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.RecordComponent;
50 import java.lang.reflect.Type;
51 import java.lang.reflect.TypeVariable;
52 import java.lang.constant.Constable;
53 import java.net.URL;
54 import java.security.AccessController;
55 import java.security.PrivilegedAction;
56 import java.util.ArrayList;
57 import java.util.Arrays;
58 import java.util.Collection;
59 import java.util.HashMap;
60 import java.util.LinkedHashMap;
61 import java.util.LinkedHashSet;
62 import java.util.List;
63 import java.util.Map;
64 import java.util.Objects;
65 import java.util.Optional;
66 import java.util.StringJoiner;
67 import java.util.stream.Stream;
68 import java.util.stream.Collectors;
69
70 import jdk.internal.HotSpotIntrinsicCandidate;
71 import jdk.internal.loader.BootLoader;
72 import jdk.internal.loader.BuiltinClassLoader;
73 import jdk.internal.misc.Unsafe;
74 import jdk.internal.module.Resources;
75 import jdk.internal.reflect.CallerSensitive;
76 import jdk.internal.reflect.ConstantPool;
77 import jdk.internal.reflect.Reflection;
78 import jdk.internal.reflect.ReflectionFactory;
79 import jdk.internal.vm.annotation.ForceInline;
80 import sun.invoke.util.Wrapper;
81 import sun.reflect.generics.factory.CoreReflectionFactory;
82 import sun.reflect.generics.factory.GenericsFactory;
83 import sun.reflect.generics.repository.ClassRepository;
84 import sun.reflect.generics.repository.MethodRepository;
85 import sun.reflect.generics.repository.ConstructorRepository;
86 import sun.reflect.generics.scope.ClassScope;
87 import sun.security.util.SecurityConstants;
88 import sun.reflect.annotation.*;
89 import sun.reflect.misc.ReflectUtil;
90
91 /**
92 * Instances of the class {@code Class} represent classes and interfaces
93 * in a running Java application. An enum type is a kind of class and an
94 * annotation type is a kind of interface. Every array also
95 * belongs to a class that is reflected as a {@code Class} object
96 * that is shared by all arrays with the same element type and number
97 * of dimensions. The primitive Java types ({@code boolean},
98 * {@code byte}, {@code char}, {@code short},
99 * {@code int}, {@code long}, {@code float}, and
100 * {@code double}), and the keyword {@code void} are also
101 * represented as {@code Class} objects.
102 *
103 * <p> {@code Class} has no public constructor. Instead a {@code Class}
104 * object is constructed automatically by the Java Virtual Machine
105 * when a class loader invokes one of the
106 * {@link ClassLoader#defineClass(String,byte[], int,int) defineClass} methods
107 * and passes the bytes of a {@code class} file.
108 *
109 * <p> The methods of class {@code Class} expose many characteristics of a
110 * class or interface. Most characteristics are derived from the {@code class}
111 * file that the class loader passed to the Java Virtual Machine. A few
112 * characteristics are determined by the class loading environment at run time,
113 * such as the module returned by {@link #getModule() getModule()}.
114 *
115 * <p> Some methods of class {@code Class} expose whether the declaration of
116 * a class or interface in Java source code was <em>enclosed</em> within
117 * another declaration. Other methods describe how a class or interface
118 * is situated in a <em>nest</em>. A <a id="nest">nest</a> is a set of
119 * classes and interfaces, in the same run-time package, that
120 * allow mutual access to their {@code private} members.
121 * The classes and interfaces are known as <em>nestmates</em>.
122 * One nestmate acts as the
123 * <em>nest host</em>, and enumerates the other nestmates which
124 * belong to the nest; each of them in turn records it as the nest host.
125 * The classes and interfaces which belong to a nest, including its host, are
126 * determined when
127 * {@code class} files are generated, for example, a Java compiler
128 * will typically record a top-level class as the host of a nest where the
129 * other members are the classes and interfaces whose declarations are
130 * enclosed within the top-level class declaration.
131 *
132 * <p> The following example uses a {@code Class} object to print the
133 * class name of an object:
134 *
135 * <blockquote><pre>
136 * void printClassName(Object obj) {
137 * System.out.println("The class of " + obj +
138 * " is " + obj.getClass().getName());
139 * }
140 * </pre></blockquote>
141 *
142 * <p> It is also possible to get the {@code Class} object for a named
143 * type (or for void) using a class literal. See Section 15.8.2 of
144 * <cite>The Java™ Language Specification</cite>.
