1 /*
2 * Copyright (c) 1994, 2019, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package java.lang;
27
28 import java.lang.annotation.Annotation;
29 import java.lang.constant.ClassDesc;
30 import java.lang.invoke.TypeDescriptor;
31 import java.lang.module.ModuleReader;
32 import java.lang.ref.SoftReference;
33 import java.io.IOException;
34 import java.io.InputStream;
35 import java.io.ObjectStreamField;
36 import java.lang.reflect.AnnotatedElement;
37 import java.lang.reflect.AnnotatedType;
38 import java.lang.reflect.Array;
39 import java.lang.reflect.Constructor;
40 import java.lang.reflect.Executable;
41 import java.lang.reflect.Field;
42 import java.lang.reflect.GenericArrayType;
43 import java.lang.reflect.GenericDeclaration;
44 import java.lang.reflect.InvocationTargetException;
45 import java.lang.reflect.Member;
46 import java.lang.reflect.Method;
47 import java.lang.reflect.Modifier;
48 import java.lang.reflect.Proxy;
49 import java.lang.reflect.Type;
50 import java.lang.reflect.TypeVariable;
51 import java.lang.constant.Constable;
52 import java.net.URL;
53 import java.security.AccessController;
54 import java.security.PrivilegedAction;
55 import java.util.ArrayList;
56 import java.util.Arrays;
57 import java.util.Collection;
58 import java.util.HashMap;
59 import java.util.LinkedHashMap;
60 import java.util.LinkedHashSet;
61 import java.util.List;
62 import java.util.Map;
63 import java.util.Objects;
64 import java.util.Optional;
65 import java.util.StringJoiner;
66 import java.util.stream.Stream;
67 import java.util.stream.Collectors;
68
69 import jdk.internal.HotSpotIntrinsicCandidate;
70 import jdk.internal.loader.BootLoader;
71 import jdk.internal.loader.BuiltinClassLoader;
72 import jdk.internal.misc.Unsafe;
73 import jdk.internal.module.Resources;
74 import jdk.internal.reflect.CallerSensitive;
75 import jdk.internal.reflect.ConstantPool;
76 import jdk.internal.reflect.Reflection;
77 import jdk.internal.reflect.ReflectionFactory;
78 import jdk.internal.vm.annotation.ForceInline;
79 import sun.invoke.util.Wrapper;
80 import sun.reflect.generics.factory.CoreReflectionFactory;
81 import sun.reflect.generics.factory.GenericsFactory;
82 import sun.reflect.generics.repository.ClassRepository;
83 import sun.reflect.generics.repository.MethodRepository;
84 import sun.reflect.generics.repository.ConstructorRepository;
85 import sun.reflect.generics.scope.ClassScope;
86 import sun.security.util.SecurityConstants;
87 import sun.reflect.annotation.*;
88 import sun.reflect.misc.ReflectUtil;
89
90 /**
91 * Instances of the class {@code Class} represent classes and interfaces
92 * in a running Java application. An enum type is a kind of class and an
93 * annotation type is a kind of interface. Every array also
94 * belongs to a class that is reflected as a {@code Class} object
95 * that is shared by all arrays with the same element type and number
96 * of dimensions. The primitive Java types ({@code boolean},
97 * {@code byte}, {@code char}, {@code short},
98 * {@code int}, {@code long}, {@code float}, and
99 * {@code double}), and the keyword {@code void} are also
100 * represented as {@code Class} objects.
101 *
102 * <p> {@code Class} has no public constructor. Instead a {@code Class}
103 * object is constructed automatically by the Java Virtual Machine
104 * when a class loader invokes one of the
105 * {@link ClassLoader#defineClass(String,byte[], int,int) defineClass} methods
106 * and passes the bytes of a {@code class} file.
107 *
108 * <p> The methods of class {@code Class} expose many characteristics of a
109 * class or interface. Most characteristics are derived from the {@code class}
110 * file that the class loader passed to the Java Virtual Machine. A few
111 * characteristics are determined by the class loading environment at run time,
112 * such as the module returned by {@link #getModule() getModule()}.
113 *
114 * <p> Some methods of class {@code Class} expose whether the declaration of
115 * a class or interface in Java source code was <em>enclosed</em> within
116 * another declaration. Other methods describe how a class or interface
117 * is situated in a <em>nest</em>. A <a id="nest">nest</a> is a set of
118 * classes and interfaces, in the same run-time package, that
119 * allow mutual access to their {@code private} members.
120 * The classes and interfaces are known as <em>nestmates</em>.
121 * One nestmate acts as the
122 * <em>nest host</em>, and enumerates the other nestmates which
123 * belong to the nest; each of them in turn records it as the nest host.
124 * The classes and interfaces which belong to a nest, including its host, are
125 * determined when
126 * {@code class} files are generated, for example, a Java compiler
127 * will typically record a top-level class as the host of a nest where the
128 * other members are the classes and interfaces whose declarations are
129 * enclosed within the top-level class declaration.
130 *
131 * <p> The following example uses a {@code Class} object to print the
132 * class name of an object:
133 *
134 * <blockquote><pre>
135 * void printClassName(Object obj) {
136 * System.out.println("The class of " + obj +
137 * " is " + obj.getClass().getName());
138 * }
139 * </pre></blockquote>
140 *
141 * <p> It is also possible to get the {@code Class} object for a named
142 * type (or for void) using a class literal. See Section 15.8.2 of
143 * <cite>The Java™ Language Specification</cite>.
144 * For example:
145 *
146 * <blockquote>
147 * {@code System.out.println("The name of class Foo is: "+Foo.class.getName());}
148 * </blockquote>
149 *
150 * @param <T> the type of the class modeled by this {@code Class}
151 * object. For example, the type of {@code String.class} is {@code
152 * Class<String>}. Use {@code Class<?>} if the class being modeled is
153 * unknown.
154 *
155 * @author unascribed
156 * @see java.lang.ClassLoader#defineClass(byte[], int, int)
157 * @since 1.0
158 */
159 public final class Class<T> implements java.io.Serializable,
160 GenericDeclaration,
161 Type,
162 AnnotatedElement,
163 TypeDescriptor.OfField<Class<?>>,
164 Constable {
165 private static final int ANNOTATION= 0x00002000;
166 private static final int ENUM = 0x00004000;
167 private static final int SYNTHETIC = 0x00001000;
168
169 private static native void registerNatives();
170 static {
171 registerNatives();
172 }
173
174 /*
175 * Private constructor. Only the Java Virtual Machine creates Class objects.
176 * This constructor is not used and prevents the default constructor being
177 * generated.
178 */
179 private Class(ClassLoader loader, Class<?> arrayComponentType) {
180 // Initialize final field for classLoader. The initialization value of non-null
181 // prevents future JIT optimizations from assuming this final field is null.
182 classLoader = loader;
183 componentType = arrayComponentType;
184 }
185
186 /**
187 * Converts the object to a string. The string representation is the
188 * string "class" or "interface", followed by a space, and then by the
189 * fully qualified name of the class in the format returned by
190 * {@code getName}. If this {@code Class} object represents a
191 * primitive type, this method returns the name of the primitive type. If
192 * this {@code Class} object represents void this method returns
193 * "void". If this {@code Class} object represents an array type,
194 * this method returns "class " followed by {@code getName}.
195 *
196 * @return a string representation of this class object.
197 */
198 public String toString() {
199 return (isInterface() ? "interface " : (isPrimitive() ? "" : "class "))
200 + getName();
201 }
202
203 /**
204 * Returns a string describing this {@code Class}, including
205 * information about modifiers and type parameters.
206 *
207 * The string is formatted as a list of type modifiers, if any,
208 * followed by the kind of type (empty string for primitive types
209 * and {@code class}, {@code enum}, {@code interface}, or
210 * <code>@</code>{@code interface}, as appropriate), followed
211 * by the type's name, followed by an angle-bracketed
212 * comma-separated list of the type's type parameters, if any,
213 * including informative bounds on the type parameters, if any.
214 *
215 * A space is used to separate modifiers from one another and to
216 * separate any modifiers from the kind of type. The modifiers
217 * occur in canonical order. If there are no type parameters, the
218 * type parameter list is elided.
219 *
220 * For an array type, the string starts with the type name,
221 * followed by an angle-bracketed comma-separated list of the
222 * type's type parameters, if any, followed by a sequence of
223 * {@code []} characters, one set of brackets per dimension of
224 * the array.
225 *
226 * <p>Note that since information about the runtime representation
227 * of a type is being generated, modifiers not present on the
228 * originating source code or illegal on the originating source
229 * code may be present.
230 *
231 * @return a string describing this {@code Class}, including
232 * information about modifiers and type parameters
233 *
234 * @since 1.8
235 */
236 public String toGenericString() {
237 if (isPrimitive()) {
238 return toString();
239 } else {
240 StringBuilder sb = new StringBuilder();
241 Class<?> component = this;
242 int arrayDepth = 0;
243
244 if (isArray()) {
245 do {
246 arrayDepth++;
247 component = component.getComponentType();
248 } while (component.isArray());
249 sb.append(component.getName());
250 } else {
251 // Class modifiers are a superset of interface modifiers
252 int modifiers = getModifiers() & Modifier.classModifiers();
253 if (modifiers != 0) {
254 sb.append(Modifier.toString(modifiers));
255 sb.append(' ');
256 }
257
258 if (isAnnotation()) {
259 sb.append('@');
260 }
261 if (isInterface()) { // Note: all annotation types are interfaces
262 sb.append("interface");
263 } else {
264 if (isEnum())
265 sb.append("enum");
266 else
267 sb.append("class");
268 }
269 sb.append(' ');
270 sb.append(getName());
271 }
272
273 TypeVariable<?>[] typeparms = component.getTypeParameters();
274 if (typeparms.length > 0) {
275 sb.append(Arrays.stream(typeparms)
276 .map(Class::typeVarBounds)
277 .collect(Collectors.joining(",", "<", ">")));
278 }
279
280 for (int i = 0; i < arrayDepth; i++)
281 sb.append("[]");
282
283 return sb.toString();
284 }
285 }
286
287 static String typeVarBounds(TypeVariable<?> typeVar) {
288 Type[] bounds = typeVar.getBounds();
289 if (bounds.length == 1 && bounds[0].equals(Object.class)) {
290 return typeVar.getName();
291 } else {
292 return typeVar.getName() + " extends " +
293 Arrays.stream(bounds)
294 .map(Type::getTypeName)
295 .collect(Collectors.joining(" & "));
296 }
297 }
298
299 /**
300 * Returns the {@code Class} object associated with the class or
301 * interface with the given string name. Invoking this method is
302 * equivalent to:
303 *
304 * <blockquote>
305 * {@code Class.forName(className, true, currentLoader)}
306 * </blockquote>
307 *
308 * where {@code currentLoader} denotes the defining class loader of
309 * the current class.
310 *
311 * <p> For example, the following code fragment returns the
312 * runtime {@code Class} descriptor for the class named
313 * {@code java.lang.Thread}:
314 *
315 * <blockquote>
316 * {@code Class t = Class.forName("java.lang.Thread")}
317 * </blockquote>
318 * <p>
319 * A call to {@code forName("X")} causes the class named
320 * {@code X} to be initialized.
321 *
322 * @param className the fully qualified name of the desired class.
323 * @return the {@code Class} object for the class with the
324 * specified name.
325 * @exception LinkageError if the linkage fails
326 * @exception ExceptionInInitializerError if the initialization provoked
327 * by this method fails
328 * @exception ClassNotFoundException if the class cannot be located
329 */
330 @CallerSensitive
331 public static Class<?> forName(String className)
332 throws ClassNotFoundException {
333 Class<?> caller = Reflection.getCallerClass();
334 return forName0(className, true, ClassLoader.getClassLoader(caller), caller);
335 }
336
337
338 /**
339 * Returns the {@code Class} object associated with the class or
340 * interface with the given string name, using the given class loader.
341 * Given the fully qualified name for a class or interface (in the same
342 * format returned by {@code getName}) this method attempts to
343 * locate, load, and link the class or interface. The specified class
344 * loader is used to load the class or interface. If the parameter
345 * {@code loader} is null, the class is loaded through the bootstrap
346 * class loader. The class is initialized only if the
347 * {@code initialize} parameter is {@code true} and if it has
348 * not been initialized earlier.
349 *
350 * <p> If {@code name} denotes a primitive type or void, an attempt
351 * will be made to locate a user-defined class in the unnamed package whose
352 * name is {@code name}. Therefore, this method cannot be used to
353 * obtain any of the {@code Class} objects representing primitive
354 * types or void.
355 *
356 * <p> If {@code name} denotes an array class, the component type of
357 * the array class is loaded but not initialized.
358 *
359 * <p> For example, in an instance method the expression:
360 *
361 * <blockquote>
362 * {@code Class.forName("Foo")}
363 * </blockquote>
364 *
365 * is equivalent to:
366 *
367 * <blockquote>
368 * {@code Class.forName("Foo", true, this.getClass().getClassLoader())}
369 * </blockquote>
370 *
371 * Note that this method throws errors related to loading, linking or
372 * initializing as specified in Sections 12.2, 12.3 and 12.4 of <em>The
373 * Java Language Specification</em>.
374 * Note that this method does not check whether the requested class
375 * is accessible to its caller.
376 *
377 * @param name fully qualified name of the desired class
378 * @param initialize if {@code true} the class will be initialized.
379 * See Section 12.4 of <em>The Java Language Specification</em>.
380 * @param loader class loader from which the class must be loaded
381 * @return class object representing the desired class
382 *
383 * @exception LinkageError if the linkage fails
384 * @exception ExceptionInInitializerError if the initialization provoked
385 * by this method fails
386 * @exception ClassNotFoundException if the class cannot be located by
387 * the specified class loader
388 * @exception SecurityException
389 * if a security manager is present, and the {@code loader} is
390 * {@code null}, and the caller's class loader is not
391 * {@code null}, and the caller does not have the
392 * {@link RuntimePermission}{@code ("getClassLoader")}
393 *
394 * @see java.lang.Class#forName(String)
395 * @see java.lang.ClassLoader
396 * @since 1.2
397 */
398 @CallerSensitive
399 public static Class<?> forName(String name, boolean initialize,
400 ClassLoader loader)
401 throws ClassNotFoundException
402 {
403 Class<?> caller = null;
404 SecurityManager sm = System.getSecurityManager();
405 if (sm != null) {
406 // Reflective call to get caller class is only needed if a security manager
407 // is present. Avoid the overhead of making this call otherwise.
408 caller = Reflection.getCallerClass();
409 if (loader == null) {
410 ClassLoader ccl = ClassLoader.getClassLoader(caller);
411 if (ccl != null) {
412 sm.checkPermission(
413 SecurityConstants.GET_CLASSLOADER_PERMISSION);
414 }
415 }
416 }
417 return forName0(name, initialize, loader, caller);
418 }
419
420 /** Called after security check for system loader access checks have been made. */
421 private static native Class<?> forName0(String name, boolean initialize,
422 ClassLoader loader,
423 Class<?> caller)
424 throws ClassNotFoundException;
425
426
427 /**
428 * Returns the {@code Class} with the given <a href="ClassLoader.html#binary-name">
429 * binary name</a> in the given module.
430 *
431 * <p> This method attempts to locate, load, and link the class or interface.
432 * It does not run the class initializer. If the class is not found, this
433 * method returns {@code null}. </p>
434 *
435 * <p> If the class loader of the given module defines other modules and
436 * the given name is a class defined in a different module, this method
437 * returns {@code null} after the class is loaded. </p>
438 *
439 * <p> This method does not check whether the requested class is
440 * accessible to its caller. </p>
441 *
442 * @apiNote
443 * This method returns {@code null} on failure rather than
444 * throwing a {@link ClassNotFoundException}, as is done by
445 * the {@link #forName(String, boolean, ClassLoader)} method.
446 * The security check is a stack-based permission check if the caller
447 * loads a class in another module.
448 *
449 * @param module A module
450 * @param name The <a href="ClassLoader.html#binary-name">binary name</a>
451 * of the class
452 * @return {@code Class} object of the given name defined in the given module;
453 * {@code null} if not found.
454 *
455 * @throws NullPointerException if the given module or name is {@code null}
456 *
457 * @throws LinkageError if the linkage fails
458 *
459 * @throws SecurityException
460 * <ul>
461 * <li> if the caller is not the specified module and
462 * {@code RuntimePermission("getClassLoader")} permission is denied; or</li>
463 * <li> access to the module content is denied. For example,
464 * permission check will be performed when a class loader calls
465 * {@link ModuleReader#open(String)} to read the bytes of a class file
466 * in a module.</li>
467 * </ul>
468 *
469 * @since 9
470 * @spec JPMS
471 */
472 @CallerSensitive
473 public static Class<?> forName(Module module, String name) {
474 Objects.requireNonNull(module);
475 Objects.requireNonNull(name);
476
477 ClassLoader cl;
478 SecurityManager sm = System.getSecurityManager();
479 if (sm != null) {
480 Class<?> caller = Reflection.getCallerClass();
481 if (caller != null && caller.getModule() != module) {
482 // if caller is null, Class.forName is the last java frame on the stack.
483 // java.base has all permissions
484 sm.checkPermission(SecurityConstants.GET_CLASSLOADER_PERMISSION);
485 }
486 PrivilegedAction<ClassLoader> pa = module::getClassLoader;
487 cl = AccessController.doPrivileged(pa);
488 } else {
489 cl = module.getClassLoader();
490 }
491
492 if (cl != null) {
493 return cl.loadClass(module, name);
494 } else {
495 return BootLoader.loadClass(module, name);
496 }
497 }
498
499 /**
500 * Creates a new instance of the class represented by this {@code Class}
501 * object. The class is instantiated as if by a {@code new}
502 * expression with an empty argument list. The class is initialized if it
503 * has not already been initialized.
504 *
505 * @deprecated This method propagates any exception thrown by the
506 * nullary constructor, including a checked exception. Use of
507 * this method effectively bypasses the compile-time exception
508 * checking that would otherwise be performed by the compiler.
509 * The {@link
510 * java.lang.reflect.Constructor#newInstance(java.lang.Object...)
511 * Constructor.newInstance} method avoids this problem by wrapping
512 * any exception thrown by the constructor in a (checked) {@link
513 * java.lang.reflect.InvocationTargetException}.
514 *
515 * <p>The call
516 *
517 * <pre>{@code
518 * clazz.newInstance()
519 * }</pre>
520 *
521 * can be replaced by
522 *
523 * <pre>{@code
524 * clazz.getDeclaredConstructor().newInstance()
525 * }</pre>
526 *
527 * The latter sequence of calls is inferred to be able to throw
528 * the additional exception types {@link
529 * InvocationTargetException} and {@link
530 * NoSuchMethodException}. Both of these exception types are
531 * subclasses of {@link ReflectiveOperationException}.
532 *
533 * @return a newly allocated instance of the class represented by this
534 * object.
