annotation>, Annotation> annotations;
3083 private transient Map<Class<? extends Annotation>, Annotation> declaredAnnotations;
3084
3085 private synchronized void initAnnotationsIfNecessary() {
3086 clearCachesOnClassRedefinition();
3087 if (annotations != null)
3088 return;
3089 declaredAnnotations = AnnotationParser.parseAnnotations(
3090 getRawAnnotations(), getConstantPool(), this);
3091 Class<?> superClass = getSuperclass();
3092 if (superClass == null) {
3093 annotations = declaredAnnotations;
3094 } else {
3095 annotations = new HashMap<>();
3096 superClass.initAnnotationsIfNecessary();
3097 for (Map.Entry<Class<? extends Annotation>, Annotation> e : superClass.annotations.entrySet()) {
3098 Class<? extends Annotation> annotationClass = e.getKey();
3099 if (AnnotationType.getInstance(annotationClass).isInherited())
3100 annotations.put(annotationClass, e.getValue());
3101 }
3102 annotations.putAll(declaredAnnotations);
3103 }
3104 }
3105
3106 // Annotation types cache their internal (AnnotationType) form
3107
3108 private AnnotationType annotationType;
3109
3110 void setAnnotationType(AnnotationType type) {
3111 annotationType = type;
3112 }
3113
3114 AnnotationType getAnnotationType() {
3115 return annotationType;
3116 }
3117 }
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