145 * For example:
146 *
147 * <blockquote>
148 * {@code System.out.println("The name of class Foo is: "+Foo.class.getName());}
149 * </blockquote>
150 *
151 * @param <T> the type of the class modeled by this {@code Class}
152 * object. For example, the type of {@code String.class} is {@code
153 * Class<String>}. Use {@code Class<?>} if the class being modeled is
154 * unknown.
155 *
156 * @author unascribed
157 * @see java.lang.ClassLoader#defineClass(byte[], int, int)
158 * @since 1.0
159 */
160 public final class Class<T> implements java.io.Serializable,
161 GenericDeclaration,
162 Type,
163 AnnotatedElement,
164 TypeDescriptor.OfField<Class<?>>,
165 Constable {
166 private static final int ANNOTATION= 0x00002000;
167 private static final int ENUM = 0x00004000;
168 private static final int SYNTHETIC = 0x00001000;
169
170 private static native void registerNatives();
171 static {
172 registerNatives();
173 }
174
175 /*
176 * Private constructor. Only the Java Virtual Machine creates Class objects.
177 * This constructor is not used and prevents the default constructor being
178 * generated.
179 */
180 private Class(ClassLoader loader, Class<?> arrayComponentType) {
181 // Initialize final field for classLoader. The initialization value of non-null
182 // prevents future JIT optimizations from assuming this final field is null.
183 classLoader = loader;
184 componentType = arrayComponentType;
185 }
186
187 /**
188 * Converts the object to a string. The string representation is the
189 * string "class" or "interface", followed by a space, and then by the
190 * fully qualified name of the class in the format returned by
191 * {@code getName}. If this {@code Class} object represents a
192 * primitive type, this method returns the name of the primitive type. If
193 * this {@code Class} object represents void this method returns
194 * "void". If this {@code Class} object represents an array type,
195 * this method returns "class " followed by {@code getName}.
196 *
197 * @return a string representation of this class object.
198 */
199 public String toString() {
200 return (isInterface() ? "interface " : (isPrimitive() ? "" : "class "))
201 + getName();
202 }
203
204 /**
205 * Returns a string describing this {@code Class}, including
206 * information about modifiers and type parameters.
207 *
208 * The string is formatted as a list of type modifiers, if any,
209 * followed by the kind of type (empty string for primitive types
210 * and {@code class}, {@code enum}, {@code interface}, or
211 * <code>@</code>{@code interface}, as appropriate), followed
212 * by the type's name, followed by an angle-bracketed
213 * comma-separated list of the type's type parameters, if any,
214 * including informative bounds on the type parameters, if any.
215 *
216 * A space is used to separate modifiers from one another and to
217 * separate any modifiers from the kind of type. The modifiers
218 * occur in canonical order. If there are no type parameters, the
219 * type parameter list is elided.
220 *
221 * For an array type, the string starts with the type name,
222 * followed by an angle-bracketed comma-separated list of the
223 * type's type parameters, if any, followed by a sequence of
224 * {@code []} characters, one set of brackets per dimension of
225 * the array.
226 *
227 * <p>Note that since information about the runtime representation
228 * of a type is being generated, modifiers not present on the
229 * originating source code or illegal on the originating source
230 * code may be present.