535 * @throws IllegalAccessException if the class or its nullary
536 * constructor is not accessible.
537 * @throws InstantiationException
538 * if this {@code Class} represents an abstract class,
539 * an interface, an array class, a primitive type, or void;
540 * or if the class has no nullary constructor;
541 * or if the instantiation fails for some other reason.
542 * @throws ExceptionInInitializerError if the initialization
543 * provoked by this method fails.
544 * @throws SecurityException
545 * If a security manager, <i>s</i>, is present and
546 * the caller's class loader is not the same as or an
547 * ancestor of the class loader for the current class and
548 * invocation of {@link SecurityManager#checkPackageAccess
549 * s.checkPackageAccess()} denies access to the package
550 * of this class.
551 */
552 @CallerSensitive
553 @Deprecated(since="9")
554 public T newInstance()
555 throws InstantiationException, IllegalAccessException
556 {
557 SecurityManager sm = System.getSecurityManager();
558 if (sm != null) {
559 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), false);
560 }
561
562 // Constructor lookup
563 Constructor<T> tmpConstructor = cachedConstructor;
564 if (tmpConstructor == null) {
565 if (this == Class.class) {
566 throw new IllegalAccessException(
567 "Can not call newInstance() on the Class for java.lang.Class"
568 );
569 }
570 try {
571 Class<?>[] empty = {};
572 final Constructor<T> c = getReflectionFactory().copyConstructor(
573 getConstructor0(empty, Member.DECLARED));
574 // Disable accessibility checks on the constructor
575 // access check is done with the true caller
576 java.security.AccessController.doPrivileged(
577 new java.security.PrivilegedAction<>() {
578 public Void run() {
579 c.setAccessible(true);
580 return null;
581 }
582 });
583 cachedConstructor = tmpConstructor = c;
584 } catch (NoSuchMethodException e) {
585 throw (InstantiationException)
586 new InstantiationException(getName()).initCause(e);
587 }
588 }
589
590 try {
591 Class<?> caller = Reflection.getCallerClass();
592 return getReflectionFactory().newInstance(tmpConstructor, null, caller);
593 } catch (InvocationTargetException e) {
594 Unsafe.getUnsafe().throwException(e.getTargetException());
595 // Not reached
596 return null;
597 }
598 }
599
600 private transient volatile Constructor<T> cachedConstructor;
601
602 /**
603 * Determines if the specified {@code Object} is assignment-compatible
604 * with the object represented by this {@code Class}. This method is
605 * the dynamic equivalent of the Java language {@code instanceof}
606 * operator. The method returns {@code true} if the specified
607 * {@code Object} argument is non-null and can be cast to the
608 * reference type represented by this {@code Class} object without
609 * raising a {@code ClassCastException.} It returns {@code false}
610 * otherwise.
611 *
612 * <p> Specifically, if this {@code Class} object represents a
613 * declared class, this method returns {@code true} if the specified
614 * {@code Object} argument is an instance of the represented class (or
615 * of any of its subclasses); it returns {@code false} otherwise. If
616 * this {@code Class} object represents an array class, this method
617 * returns {@code true} if the specified {@code Object} argument
618 * can be converted to an object of the array class by an identity
619 * conversion or by a widening reference conversion; it returns
620 * {@code false} otherwise. If this {@code Class} object
621 * represents an interface, this method returns {@code true} if the
622 * class or any superclass of the specified {@code Object} argument
623 * implements this interface; it returns {@code false} otherwise. If
624 * this {@code Class} object represents a primitive type, this method
625 * returns {@code false}.
626 *
627 * @param obj the object to check
628 * @return true if {@code obj} is an instance of this class
629 *
630 * @since 1.1
631 */
632 @HotSpotIntrinsicCandidate
633 public native boolean isInstance(Object obj);
634
635
636 /**
637 * Determines if the class or interface represented by this
638 * {@code Class} object is either the same as, or is a superclass or
639 * superinterface of, the class or interface represented by the specified
640 * {@code Class} parameter. It returns {@code true} if so;
641 * otherwise it returns {@code false}. If this {@code Class}
642 * object represents a primitive type, this method returns
643 * {@code true} if the specified {@code Class} parameter is
644 * exactly this {@code Class} object; otherwise it returns
645 * {@code false}.
646 *
647 * <p> Specifically, this method tests whether the type represented by the
648 * specified {@code Class} parameter can be converted to the type
649 * represented by this {@code Class} object via an identity conversion
650 * or via a widening reference conversion. See <em>The Java Language
651 * Specification</em>, sections 5.1.1 and 5.1.4 , for details.
652 *
653 * @param cls the {@code Class} object to be checked
654 * @return the {@code boolean} value indicating whether objects of the
655 * type {@code cls} can be assigned to objects of this class
656 * @exception NullPointerException if the specified Class parameter is
657 * null.
658 * @since 1.1
659 */
660 @HotSpotIntrinsicCandidate
661 public native boolean isAssignableFrom(Class<?> cls);
662
663
664 /**
665 * Determines if the specified {@code Class} object represents an
666 * interface type.
667 *
668 * @return {@code true} if this object represents an interface;
669 * {@code false} otherwise.
670 */
671 @HotSpotIntrinsicCandidate
672 public native boolean isInterface();
673
674
675 /**
676 * Determines if this {@code Class} object represents an array class.
677 *
678 * @return {@code true} if this object represents an array class;
679 * {@code false} otherwise.
680 * @since 1.1
681 */
682 @HotSpotIntrinsicCandidate
683 public native boolean isArray();
684
685
686 /**
687 * Determines if the specified {@code Class} object represents a
688 * primitive type.
689 *
690 * <p> There are nine predefined {@code Class} objects to represent
691 * the eight primitive types and void. These are created by the Java
692 * Virtual Machine, and have the same names as the primitive types that
693 * they represent, namely {@code boolean}, {@code byte},
694 * {@code char}, {@code short}, {@code int},
695 * {@code long}, {@code float}, and {@code double}.
696 *
697 * <p> These objects may only be accessed via the following public static
698 * final variables, and are the only {@code Class} objects for which
699 * this method returns {@code true}.
700 *
701 * @return true if and only if this class represents a primitive type
702 *
703 * @see java.lang.Boolean#TYPE
704 * @see java.lang.Character#TYPE
705 * @see java.lang.Byte#TYPE
706 * @see java.lang.Short#TYPE
707 * @see java.lang.Integer#TYPE
708 * @see java.lang.Long#TYPE
709 * @see java.lang.Float#TYPE
710 * @see java.lang.Double#TYPE
711 * @see java.lang.Void#TYPE
712 * @since 1.1
713 */
714 @HotSpotIntrinsicCandidate
715 public native boolean isPrimitive();
716
717 /**
718 * Returns true if this {@code Class} object represents an annotation
719 * type. Note that if this method returns true, {@link #isInterface()}
720 * would also return true, as all annotation types are also interfaces.
721 *
722 * @return {@code true} if this class object represents an annotation
723 * type; {@code false} otherwise
724 * @since 1.5
725 */
726 public boolean isAnnotation() {
727 return (getModifiers() & ANNOTATION) != 0;
728 }
729
730 /**
731 * Returns {@code true} if this class is a synthetic class;
732 * returns {@code false} otherwise.
733 * @return {@code true} if and only if this class is a synthetic class as
734 * defined by the Java Language Specification.
735 * @jls 13.1 The Form of a Binary
736 * @since 1.5
737 */
738 public boolean isSynthetic() {
739 return (getModifiers() & SYNTHETIC) != 0;
740 }
741
742 /**
743 * Returns the name of the entity (class, interface, array class,
744 * primitive type, or void) represented by this {@code Class} object,
745 * as a {@code String}.
746 *
747 * <p> If this class object represents a reference type that is not an
748 * array type then the binary name of the class is returned, as specified
749 * by
750 * <cite>The Java™ Language Specification</cite>.
751 *
752 * <p> If this class object represents a primitive type or void, then the
753 * name returned is a {@code String} equal to the Java language
754 * keyword corresponding to the primitive type or void.
755 *
756 * <p> If this class object represents a class of arrays, then the internal
757 * form of the name consists of the name of the element type preceded by
758 * one or more '{@code [}' characters representing the depth of the array
759 * nesting. The encoding of element type names is as follows:
760 *
761 * <blockquote><table class="striped">
762 * <caption style="display:none">Element types and encodings</caption>
763 * <thead>
764 * <tr><th scope="col"> Element Type <th scope="col"> Encoding
765 * </thead>
766 * <tbody style="text-align:left">
767 * <tr><th scope="row"> boolean <td style="text-align:center"> Z
768 * <tr><th scope="row"> byte <td style="text-align:center"> B
769 * <tr><th scope="row"> char <td style="text-align:center"> C
770 * <tr><th scope="row"> class or interface
771 * <td style="text-align:center"> L<i>classname</i>;
772 * <tr><th scope="row"> double <td style="text-align:center"> D
773 * <tr><th scope="row"> float <td style="text-align:center"> F
774 * <tr><th scope="row"> int <td style="text-align:center"> I
775 * <tr><th scope="row"> long <td style="text-align:center"> J
776 * <tr><th scope="row"> short <td style="text-align:center"> S
777 * </tbody>
778 * </table></blockquote>
779 *
780 * <p> The class or interface name <i>classname</i> is the binary name of
781 * the class specified above.
782 *
783 * <p> Examples:
784 * <blockquote><pre>
785 * String.class.getName()
786 * returns "java.lang.String"
787 * byte.class.getName()
788 * returns "byte"
789 * (new Object[3]).getClass().getName()
790 * returns "[Ljava.lang.Object;"
791 * (new int[3][4][5][6][7][8][9]).getClass().getName()
792 * returns "[[[[[[[I"
793 * </pre></blockquote>
794 *
795 * @return the name of the class or interface
796 * represented by this object.
797 */
798 public String getName() {
799 String name = this.name;
800 return name != null ? name : initClassName();
801 }
802
803 // Cache the name to reduce the number of calls into the VM.
804 // This field would be set by VM itself during initClassName call.
805 private transient String name;
806 private native String initClassName();
807
808 /**
809 * Returns the class loader for the class. Some implementations may use
810 * null to represent the bootstrap class loader. This method will return
811 * null in such implementations if this class was loaded by the bootstrap
812 * class loader.
813 *
814 * <p>If this object
815 * represents a primitive type or void, null is returned.
816 *
817 * @return the class loader that loaded the class or interface
818 * represented by this object.
819 * @throws SecurityException
820 * if a security manager is present, and the caller's class loader
821 * is not {@code null} and is not the same as or an ancestor of the
822 * class loader for the class whose class loader is requested,
823 * and the caller does not have the
824 * {@link RuntimePermission}{@code ("getClassLoader")}
825 * @see java.lang.ClassLoader
826 * @see SecurityManager#checkPermission
827 * @see java.lang.RuntimePermission
828 */
829 @CallerSensitive
830 @ForceInline // to ensure Reflection.getCallerClass optimization
831 public ClassLoader getClassLoader() {
832 ClassLoader cl = getClassLoader0();
833 if (cl == null)
834 return null;
835 SecurityManager sm = System.getSecurityManager();
836 if (sm != null) {
837 ClassLoader.checkClassLoaderPermission(cl, Reflection.getCallerClass());
838 }
839 return cl;
840 }
841
842 // Package-private to allow ClassLoader access
843 ClassLoader getClassLoader0() { return classLoader; }
844
845 /**
846 * Returns the module that this class or interface is a member of.
847 *
848 * If this class represents an array type then this method returns the
849 * {@code Module} for the element type. If this class represents a
850 * primitive type or void, then the {@code Module} object for the
851 * {@code java.base} module is returned.
852 *
853 * If this class is in an unnamed module then the {@linkplain
854 * ClassLoader#getUnnamedModule() unnamed} {@code Module} of the class
855 * loader for this class is returned.
856 *
857 * @return the module that this class or interface is a member of
858 *
859 * @since 9
860 * @spec JPMS
861 */
862 public Module getModule() {
863 return module;
864 }
865
866 // set by VM
867 private transient Module module;
868
869 // Initialized in JVM not by private constructor
870 // This field is filtered from reflection access, i.e. getDeclaredField
871 // will throw NoSuchFieldException
872 private final ClassLoader classLoader;
873
874 /**
875 * Returns an array of {@code TypeVariable} objects that represent the
876 * type variables declared by the generic declaration represented by this
877 * {@code GenericDeclaration} object, in declaration order. Returns an
878 * array of length 0 if the underlying generic declaration declares no type
879 * variables.
880 *
881 * @return an array of {@code TypeVariable} objects that represent
882 * the type variables declared by this generic declaration
883 * @throws java.lang.reflect.GenericSignatureFormatError if the generic
884 * signature of this generic declaration does not conform to
885 * the format specified in
886 * <cite>The Java™ Virtual Machine Specification</cite>
887 * @since 1.5
888 */
889 @SuppressWarnings("unchecked")
890 public TypeVariable<Class<T>>[] getTypeParameters() {
891 ClassRepository info = getGenericInfo();
892 if (info != null)
893 return (TypeVariable<Class<T>>[])info.getTypeParameters();
894 else
895 return (TypeVariable<Class<T>>[])new TypeVariable<?>[0];
896 }
897
898
899 /**
900 * Returns the {@code Class} representing the direct superclass of the
901 * entity (class, interface, primitive type or void) represented by
902 * this {@code Class}. If this {@code Class} represents either the
903 * {@code Object} class, an interface, a primitive type, or void, then
904 * null is returned. If this object represents an array class then the
905 * {@code Class} object representing the {@code Object} class is
906 * returned.
907 *
908 * @return the direct superclass of the class represented by this object
909 */
910 @HotSpotIntrinsicCandidate
911 public native Class<? super T> getSuperclass();
912
913
914 /**
915 * Returns the {@code Type} representing the direct superclass of
916 * the entity (class, interface, primitive type or void) represented by
917 * this {@code Class}.
918 *
919 * <p>If the superclass is a parameterized type, the {@code Type}
920 * object returned must accurately reflect the actual type
921 * parameters used in the source code. The parameterized type
922 * representing the superclass is created if it had not been
923 * created before. See the declaration of {@link
924 * java.lang.reflect.ParameterizedType ParameterizedType} for the
925 * semantics of the creation process for parameterized types. If
926 * this {@code Class} represents either the {@code Object}
927 * class, an interface, a primitive type, or void, then null is
928 * returned. If this object represents an array class then the
929 * {@code Class} object representing the {@code Object} class is
930 * returned.
931 *
932 * @throws java.lang.reflect.GenericSignatureFormatError if the generic
933 * class signature does not conform to the format specified in
934 * <cite>The Java™ Virtual Machine Specification</cite>
935 * @throws TypeNotPresentException if the generic superclass
936 * refers to a non-existent type declaration
937 * @throws java.lang.reflect.MalformedParameterizedTypeException if the
938 * generic superclass refers to a parameterized type that cannot be
939 * instantiated for any reason
940 * @return the direct superclass of the class represented by this object
941 * @since 1.5
942 */
943 public Type getGenericSuperclass() {
944 ClassRepository info = getGenericInfo();
945 if (info == null) {
946 return getSuperclass();
947 }
948
949 // Historical irregularity:
950 // Generic signature marks interfaces with superclass = Object
951 // but this API returns null for interfaces
952 if (isInterface()) {
953 return null;
954 }
955
956 return info.getSuperclass();
957 }
958
959 /**
960 * Gets the package of this class.
961 *
962 * <p>If this class represents an array type, a primitive type or void,
963 * this method returns {@code null}.
964 *
965 * @return the package of this class.
966 * @revised 9
967 * @spec JPMS
968 */
969 public Package getPackage() {
970 if (isPrimitive() || isArray()) {
971 return null;
972 }
973 ClassLoader cl = getClassLoader0();
974 return cl != null ? cl.definePackage(this)
975 : BootLoader.definePackage(this);
976 }
977
978 /**
979 * Returns the fully qualified package name.
980 *
981 * <p> If this class is a top level class, then this method returns the fully
982 * qualified name of the package that the class is a member of, or the
983 * empty string if the class is in an unnamed package.
984 *
985 * <p> If this class is a member class, then this method is equivalent to
986 * invoking {@code getPackageName()} on the {@linkplain #getEnclosingClass
987 * enclosing class}.
988 *
989 * <p> If this class is a {@linkplain #isLocalClass local class} or an {@linkplain
990 * #isAnonymousClass() anonymous class}, then this method is equivalent to
991 * invoking {@code getPackageName()} on the {@linkplain #getDeclaringClass
992 * declaring class} of the {@linkplain #getEnclosingMethod enclosing method} or
993 * {@linkplain #getEnclosingConstructor enclosing constructor}.
994 *
995 * <p> If this class represents an array type then this method returns the
996 * package name of the element type. If this class represents a primitive
997 * type or void then the package name "{@code java.lang}" is returned.
998 *
999 * @return the fully qualified package name
1000 *
1001 * @since 9
1002 * @spec JPMS
1003 * @jls 6.7 Fully Qualified Names
1004 */
1005 public String getPackageName() {
1006 String pn = this.packageName;
1007 if (pn == null) {
1008 Class<?> c = this;
1009 while (c.isArray()) {
1010 c = c.getComponentType();
1011 }
1012 if (c.isPrimitive()) {
1013 pn = "java.lang";
1014 } else {
1015 String cn = c.getName();
1016 int dot = cn.lastIndexOf('.');
1017 pn = (dot != -1) ? cn.substring(0, dot).intern() : "";
1018 }
1019 this.packageName = pn;
1020 }
1021 return pn;
1022 }
1023
1024 // cached package name
1025 private transient String packageName;
1026
1027 /**
1028 * Returns the interfaces directly implemented by the class or interface
1029 * represented by this object.
1030 *
1031 * <p>If this object represents a class, the return value is an array
1032 * containing objects representing all interfaces directly implemented by
1033 * the class. The order of the interface objects in the array corresponds
1034 * to the order of the interface names in the {@code implements} clause of
1035 * the declaration of the class represented by this object. For example,
1036 * given the declaration:
1037 * <blockquote>
1038 * {@code class Shimmer implements FloorWax, DessertTopping { ... }}
1039 * </blockquote>
1040 * suppose the value of {@code s} is an instance of
1041 * {@code Shimmer}; the value of the expression:
1042 * <blockquote>
1043 * {@code s.getClass().getInterfaces()[0]}
1044 * </blockquote>
1045 * is the {@code Class} object that represents interface
1046 * {@code FloorWax}; and the value of:
1047 * <blockquote>
1048 * {@code s.getClass().getInterfaces()[1]}
1049 * </blockquote>
1050 * is the {@code Class} object that represents interface
1051 * {@code DessertTopping}.
1052 *
1053 * <p>If this object represents an interface, the array contains objects
1054 * representing all interfaces directly extended by the interface. The
1055 * order of the interface objects in the array corresponds to the order of
1056 * the interface names in the {@code extends} clause of the declaration of
1057 * the interface represented by this object.