231 *
232 * @return a string describing this {@code Class}, including
233 * information about modifiers and type parameters
234 *
235 * @since 1.8
236 */
237 public String toGenericString() {
238 if (isPrimitive()) {
239 return toString();
240 } else {
241 StringBuilder sb = new StringBuilder();
242 Class<?> component = this;
243 int arrayDepth = 0;
244
245 if (isArray()) {
246 do {
247 arrayDepth++;
248 component = component.getComponentType();
249 } while (component.isArray());
250 sb.append(component.getName());
251 } else {
252 // Class modifiers are a superset of interface modifiers
253 int modifiers = getModifiers() & Modifier.classModifiers();
254 if (modifiers != 0) {
255 sb.append(Modifier.toString(modifiers));
256 sb.append(' ');
257 }
258
259 if (isAnnotation()) {
260 sb.append('@');
261 }
262 if (isInterface()) { // Note: all annotation types are interfaces
263 sb.append("interface");
264 } else {
265 if (isEnum())
266 sb.append("enum");
267 else
268 sb.append("class");
269 }
270 sb.append(' ');
271 sb.append(getName());
272 }
273
274 TypeVariable<?>[] typeparms = component.getTypeParameters();
275 if (typeparms.length > 0) {
276 sb.append(Arrays.stream(typeparms)
277 .map(Class::typeVarBounds)
278 .collect(Collectors.joining(",", "<", ">")));
279 }
280
281 if (arrayDepth > 0) sb.append("[]".repeat(arrayDepth));
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 * @throws LinkageError if the linkage fails
326 * @throws ExceptionInInitializerError if the initialization provoked
327 * by this method fails
328 * @throws ClassNotFoundException if the class cannot be located
329 *
330 * @jls 12.2 Loading of Classes and Interfaces
331 * @jls 12.3 Linking of Classes and Interfaces
332 * @jls 12.4 Initialization of Classes and Interfaces
333 */
334 @CallerSensitive
335 public static Class<?> forName(String className)
336 throws ClassNotFoundException {
337 Class<?> caller = Reflection.getCallerClass();
338 return forName0(className, true, ClassLoader.getClassLoader(caller), caller);
339 }
340
341
342 /**
343 * Returns the {@code Class} object associated with the class or
344 * interface with the given string name, using the given class loader.
345 * Given the fully qualified name for a class or interface (in the same
346 * format returned by {@code getName}) this method attempts to
347 * locate and load the class or interface. The specified class
348 * loader is used to load the class or interface. If the parameter
349 * {@code loader} is null, the class is loaded through the bootstrap
350 * class loader. The class is initialized only if the
351 * {@code initialize} parameter is {@code true} and if it has
352 * not been initialized earlier.
353 *
354 * <p> If {@code name} denotes a primitive type or void, an attempt
355 * will be made to locate a user-defined class in the unnamed package whose
356 * name is {@code name}. Therefore, this method cannot be used to
357 * obtain any of the {@code Class} objects representing primitive
358 * types or void.
359 *
360 * <p> If {@code name} denotes an array class, the component type of
361 * the array class is loaded but not initialized.
362 *
363 * <p> For example, in an instance method the expression:
364 *
365 * <blockquote>
366 * {@code Class.forName("Foo")}
367 * </blockquote>
368 *
369 * is equivalent to:
370 *
371 * <blockquote>
372 * {@code Class.forName("Foo", true, this.getClass().getClassLoader())}
373 * </blockquote>
374 *
375 * Note that this method throws errors related to loading, linking or
376 * initializing as specified in Sections 12.2, 12.3 and 12.4 of <em>The
377 * Java Language Specification</em>.
378 * Note that this method does not check whether the requested class
379 * is accessible to its caller.
380 *
381 * @param name fully qualified name of the desired class
382 * @param initialize if {@code true} the class will be initialized (which implies linking).
383 * See Section 12.4 of <em>The Java Language Specification</em>.
384 * @param loader class loader from which the class must be loaded
385 * @return class object representing the desired class
386 *
387 * @throws LinkageError if the linkage fails
388 * @throws ExceptionInInitializerError if the initialization provoked
389 * by this method fails
390 * @throws ClassNotFoundException if the class cannot be located by
391 * the specified class loader
392 * @throws SecurityException
393 * if a security manager is present, and the {@code loader} is
394 * {@code null}, and the caller's class loader is not
395 * {@code null}, and the caller does not have the
396 * {@link RuntimePermission}{@code ("getClassLoader")}
397 *
398 * @see java.lang.Class#forName(String)
399 * @see java.lang.ClassLoader
400 *
401 * @jls 12.2 Loading of Classes and Interfaces
402 * @jls 12.3 Linking of Classes and Interfaces
403 * @jls 12.4 Initialization of Classes and Interfaces
404 * @since 1.2
405 */
406 @CallerSensitive
407 public static Class<?> forName(String name, boolean initialize,
408 ClassLoader loader)
409 throws ClassNotFoundException
410 {
411 Class<?> caller = null;
412 SecurityManager sm = System.getSecurityManager();
413 if (sm != null) {
414 // Reflective call to get caller class is only needed if a security manager
415 // is present. Avoid the overhead of making this call otherwise.
416 caller = Reflection.getCallerClass();
417 if (loader == null) {
418 ClassLoader ccl = ClassLoader.getClassLoader(caller);
419 if (ccl != null) {
420 sm.checkPermission(
421 SecurityConstants.GET_CLASSLOADER_PERMISSION);
422 }
423 }
424 }
425 return forName0(name, initialize, loader, caller);
426 }
427
428 /** Called after security check for system loader access checks have been made. */
429 private static native Class<?> forName0(String name, boolean initialize,
430 ClassLoader loader,
431 Class<?> caller)
432 throws ClassNotFoundException;
433
434
435 /**
436 * Returns the {@code Class} with the given <a href="ClassLoader.html#binary-name">
437 * binary name</a> in the given module.
438 *
439 * <p> This method attempts to locate and load the class or interface.
440 * It does not link the class, and does not run the class initializer.
441 * If the class is not found, this method returns {@code null}. </p>
442 *
443 * <p> If the class loader of the given module defines other modules and
444 * the given name is a class defined in a different module, this method
445 * returns {@code null} after the class is loaded. </p>
446 *
447 * <p> This method does not check whether the requested class is
448 * accessible to its caller. </p>
449 *
450 * @apiNote
451 * This method returns {@code null} on failure rather than
452 * throwing a {@link ClassNotFoundException}, as is done by
453 * the {@link #forName(String, boolean, ClassLoader)} method.
454 * The security check is a stack-based permission check if the caller
455 * loads a class in another module.
456 *
457 * @param module A module
458 * @param name The <a href="ClassLoader.html#binary-name">binary name</a>
459 * of the class
460 * @return {@code Class} object of the given name defined in the given module;
461 * {@code null} if not found.
462 *
463 * @throws NullPointerException if the given module or name is {@code null}
464 *
465 * @throws LinkageError if the linkage fails
466 *
467 * @throws SecurityException
468 * <ul>
469 * <li> if the caller is not the specified module and
470 * {@code RuntimePermission("getClassLoader")} permission is denied; or</li>
471 * <li> access to the module content is denied. For example,
472 * permission check will be performed when a class loader calls
473 * {@link ModuleReader#open(String)} to read the bytes of a class file
474 * in a module.</li>
475 * </ul>
476 *
477 * @jls 12.2 Loading of Classes and Interfaces
478 * @jls 12.3 Linking of Classes and Interfaces
479 * @since 9
480 * @spec JPMS
481 */
482 @CallerSensitive
483 public static Class<?> forName(Module module, String name) {
484 Objects.requireNonNull(module);
485 Objects.requireNonNull(name);
486
487 ClassLoader cl;
488 SecurityManager sm = System.getSecurityManager();
489 if (sm != null) {
490 Class<?> caller = Reflection.getCallerClass();
491 if (caller != null && caller.getModule() != module) {
492 // if caller is null, Class.forName is the last java frame on the stack.
493 // java.base has all permissions
494 sm.checkPermission(SecurityConstants.GET_CLASSLOADER_PERMISSION);
495 }
496 PrivilegedAction<ClassLoader> pa = module::getClassLoader;
497 cl = AccessController.doPrivileged(pa);
498 } else {
499 cl = module.getClassLoader();
500 }
501
502 if (cl != null) {
503 return cl.loadClass(module, name);
504 } else {
505 return BootLoader.loadClass(module, name);
506 }
507 }
508
509 /**
510 * Creates a new instance of the class represented by this {@code Class}
511 * object. The class is instantiated as if by a {@code new}
512 * expression with an empty argument list. The class is initialized if it
513 * has not already been initialized.
514 *
515 * @deprecated This method propagates any exception thrown by the
516 * nullary constructor, including a checked exception. Use of
517 * this method effectively bypasses the compile-time exception
518 * checking that would otherwise be performed by the compiler.
519 * The {@link
520 * java.lang.reflect.Constructor#newInstance(java.lang.Object...)
521 * Constructor.newInstance} method avoids this problem by wrapping
522 * any exception thrown by the constructor in a (checked) {@link
523 * java.lang.reflect.InvocationTargetException}.
524 *
525 * <p>The call
526 *
527 * <pre>{@code
528 * clazz.newInstance()
529 * }</pre>
530 *
531 * can be replaced by
532 *
533 * <pre>{@code
534 * clazz.getDeclaredConstructor().newInstance()
535 * }</pre>
536 *
537 * The latter sequence of calls is inferred to be able to throw
538 * the additional exception types {@link
539 * InvocationTargetException} and {@link
540 * NoSuchMethodException}. Both of these exception types are
541 * subclasses of {@link ReflectiveOperationException}.
542 *
543 * @return a newly allocated instance of the class represented by this
544 * object.