1058 *
1059 * <p>If this object represents a class or interface that implements no
1060 * interfaces, the method returns an array of length 0.
1061 *
1062 * <p>If this object represents a primitive type or void, the method
1063 * returns an array of length 0.
1064 *
1065 * <p>If this {@code Class} object represents an array type, the
1066 * interfaces {@code Cloneable} and {@code java.io.Serializable} are
1067 * returned in that order.
1068 *
1069 * @return an array of interfaces directly implemented by this class
1070 */
1071 public Class<?>[] getInterfaces() {
1072 // defensively copy before handing over to user code
1073 return getInterfaces(true);
1074 }
1075
1076 private Class<?>[] getInterfaces(boolean cloneArray) {
1077 ReflectionData<T> rd = reflectionData();
1078 if (rd == null) {
1079 // no cloning required
1080 return getInterfaces0();
1081 } else {
1082 Class<?>[] interfaces = rd.interfaces;
1083 if (interfaces == null) {
1084 interfaces = getInterfaces0();
1085 rd.interfaces = interfaces;
1086 }
1087 // defensively copy if requested
1088 return cloneArray ? interfaces.clone() : interfaces;
1089 }
1090 }
1091
1092 private native Class<?>[] getInterfaces0();
1093
1094 /**
1095 * Returns the {@code Type}s representing the interfaces
1096 * directly implemented by the class or interface represented by
1097 * this object.
1098 *
1099 * <p>If a superinterface is a parameterized type, the
1100 * {@code Type} object returned for it must accurately reflect
1101 * the actual type parameters used in the source code. The
1102 * parameterized type representing each superinterface is created
1103 * if it had not been created before. See the declaration of
1104 * {@link java.lang.reflect.ParameterizedType ParameterizedType}
1105 * for the semantics of the creation process for parameterized
1106 * types.
1107 *
1108 * <p>If this object represents a class, the return value is an array
1109 * containing objects representing all interfaces directly implemented by
1110 * the class. The order of the interface objects in the array corresponds
1111 * to the order of the interface names in the {@code implements} clause of
1112 * the declaration of the class represented by this object.
1113 *
1114 * <p>If this object represents an interface, the array contains objects
1115 * representing all interfaces directly extended by the interface. The
1116 * order of the interface objects in the array corresponds to the order of
1117 * the interface names in the {@code extends} clause of the declaration of
1118 * the interface represented by this object.
1119 *
1120 * <p>If this object represents a class or interface that implements no
1121 * interfaces, the method returns an array of length 0.
1122 *
1123 * <p>If this object represents a primitive type or void, the method
1124 * returns an array of length 0.
1125 *
1126 * <p>If this {@code Class} object represents an array type, the
1127 * interfaces {@code Cloneable} and {@code java.io.Serializable} are
1128 * returned in that order.
1129 *
1130 * @throws java.lang.reflect.GenericSignatureFormatError
1131 * if the generic class signature does not conform to the format
1132 * specified in
1133 * <cite>The Java™ Virtual Machine Specification</cite>
1134 * @throws TypeNotPresentException if any of the generic
1135 * superinterfaces refers to a non-existent type declaration
1136 * @throws java.lang.reflect.MalformedParameterizedTypeException
1137 * if any of the generic superinterfaces refer to a parameterized
1138 * type that cannot be instantiated for any reason
1139 * @return an array of interfaces directly implemented by this class
1140 * @since 1.5
1141 */
1142 public Type[] getGenericInterfaces() {
1143 ClassRepository info = getGenericInfo();
1144 return (info == null) ? getInterfaces() : info.getSuperInterfaces();
1145 }
1146
1147
1148 /**
1149 * Returns the {@code Class} representing the component type of an
1150 * array. If this class does not represent an array class this method
1151 * returns null.
1152 *
1153 * @return the {@code Class} representing the component type of this
1154 * class if this class is an array
1155 * @see java.lang.reflect.Array
1156 * @since 1.1
1157 */
1158 public Class<?> getComponentType() {
1159 // Only return for array types. Storage may be reused for Class for instance types.
1160 if (isArray()) {
1161 return componentType;
1162 } else {
1163 return null;
1164 }
1165 }
1166
1167 private final Class<?> componentType;
1168
1169
1170 /**
1171 * Returns the Java language modifiers for this class or interface, encoded
1172 * in an integer. The modifiers consist of the Java Virtual Machine's
1173 * constants for {@code public}, {@code protected},
1174 * {@code private}, {@code final}, {@code static},
1175 * {@code abstract} and {@code interface}; they should be decoded
1176 * using the methods of class {@code Modifier}.
1177 *
1178 * <p> If the underlying class is an array class, then its
1179 * {@code public}, {@code private} and {@code protected}
1180 * modifiers are the same as those of its component type. If this
1181 * {@code Class} represents a primitive type or void, its
1182 * {@code public} modifier is always {@code true}, and its
1183 * {@code protected} and {@code private} modifiers are always
1184 * {@code false}. If this object represents an array class, a
1185 * primitive type or void, then its {@code final} modifier is always
1186 * {@code true} and its interface modifier is always
1187 * {@code false}. The values of its other modifiers are not determined
1188 * by this specification.
1189 *
1190 * <p> The modifier encodings are defined in <em>The Java Virtual Machine
1191 * Specification</em>, table 4.1.
1192 *
1193 * @return the {@code int} representing the modifiers for this class
1194 * @see java.lang.reflect.Modifier
1195 * @since 1.1
1196 */
1197 @HotSpotIntrinsicCandidate
1198 public native int getModifiers();
1199
1200
1201 /**
1202 * Gets the signers of this class.
1203 *
1204 * @return the signers of this class, or null if there are no signers. In
1205 * particular, this method returns null if this object represents
1206 * a primitive type or void.
1207 * @since 1.1
1208 */
1209 public native Object[] getSigners();
1210
1211
1212 /**
1213 * Set the signers of this class.
1214 */
1215 native void setSigners(Object[] signers);
1216
1217
1218 /**
1219 * If this {@code Class} object represents a local or anonymous
1220 * class within a method, returns a {@link
1221 * java.lang.reflect.Method Method} object representing the
1222 * immediately enclosing method of the underlying class. Returns
1223 * {@code null} otherwise.
1224 *
1225 * In particular, this method returns {@code null} if the underlying
1226 * class is a local or anonymous class immediately enclosed by a type
1227 * declaration, instance initializer or static initializer.
1228 *
1229 * @return the immediately enclosing method of the underlying class, if
1230 * that class is a local or anonymous class; otherwise {@code null}.
1231 *
1232 * @throws SecurityException
1233 * If a security manager, <i>s</i>, is present and any of the
1234 * following conditions is met:
1235 *
1236 * <ul>
1237 *
1238 * <li> the caller's class loader is not the same as the
1239 * class loader of the enclosing class and invocation of
1240 * {@link SecurityManager#checkPermission
1241 * s.checkPermission} method with
1242 * {@code RuntimePermission("accessDeclaredMembers")}
1243 * denies access to the methods within the enclosing class
1244 *
1245 * <li> the caller's class loader is not the same as or an
1246 * ancestor of the class loader for the enclosing class and
1247 * invocation of {@link SecurityManager#checkPackageAccess
1248 * s.checkPackageAccess()} denies access to the package
1249 * of the enclosing class
1250 *
1251 * </ul>
1252 * @since 1.5
1253 */
1254 @CallerSensitive
1255 public Method getEnclosingMethod() throws SecurityException {
1256 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1257
1258 if (enclosingInfo == null)
1259 return null;
1260 else {
1261 if (!enclosingInfo.isMethod())
1262 return null;
1263
1264 MethodRepository typeInfo = MethodRepository.make(enclosingInfo.getDescriptor(),
1265 getFactory());
1266 Class<?> returnType = toClass(typeInfo.getReturnType());
1267 Type [] parameterTypes = typeInfo.getParameterTypes();
1268 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length];
1269
1270 // Convert Types to Classes; returned types *should*
1271 // be class objects since the methodDescriptor's used
1272 // don't have generics information
1273 for(int i = 0; i < parameterClasses.length; i++)
1274 parameterClasses[i] = toClass(parameterTypes[i]);
1275
1276 // Perform access check
1277 final Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass();
1278 SecurityManager sm = System.getSecurityManager();
1279 if (sm != null) {
1280 enclosingCandidate.checkMemberAccess(sm, Member.DECLARED,
1281 Reflection.getCallerClass(), true);
1282 }
1283 Method[] candidates = enclosingCandidate.privateGetDeclaredMethods(false);
1284
1285 /*
1286 * Loop over all declared methods; match method name,
1287 * number of and type of parameters, *and* return
1288 * type. Matching return type is also necessary
1289 * because of covariant returns, etc.
1290 */
1291 ReflectionFactory fact = getReflectionFactory();
1292 for (Method m : candidates) {
1293 if (m.getName().equals(enclosingInfo.getName()) &&
1294 arrayContentsEq(parameterClasses,
1295 fact.getExecutableSharedParameterTypes(m))) {
1296 // finally, check return type
1297 if (m.getReturnType().equals(returnType)) {
1298 return fact.copyMethod(m);
1299 }
1300 }
1301 }
1302
1303 throw new InternalError("Enclosing method not found");
1304 }
1305 }
1306
1307 private native Object[] getEnclosingMethod0();
1308
1309 private EnclosingMethodInfo getEnclosingMethodInfo() {
1310 Object[] enclosingInfo = getEnclosingMethod0();
1311 if (enclosingInfo == null)
1312 return null;
1313 else {
1314 return new EnclosingMethodInfo(enclosingInfo);
1315 }
1316 }
1317
1318 private static final class EnclosingMethodInfo {
1319 private final Class<?> enclosingClass;
1320 private final String name;
1321 private final String descriptor;
1322
1323 static void validate(Object[] enclosingInfo) {
1324 if (enclosingInfo.length != 3)
1325 throw new InternalError("Malformed enclosing method information");
1326 try {
1327 // The array is expected to have three elements:
1328
1329 // the immediately enclosing class
1330 Class<?> enclosingClass = (Class<?>)enclosingInfo[0];
1331 assert(enclosingClass != null);
1332
1333 // the immediately enclosing method or constructor's
1334 // name (can be null).
1335 String name = (String)enclosingInfo[1];
1336
1337 // the immediately enclosing method or constructor's
1338 // descriptor (null iff name is).
1339 String descriptor = (String)enclosingInfo[2];
1340 assert((name != null && descriptor != null) || name == descriptor);
1341 } catch (ClassCastException cce) {
1342 throw new InternalError("Invalid type in enclosing method information", cce);
1343 }
1344 }
1345
1346 EnclosingMethodInfo(Object[] enclosingInfo) {
1347 validate(enclosingInfo);
1348 this.enclosingClass = (Class<?>)enclosingInfo[0];
1349 this.name = (String)enclosingInfo[1];
1350 this.descriptor = (String)enclosingInfo[2];
1351 }
1352
1353 boolean isPartial() {
1354 return enclosingClass == null || name == null || descriptor == null;
1355 }
1356
1357 boolean isConstructor() { return !isPartial() && "<init>".equals(name); }
1358
1359 boolean isMethod() { return !isPartial() && !isConstructor() && !"<clinit>".equals(name); }
1360
1361 Class<?> getEnclosingClass() { return enclosingClass; }
1362
1363 String getName() { return name; }
1364
1365 String getDescriptor() { return descriptor; }
1366
1367 }
1368
1369 private static Class<?> toClass(Type o) {
1370 if (o instanceof GenericArrayType)
1371 return Array.newInstance(toClass(((GenericArrayType)o).getGenericComponentType()),
1372 0)
1373 .getClass();
1374 return (Class<?>)o;
1375 }
1376
1377 /**
1378 * If this {@code Class} object represents a local or anonymous
1379 * class within a constructor, returns a {@link
1380 * java.lang.reflect.Constructor Constructor} object representing
1381 * the immediately enclosing constructor of the underlying
1382 * class. Returns {@code null} otherwise. In particular, this
1383 * method returns {@code null} if the underlying class is a local
1384 * or anonymous class immediately enclosed by a type declaration,
1385 * instance initializer or static initializer.
1386 *
1387 * @return the immediately enclosing constructor of the underlying class, if
1388 * that class is a local or anonymous class; otherwise {@code null}.
1389 * @throws SecurityException
1390 * If a security manager, <i>s</i>, is present and any of the
1391 * following conditions is met:
1392 *
1393 * <ul>
1394 *
1395 * <li> the caller's class loader is not the same as the
1396 * class loader of the enclosing class and invocation of
1397 * {@link SecurityManager#checkPermission
1398 * s.checkPermission} method with
1399 * {@code RuntimePermission("accessDeclaredMembers")}
1400 * denies access to the constructors within the enclosing class
1401 *
1402 * <li> the caller's class loader is not the same as or an
1403 * ancestor of the class loader for the enclosing class and
1404 * invocation of {@link SecurityManager#checkPackageAccess
1405 * s.checkPackageAccess()} denies access to the package
1406 * of the enclosing class
1407 *
1408 * </ul>
1409 * @since 1.5
1410 */
1411 @CallerSensitive
1412 public Constructor<?> getEnclosingConstructor() throws SecurityException {
1413 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1414
1415 if (enclosingInfo == null)
1416 return null;
1417 else {
1418 if (!enclosingInfo.isConstructor())
1419 return null;
1420
1421 ConstructorRepository typeInfo = ConstructorRepository.make(enclosingInfo.getDescriptor(),
1422 getFactory());
1423 Type [] parameterTypes = typeInfo.getParameterTypes();
1424 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length];
1425
1426 // Convert Types to Classes; returned types *should*
1427 // be class objects since the methodDescriptor's used
1428 // don't have generics information
1429 for(int i = 0; i < parameterClasses.length; i++)
1430 parameterClasses[i] = toClass(parameterTypes[i]);
1431
1432 // Perform access check
1433 final Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass();
1434 SecurityManager sm = System.getSecurityManager();
1435 if (sm != null) {
1436 enclosingCandidate.checkMemberAccess(sm, Member.DECLARED,
1437 Reflection.getCallerClass(), true);
1438 }
1439
1440 Constructor<?>[] candidates = enclosingCandidate
1441 .privateGetDeclaredConstructors(false);
1442 /*
1443 * Loop over all declared constructors; match number
1444 * of and type of parameters.
1445 */
1446 ReflectionFactory fact = getReflectionFactory();
1447 for (Constructor<?> c : candidates) {
1448 if (arrayContentsEq(parameterClasses,
1449 fact.getExecutableSharedParameterTypes(c))) {
1450 return fact.copyConstructor(c);
1451 }
1452 }
1453
1454 throw new InternalError("Enclosing constructor not found");
1455 }
1456 }
1457
1458
1459 /**
1460 * If the class or interface represented by this {@code Class} object
1461 * is a member of another class, returns the {@code Class} object
1462 * representing the class in which it was declared. This method returns
1463 * null if this class or interface is not a member of any other class. If
1464 * this {@code Class} object represents an array class, a primitive
1465 * type, or void,then this method returns null.
1466 *
1467 * @return the declaring class for this class
1468 * @throws SecurityException
1469 * If a security manager, <i>s</i>, is present and the caller's
1470 * class loader is not the same as or an ancestor of the class
1471 * loader for the declaring class and invocation of {@link
1472 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
1473 * denies access to the package of the declaring class
1474 * @since 1.1
1475 */
1476 @CallerSensitive
1477 public Class<?> getDeclaringClass() throws SecurityException {
1478 final Class<?> candidate = getDeclaringClass0();
1479
1480 if (candidate != null) {
1481 SecurityManager sm = System.getSecurityManager();
1482 if (sm != null) {
1483 candidate.checkPackageAccess(sm,
1484 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
1485 }
1486 }
1487 return candidate;
1488 }
1489
1490 private native Class<?> getDeclaringClass0();
1491
1492
1493 /**
1494 * Returns the immediately enclosing class of the underlying
1495 * class. If the underlying class is a top level class this
1496 * method returns {@code null}.
1497 * @return the immediately enclosing class of the underlying class
1498 * @exception SecurityException
1499 * If a security manager, <i>s</i>, is present and the caller's
1500 * class loader is not the same as or an ancestor of the class
1501 * loader for the enclosing class and invocation of {@link
1502 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
1503 * denies access to the package of the enclosing class
1504 * @since 1.5
1505 */
1506 @CallerSensitive
1507 public Class<?> getEnclosingClass() throws SecurityException {
1508 // There are five kinds of classes (or interfaces):
1509 // a) Top level classes
1510 // b) Nested classes (static member classes)
1511 // c) Inner classes (non-static member classes)
1512 // d) Local classes (named classes declared within a method)
1513 // e) Anonymous classes
1514
1515
1516 // JVM Spec 4.7.7: A class must have an EnclosingMethod
1517 // attribute if and only if it is a local class or an
1518 // anonymous class.
1519 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1520 Class<?> enclosingCandidate;
1521
1522 if (enclosingInfo == null) {
1523 // This is a top level or a nested class or an inner class (a, b, or c)
1524 enclosingCandidate = getDeclaringClass0();
1525 } else {
1526 Class<?> enclosingClass = enclosingInfo.getEnclosingClass();
1527 // This is a local class or an anonymous class (d or e)
1528 if (enclosingClass == this || enclosingClass == null)
1529 throw new InternalError("Malformed enclosing method information");
1530 else
1531 enclosingCandidate = enclosingClass;
1532 }
1533
1534 if (enclosingCandidate != null) {
1535 SecurityManager sm = System.getSecurityManager();
1536 if (sm != null) {
1537 enclosingCandidate.checkPackageAccess(sm,
1538 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
1539 }
1540 }
1541 return enclosingCandidate;
1542 }
1543
1544 /**
1545 * Returns the simple name of the underlying class as given in the
1546 * source code. Returns an empty string if the underlying class is
1547 * anonymous.
1548 *
1549 * <p>The simple name of an array is the simple name of the
1550 * component type with "[]" appended. In particular the simple
1551 * name of an array whose component type is anonymous is "[]".
1552 *
1553 * @return the simple name of the underlying class
1554 * @since 1.5
1555 */
1556 public String getSimpleName() {
1557 ReflectionData<T> rd = reflectionData();
1558 String simpleName = rd.simpleName;
1559 if (simpleName == null) {
1560 rd.simpleName = simpleName = getSimpleName0();
1561 }
1562 return simpleName;
1563 }
1564
1565 private String getSimpleName0() {
1566 if (isArray()) {
1567 return getComponentType().getSimpleName() + "[]";
1568 }
1569 String simpleName = getSimpleBinaryName();
1570 if (simpleName == null) { // top level class
1571 simpleName = getName();
1572 simpleName = simpleName.substring(simpleName.lastIndexOf('.') + 1); // strip the package name
1573 }
1574 return simpleName;
1575 }
1576
1577 /**
1578 * Return an informative string for the name of this type.