545 * @throws IllegalAccessException if the class or its nullary
546 * constructor is not accessible.
547 * @throws InstantiationException
548 * if this {@code Class} represents an abstract class,
549 * an interface, an array class, a primitive type, or void;
550 * or if the class has no nullary constructor;
551 * or if the instantiation fails for some other reason.
552 * @throws ExceptionInInitializerError if the initialization
553 * provoked by this method fails.
554 * @throws SecurityException
555 * If a security manager, <i>s</i>, is present and
556 * the caller's class loader is not the same as or an
557 * ancestor of the class loader for the current class and
558 * invocation of {@link SecurityManager#checkPackageAccess
559 * s.checkPackageAccess()} denies access to the package
560 * of this class.
561 */
562 @CallerSensitive
563 @Deprecated(since="9")
564 public T newInstance()
565 throws InstantiationException, IllegalAccessException
566 {
567 SecurityManager sm = System.getSecurityManager();
568 if (sm != null) {
569 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), false);
570 }
571
572 // Constructor lookup
573 Constructor<T> tmpConstructor = cachedConstructor;
574 if (tmpConstructor == null) {
575 if (this == Class.class) {
576 throw new IllegalAccessException(
577 "Can not call newInstance() on the Class for java.lang.Class"
578 );
579 }
580 try {
581 Class<?>[] empty = {};
582 final Constructor<T> c = getReflectionFactory().copyConstructor(
583 getConstructor0(empty, Member.DECLARED));
584 // Disable accessibility checks on the constructor
585 // access check is done with the true caller
586 java.security.AccessController.doPrivileged(
587 new java.security.PrivilegedAction<>() {
588 public Void run() {
589 c.setAccessible(true);
590 return null;
591 }
592 });
593 cachedConstructor = tmpConstructor = c;
594 } catch (NoSuchMethodException e) {
595 throw (InstantiationException)
596 new InstantiationException(getName()).initCause(e);
597 }
598 }
599
600 try {
601 Class<?> caller = Reflection.getCallerClass();
602 return getReflectionFactory().newInstance(tmpConstructor, null, caller);
603 } catch (InvocationTargetException e) {
604 Unsafe.getUnsafe().throwException(e.getTargetException());
605 // Not reached
606 return null;
607 }
608 }
609
610 private transient volatile Constructor<T> cachedConstructor;
611
612 /**
613 * Determines if the specified {@code Object} is assignment-compatible
614 * with the object represented by this {@code Class}. This method is
615 * the dynamic equivalent of the Java language {@code instanceof}
616 * operator. The method returns {@code true} if the specified
617 * {@code Object} argument is non-null and can be cast to the
618 * reference type represented by this {@code Class} object without
619 * raising a {@code ClassCastException.} It returns {@code false}
620 * otherwise.
621 *
622 * <p> Specifically, if this {@code Class} object represents a
623 * declared class, this method returns {@code true} if the specified
624 * {@code Object} argument is an instance of the represented class (or
625 * of any of its subclasses); it returns {@code false} otherwise. If
626 * this {@code Class} object represents an array class, this method
627 * returns {@code true} if the specified {@code Object} argument
628 * can be converted to an object of the array class by an identity
629 * conversion or by a widening reference conversion; it returns
630 * {@code false} otherwise. If this {@code Class} object
631 * represents an interface, this method returns {@code true} if the
632 * class or any superclass of the specified {@code Object} argument
633 * implements this interface; it returns {@code false} otherwise. If
634 * this {@code Class} object represents a primitive type, this method
635 * returns {@code false}.
636 *
637 * @param obj the object to check
638 * @return true if {@code obj} is an instance of this class
639 *
640 * @since 1.1
641 */
642 @HotSpotIntrinsicCandidate
643 public native boolean isInstance(Object obj);
644
645
646 /**
647 * Determines if the class or interface represented by this
648 * {@code Class} object is either the same as, or is a superclass or
649 * superinterface of, the class or interface represented by the specified
650 * {@code Class} parameter. It returns {@code true} if so;
651 * otherwise it returns {@code false}. If this {@code Class}
652 * object represents a primitive type, this method returns
653 * {@code true} if the specified {@code Class} parameter is
654 * exactly this {@code Class} object; otherwise it returns
655 * {@code false}.
656 *
657 * <p> Specifically, this method tests whether the type represented by the
658 * specified {@code Class} parameter can be converted to the type
659 * represented by this {@code Class} object via an identity conversion
660 * or via a widening reference conversion. See <em>The Java Language
661 * Specification</em>, sections 5.1.1 and 5.1.4 , for details.
662 *
663 * @param cls the {@code Class} object to be checked
664 * @return the {@code boolean} value indicating whether objects of the
665 * type {@code cls} can be assigned to objects of this class
666 * @throws NullPointerException if the specified Class parameter is
667 * null.
668 * @since 1.1
669 */
670 @HotSpotIntrinsicCandidate
671 public native boolean isAssignableFrom(Class<?> cls);
672
673
674 /**
675 * Determines if the specified {@code Class} object represents an
676 * interface type.
677 *
678 * @return {@code true} if this object represents an interface;
679 * {@code false} otherwise.
680 */
681 @HotSpotIntrinsicCandidate
682 public native boolean isInterface();
683
684
685 /**
686 * Determines if this {@code Class} object represents an array class.
687 *
688 * @return {@code true} if this object represents an array class;
689 * {@code false} otherwise.
690 * @since 1.1
691 */
692 @HotSpotIntrinsicCandidate
693 public native boolean isArray();
694
695
696 /**
697 * Determines if the specified {@code Class} object represents a
698 * primitive type.
699 *
700 * <p> There are nine predefined {@code Class} objects to represent
701 * the eight primitive types and void. These are created by the Java
702 * Virtual Machine, and have the same names as the primitive types that
703 * they represent, namely {@code boolean}, {@code byte},
704 * {@code char}, {@code short}, {@code int},
705 * {@code long}, {@code float}, and {@code double}.
706 *
707 * <p> These objects may only be accessed via the following public static
708 * final variables, and are the only {@code Class} objects for which
709 * this method returns {@code true}.
710 *
711 * @return true if and only if this class represents a primitive type
712 *
713 * @see java.lang.Boolean#TYPE
714 * @see java.lang.Character#TYPE
715 * @see java.lang.Byte#TYPE
716 * @see java.lang.Short#TYPE
717 * @see java.lang.Integer#TYPE
718 * @see java.lang.Long#TYPE
719 * @see java.lang.Float#TYPE
720 * @see java.lang.Double#TYPE
721 * @see java.lang.Void#TYPE
722 * @since 1.1
723 */
724 @HotSpotIntrinsicCandidate
725 public native boolean isPrimitive();
726
727 /**
728 * Returns true if this {@code Class} object represents an annotation
729 * type. Note that if this method returns true, {@link #isInterface()}
730 * would also return true, as all annotation types are also interfaces.
731 *
732 * @return {@code true} if this class object represents an annotation
733 * type; {@code false} otherwise
734 * @since 1.5
735 */
736 public boolean isAnnotation() {
737 return (getModifiers() & ANNOTATION) != 0;
738 }
739
740 /**
741 * Returns {@code true} if this class is a synthetic class;
742 * returns {@code false} otherwise.
743 * @return {@code true} if and only if this class is a synthetic class as
744 * defined by the Java Language Specification.
745 * @jls 13.1 The Form of a Binary
746 * @since 1.5
747 */
748 public boolean isSynthetic() {
749 return (getModifiers() & SYNTHETIC) != 0;
750 }
751
752 /**
753 * Returns the name of the entity (class, interface, array class,
754 * primitive type, or void) represented by this {@code Class} object,
755 * as a {@code String}.
756 *
757 * <p> If this class object represents a reference type that is not an
758 * array type then the binary name of the class is returned, as specified
759 * by
760 * <cite>The Java™ Language Specification</cite>.
761 *
762 * <p> If this class object represents a primitive type or void, then the
763 * name returned is a {@code String} equal to the Java language
764 * keyword corresponding to the primitive type or void.
765 *
766 * <p> If this class object represents a class of arrays, then the internal
767 * form of the name consists of the name of the element type preceded by
768 * one or more '{@code [}' characters representing the depth of the array
769 * nesting. The encoding of element type names is as follows:
770 *
771 * <blockquote><table class="striped">
772 * <caption style="display:none">Element types and encodings</caption>
773 * <thead>
774 * <tr><th scope="col"> Element Type <th scope="col"> Encoding
775 * </thead>
776 * <tbody style="text-align:left">
777 * <tr><th scope="row"> boolean <td style="text-align:center"> Z
778 * <tr><th scope="row"> byte <td style="text-align:center"> B
779 * <tr><th scope="row"> char <td style="text-align:center"> C
780 * <tr><th scope="row"> class or interface
781 * <td style="text-align:center"> L<i>classname</i>;
782 * <tr><th scope="row"> double <td style="text-align:center"> D
783 * <tr><th scope="row"> float <td style="text-align:center"> F
784 * <tr><th scope="row"> int <td style="text-align:center"> I
785 * <tr><th scope="row"> long <td style="text-align:center"> J
786 * <tr><th scope="row"> short <td style="text-align:center"> S
787 * </tbody>
788 * </table></blockquote>
789 *
790 * <p> The class or interface name <i>classname</i> is the binary name of
791 * the class specified above.