1579 *
1580 * @return an informative string for the name of this type
1581 * @since 1.8
1582 */
1583 public String getTypeName() {
1584 if (isArray()) {
1585 try {
1586 Class<?> cl = this;
1587 int dimensions = 0;
1588 do {
1589 dimensions++;
1590 cl = cl.getComponentType();
1591 } while (cl.isArray());
1592 StringBuilder sb = new StringBuilder();
1593 sb.append(cl.getName());
1594 for (int i = 0; i < dimensions; i++) {
1595 sb.append("[]");
1596 }
1597 return sb.toString();
1598 } catch (Throwable e) { /*FALLTHRU*/ }
1599 }
1600 return getName();
1601 }
1602
1603 /**
1604 * Returns the canonical name of the underlying class as
1605 * defined by the Java Language Specification. Returns null if
1606 * the underlying class does not have a canonical name (i.e., if
1607 * it is a local or anonymous class or an array whose component
1608 * type does not have a canonical name).
1609 * @return the canonical name of the underlying class if it exists, and
1610 * {@code null} otherwise.
1611 * @since 1.5
1612 */
1613 public String getCanonicalName() {
1614 ReflectionData<T> rd = reflectionData();
1615 String canonicalName = rd.canonicalName;
1616 if (canonicalName == null) {
1617 rd.canonicalName = canonicalName = getCanonicalName0();
1618 }
1619 return canonicalName == ReflectionData.NULL_SENTINEL? null : canonicalName;
1620 }
1621
1622 private String getCanonicalName0() {
1623 if (isArray()) {
1624 String canonicalName = getComponentType().getCanonicalName();
1625 if (canonicalName != null)
1626 return canonicalName + "[]";
1627 else
1628 return ReflectionData.NULL_SENTINEL;
1629 }
1630 if (isLocalOrAnonymousClass())
1631 return ReflectionData.NULL_SENTINEL;
1632 Class<?> enclosingClass = getEnclosingClass();
1633 if (enclosingClass == null) { // top level class
1634 return getName();
1635 } else {
1636 String enclosingName = enclosingClass.getCanonicalName();
1637 if (enclosingName == null)
1638 return ReflectionData.NULL_SENTINEL;
1639 return enclosingName + "." + getSimpleName();
1640 }
1641 }
1642
1643 /**
1644 * Returns {@code true} if and only if the underlying class
1645 * is an anonymous class.
1646 *
1647 * @return {@code true} if and only if this class is an anonymous class.
1648 * @since 1.5
1649 */
1650 public boolean isAnonymousClass() {
1651 return !isArray() && isLocalOrAnonymousClass() &&
1652 getSimpleBinaryName0() == null;
1653 }
1654
1655 /**
1656 * Returns {@code true} if and only if the underlying class
1657 * is a local class.
1658 *
1659 * @return {@code true} if and only if this class is a local class.
1660 * @since 1.5
1661 */
1662 public boolean isLocalClass() {
1663 return isLocalOrAnonymousClass() &&
1664 (isArray() || getSimpleBinaryName0() != null);
1665 }
1666
1667 /**
1668 * Returns {@code true} if and only if the underlying class
1669 * is a member class.
1670 *
1671 * @return {@code true} if and only if this class is a member class.
1672 * @since 1.5
1673 */
1674 public boolean isMemberClass() {
1675 return !isLocalOrAnonymousClass() && getDeclaringClass0() != null;
1676 }
1677
1678 /**
1679 * Returns the "simple binary name" of the underlying class, i.e.,
1680 * the binary name without the leading enclosing class name.
1681 * Returns {@code null} if the underlying class is a top level
1682 * class.
1683 */
1684 private String getSimpleBinaryName() {
1685 if (isTopLevelClass())
1686 return null;
1687 String name = getSimpleBinaryName0();
1688 if (name == null) // anonymous class
1689 return "";
1690 return name;
1691 }
1692
1693 private native String getSimpleBinaryName0();
1694
1695 /**
1696 * Returns {@code true} if this is a top level class. Returns {@code false}
1697 * otherwise.
1698 */
1699 private boolean isTopLevelClass() {
1700 return !isLocalOrAnonymousClass() && getDeclaringClass0() == null;
1701 }
1702
1703 /**
1704 * Returns {@code true} if this is a local class or an anonymous
1705 * class. Returns {@code false} otherwise.
1706 */
1707 private boolean isLocalOrAnonymousClass() {
1708 // JVM Spec 4.7.7: A class must have an EnclosingMethod
1709 // attribute if and only if it is a local class or an
1710 // anonymous class.
1711 return hasEnclosingMethodInfo();
1712 }
1713
1714 private boolean hasEnclosingMethodInfo() {
1715 Object[] enclosingInfo = getEnclosingMethod0();
1716 if (enclosingInfo != null) {
1717 EnclosingMethodInfo.validate(enclosingInfo);
1718 return true;
1719 }
1720 return false;
1721 }
1722
1723 /**
1724 * Returns an array containing {@code Class} objects representing all
1725 * the public classes and interfaces that are members of the class
1726 * represented by this {@code Class} object. This includes public
1727 * class and interface members inherited from superclasses and public class
1728 * and interface members declared by the class. This method returns an
1729 * array of length 0 if this {@code Class} object has no public member
1730 * classes or interfaces. This method also returns an array of length 0 if
1731 * this {@code Class} object represents a primitive type, an array
1732 * class, or void.
1733 *
1734 * @return the array of {@code Class} objects representing the public
1735 * members of this class
1736 * @throws SecurityException
1737 * If a security manager, <i>s</i>, is present and
1738 * the caller's class loader is not the same as or an
1739 * ancestor of the class loader for the current class and
1740 * invocation of {@link SecurityManager#checkPackageAccess
1741 * s.checkPackageAccess()} denies access to the package
1742 * of this class.
1743 *
1744 * @since 1.1
1745 */
1746 @CallerSensitive
1747 public Class<?>[] getClasses() {
1748 SecurityManager sm = System.getSecurityManager();
1749 if (sm != null) {
1750 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), false);
1751 }
1752
1753 // Privileged so this implementation can look at DECLARED classes,
1754 // something the caller might not have privilege to do. The code here
1755 // is allowed to look at DECLARED classes because (1) it does not hand
1756 // out anything other than public members and (2) public member access
1757 // has already been ok'd by the SecurityManager.
1758
1759 return java.security.AccessController.doPrivileged(
1760 new java.security.PrivilegedAction<>() {
1761 public Class<?>[] run() {
1762 List<Class<?>> list = new ArrayList<>();
1763 Class<?> currentClass = Class.this;
1764 while (currentClass != null) {
1765 for (Class<?> m : currentClass.getDeclaredClasses()) {
1766 if (Modifier.isPublic(m.getModifiers())) {
1767 list.add(m);
1768 }
1769 }
1770 currentClass = currentClass.getSuperclass();
1771 }
1772 return list.toArray(new Class<?>[0]);
1773 }
1774 });
1775 }
1776
1777
1778 /**
1779 * Returns an array containing {@code Field} objects reflecting all
1780 * the accessible public fields of the class or interface represented by
1781 * this {@code Class} object.
1782 *
1783 * <p> If this {@code Class} object represents a class or interface with
1784 * no accessible public fields, then this method returns an array of length
1785 * 0.
1786 *
1787 * <p> If this {@code Class} object represents a class, then this method
1788 * returns the public fields of the class and of all its superclasses and
1789 * superinterfaces.
1790 *
1791 * <p> If this {@code Class} object represents an interface, then this
1792 * method returns the fields of the interface and of all its
1793 * superinterfaces.
1794 *
1795 * <p> If this {@code Class} object represents an array type, a primitive
1796 * type, or void, then this method returns an array of length 0.
1797 *
1798 * <p> The elements in the returned array are not sorted and are not in any
1799 * particular order.
1800 *
1801 * @return the array of {@code Field} objects representing the
1802 * public fields
1803 * @throws SecurityException
1804 * If a security manager, <i>s</i>, is present and
1805 * the caller's class loader is not the same as or an
1806 * ancestor of the class loader for the current class and
1807 * invocation of {@link SecurityManager#checkPackageAccess
1808 * s.checkPackageAccess()} denies access to the package
1809 * of this class.
1810 *
1811 * @since 1.1
1812 * @jls 8.2 Class Members
1813 * @jls 8.3 Field Declarations
1814 */
1815 @CallerSensitive
1816 public Field[] getFields() throws SecurityException {
1817 SecurityManager sm = System.getSecurityManager();
1818 if (sm != null) {
1819 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
1820 }
1821 return copyFields(privateGetPublicFields());
1822 }
1823
1824
1825 /**
1826 * Returns an array containing {@code Method} objects reflecting all the
1827 * public methods of the class or interface represented by this {@code
1828 * Class} object, including those declared by the class or interface and
1829 * those inherited from superclasses and superinterfaces.
1830 *
1831 * <p> If this {@code Class} object represents an array type, then the
1832 * returned array has a {@code Method} object for each of the public
1833 * methods inherited by the array type from {@code Object}. It does not
1834 * contain a {@code Method} object for {@code clone()}.
1835 *
1836 * <p> If this {@code Class} object represents an interface then the
1837 * returned array does not contain any implicitly declared methods from
1838 * {@code Object}. Therefore, if no methods are explicitly declared in
1839 * this interface or any of its superinterfaces then the returned array
1840 * has length 0. (Note that a {@code Class} object which represents a class
1841 * always has public methods, inherited from {@code Object}.)
1842 *
1843 * <p> The returned array never contains methods with names "{@code <init>}"
1844 * or "{@code <clinit>}".
1845 *
1846 * <p> The elements in the returned array are not sorted and are not in any
1847 * particular order.
1848 *
1849 * <p> Generally, the result is computed as with the following 4 step algorithm.
1850 * Let C be the class or interface represented by this {@code Class} object:
1851 * <ol>
1852 * <li> A union of methods is composed of:
1853 * <ol type="a">
1854 * <li> C's declared public instance and static methods as returned by
1855 * {@link #getDeclaredMethods()} and filtered to include only public
1856 * methods.</li>
1857 * <li> If C is a class other than {@code Object}, then include the result
1858 * of invoking this algorithm recursively on the superclass of C.</li>
1859 * <li> Include the results of invoking this algorithm recursively on all
1860 * direct superinterfaces of C, but include only instance methods.</li>
1861 * </ol></li>
1862 * <li> Union from step 1 is partitioned into subsets of methods with same
1863 * signature (name, parameter types) and return type.</li>
1864 * <li> Within each such subset only the most specific methods are selected.
1865 * Let method M be a method from a set of methods with same signature
1866 * and return type. M is most specific if there is no such method
1867 * N != M from the same set, such that N is more specific than M.
1868 * N is more specific than M if:
1869 * <ol type="a">
1870 * <li> N is declared by a class and M is declared by an interface; or</li>
1871 * <li> N and M are both declared by classes or both by interfaces and
1872 * N's declaring type is the same as or a subtype of M's declaring type
1873 * (clearly, if M's and N's declaring types are the same type, then
1874 * M and N are the same method).</li>
1875 * </ol></li>
1876 * <li> The result of this algorithm is the union of all selected methods from
1877 * step 3.</li>
1878 * </ol>
1879 *
1880 * @apiNote There may be more than one method with a particular name
1881 * and parameter types in a class because while the Java language forbids a
1882 * class to declare multiple methods with the same signature but different
1883 * return types, the Java virtual machine does not. This
1884 * increased flexibility in the virtual machine can be used to
1885 * implement various language features. For example, covariant
1886 * returns can be implemented with {@linkplain
1887 * java.lang.reflect.Method#isBridge bridge methods}; the bridge
1888 * method and the overriding method would have the same
1889 * signature but different return types.
1890 *
1891 * @return the array of {@code Method} objects representing the
1892 * public methods of this class
1893 * @throws SecurityException
1894 * If a security manager, <i>s</i>, is present and
1895 * the caller's class loader is not the same as or an
1896 * ancestor of the class loader for the current class and
1897 * invocation of {@link SecurityManager#checkPackageAccess
1898 * s.checkPackageAccess()} denies access to the package
1899 * of this class.
1900 *
1901 * @jls 8.2 Class Members
1902 * @jls 8.4 Method Declarations
1903 * @since 1.1
1904 */
1905 @CallerSensitive
1906 public Method[] getMethods() throws SecurityException {
1907 SecurityManager sm = System.getSecurityManager();
1908 if (sm != null) {
1909 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
1910 }
1911 return copyMethods(privateGetPublicMethods());
1912 }
1913
1914
1915 /**
1916 * Returns an array containing {@code Constructor} objects reflecting
1917 * all the public constructors of the class represented by this
1918 * {@code Class} object. An array of length 0 is returned if the
1919 * class has no public constructors, or if the class is an array class, or
1920 * if the class reflects a primitive type or void.
1921 *
1922 * Note that while this method returns an array of {@code
1923 * Constructor<T>} objects (that is an array of constructors from
1924 * this class), the return type of this method is {@code
1925 * Constructor<?>[]} and <em>not</em> {@code Constructor<T>[]} as
1926 * might be expected. This less informative return type is
1927 * necessary since after being returned from this method, the
1928 * array could be modified to hold {@code Constructor} objects for
1929 * different classes, which would violate the type guarantees of
1930 * {@code Constructor<T>[]}.
1931 *
1932 * @return the array of {@code Constructor} objects representing the
1933 * public constructors of this class
1934 * @throws SecurityException
1935 * If a security manager, <i>s</i>, is present and
1936 * 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 * @since 1.1
1943 */
1944 @CallerSensitive
1945 public Constructor<?>[] getConstructors() throws SecurityException {
1946 SecurityManager sm = System.getSecurityManager();
1947 if (sm != null) {
1948 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
1949 }
1950 return copyConstructors(privateGetDeclaredConstructors(true));
1951 }
1952
1953
1954 /**
1955 * Returns a {@code Field} object that reflects the specified public member
1956 * field of the class or interface represented by this {@code Class}
1957 * object. The {@code name} parameter is a {@code String} specifying the
1958 * simple name of the desired field.
1959 *
1960 * <p> The field to be reflected is determined by the algorithm that
1961 * follows. Let C be the class or interface represented by this object:
1962 *
1963 * <OL>
1964 * <LI> If C declares a public field with the name specified, that is the
1965 * field to be reflected.</LI>
1966 * <LI> If no field was found in step 1 above, this algorithm is applied
1967 * recursively to each direct superinterface of C. The direct
1968 * superinterfaces are searched in the order they were declared.</LI>
1969 * <LI> If no field was found in steps 1 and 2 above, and C has a
1970 * superclass S, then this algorithm is invoked recursively upon S.
1971 * If C has no superclass, then a {@code NoSuchFieldException}
1972 * is thrown.</LI>
1973 * </OL>
1974 *
1975 * <p> If this {@code Class} object represents an array type, then this
1976 * method does not find the {@code length} field of the array type.
1977 *
1978 * @param name the field name
1979 * @return the {@code Field} object of this class specified by
1980 * {@code name}
1981 * @throws NoSuchFieldException if a field with the specified name is
1982 * not found.
1983 * @throws NullPointerException if {@code name} is {@code null}
1984 * @throws SecurityException
1985 * If a security manager, <i>s</i>, is present and
1986 * 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 * @since 1.1
1993 * @jls 8.2 Class Members
1994 * @jls 8.3 Field Declarations
1995 */
1996 @CallerSensitive
1997 public Field getField(String name)
1998 throws NoSuchFieldException, SecurityException {
1999 Objects.requireNonNull(name);
2000 SecurityManager sm = System.getSecurityManager();
2001 if (sm != null) {
2002 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2003 }
2004 Field field = getField0(name);
2005 if (field == null) {
2006 throw new NoSuchFieldException(name);
2007 }
2008 return getReflectionFactory().copyField(field);
2009 }
2010
2011
2012 /**
2013 * Returns a {@code Method} object that reflects the specified public
2014 * member method of the class or interface represented by this
2015 * {@code Class} object. The {@code name} parameter is a
2016 * {@code String} specifying the simple name of the desired method. The
2017 * {@code parameterTypes} parameter is an array of {@code Class}
2018 * objects that identify the method's formal parameter types, in declared
2019 * order. If {@code parameterTypes} is {@code null}, it is
2020 * treated as if it were an empty array.
2021 *
2022 * <p> If this {@code Class} object represents an array type, then this
2023 * method finds any public method inherited by the array type from
2024 * {@code Object} except method {@code clone()}.
2025 *
2026 * <p> If this {@code Class} object represents an interface then this
2027 * method does not find any implicitly declared method from
2028 * {@code Object}. Therefore, if no methods are explicitly declared in
2029 * this interface or any of its superinterfaces, then this method does not
2030 * find any method.
2031 *
2032 * <p> This method does not find any method with name "{@code <init>}" or
2033 * "{@code <clinit>}".
2034 *
2035 * <p> Generally, the method to be reflected is determined by the 4 step
2036 * algorithm that follows.
2037 * Let C be the class or interface represented by this {@code Class} object:
2038 * <ol>
2039 * <li> A union of methods is composed of:
2040 * <ol type="a">
2041 * <li> C's declared public instance and static methods as returned by
2042 * {@link #getDeclaredMethods()} and filtered to include only public
2043 * methods that match given {@code name} and {@code parameterTypes}</li>
2044 * <li> If C is a class other than {@code Object}, then include the result
2045 * of invoking this algorithm recursively on the superclass of C.</li>
2046 * <li> Include the results of invoking this algorithm recursively on all
2047 * direct superinterfaces of C, but include only instance methods.</li>
2048 * </ol></li>
2049 * <li> This union is partitioned into subsets of methods with same
2050 * return type (the selection of methods from step 1 also guarantees that
2051 * they have the same method name and parameter types).</li>
2052 * <li> Within each such subset only the most specific methods are selected.
2053 * Let method M be a method from a set of methods with same VM
2054 * signature (return type, name, parameter types).
2055 * M is most specific if there is no such method N != M from the same
2056 * set, such that N is more specific than M. N is more specific than M
2057 * if:
2058 * <ol type="a">
2059 * <li> N is declared by a class and M is declared by an interface; or</li>
2060 * <li> N and M are both declared by classes or both by interfaces and
2061 * N's declaring type is the same as or a subtype of M's declaring type
2062 * (clearly, if M's and N's declaring types are the same type, then
2063 * M and N are the same method).</li>
2064 * </ol></li>
2065 * <li> The result of this algorithm is chosen arbitrarily from the methods
2066 * with most specific return type among all selected methods from step 3.
2067 * Let R be a return type of a method M from the set of all selected methods
2068 * from step 3. M is a method with most specific return type if there is
2069 * no such method N != M from the same set, having return type S != R,
2070 * such that S is a subtype of R as determined by
2071 * R.class.{@link #isAssignableFrom}(S.class).
2072 * </ol>
2073 *
2074 * @apiNote There may be more than one method with matching name and
2075 * parameter types in a class because while the Java language forbids a
2076 * class to declare multiple methods with the same signature but different
2077 * return types, the Java virtual machine does not. This
2078 * increased flexibility in the virtual machine can be used to
2079 * implement various language features. For example, covariant
2080 * returns can be implemented with {@linkplain
2081 * java.lang.reflect.Method#isBridge bridge methods}; the bridge
2082 * method and the overriding method would have the same
2083 * signature but different return types. This method would return the
2084 * overriding method as it would have a more specific return type.
2085 *
2086 * @param name the name of the method
2087 * @param parameterTypes the list of parameters
2088 * @return the {@code Method} object that matches the specified
2089 * {@code name} and {@code parameterTypes}
2090 * @throws NoSuchMethodException if a matching method is not found
2091 * or if the name is "<init>"or "<clinit>".
2092 * @throws NullPointerException if {@code name} is {@code null}
2093 * @throws SecurityException
2094 * If a security manager, <i>s</i>, is present and
2095 * the caller's class loader is not the same as or an
2096 * ancestor of the class loader for the current class and
2097 * invocation of {@link SecurityManager#checkPackageAccess
2098 * s.checkPackageAccess()} denies access to the package
2099 * of this class.
2100 *
2101 * @jls 8.2 Class Members
2102 * @jls 8.4 Method Declarations
2103 * @since 1.1
2104 */
2105 @CallerSensitive
2106 public Method getMethod(String name, Class<?>... parameterTypes)
2107 throws NoSuchMethodException, SecurityException {
2108 Objects.requireNonNull(name);
2109 SecurityManager sm = System.getSecurityManager();
2110 if (sm != null) {
2111 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2112 }
2113 Method method = getMethod0(name, parameterTypes);
2114 if (method == null) {
2115 throw new NoSuchMethodException(methodToString(name, parameterTypes));
2116 }
2117 return getReflectionFactory().copyMethod(method);
2118 }
2119
2120 /**
2121 * Returns a {@code Constructor} object that reflects the specified
2122 * public constructor of the class represented by this {@code Class}
2123 * object. The {@code parameterTypes} parameter is an array of
2124 * {@code Class} objects that identify the constructor's formal
2125 * parameter types, in declared order.
2126 *
2127 * If this {@code Class} object represents an inner class
2128 * declared in a non-static context, the formal parameter types
2129 * include the explicit enclosing instance as the first parameter.
2130 *
2131 * <p> The constructor to reflect is the public constructor of the class
2132 * represented by this {@code Class} object whose formal parameter
2133 * types match those specified by {@code parameterTypes}.
2134 *
2135 * @param parameterTypes the parameter array
2136 * @return the {@code Constructor} object of the public constructor that
2137 * matches the specified {@code parameterTypes}
2138 * @throws NoSuchMethodException if a matching method is not found.
2139 * @throws SecurityException
2140 * If a security manager, <i>s</i>, is present and
2141 * the caller's class loader is not the same as or an
2142 * ancestor of the class loader for the current class and
2143 * invocation of {@link SecurityManager#checkPackageAccess
2144 * s.checkPackageAccess()} denies access to the package
2145 * of this class.
2146 *
2147 * @since 1.1
2148 */
2149 @CallerSensitive
2150 public Constructor<T> getConstructor(Class<?>... parameterTypes)
2151 throws NoSuchMethodException, SecurityException
2152 {
2153 SecurityManager sm = System.getSecurityManager();
2154 if (sm != null) {
2155 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2156 }
2157 return getReflectionFactory().copyConstructor(
2158 getConstructor0(parameterTypes, Member.PUBLIC));
2159 }
2160
2161
2162 /**
2163 * Returns an array of {@code Class} objects reflecting all the
2164 * classes and interfaces declared as members of the class represented by
2165 * this {@code Class} object. This includes public, protected, default
2166 * (package) access, and private classes and interfaces declared by the
2167 * class, but excludes inherited classes and interfaces. This method
2168 * returns an array of length 0 if the class declares no classes or
2169 * interfaces as members, or if this {@code Class} object represents a
2170 * primitive type, an array class, or void.
2171 *
2172 * @return the array of {@code Class} objects representing all the
2173 * declared members of this class
2174 * @throws SecurityException
2175 * If a security manager, <i>s</i>, is present and any of the
2176 * following conditions is met:
2177 *
2178 * <ul>
2179 *
2180 * <li> the caller's class loader is not the same as the
2181 * class loader of this class and invocation of
2182 * {@link SecurityManager#checkPermission
2183 * s.checkPermission} method with
2184 * {@code RuntimePermission("accessDeclaredMembers")}
2185 * denies access to the declared classes within this class
2186 *
2187 * <li> the caller's class loader is not the same as or an
2188 * ancestor of the class loader for the current class and
2189 * invocation of {@link SecurityManager#checkPackageAccess
2190 * s.checkPackageAccess()} denies access to the package
2191 * of this class
2192 *
2193 * </ul>
2194 *
2195 * @since 1.1
2196 */
2197 @CallerSensitive
2198 public Class<?>[] getDeclaredClasses() throws SecurityException {
2199 SecurityManager sm = System.getSecurityManager();
2200 if (sm != null) {
2201 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), false);
2202 }
2203 return getDeclaredClasses0();
2204 }
2205
2206
2207 /**
2208 * Returns an array of {@code Field} objects reflecting all the fields
2209 * declared by the class or interface represented by this
2210 * {@code Class} object. This includes public, protected, default
2211 * (package) access, and private fields, but excludes inherited fields.
2212 *
2213 * <p> If this {@code Class} object represents a class or interface with no
2214 * declared fields, then this method returns an array of length 0.
2215 *
2216 * <p> If this {@code Class} object represents an array type, a primitive
2217 * type, or void, then this method returns an array of length 0.
2218 *
2219 * <p> The elements in the returned array are not sorted and are not in any
2220 * particular order.
2221 *
2222 * @return the array of {@code Field} objects representing all the
2223 * declared fields of this class
2224 * @throws SecurityException
2225 * If a security manager, <i>s</i>, is present and any of the
2226 * following conditions is met:
2227 *
2228 * <ul>
2229 *
2230 * <li> the caller's class loader is not the same as the
2231 * class loader of this class and invocation of
2232 * {@link SecurityManager#checkPermission
2233 * s.checkPermission} method with
2234 * {@code RuntimePermission("accessDeclaredMembers")}
2235 * denies access to the declared fields within this class
2236 *
2237 * <li> the caller's class loader is not the same as or an
2238 * ancestor of the class loader for the current class and
2239 * invocation of {@link SecurityManager#checkPackageAccess
2240 * s.checkPackageAccess()} denies access to the package
2241 * of this class
2242 *
2243 * </ul>
2244 *
2245 * @since 1.1
2246 * @jls 8.2 Class Members
2247 * @jls 8.3 Field Declarations
2248 */
2249 @CallerSensitive
2250 public Field[] getDeclaredFields() throws SecurityException {
2251 SecurityManager sm = System.getSecurityManager();
2252 if (sm != null) {
2253 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2254 }
2255 return copyFields(privateGetDeclaredFields(false));
2256 }
2257
2258
2259 /**
2260 * Returns an array containing {@code Method} objects reflecting all the
2261 * declared methods of the class or interface represented by this {@code
2262 * Class} object, including public, protected, default (package)
2263 * access, and private methods, but excluding inherited methods.
2264 *
2265 * <p> If this {@code Class} object represents a type that has multiple
2266 * declared methods with the same name and parameter types, but different
2267 * return types, then the returned array has a {@code Method} object for
2268 * each such method.
2269 *
2270 * <p> If this {@code Class} object represents a type that has a class
2271 * initialization method {@code <clinit>}, then the returned array does
2272 * <em>not</em> have a corresponding {@code Method} object.
2273 *
2274 * <p> If this {@code Class} object represents a class or interface with no
2275 * declared methods, then the returned array has length 0.
2276 *
2277 * <p> If this {@code Class} object represents an array type, a primitive
2278 * type, or void, then the returned array has length 0.
2279 *
2280 * <p> The elements in the returned array are not sorted and are not in any
2281 * particular order.
2282 *
2283 * @return the array of {@code Method} objects representing all the
2284 * declared methods of this class
2285 * @throws SecurityException
2286 * If a security manager, <i>s</i>, is present and any of the
2287 * following conditions is met:
2288 *
2289 * <ul>
2290 *
2291 * <li> the caller's class loader is not the same as the
2292 * class loader of this class and invocation of
2293 * {@link SecurityManager#checkPermission
2294 * s.checkPermission} method with
2295 * {@code RuntimePermission("accessDeclaredMembers")}
2296 * denies access to the declared methods within this class
2297 *
2298 * <li> the caller's class loader is not the same as or an
2299 * ancestor of the class loader for the current class and
2300 * invocation of {@link SecurityManager#checkPackageAccess
2301 * s.checkPackageAccess()} denies access to the package
2302 * of this class
2303 *
2304 * </ul>
2305 *
2306 * @jls 8.2 Class Members
2307 * @jls 8.4 Method Declarations
2308 * @since 1.1
2309 */
2310 @CallerSensitive
2311 public Method[] getDeclaredMethods() throws SecurityException {
2312 SecurityManager sm = System.getSecurityManager();
2313 if (sm != null) {
2314 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2315 }
2316 return copyMethods(privateGetDeclaredMethods(false));
2317 }
2318
2319
2320 /**
2321 * Returns an array of {@code Constructor} objects reflecting all the
2322 * constructors declared by the class represented by this
2323 * {@code Class} object. These are public, protected, default
2324 * (package) access, and private constructors. The elements in the array
2325 * returned are not sorted and are not in any particular order. If the
2326 * class has a default constructor, it is included in the returned array.
2327 * This method returns an array of length 0 if this {@code Class}
2328 * object represents an interface, a primitive type, an array class, or
2329 * void.
2330 *
2331 * <p> See <em>The Java Language Specification</em>, section 8.2.
2332 *
2333 * @return the array of {@code Constructor} objects representing all the
2334 * declared constructors of this class
2335 * @throws SecurityException
2336 * If a security manager, <i>s</i>, is present and any of the
2337 * following conditions is met:
2338 *
2339 * <ul>
2340 *
2341 * <li> the caller's class loader is not the same as the
2342 * class loader of this class and invocation of
2343 * {@link SecurityManager#checkPermission
2344 * s.checkPermission} method with
2345 * {@code RuntimePermission("accessDeclaredMembers")}
2346 * denies access to the declared constructors within this class
2347 *
2348 * <li> the caller's class loader is not the same as or an
2349 * ancestor of the class loader for the current class and
2350 * invocation of {@link SecurityManager#checkPackageAccess
2351 * s.checkPackageAccess()} denies access to the package
2352 * of this class
2353 *
2354 * </ul>
2355 *
2356 * @since 1.1
2357 */
2358 @CallerSensitive
2359 public Constructor<?>[] getDeclaredConstructors() throws SecurityException {
2360 SecurityManager sm = System.getSecurityManager();
2361 if (sm != null) {
2362 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2363 }
2364 return copyConstructors(privateGetDeclaredConstructors(false));
2365 }
2366
2367
2368 /**
2369 * Returns a {@code Field} object that reflects the specified declared
2370 * field of the class or interface represented by this {@code Class}
2371 * object. The {@code name} parameter is a {@code String} that specifies
2372 * the simple name of the desired field.
2373 *
2374 * <p> If this {@code Class} object represents an array type, then this
2375 * method does not find the {@code length} field of the array type.
2376 *
2377 * @param name the name of the field
2378 * @return the {@code Field} object for the specified field in this
2379 * class
2380 * @throws NoSuchFieldException if a field with the specified name is
2381 * not found.
2382 * @throws NullPointerException if {@code name} is {@code null}
2383 * @throws SecurityException
2384 * If a security manager, <i>s</i>, is present and any of the
2385 * following conditions is met:
2386 *
2387 * <ul>
2388 *
2389 * <li> the caller's class loader is not the same as the
2390 * class loader of this class and invocation of
2391 * {@link SecurityManager#checkPermission
2392 * s.checkPermission} method with
2393 * {@code RuntimePermission("accessDeclaredMembers")}
2394 * denies access to the declared field
2395 *
2396 * <li> the caller's class loader is not the same as or an
2397 * ancestor of the class loader for the current class and
2398 * invocation of {@link SecurityManager#checkPackageAccess
2399 * s.checkPackageAccess()} denies access to the package
2400 * of this class
2401 *
2402 * </ul>
2403 *
2404 * @since 1.1
2405 * @jls 8.2 Class Members
2406 * @jls 8.3 Field Declarations
2407 */
2408 @CallerSensitive
2409 public Field getDeclaredField(String name)
2410 throws NoSuchFieldException, SecurityException {
2411 Objects.requireNonNull(name);
2412 SecurityManager sm = System.getSecurityManager();
2413 if (sm != null) {
2414 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2415 }
2416 Field field = searchFields(privateGetDeclaredFields(false), name);
2417 if (field == null) {
2418 throw new NoSuchFieldException(name);
2419 }
2420 return getReflectionFactory().copyField(field);
2421 }
2422
2423
2424 /**
2425 * Returns a {@code Method} object that reflects the specified
2426 * declared method of the class or interface represented by this
2427 * {@code Class} object. The {@code name} parameter is a
2428 * {@code String} that specifies the simple name of the desired
2429 * method, and the {@code parameterTypes} parameter is an array of
2430 * {@code Class} objects that identify the method's formal parameter
2431 * types, in declared order. If more than one method with the same
2432 * parameter types is declared in a class, and one of these methods has a
2433 * return type that is more specific than any of the others, that method is
2434 * returned; otherwise one of the methods is chosen arbitrarily. If the
2435 * name is "<init>"or "<clinit>" a {@code NoSuchMethodException}
2436 * is raised.
2437 *
2438 * <p> If this {@code Class} object represents an array type, then this
2439 * method does not find the {@code clone()} method.
2440 *
2441 * @param name the name of the method
2442 * @param parameterTypes the parameter array
2443 * @return the {@code Method} object for the method of this class
2444 * matching the specified name and parameters
2445 * @throws NoSuchMethodException if a matching method is not found.
2446 * @throws NullPointerException if {@code name} is {@code null}
2447 * @throws SecurityException
2448 * If a security manager, <i>s</i>, is present and any of the
2449 * following conditions is met:
2450 *
2451 * <ul>
2452 *
2453 * <li> the caller's class loader is not the same as the
2454 * class loader of this class and invocation of
2455 * {@link SecurityManager#checkPermission
2456 * s.checkPermission} method with
2457 * {@code RuntimePermission("accessDeclaredMembers")}
2458 * denies access to the declared method
2459 *
2460 * <li> the caller's class loader is not the same as or an
2461 * ancestor of the class loader for the current class and
2462 * invocation of {@link SecurityManager#checkPackageAccess
2463 * s.checkPackageAccess()} denies access to the package
2464 * of this class
2465 *
2466 * </ul>
2467 *
2468 * @jls 8.2 Class Members
2469 * @jls 8.4 Method Declarations
2470 * @since 1.1
2471 */
2472 @CallerSensitive
2473 public Method getDeclaredMethod(String name, Class<?>... parameterTypes)
2474 throws NoSuchMethodException, SecurityException {
2475 Objects.requireNonNull(name);
2476 SecurityManager sm = System.getSecurityManager();
2477 if (sm != null) {
2478 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2479 }
2480 Method method = searchMethods(privateGetDeclaredMethods(false), name, parameterTypes);
2481 if (method == null) {
2482 throw new NoSuchMethodException(methodToString(name, parameterTypes));
2483 }
2484 return getReflectionFactory().copyMethod(method);
2485 }
2486
2487 /**
2488 * Returns the list of {@code Method} objects for the declared public
2489 * methods of this class or interface that have the specified method name
2490 * and parameter types.
2491 *
2492 * @param name the name of the method
2493 * @param parameterTypes the parameter array
2494 * @return the list of {@code Method} objects for the public methods of
2495 * this class matching the specified name and parameters
2496 */
2497 List<Method> getDeclaredPublicMethods(String name, Class<?>... parameterTypes) {
2498 Method[] methods = privateGetDeclaredMethods(/* publicOnly */ true);
2499 ReflectionFactory factory = getReflectionFactory();
2500 List<Method> result = new ArrayList<>();
2501 for (Method method : methods) {
2502 if (method.getName().equals(name)
2503 && Arrays.equals(
2504 factory.getExecutableSharedParameterTypes(method),
2505 parameterTypes)) {
2506 result.add(factory.copyMethod(method));
2507 }
2508 }
2509 return result;
2510 }
2511
2512 /**
2513 * Returns a {@code Constructor} object that reflects the specified
2514 * constructor of the class or interface represented by this
2515 * {@code Class} object. The {@code parameterTypes} parameter is
2516 * an array of {@code Class} objects that identify the constructor's
2517 * formal parameter types, in declared order.
2518 *
2519 * If this {@code Class} object represents an inner class
2520 * declared in a non-static context, the formal parameter types
2521 * include the explicit enclosing instance as the first parameter.
2522 *
2523 * @param parameterTypes the parameter array
2524 * @return The {@code Constructor} object for the constructor with the
2525 * specified parameter list
2526 * @throws NoSuchMethodException if a matching method is not found.
2527 * @throws SecurityException
2528 * If a security manager, <i>s</i>, is present and any of the
2529 * following conditions is met:
2530 *
2531 * <ul>
2532 *
2533 * <li> the caller's class loader is not the same as the
2534 * class loader of this class and invocation of
2535 * {@link SecurityManager#checkPermission
2536 * s.checkPermission} method with
2537 * {@code RuntimePermission("accessDeclaredMembers")}
2538 * denies access to the declared constructor
2539 *
2540 * <li> the caller's class loader is not the same as or an
2541 * ancestor of the class loader for the current class and
2542 * invocation of {@link SecurityManager#checkPackageAccess
2543 * s.checkPackageAccess()} denies access to the package
2544 * of this class
2545 *
2546 * </ul>
2547 *
2548 * @since 1.1
2549 */
2550 @CallerSensitive
2551 public Constructor<T> getDeclaredConstructor(Class<?>... parameterTypes)
2552 throws NoSuchMethodException, SecurityException
2553 {
2554 SecurityManager sm = System.getSecurityManager();
2555 if (sm != null) {
2556 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2557 }
2558
2559 return getReflectionFactory().copyConstructor(
2560 getConstructor0(parameterTypes, Member.DECLARED));
2561 }
2562
2563 /**
2564 * Finds a resource with a given name.
2565 *
2566 * <p> If this class is in a named {@link Module Module} then this method
2567 * will attempt to find the resource in the module. This is done by
2568 * delegating to the module's class loader {@link
2569 * ClassLoader#findResource(String,String) findResource(String,String)}
2570 * method, invoking it with the module name and the absolute name of the
2571 * resource. Resources in named modules are subject to the rules for
2572 * encapsulation specified in the {@code Module} {@link
2573 * Module#getResourceAsStream getResourceAsStream} method and so this
2574 * method returns {@code null} when the resource is a
2575 * non-"{@code .class}" resource in a package that is not open to the
2576 * caller's module.