792 *
793 * <p> Examples:
794 * <blockquote><pre>
795 * String.class.getName()
796 * returns "java.lang.String"
797 * byte.class.getName()
798 * returns "byte"
799 * (new Object[3]).getClass().getName()
800 * returns "[Ljava.lang.Object;"
801 * (new int[3][4][5][6][7][8][9]).getClass().getName()
802 * returns "[[[[[[[I"
803 * </pre></blockquote>
804 *
805 * @return the name of the class or interface
806 * represented by this object.
807 */
808 public String getName() {
809 String name = this.name;
810 return name != null ? name : initClassName();
811 }
812
813 // Cache the name to reduce the number of calls into the VM.
814 // This field would be set by VM itself during initClassName call.
815 private transient String name;
816 private native String initClassName();
817
818 /**
819 * Returns the class loader for the class. Some implementations may use
820 * null to represent the bootstrap class loader. This method will return
821 * null in such implementations if this class was loaded by the bootstrap
822 * class loader.
823 *
824 * <p>If this object
825 * represents a primitive type or void, null is returned.
826 *
827 * @return the class loader that loaded the class or interface
828 * represented by this object.
829 * @throws SecurityException
830 * if a security manager is present, and the caller's class loader
831 * is not {@code null} and is not the same as or an ancestor of the
832 * class loader for the class whose class loader is requested,
833 * and the caller does not have the
834 * {@link RuntimePermission}{@code ("getClassLoader")}
835 * @see java.lang.ClassLoader
836 * @see SecurityManager#checkPermission
837 * @see java.lang.RuntimePermission
838 */
839 @CallerSensitive
840 @ForceInline // to ensure Reflection.getCallerClass optimization
841 public ClassLoader getClassLoader() {
842 ClassLoader cl = getClassLoader0();
843 if (cl == null)
844 return null;
845 SecurityManager sm = System.getSecurityManager();
846 if (sm != null) {
847 ClassLoader.checkClassLoaderPermission(cl, Reflection.getCallerClass());
848 }
849 return cl;
850 }
851
852 // Package-private to allow ClassLoader access
853 ClassLoader getClassLoader0() { return classLoader; }
854
855 /**
856 * Returns the module that this class or interface is a member of.
857 *
858 * If this class represents an array type then this method returns the
859 * {@code Module} for the element type. If this class represents a
860 * primitive type or void, then the {@code Module} object for the
861 * {@code java.base} module is returned.
862 *
863 * If this class is in an unnamed module then the {@linkplain
864 * ClassLoader#getUnnamedModule() unnamed} {@code Module} of the class
865 * loader for this class is returned.
866 *
867 * @return the module that this class or interface is a member of
868 *
869 * @since 9
870 * @spec JPMS
871 */
872 public Module getModule() {
873 return module;
874 }
875
876 // set by VM
877 private transient Module module;
878
879 // Initialized in JVM not by private constructor
880 // This field is filtered from reflection access, i.e. getDeclaredField
881 // will throw NoSuchFieldException
882 private final ClassLoader classLoader;
883
884 /**
885 * Returns an array of {@code TypeVariable} objects that represent the
886 * type variables declared by the generic declaration represented by this
887 * {@code GenericDeclaration} object, in declaration order. Returns an
888 * array of length 0 if the underlying generic declaration declares no type
889 * variables.