2577 *
2578 * <p> Otherwise, if this class is not in a named module then the rules for
2579 * searching resources associated with a given class are implemented by the
2580 * defining {@linkplain ClassLoader class loader} of the class. This method
2581 * delegates to this object's class loader. If this object was loaded by
2582 * the bootstrap class loader, the method delegates to {@link
2583 * ClassLoader#getSystemResourceAsStream}.
2584 *
2585 * <p> Before delegation, an absolute resource name is constructed from the
2586 * given resource name using this algorithm:
2587 *
2588 * <ul>
2589 *
2590 * <li> If the {@code name} begins with a {@code '/'}
2591 * (<code>'\u002f'</code>), then the absolute name of the resource is the
2592 * portion of the {@code name} following the {@code '/'}.
2593 *
2594 * <li> Otherwise, the absolute name is of the following form:
2595 *
2596 * <blockquote>
2597 * {@code modified_package_name/name}
2598 * </blockquote>
2599 *
2600 * <p> Where the {@code modified_package_name} is the package name of this
2601 * object with {@code '/'} substituted for {@code '.'}
2602 * (<code>'\u002e'</code>).
2603 *
2604 * </ul>
2605 *
2606 * @param name name of the desired resource
2607 * @return A {@link java.io.InputStream} object; {@code null} if no
2608 * resource with this name is found, the resource is in a package
2609 * that is not {@linkplain Module#isOpen(String, Module) open} to at
2610 * least the caller module, or access to the resource is denied
2611 * by the security manager.
2612 * @throws NullPointerException If {@code name} is {@code null}
2613 *
2614 * @see Module#getResourceAsStream(String)
2615 * @since 1.1
2616 * @revised 9
2617 * @spec JPMS
2618 */
2619 @CallerSensitive
2620 public InputStream getResourceAsStream(String name) {
2621 name = resolveName(name);
2622
2623 Module thisModule = getModule();
2624 if (thisModule.isNamed()) {
2625 // check if resource can be located by caller
2626 if (Resources.canEncapsulate(name)
2627 && !isOpenToCaller(name, Reflection.getCallerClass())) {
2628 return null;
2629 }
2630
2631 // resource not encapsulated or in package open to caller
2632 String mn = thisModule.getName();
2633 ClassLoader cl = getClassLoader0();
2634 try {
2635
2636 // special-case built-in class loaders to avoid the
2637 // need for a URL connection
2638 if (cl == null) {
2639 return BootLoader.findResourceAsStream(mn, name);
2640 } else if (cl instanceof BuiltinClassLoader) {
2641 return ((BuiltinClassLoader) cl).findResourceAsStream(mn, name);
2642 } else {
2643 URL url = cl.findResource(mn, name);
2644 return (url != null) ? url.openStream() : null;
2645 }
2646
2647 } catch (IOException | SecurityException e) {
2648 return null;
2649 }
2650 }
2651
2652 // unnamed module
2653 ClassLoader cl = getClassLoader0();
2654 if (cl == null) {
2655 return ClassLoader.getSystemResourceAsStream(name);
2656 } else {
2657 return cl.getResourceAsStream(name);
2658 }
2659 }
2660
2661 /**
2662 * Finds a resource with a given name.
2663 *
2664 * <p> If this class is in a named {@link Module Module} then this method
2665 * will attempt to find the resource in the module. This is done by
2666 * delegating to the module's class loader {@link
2667 * ClassLoader#findResource(String,String) findResource(String,String)}
2668 * method, invoking it with the module name and the absolute name of the
2669 * resource. Resources in named modules are subject to the rules for
2670 * encapsulation specified in the {@code Module} {@link
2671 * Module#getResourceAsStream getResourceAsStream} method and so this
2672 * method returns {@code null} when the resource is a
2673 * non-"{@code .class}" resource in a package that is not open to the
2674 * caller's module.
2675 *
2676 * <p> Otherwise, if this class is not in a named module then the rules for
2677 * searching resources associated with a given class are implemented by the
2678 * defining {@linkplain ClassLoader class loader} of the class. This method
2679 * delegates to this object's class loader. If this object was loaded by
2680 * the bootstrap class loader, the method delegates to {@link
2681 * ClassLoader#getSystemResource}.
2682 *
2683 * <p> Before delegation, an absolute resource name is constructed from the
2684 * given resource name using this algorithm:
2685 *
2686 * <ul>
2687 *
2688 * <li> If the {@code name} begins with a {@code '/'}
2689 * (<code>'\u002f'</code>), then the absolute name of the resource is the
2690 * portion of the {@code name} following the {@code '/'}.
2691 *
2692 * <li> Otherwise, the absolute name is of the following form:
2693 *
2694 * <blockquote>
2695 * {@code modified_package_name/name}
2696 * </blockquote>
2697 *
2698 * <p> Where the {@code modified_package_name} is the package name of this
2699 * object with {@code '/'} substituted for {@code '.'}
2700 * (<code>'\u002e'</code>).
2701 *
2702 * </ul>
2703 *
2704 * @param name name of the desired resource
2705 * @return A {@link java.net.URL} object; {@code null} if no resource with
2706 * this name is found, the resource cannot be located by a URL, the
2707 * resource is in a package that is not
2708 * {@linkplain Module#isOpen(String, Module) open} to at least the caller
2709 * module, or access to the resource is denied by the security
2710 * manager.
2711 * @throws NullPointerException If {@code name} is {@code null}
2712 * @since 1.1
2713 * @revised 9
2714 * @spec JPMS
2715 */
2716 @CallerSensitive
2717 public URL getResource(String name) {
2718 name = resolveName(name);
2719
2720 Module thisModule = getModule();
2721 if (thisModule.isNamed()) {
2722 // check if resource can be located by caller
2723 if (Resources.canEncapsulate(name)
2724 && !isOpenToCaller(name, Reflection.getCallerClass())) {
2725 return null;
2726 }
2727
2728 // resource not encapsulated or in package open to caller
2729 String mn = thisModule.getName();
2730 ClassLoader cl = getClassLoader0();
2731 try {
2732 if (cl == null) {
2733 return BootLoader.findResource(mn, name);
2734 } else {
2735 return cl.findResource(mn, name);
2736 }
2737 } catch (IOException ioe) {
2738 return null;
2739 }
2740 }
2741
2742 // unnamed module
2743 ClassLoader cl = getClassLoader0();
2744 if (cl == null) {
2745 return ClassLoader.getSystemResource(name);
2746 } else {
2747 return cl.getResource(name);
2748 }
2749 }
2750
2751 /**
2752 * Returns true if a resource with the given name can be located by the
2753 * given caller. All resources in a module can be located by code in
2754 * the module. For other callers, then the package needs to be open to
2755 * the caller.
2756 */
2757 private boolean isOpenToCaller(String name, Class<?> caller) {
2758 // assert getModule().isNamed();
2759 Module thisModule = getModule();
2760 Module callerModule = (caller != null) ? caller.getModule() : null;
2761 if (callerModule != thisModule) {
2762 String pn = Resources.toPackageName(name);
2763 if (thisModule.getDescriptor().packages().contains(pn)) {
2764 if (callerModule == null && !thisModule.isOpen(pn)) {
2765 // no caller, package not open
2766 return false;
2767 }
2768 if (!thisModule.isOpen(pn, callerModule)) {
2769 // package not open to caller
2770 return false;
2771 }
2772 }
2773 }
2774 return true;
2775 }
2776
2777
2778 /** protection domain returned when the internal domain is null */
2779 private static java.security.ProtectionDomain allPermDomain;
2780
2781 /**
2782 * Returns the {@code ProtectionDomain} of this class. If there is a
2783 * security manager installed, this method first calls the security
2784 * manager's {@code checkPermission} method with a
2785 * {@code RuntimePermission("getProtectionDomain")} permission to
2786 * ensure it's ok to get the
2787 * {@code ProtectionDomain}.
2788 *
2789 * @return the ProtectionDomain of this class
2790 *
2791 * @throws SecurityException
2792 * if a security manager exists and its
2793 * {@code checkPermission} method doesn't allow
2794 * getting the ProtectionDomain.
2795 *
2796 * @see java.security.ProtectionDomain
2797 * @see SecurityManager#checkPermission
2798 * @see java.lang.RuntimePermission
2799 * @since 1.2
2800 */
2801 public java.security.ProtectionDomain getProtectionDomain() {
2802 SecurityManager sm = System.getSecurityManager();
2803 if (sm != null) {
2804 sm.checkPermission(SecurityConstants.GET_PD_PERMISSION);
2805 }
2806 java.security.ProtectionDomain pd = getProtectionDomain0();
2807 if (pd == null) {
2808 if (allPermDomain == null) {
2809 java.security.Permissions perms =
2810 new java.security.Permissions();
2811 perms.add(SecurityConstants.ALL_PERMISSION);
2812 allPermDomain =
2813 new java.security.ProtectionDomain(null, perms);
2814 }
2815 pd = allPermDomain;
2816 }
2817 return pd;
2818 }
2819
2820
2821 /**
2822 * Returns the ProtectionDomain of this class.
2823 */
2824 private native java.security.ProtectionDomain getProtectionDomain0();
2825
2826 /*
2827 * Return the Virtual Machine's Class object for the named
2828 * primitive type.
2829 */
2830 static native Class<?> getPrimitiveClass(String name);
2831
2832 /*
2833 * Check if client is allowed to access members. If access is denied,
2834 * throw a SecurityException.
2835 *
2836 * This method also enforces package access.
2837 *
2838 * <p> Default policy: allow all clients access with normal Java access
2839 * control.
2840 *
2841 * <p> NOTE: should only be called if a SecurityManager is installed
2842 */
2843 private void checkMemberAccess(SecurityManager sm, int which,
2844 Class<?> caller, boolean checkProxyInterfaces) {
2845 /* Default policy allows access to all {@link Member#PUBLIC} members,
2846 * as well as access to classes that have the same class loader as the caller.
2847 * In all other cases, it requires RuntimePermission("accessDeclaredMembers")
2848 * permission.
2849 */
2850 final ClassLoader ccl = ClassLoader.getClassLoader(caller);
2851 if (which != Member.PUBLIC) {
2852 final ClassLoader cl = getClassLoader0();
2853 if (ccl != cl) {
2854 sm.checkPermission(SecurityConstants.CHECK_MEMBER_ACCESS_PERMISSION);
2855 }
2856 }
2857 this.checkPackageAccess(sm, ccl, checkProxyInterfaces);
2858 }
2859
2860 /*
2861 * Checks if a client loaded in ClassLoader ccl is allowed to access this
2862 * class under the current package access policy. If access is denied,
2863 * throw a SecurityException.
2864 *
2865 * NOTE: this method should only be called if a SecurityManager is active
2866 */
2867 private void checkPackageAccess(SecurityManager sm, final ClassLoader ccl,
2868 boolean checkProxyInterfaces) {
2869 final ClassLoader cl = getClassLoader0();
2870
2871 if (ReflectUtil.needsPackageAccessCheck(ccl, cl)) {
2872 String pkg = this.getPackageName();
2873 if (pkg != null && !pkg.isEmpty()) {
2874 // skip the package access check on a proxy class in default proxy package
2875 if (!Proxy.isProxyClass(this) || ReflectUtil.isNonPublicProxyClass(this)) {
2876 sm.checkPackageAccess(pkg);
2877 }
2878 }
2879 }
2880 // check package access on the proxy interfaces
2881 if (checkProxyInterfaces && Proxy.isProxyClass(this)) {
2882 ReflectUtil.checkProxyPackageAccess(ccl, this.getInterfaces());
2883 }
2884 }
2885
2886 /**
2887 * Add a package name prefix if the name is not absolute Remove leading "/"
2888 * if name is absolute
2889 */
2890 private String resolveName(String name) {
2891 if (!name.startsWith("/")) {
2892 Class<?> c = this;
2893 while (c.isArray()) {
2894 c = c.getComponentType();
2895 }
2896 String baseName = c.getPackageName();
2897 if (baseName != null && !baseName.isEmpty()) {
2898 name = baseName.replace('.', '/') + "/" + name;
2899 }
2900 } else {
2901 name = name.substring(1);
2902 }
2903 return name;
2904 }
2905
2906 /**
2907 * Atomic operations support.
2908 */
2909 private static class Atomic {
2910 // initialize Unsafe machinery here, since we need to call Class.class instance method
2911 // and have to avoid calling it in the static initializer of the Class class...
2912 private static final Unsafe unsafe = Unsafe.getUnsafe();
2913 // offset of Class.reflectionData instance field
2914 private static final long reflectionDataOffset
2915 = unsafe.objectFieldOffset(Class.class, "reflectionData");
2916 // offset of Class.annotationType instance field
2917 private static final long annotationTypeOffset
2918 = unsafe.objectFieldOffset(Class.class, "annotationType");
2919 // offset of Class.annotationData instance field
2920 private static final long annotationDataOffset
2921 = unsafe.objectFieldOffset(Class.class, "annotationData");
2922
2923 static <T> boolean casReflectionData(Class<?> clazz,
2924 SoftReference<ReflectionData<T>> oldData,
2925 SoftReference<ReflectionData<T>> newData) {
2926 return unsafe.compareAndSetReference(clazz, reflectionDataOffset, oldData, newData);
2927 }
2928
2929 static <T> boolean casAnnotationType(Class<?> clazz,
2930 AnnotationType oldType,
2931 AnnotationType newType) {
2932 return unsafe.compareAndSetReference(clazz, annotationTypeOffset, oldType, newType);
2933 }
2934
2935 static <T> boolean casAnnotationData(Class<?> clazz,
2936 AnnotationData oldData,
2937 AnnotationData newData) {
2938 return unsafe.compareAndSetReference(clazz, annotationDataOffset, oldData, newData);
2939 }
2940 }
2941
2942 /**
2943 * Reflection support.
2944 */
2945
2946 // Reflection data caches various derived names and reflective members. Cached
2947 // values may be invalidated when JVM TI RedefineClasses() is called
2948 private static class ReflectionData<T> {
2949 volatile Field[] declaredFields;
2950 volatile Field[] publicFields;
2951 volatile Method[] declaredMethods;
2952 volatile Method[] publicMethods;
2953 volatile Constructor<T>[] declaredConstructors;
2954 volatile Constructor<T>[] publicConstructors;
2955 // Intermediate results for getFields and getMethods
2956 volatile Field[] declaredPublicFields;
2957 volatile Method[] declaredPublicMethods;
2958 volatile Class<?>[] interfaces;
2959
2960 // Cached names
2961 String simpleName;
2962 String canonicalName;
2963 static final String NULL_SENTINEL = new String();
2964
2965 // Value of classRedefinedCount when we created this ReflectionData instance
2966 final int redefinedCount;
2967
2968 ReflectionData(int redefinedCount) {
2969 this.redefinedCount = redefinedCount;
2970 }
2971 }
2972
2973 private transient volatile SoftReference<ReflectionData<T>> reflectionData;
2974
2975 // Incremented by the VM on each call to JVM TI RedefineClasses()
2976 // that redefines this class or a superclass.
2977 private transient volatile int classRedefinedCount;
2978
2979 // Lazily create and cache ReflectionData
2980 private ReflectionData<T> reflectionData() {
2981 SoftReference<ReflectionData<T>> reflectionData = this.reflectionData;
2982 int classRedefinedCount = this.classRedefinedCount;
2983 ReflectionData<T> rd;
2984 if (reflectionData != null &&
2985 (rd = reflectionData.get()) != null &&
2986 rd.redefinedCount == classRedefinedCount) {
2987 return rd;
2988 }
2989 // else no SoftReference or cleared SoftReference or stale ReflectionData
2990 // -> create and replace new instance
2991 return newReflectionData(reflectionData, classRedefinedCount);
2992 }
2993
2994 private ReflectionData<T> newReflectionData(SoftReference<ReflectionData<T>> oldReflectionData,
2995 int classRedefinedCount) {
2996 while (true) {
2997 ReflectionData<T> rd = new ReflectionData<>(classRedefinedCount);
2998 // try to CAS it...
2999 if (Atomic.casReflectionData(this, oldReflectionData, new SoftReference<>(rd))) {
3000 return rd;
3001 }
3002 // else retry
3003 oldReflectionData = this.reflectionData;
3004 classRedefinedCount = this.classRedefinedCount;
3005 if (oldReflectionData != null &&
3006 (rd = oldReflectionData.get()) != null &&
3007 rd.redefinedCount == classRedefinedCount) {
3008 return rd;
3009 }
3010 }
3011 }
3012
3013 // Generic signature handling
3014 private native String getGenericSignature0();
3015
3016 // Generic info repository; lazily initialized
3017 private transient volatile ClassRepository genericInfo;
3018
3019 // accessor for factory
3020 private GenericsFactory getFactory() {
3021 // create scope and factory
3022 return CoreReflectionFactory.make(this, ClassScope.make(this));
3023 }
3024
3025 // accessor for generic info repository;
3026 // generic info is lazily initialized
3027 private ClassRepository getGenericInfo() {
3028 ClassRepository genericInfo = this.genericInfo;
3029 if (genericInfo == null) {
3030 String signature = getGenericSignature0();
3031 if (signature == null) {
3032 genericInfo = ClassRepository.NONE;
3033 } else {
3034 genericInfo = ClassRepository.make(signature, getFactory());
3035 }
3036 this.genericInfo = genericInfo;
3037 }
3038 return (genericInfo != ClassRepository.NONE) ? genericInfo : null;
3039 }
3040
3041 // Annotations handling
3042 native byte[] getRawAnnotations();
3043 // Since 1.8
3044 native byte[] getRawTypeAnnotations();
3045 static byte[] getExecutableTypeAnnotationBytes(Executable ex) {
3046 return getReflectionFactory().getExecutableTypeAnnotationBytes(ex);
3047 }
3048
3049 native ConstantPool getConstantPool();
3050
3051 //
3052 //
3053 // java.lang.reflect.Field handling
3054 //
3055 //
3056
3057 // Returns an array of "root" fields. These Field objects must NOT
3058 // be propagated to the outside world, but must instead be copied
3059 // via ReflectionFactory.copyField.
3060 private Field[] privateGetDeclaredFields(boolean publicOnly) {
3061 Field[] res;
3062 ReflectionData<T> rd = reflectionData();
3063 if (rd != null) {
3064 res = publicOnly ? rd.declaredPublicFields : rd.declaredFields;
3065 if (res != null) return res;
3066 }
3067 // No cached value available; request value from VM
3068 res = Reflection.filterFields(this, getDeclaredFields0(publicOnly));
3069 if (rd != null) {
3070 if (publicOnly) {
3071 rd.declaredPublicFields = res;
3072 } else {
3073 rd.declaredFields = res;
3074 }
3075 }
3076 return res;
3077 }
3078
3079 // Returns an array of "root" fields. These Field objects must NOT
3080 // be propagated to the outside world, but must instead be copied
3081 // via ReflectionFactory.copyField.
3082 private Field[] privateGetPublicFields() {
3083 Field[] res;
3084 ReflectionData<T> rd = reflectionData();
3085 if (rd != null) {
3086 res = rd.publicFields;
3087 if (res != null) return res;
3088 }
3089
3090 // Use a linked hash set to ensure order is preserved and
3091 // fields from common super interfaces are not duplicated
3092 LinkedHashSet<Field> fields = new LinkedHashSet<>();
3093
3094 // Local fields
3095 addAll(fields, privateGetDeclaredFields(true));
3096
3097 // Direct superinterfaces, recursively
3098 for (Class<?> si : getInterfaces()) {
3099 addAll(fields, si.privateGetPublicFields());
3100 }
3101
3102 // Direct superclass, recursively
3103 Class<?> sc = getSuperclass();
3104 if (sc != null) {
3105 addAll(fields, sc.privateGetPublicFields());
3106 }
3107
3108 res = fields.toArray(new Field[0]);
3109 if (rd != null) {
3110 rd.publicFields = res;
3111 }
3112 return res;
3113 }
3114
3115 private static void addAll(Collection<Field> c, Field[] o) {
3116 for (Field f : o) {
3117 c.add(f);
3118 }
3119 }
3120
3121
3122 //
3123 //
3124 // java.lang.reflect.Constructor handling
3125 //
3126 //
3127
3128 // Returns an array of "root" constructors. These Constructor
3129 // objects must NOT be propagated to the outside world, but must
3130 // instead be copied via ReflectionFactory.copyConstructor.
3131 private Constructor<T>[] privateGetDeclaredConstructors(boolean publicOnly) {
3132 Constructor<T>[] res;
3133 ReflectionData<T> rd = reflectionData();
3134 if (rd != null) {
3135 res = publicOnly ? rd.publicConstructors : rd.declaredConstructors;
3136 if (res != null) return res;
3137 }
3138 // No cached value available; request value from VM
3139 if (isInterface()) {
3140 @SuppressWarnings("unchecked")
3141 Constructor<T>[] temporaryRes = (Constructor<T>[]) new Constructor<?>[0];
3142 res = temporaryRes;
3143 } else {
3144 res = getDeclaredConstructors0(publicOnly);
3145 }
3146 if (rd != null) {
3147 if (publicOnly) {
3148 rd.publicConstructors = res;
3149 } else {
3150 rd.declaredConstructors = res;
3151 }
3152 }
3153 return res;
3154 }
3155
3156 //
3157 //
3158 // java.lang.reflect.Method handling
3159 //
3160 //
3161
3162 // Returns an array of "root" methods. These Method objects must NOT
3163 // be propagated to the outside world, but must instead be copied
3164 // via ReflectionFactory.copyMethod.
3165 private Method[] privateGetDeclaredMethods(boolean publicOnly) {
3166 Method[] res;
3167 ReflectionData<T> rd = reflectionData();
3168 if (rd != null) {
3169 res = publicOnly ? rd.declaredPublicMethods : rd.declaredMethods;
3170 if (res != null) return res;
3171 }
3172 // No cached value available; request value from VM
3173 res = Reflection.filterMethods(this, getDeclaredMethods0(publicOnly));
3174 if (rd != null) {
3175 if (publicOnly) {
3176 rd.declaredPublicMethods = res;
3177 } else {
3178 rd.declaredMethods = res;
3179 }
3180 }
3181 return res;
3182 }
3183
3184 // Returns an array of "root" methods. These Method objects must NOT
3185 // be propagated to the outside world, but must instead be copied
3186 // via ReflectionFactory.copyMethod.
3187 private Method[] privateGetPublicMethods() {
3188 Method[] res;
3189 ReflectionData<T> rd = reflectionData();
3190 if (rd != null) {
3191 res = rd.publicMethods;
3192 if (res != null) return res;
3193 }
3194
3195 // No cached value available; compute value recursively.
3196 // Start by fetching public declared methods...
3197 PublicMethods pms = new PublicMethods();
3198 for (Method m : privateGetDeclaredMethods(/* publicOnly */ true)) {
3199 pms.merge(m);
3200 }
3201 // ...then recur over superclass methods...
3202 Class<?> sc = getSuperclass();
3203 if (sc != null) {
3204 for (Method m : sc.privateGetPublicMethods()) {
3205 pms.merge(m);
3206 }
3207 }
3208 // ...and finally over direct superinterfaces.
3209 for (Class<?> intf : getInterfaces(/* cloneArray */ false)) {
3210 for (Method m : intf.privateGetPublicMethods()) {
3211 // static interface methods are not inherited
3212 if (!Modifier.isStatic(m.getModifiers())) {
3213 pms.merge(m);
3214 }
3215 }
3216 }
3217
3218 res = pms.toArray();
3219 if (rd != null) {
3220 rd.publicMethods = res;
3221 }
3222 return res;
3223 }
3224
3225
3226 //
3227 // Helpers for fetchers of one field, method, or constructor
3228 //
3229
3230 // This method does not copy the returned Field object!
3231 private static Field searchFields(Field[] fields, String name) {
3232 for (Field field : fields) {
3233 if (field.getName().equals(name)) {
3234 return field;
3235 }
3236 }
3237 return null;
3238 }
3239
3240 // Returns a "root" Field object. This Field object must NOT
3241 // be propagated to the outside world, but must instead be copied
3242 // via ReflectionFactory.copyField.
3243 private Field getField0(String name) {
3244 // Note: the intent is that the search algorithm this routine
3245 // uses be equivalent to the ordering imposed by
3246 // privateGetPublicFields(). It fetches only the declared
3247 // public fields for each class, however, to reduce the number
3248 // of Field objects which have to be created for the common
3249 // case where the field being requested is declared in the
3250 // class which is being queried.
3251 Field res;
3252 // Search declared public fields
3253 if ((res = searchFields(privateGetDeclaredFields(true), name)) != null) {
3254 return res;
3255 }
3256 // Direct superinterfaces, recursively
3257 Class<?>[] interfaces = getInterfaces(/* cloneArray */ false);
3258 for (Class<?> c : interfaces) {
3259 if ((res = c.getField0(name)) != null) {
3260 return res;
3261 }
3262 }
3263 // Direct superclass, recursively
3264 if (!isInterface()) {
3265 Class<?> c = getSuperclass();
3266 if (c != null) {
3267 if ((res = c.getField0(name)) != null) {
3268 return res;
3269 }
3270 }
3271 }
3272 return null;
3273 }
3274
3275 // This method does not copy the returned Method object!
3276 private static Method searchMethods(Method[] methods,
3277 String name,
3278 Class<?>[] parameterTypes)
3279 {
3280 ReflectionFactory fact = getReflectionFactory();
3281 Method res = null;
3282 for (Method m : methods) {
3283 if (m.getName().equals(name)
3284 && arrayContentsEq(parameterTypes,
3285 fact.getExecutableSharedParameterTypes(m))
3286 && (res == null
3287 || (res.getReturnType() != m.getReturnType()
3288 && res.getReturnType().isAssignableFrom(m.getReturnType()))))
3289 res = m;
3290 }
3291 return res;
3292 }
3293
3294 private static final Class<?>[] EMPTY_CLASS_ARRAY = new Class<?>[0];
3295
3296 // Returns a "root" Method object. This Method object must NOT
3297 // be propagated to the outside world, but must instead be copied
3298 // via ReflectionFactory.copyMethod.
3299 private Method getMethod0(String name, Class<?>[] parameterTypes) {
3300 PublicMethods.MethodList res = getMethodsRecursive(
3301 name,
3302 parameterTypes == null ? EMPTY_CLASS_ARRAY : parameterTypes,
3303 /* includeStatic */ true);
3304 return res == null ? null : res.getMostSpecific();
3305 }
3306
3307 // Returns a list of "root" Method objects. These Method objects must NOT
3308 // be propagated to the outside world, but must instead be copied
3309 // via ReflectionFactory.copyMethod.
3310 private PublicMethods.MethodList getMethodsRecursive(String name,
3311 Class<?>[] parameterTypes,
3312 boolean includeStatic) {
3313 // 1st check declared public methods
3314 Method[] methods = privateGetDeclaredMethods(/* publicOnly */ true);
3315 PublicMethods.MethodList res = PublicMethods.MethodList
3316 .filter(methods, name, parameterTypes, includeStatic);
3317 // if there is at least one match among declared methods, we need not
3318 // search any further as such match surely overrides matching methods
3319 // declared in superclass(es) or interface(s).
3320 if (res != null) {
3321 return res;
3322 }
3323
3324 // if there was no match among declared methods,
3325 // we must consult the superclass (if any) recursively...
3326 Class<?> sc = getSuperclass();
3327 if (sc != null) {
3328 res = sc.getMethodsRecursive(name, parameterTypes, includeStatic);
3329 }
3330
3331 // ...and coalesce the superclass methods with methods obtained
3332 // from directly implemented interfaces excluding static methods...
3333 for (Class<?> intf : getInterfaces(/* cloneArray */ false)) {
3334 res = PublicMethods.MethodList.merge(
3335 res, intf.getMethodsRecursive(name, parameterTypes,
3336 /* includeStatic */ false));
3337 }
3338
3339 return res;
3340 }
3341
3342 // Returns a "root" Constructor object. This Constructor object must NOT
3343 // be propagated to the outside world, but must instead be copied
3344 // via ReflectionFactory.copyConstructor.
3345 private Constructor<T> getConstructor0(Class<?>[] parameterTypes,
3346 int which) throws NoSuchMethodException
3347 {
3348 ReflectionFactory fact = getReflectionFactory();
3349 Constructor<T>[] constructors = privateGetDeclaredConstructors((which == Member.PUBLIC));
3350 for (Constructor<T> constructor : constructors) {
3351 if (arrayContentsEq(parameterTypes,
3352 fact.getExecutableSharedParameterTypes(constructor))) {
3353 return constructor;
3354 }
3355 }
3356 throw new NoSuchMethodException(methodToString("<init>", parameterTypes));
3357 }
3358
3359 //
3360 // Other helpers and base implementation
3361 //
3362
3363 private static boolean arrayContentsEq(Object[] a1, Object[] a2) {
3364 if (a1 == null) {
3365 return a2 == null || a2.length == 0;
3366 }
3367
3368 if (a2 == null) {
3369 return a1.length == 0;
3370 }
3371
3372 if (a1.length != a2.length) {
3373 return false;
3374 }
3375
3376 for (int i = 0; i < a1.length; i++) {
3377 if (a1[i] != a2[i]) {
3378 return false;
3379 }
3380 }
3381
3382 return true;
3383 }
3384
3385 private static Field[] copyFields(Field[] arg) {
3386 Field[] out = new Field[arg.length];
3387 ReflectionFactory fact = getReflectionFactory();
3388 for (int i = 0; i < arg.length; i++) {
3389 out[i] = fact.copyField(arg[i]);
3390 }
3391 return out;
3392 }
3393
3394 private static Method[] copyMethods(Method[] arg) {
3395 Method[] out = new Method[arg.length];
3396 ReflectionFactory fact = getReflectionFactory();
3397 for (int i = 0; i < arg.length; i++) {
3398 out[i] = fact.copyMethod(arg[i]);
3399 }
3400 return out;
3401 }
3402
3403 private static <U> Constructor<U>[] copyConstructors(Constructor<U>[] arg) {
3404 Constructor<U>[] out = arg.clone();
3405 ReflectionFactory fact = getReflectionFactory();
3406 for (int i = 0; i < out.length; i++) {
3407 out[i] = fact.copyConstructor(out[i]);
3408 }
3409 return out;
3410 }
3411
3412 private native Field[] getDeclaredFields0(boolean publicOnly);
3413 private native Method[] getDeclaredMethods0(boolean publicOnly);
3414 private native Constructor<T>[] getDeclaredConstructors0(boolean publicOnly);
3415 private native Class<?>[] getDeclaredClasses0();
3416
3417 /**
3418 * Helper method to get the method name from arguments.
3419 */
3420 private String methodToString(String name, Class<?>[] argTypes) {
3421 StringBuilder sb = new StringBuilder();
3422 sb.append(getName() + "." + name + "(");
3423 if (argTypes != null) {
3424 sb.append(Arrays.stream(argTypes)
3425 .map(c -> (c == null) ? "null" : c.getName())
3426 .collect(Collectors.joining(",")));
3427 }
3428 sb.append(")");
3429 return sb.toString();
3430 }
3431
3432 /** use serialVersionUID from JDK 1.1 for interoperability */
3433 private static final long serialVersionUID = 3206093459760846163L;
3434
3435
3436 /**
3437 * Class Class is special cased within the Serialization Stream Protocol.
3438 *
3439 * A Class instance is written initially into an ObjectOutputStream in the
3440 * following format:
3441 * <pre>
3442 * {@code TC_CLASS} ClassDescriptor
3443 * A ClassDescriptor is a special cased serialization of
3444 * a {@code java.io.ObjectStreamClass} instance.
3445 * </pre>
3446 * A new handle is generated for the initial time the class descriptor
3447 * is written into the stream. Future references to the class descriptor
3448 * are written as references to the initial class descriptor instance.
3449 *
3450 * @see java.io.ObjectStreamClass
3451 */
3452 private static final ObjectStreamField[] serialPersistentFields =
3453 new ObjectStreamField[0];
3454
3455
3456 /**
3457 * Returns the assertion status that would be assigned to this
3458 * class if it were to be initialized at the time this method is invoked.
3459 * If this class has had its assertion status set, the most recent
3460 * setting will be returned; otherwise, if any package default assertion
3461 * status pertains to this class, the most recent setting for the most
3462 * specific pertinent package default assertion status is returned;
3463 * otherwise, if this class is not a system class (i.e., it has a
3464 * class loader) its class loader's default assertion status is returned;
3465 * otherwise, the system class default assertion status is returned.
3466 * <p>
3467 * Few programmers will have any need for this method; it is provided
3468 * for the benefit of the JRE itself. (It allows a class to determine at
3469 * the time that it is initialized whether assertions should be enabled.)
3470 * Note that this method is not guaranteed to return the actual
3471 * assertion status that was (or will be) associated with the specified
3472 * class when it was (or will be) initialized.
3473 *
3474 * @return the desired assertion status of the specified class.
3475 * @see java.lang.ClassLoader#setClassAssertionStatus
3476 * @see java.lang.ClassLoader#setPackageAssertionStatus
3477 * @see java.lang.ClassLoader#setDefaultAssertionStatus
3478 * @since 1.4
3479 */
3480 public boolean desiredAssertionStatus() {
3481 ClassLoader loader = getClassLoader0();
3482 // If the loader is null this is a system class, so ask the VM
3483 if (loader == null)
3484 return desiredAssertionStatus0(this);
3485
3486 // If the classloader has been initialized with the assertion
3487 // directives, ask it. Otherwise, ask the VM.
3488 synchronized(loader.assertionLock) {
3489 if (loader.classAssertionStatus != null) {
3490 return loader.desiredAssertionStatus(getName());
3491 }
3492 }
3493 return desiredAssertionStatus0(this);
3494 }
3495
3496 // Retrieves the desired assertion status of this class from the VM
3497 private static native boolean desiredAssertionStatus0(Class<?> clazz);
3498
3499 /**
3500 * Returns true if and only if this class was declared as an enum in the
3501 * source code.
3502 *
3503 * @return true if and only if this class was declared as an enum in the
3504 * source code
3505 * @since 1.5
3506 */
3507 public boolean isEnum() {
3508 // An enum must both directly extend java.lang.Enum and have
3509 // the ENUM bit set; classes for specialized enum constants
3510 // don't do the former.
3511 return (this.getModifiers() & ENUM) != 0 &&
3512 this.getSuperclass() == java.lang.Enum.class;
3513 }
3514
3515 // Fetches the factory for reflective objects
3516 private static ReflectionFactory getReflectionFactory() {
3517 if (reflectionFactory == null) {
3518 reflectionFactory =
3519 java.security.AccessController.doPrivileged
3520 (new ReflectionFactory.GetReflectionFactoryAction());
3521 }
3522 return reflectionFactory;
3523 }
3524 private static ReflectionFactory reflectionFactory;
3525
3526 /**
3527 * Returns the elements of this enum class or null if this
3528 * Class object does not represent an enum type.
3529 *
3530 * @return an array containing the values comprising the enum class
3531 * represented by this Class object in the order they're
3532 * declared, or null if this Class object does not
3533 * represent an enum type
3534 * @since 1.5
3535 */
3536 public T[] getEnumConstants() {
3537 T[] values = getEnumConstantsShared();
3538 return (values != null) ? values.clone() : null;
3539 }
3540
3541 /**
3542 * Returns the elements of this enum class or null if this
3543 * Class object does not represent an enum type;
3544 * identical to getEnumConstants except that the result is
3545 * uncloned, cached, and shared by all callers.
3546 */
3547 T[] getEnumConstantsShared() {
3548 T[] constants = enumConstants;
3549 if (constants == null) {
3550 if (!isEnum()) return null;
3551 try {
3552 final Method values = getMethod("values");
3553 java.security.AccessController.doPrivileged(
3554 new java.security.PrivilegedAction<>() {
3555 public Void run() {
3556 values.setAccessible(true);
3557 return null;
3558 }
3559 });
3560 @SuppressWarnings("unchecked")
3561 T[] temporaryConstants = (T[])values.invoke(null);
3562 enumConstants = constants = temporaryConstants;
3563 }
3564 // These can happen when users concoct enum-like classes
3565 // that don't comply with the enum spec.
3566 catch (InvocationTargetException | NoSuchMethodException |
3567 IllegalAccessException ex) { return null; }
3568 }
3569 return constants;
3570 }
3571 private transient volatile T[] enumConstants;
3572
3573 /**
3574 * Returns a map from simple name to enum constant. This package-private
3575 * method is used internally by Enum to implement
3576 * {@code public static <T extends Enum<T>> T valueOf(Class<T>, String)}
3577 * efficiently. Note that the map is returned by this method is
3578 * created lazily on first use. Typically it won't ever get created.
3579 */
3580 Map<String, T> enumConstantDirectory() {
3581 Map<String, T> directory = enumConstantDirectory;
3582 if (directory == null) {
3583 T[] universe = getEnumConstantsShared();
3584 if (universe == null)
3585 throw new IllegalArgumentException(
3586 getName() + " is not an enum type");
3587 directory = new HashMap<>((int)(universe.length / 0.75f) + 1);
3588 for (T constant : universe) {
3589 directory.put(((Enum<?>)constant).name(), constant);
3590 }
3591 enumConstantDirectory = directory;
3592 }
3593 return directory;
3594 }
3595 private transient volatile Map<String, T> enumConstantDirectory;
3596
3597 /**
3598 * Casts an object to the class or interface represented
3599 * by this {@code Class} object.
3600 *
3601 * @param obj the object to be cast
3602 * @return the object after casting, or null if obj is null
3603 *
3604 * @throws ClassCastException if the object is not
3605 * null and is not assignable to the type T.
3606 *
3607 * @since 1.5
3608 */
3609 @SuppressWarnings("unchecked")
3610 @HotSpotIntrinsicCandidate
3611 public T cast(Object obj) {
3612 if (obj != null && !isInstance(obj))
3613 throw new ClassCastException(cannotCastMsg(obj));
3614 return (T) obj;
3615 }
3616
3617 private String cannotCastMsg(Object obj) {
3618 return "Cannot cast " + obj.getClass().getName() + " to " + getName();
3619 }
3620
3621 /**
3622 * Casts this {@code Class} object to represent a subclass of the class
3623 * represented by the specified class object. Checks that the cast
3624 * is valid, and throws a {@code ClassCastException} if it is not. If
3625 * this method succeeds, it always returns a reference to this class object.
3626 *
3627 * <p>This method is useful when a client needs to "narrow" the type of
3628 * a {@code Class} object to pass it to an API that restricts the
3629 * {@code Class} objects that it is willing to accept. A cast would
3630 * generate a compile-time warning, as the correctness of the cast
3631 * could not be checked at runtime (because generic types are implemented
3632 * by erasure).
3633 *
3634 * @param <U> the type to cast this class object to
3635 * @param clazz the class of the type to cast this class object to
3636 * @return this {@code Class} object, cast to represent a subclass of
3637 * the specified class object.
3638 * @throws ClassCastException if this {@code Class} object does not
3639 * represent a subclass of the specified class (here "subclass" includes
3640 * the class itself).
3641 * @since 1.5
3642 */
3643 @SuppressWarnings("unchecked")
3644 public <U> Class<? extends U> asSubclass(Class<U> clazz) {
3645 if (clazz.isAssignableFrom(this))
3646 return (Class<? extends U>) this;
3647 else
3648 throw new ClassCastException(this.toString());
3649 }
3650
3651 /**
3652 * @throws NullPointerException {@inheritDoc}
3653 * @since 1.5
3654 */
3655 @SuppressWarnings("unchecked")
3656 public <A extends Annotation> A getAnnotation(Class<A> annotationClass) {
3657 Objects.requireNonNull(annotationClass);
3658
3659 return (A) annotationData().annotations.get(annotationClass);
3660 }
3661
3662 /**
3663 * {@inheritDoc}
3664 * @throws NullPointerException {@inheritDoc}
3665 * @since 1.5
3666 */
3667 @Override
3668 public boolean isAnnotationPresent(Class<? extends Annotation> annotationClass) {
3669 return GenericDeclaration.super.isAnnotationPresent(annotationClass);
3670 }
3671
3672 /**
3673 * @throws NullPointerException {@inheritDoc}
3674 * @since 1.8
3675 */
3676 @Override
3677 public <A extends Annotation> A[] getAnnotationsByType(Class<A> annotationClass) {
3678 Objects.requireNonNull(annotationClass);
3679
3680 AnnotationData annotationData = annotationData();
3681 return AnnotationSupport.getAssociatedAnnotations(annotationData.declaredAnnotations,
3682 this,
3683 annotationClass);
3684 }
3685
3686 /**
3687 * @since 1.5
3688 */
3689 public Annotation[] getAnnotations() {
3690 return AnnotationParser.toArray(annotationData().annotations);
3691 }
3692
3693 /**
3694 * @throws NullPointerException {@inheritDoc}
3695 * @since 1.8
3696 */
3697 @Override
3698 @SuppressWarnings("unchecked")
3699 public <A extends Annotation> A getDeclaredAnnotation(Class<A> annotationClass) {
3700 Objects.requireNonNull(annotationClass);
3701
3702 return (A) annotationData().declaredAnnotations.get(annotationClass);
3703 }
3704
3705 /**
3706 * @throws NullPointerException {@inheritDoc}
3707 * @since 1.8
3708 */
3709 @Override
3710 public <A extends Annotation> A[] getDeclaredAnnotationsByType(Class<A> annotationClass) {
3711 Objects.requireNonNull(annotationClass);
3712
3713 return AnnotationSupport.getDirectlyAndIndirectlyPresent(annotationData().declaredAnnotations,
3714 annotationClass);
3715 }
3716
3717 /**
3718 * @since 1.5
3719 */
3720 public Annotation[] getDeclaredAnnotations() {
3721 return AnnotationParser.toArray(annotationData().declaredAnnotations);
3722 }
3723
3724 // annotation data that might get invalidated when JVM TI RedefineClasses() is called
3725 private static class AnnotationData {
3726 final Map<Class<? extends Annotation>, Annotation> annotations;
3727 final Map<Class<? extends Annotation>, Annotation> declaredAnnotations;
3728
3729 // Value of classRedefinedCount when we created this AnnotationData instance
3730 final int redefinedCount;
3731
3732 AnnotationData(Map<Class<? extends Annotation>, Annotation> annotations,
3733 Map<Class<? extends Annotation>, Annotation> declaredAnnotations,
3734 int redefinedCount) {
3735 this.annotations = annotations;
3736 this.declaredAnnotations = declaredAnnotations;
3737 this.redefinedCount = redefinedCount;
3738 }
3739 }
3740
3741 // Annotations cache
3742 @SuppressWarnings("UnusedDeclaration")
3743 private transient volatile AnnotationData annotationData;
3744
3745 private AnnotationData annotationData() {
3746 while (true) { // retry loop
3747 AnnotationData annotationData = this.annotationData;
3748 int classRedefinedCount = this.classRedefinedCount;
3749 if (annotationData != null &&
3750 annotationData.redefinedCount == classRedefinedCount) {
3751 return annotationData;
3752 }
3753 // null or stale annotationData -> optimistically create new instance
3754 AnnotationData newAnnotationData = createAnnotationData(classRedefinedCount);
3755 // try to install it
3756 if (Atomic.casAnnotationData(this, annotationData, newAnnotationData)) {
3757 // successfully installed new AnnotationData
3758 return newAnnotationData;
3759 }
3760 }
3761 }
3762
3763 private AnnotationData createAnnotationData(int classRedefinedCount) {
3764 Map<Class<? extends Annotation>, Annotation> declaredAnnotations =
3765 AnnotationParser.parseAnnotations(getRawAnnotations(), getConstantPool(), this);
3766 Class<?> superClass = getSuperclass();
3767 Map<Class<? extends Annotation>, Annotation> annotations = null;
3768 if (superClass != null) {
3769 Map<Class<? extends Annotation>, Annotation> superAnnotations =
3770 superClass.annotationData().annotations;
3771 for (Map.Entry<Class<? extends Annotation>, Annotation> e : superAnnotations.entrySet()) {
3772 Class<? extends Annotation> annotationClass = e.getKey();
3773 if (AnnotationType.getInstance(annotationClass).isInherited()) {
3774 if (annotations == null) { // lazy construction
3775 annotations = new LinkedHashMap<>((Math.max(
3776 declaredAnnotations.size(),
3777 Math.min(12, declaredAnnotations.size() + superAnnotations.size())
3778 ) * 4 + 2) / 3
3779 );
3780 }
3781 annotations.put(annotationClass, e.getValue());
3782 }
3783 }
3784 }
3785 if (annotations == null) {
3786 // no inherited annotations -> share the Map with declaredAnnotations
3787 annotations = declaredAnnotations;
3788 } else {
3789 // at least one inherited annotation -> declared may override inherited
3790 annotations.putAll(declaredAnnotations);
3791 }
3792 return new AnnotationData(annotations, declaredAnnotations, classRedefinedCount);
3793 }
3794
3795 // Annotation types cache their internal (AnnotationType) form
3796
3797 @SuppressWarnings("UnusedDeclaration")
3798 private transient volatile AnnotationType annotationType;
3799
3800 boolean casAnnotationType(AnnotationType oldType, AnnotationType newType) {
3801 return Atomic.casAnnotationType(this, oldType, newType);
3802 }
3803
3804 AnnotationType getAnnotationType() {
3805 return annotationType;
3806 }
3807
3808 Map<Class<? extends Annotation>, Annotation> getDeclaredAnnotationMap() {
3809 return annotationData().declaredAnnotations;
3810 }
3811
3812 /* Backing store of user-defined values pertaining to this class.
3813 * Maintained by the ClassValue class.
3814 */
3815 transient ClassValue.ClassValueMap classValueMap;
3816
3817 /**
3818 * Returns an {@code AnnotatedType} object that represents the use of a
3819 * type to specify the superclass of the entity represented by this {@code
3820 * Class} object. (The <em>use</em> of type Foo to specify the superclass
3821 * in '... extends Foo' is distinct from the <em>declaration</em> of type
3822 * Foo.)
3823 *
3824 * <p> If this {@code Class} object represents a type whose declaration
3825 * does not explicitly indicate an annotated superclass, then the return
3826 * value is an {@code AnnotatedType} object representing an element with no
3827 * annotations.
3828 *
3829 * <p> If this {@code Class} represents either the {@code Object} class, an
3830 * interface type, an array type, a primitive type, or void, the return
3831 * value is {@code null}.
3832 *
3833 * @return an object representing the superclass
3834 * @since 1.8
3835 */
3836 public AnnotatedType getAnnotatedSuperclass() {
3837 if (this == Object.class ||
3838 isInterface() ||
3839 isArray() ||
3840 isPrimitive() ||
3841 this == Void.TYPE) {
3842 return null;
3843 }
3844
3845 return TypeAnnotationParser.buildAnnotatedSuperclass(getRawTypeAnnotations(), getConstantPool(), this);
3846 }
3847
3848 /**
3849 * Returns an array of {@code AnnotatedType} objects that represent the use
3850 * of types to specify superinterfaces of the entity represented by this
3851 * {@code Class} object. (The <em>use</em> of type Foo to specify a
3852 * superinterface in '... implements Foo' is distinct from the
3853 * <em>declaration</em> of type Foo.)
3854 *
3855 * <p> If this {@code Class} object represents a class, the return value is
3856 * an array containing objects representing the uses of interface types to
3857 * specify interfaces implemented by the class. The order of the objects in
3858 * the array corresponds to the order of the interface types used in the
3859 * 'implements' clause of the declaration of this {@code Class} object.
3860 *
3861 * <p> If this {@code Class} object represents an interface, the return
3862 * value is an array containing objects representing the uses of interface
3863 * types to specify interfaces directly extended by the interface. The
3864 * order of the objects in the array corresponds to the order of the
3865 * interface types used in the 'extends' clause of the declaration of this
3866 * {@code Class} object.
3867 *
3868 * <p> If this {@code Class} object represents a class or interface whose
3869 * declaration does not explicitly indicate any annotated superinterfaces,
3870 * the return value is an array of length 0.
3871 *
3872 * <p> If this {@code Class} object represents either the {@code Object}
3873 * class, an array type, a primitive type, or void, the return value is an
3874 * array of length 0.
3875 *
3876 * @return an array representing the superinterfaces
3877 * @since 1.8
3878 */
3879 public AnnotatedType[] getAnnotatedInterfaces() {
3880 return TypeAnnotationParser.buildAnnotatedInterfaces(getRawTypeAnnotations(), getConstantPool(), this);
3881 }
3882
3883 private native Class<?> getNestHost0();
3884
3885 /**
3886 * Returns the nest host of the <a href=#nest>nest</a> to which the class
3887 * or interface represented by this {@code Class} object belongs.
3888 * Every class and interface is a member of exactly one nest.
3889 * A class or interface that is not recorded as belonging to a nest
3890 * belongs to the nest consisting only of itself, and is the nest
3891 * host.
3892 *
3893 * <p>Each of the {@code Class} objects representing array types,
3894 * primitive types, and {@code void} returns {@code this} to indicate
3895 * that the represented entity belongs to the nest consisting only of
3896 * itself, and is the nest host.
3897 *
3898 * <p>If there is a {@linkplain LinkageError linkage error} accessing
3899 * the nest host, or if this class or interface is not enumerated as
3900 * a member of the nest by the nest host, then it is considered to belong
3901 * to its own nest and {@code this} is returned as the host.
3902 *
3903 * @apiNote A {@code class} file of version 55.0 or greater may record the
3904 * host of the nest to which it belongs by using the {@code NestHost}
3905 * attribute (JVMS 4.7.28). Alternatively, a {@code class} file of
3906 * version 55.0 or greater may act as a nest host by enumerating the nest's
3907 * other members with the
3908 * {@code NestMembers} attribute (JVMS 4.7.29).
3909 * A {@code class} file of version 54.0 or lower does not use these
3910 * attributes.
3911 *
3912 * @return the nest host of this class or interface
3913 *
3914 * @throws SecurityException
3915 * If the returned class is not the current class, and
3916 * if a security manager, <i>s</i>, is present and the caller's
3917 * class loader is not the same as or an ancestor of the class
3918 * loader for the returned class and invocation of {@link
3919 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
3920 * denies access to the package of the returned class
3921 * @since 11
3922 * @jvms 4.7.28 and 4.7.29 NestHost and NestMembers attributes
3923 * @jvms 5.4.4 Access Control
3924 */
3925 @CallerSensitive
3926 public Class<?> getNestHost() {
3927 if (isPrimitive() || isArray()) {
3928 return this;
3929 }
3930 Class<?> host;
3931 try {
3932 host = getNestHost0();
3933 } catch (LinkageError e) {
3934 // if we couldn't load our nest-host then we
3935 // act as-if we have no nest-host attribute
3936 return this;
3937 }
3938 // if null then nest membership validation failed, so we
3939 // act as-if we have no nest-host attribute
3940 if (host == null || host == this) {
3941 return this;
3942 }
3943 // returning a different class requires a security check
3944 SecurityManager sm = System.getSecurityManager();
3945 if (sm != null) {
3946 checkPackageAccess(sm,
3947 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
3948 }
3949 return host;
3950 }
3951
3952 /**
3953 * Determines if the given {@code Class} is a nestmate of the
3954 * class or interface represented by this {@code Class} object.
3955 * Two classes or interfaces are nestmates
3956 * if they have the same {@linkplain #getNestHost() nest host}.
3957 *
3958 * @param c the class to check
3959 * @return {@code true} if this class and {@code c} are members of
3960 * the same nest; and {@code false} otherwise.
3961 *
3962 * @since 11
3963 */
3964 public boolean isNestmateOf(Class<?> c) {
3965 if (this == c) {
3966 return true;
3967 }
3968 if (isPrimitive() || isArray() ||
3969 c.isPrimitive() || c.isArray()) {
3970 return false;
3971 }
3972 try {
3973 return getNestHost0() == c.getNestHost0();
3974 } catch (LinkageError e) {
3975 return false;
3976 }
3977 }
3978
3979 private native Class<?>[] getNestMembers0();
3980
3981 /**
3982 * Returns an array containing {@code Class} objects representing all the
3983 * classes and interfaces that are members of the nest to which the class
3984 * or interface represented by this {@code Class} object belongs.
3985 * The {@linkplain #getNestHost() nest host} of that nest is the zeroth
3986 * element of the array. Subsequent elements represent any classes or
3987 * interfaces that are recorded by the nest host as being members of
3988 * the nest; the order of such elements is unspecified. Duplicates are
3989 * permitted.
3990 * If the nest host of that nest does not enumerate any members, then the
3991 * array has a single element containing {@code this}.
3992 *
3993 * <p>Each of the {@code Class} objects representing array types,
3994 * primitive types, and {@code void} returns an array containing only
3995 * {@code this}.
3996 *
3997 * <p>This method validates that, for each class or interface which is
3998 * recorded as a member of the nest by the nest host, that class or
3999 * interface records itself as a member of that same nest. Any exceptions
4000 * that occur during this validation are rethrown by this method.
4001 *
4002 * @return an array of all classes and interfaces in the same nest as
4003 * this class
4004 *
4005 * @throws LinkageError
4006 * If there is any problem loading or validating a nest member or
4007 * its nest host
4008 * @throws SecurityException
4009 * If any returned class is not the current class, and
4010 * if a security manager, <i>s</i>, is present and the caller's
4011 * class loader is not the same as or an ancestor of the class
4012 * loader for that returned class and invocation of {@link
4013 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
4014 * denies access to the package of that returned class
4015 *
4016 * @since 11
4017 * @see #getNestHost()
4018 */
4019 @CallerSensitive
4020 public Class<?>[] getNestMembers() {
4021 if (isPrimitive() || isArray()) {
4022 return new Class<?>[] { this };
4023 }
4024 Class<?>[] members = getNestMembers0();
4025 // Can't actually enable this due to bootstrapping issues
4026 // assert(members.length != 1 || members[0] == this); // expected invariant from VM
4027
4028 if (members.length > 1) {
4029 // If we return anything other than the current class we need
4030 // a security check
4031 SecurityManager sm = System.getSecurityManager();
4032 if (sm != null) {
4033 checkPackageAccess(sm,
4034 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
4035 }
4036 }
4037 return members;
4038 }
4039
4040 /**
4041 * Returns the type descriptor string for this class.
4042 * <p>
4043 * Note that this is not a strict inverse of {@link #forName};
4044 * distinct classes which share a common name but have different class loaders
4045 * will have identical descriptor strings.
4046 *
4047 * @return the type descriptor representation
4048 * @jvms 4.3.2 Field Descriptors
4049 * @since 12
4050 */
4051 @Override
4052 public String descriptorString() {
4053 if (isPrimitive())
4054 return Wrapper.forPrimitiveType(this).basicTypeString();
4055 else if (isArray()) {
4056 return "[" + componentType.descriptorString();
4057 }
4058 else {
4059 return "L" + getName().replace('.', '/') + ";";
4060 }
4061 }
4062
4063 /**
4064 * Returns the component type of this {@code Class}, if it describes
4065 * an array type, or {@code null} otherwise.
4066 *
4067 * @implSpec
4068 * Equivalent to {@link Class#getComponentType()}.
4069 *
4070 * @return a {@code Class} describing the component type, or {@code null}
4071 * if this {@code Class} does not describe an array type
4072 * @since 12
4073 */
4074 @Override
4075 public Class<?> componentType() {
4076 return isArray() ? componentType : null;
4077 }
4078
4079 /**
4080 * Returns a {@code Class} for an array type whose component type
4081 * is described by this {@linkplain Class}.
4082 *
4083 * @return a {@code Class} describing the array type
4084 * @since 12
4085 */
4086 @Override
4087 public Class<?> arrayType() {
4088 return Array.newInstance(this, 0).getClass();
4089 }
4090
4091 /**
4092 * Returns a nominal descriptor for this instance, if one can be
4093 * constructed, or an empty {@link Optional} if one cannot be.
4094 *
4095 * @return An {@link Optional} containing the resulting nominal descriptor,
4096 * or an empty {@link Optional} if one cannot be constructed.
4097 * @since 12
4098 */
4099 @Override
4100 public Optional<ClassDesc> describeConstable() {
4101 return Optional.of(ClassDesc.ofDescriptor(descriptorString()));
4102 }
4103 }