890 *
891 * @return an array of {@code TypeVariable} objects that represent
892 * the type variables declared by this generic declaration
893 * @throws java.lang.reflect.GenericSignatureFormatError if the generic
894 * signature of this generic declaration does not conform to
895 * the format specified in
896 * <cite>The Java™ Virtual Machine Specification</cite>
897 * @since 1.5
898 */
899 @SuppressWarnings("unchecked")
900 public TypeVariable<Class<T>>[] getTypeParameters() {
901 ClassRepository info = getGenericInfo();
902 if (info != null)
903 return (TypeVariable<Class<T>>[])info.getTypeParameters();
904 else
905 return (TypeVariable<Class<T>>[])new TypeVariable<?>[0];
906 }
907
908
909 /**
910 * Returns the {@code Class} representing the direct superclass of the
911 * entity (class, interface, primitive type or void) represented by
912 * this {@code Class}. If this {@code Class} represents either the
913 * {@code Object} class, an interface, a primitive type, or void, then
914 * null is returned. If this object represents an array class then the
915 * {@code Class} object representing the {@code Object} class is
916 * returned.
917 *
918 * @return the direct superclass of the class represented by this object
919 */
920 @HotSpotIntrinsicCandidate
921 public native Class<? super T> getSuperclass();
922
923
924 /**
925 * Returns the {@code Type} representing the direct superclass of
926 * the entity (class, interface, primitive type or void) represented by
927 * this {@code Class}.
928 *
929 * <p>If the superclass is a parameterized type, the {@code Type}
930 * object returned must accurately reflect the actual type
931 * arguments used in the source code. The parameterized type
932 * representing the superclass is created if it had not been
933 * created before. See the declaration of {@link
934 * java.lang.reflect.ParameterizedType ParameterizedType} for the
935 * semantics of the creation process for parameterized types. If
936 * this {@code Class} represents either the {@code Object}
937 * class, an interface, a primitive type, or void, then null is
938 * returned. If this object represents an array class then the
939 * {@code Class} object representing the {@code Object} class is
940 * returned.
941 *
942 * @throws java.lang.reflect.GenericSignatureFormatError if the generic
943 * class signature does not conform to the format specified in
944 * <cite>The Java™ Virtual Machine Specification</cite>
945 * @throws TypeNotPresentException if the generic superclass
946 * refers to a non-existent type declaration
947 * @throws java.lang.reflect.MalformedParameterizedTypeException if the
948 * generic superclass refers to a parameterized type that cannot be
949 * instantiated for any reason
950 * @return the direct superclass of the class represented by this object
951 * @since 1.5
952 */
953 public Type getGenericSuperclass() {
954 ClassRepository info = getGenericInfo();
955 if (info == null) {
956 return getSuperclass();
957 }
958
959 // Historical irregularity:
960 // Generic signature marks interfaces with superclass = Object
961 // but this API returns null for interfaces
962 if (isInterface()) {
963 return null;
964 }
965
966 return info.getSuperclass();
967 }
968
969 /**
970 * Gets the package of this class.
971 *
972 * <p>If this class represents an array type, a primitive type or void,
973 * this method returns {@code null}.
974 *
975 * @return the package of this class.
976 * @revised 9
977 * @spec JPMS
978 */
979 public Package getPackage() {
980 if (isPrimitive() || isArray()) {
981 return null;
982 }
983 ClassLoader cl = getClassLoader0();
984 return cl != null ? cl.definePackage(this)
985 : BootLoader.definePackage(this);
986 }
987
988 /**
989 * Returns the fully qualified package name.
990 *
991 * <p> If this class is a top level class, then this method returns the fully
992 * qualified name of the package that the class is a member of, or the
993 * empty string if the class is in an unnamed package.
994 *
995 * <p> If this class is a member class, then this method is equivalent to
996 * invoking {@code getPackageName()} on the {@linkplain #getEnclosingClass
997 * enclosing class}.
998 *
999 * <p> If this class is a {@linkplain #isLocalClass local class} or an {@linkplain
1000 * #isAnonymousClass() anonymous class}, then this method is equivalent to
1001 * invoking {@code getPackageName()} on the {@linkplain #getDeclaringClass
1002 * declaring class} of the {@linkplain #getEnclosingMethod enclosing method} or
1003 * {@linkplain #getEnclosingConstructor enclosing constructor}.
1004 *
1005 * <p> If this class represents an array type then this method returns the
1006 * package name of the element type. If this class represents a primitive
1007 * type or void then the package name "{@code java.lang}" is returned.
1008 *
1009 * @return the fully qualified package name
1010 *
1011 * @since 9
1012 * @spec JPMS
1013 * @jls 6.7 Fully Qualified Names
1014 */
1015 public String getPackageName() {
1016 String pn = this.packageName;
1017 if (pn == null) {
1018 Class<?> c = this;
1019 while (c.isArray()) {
1020 c = c.getComponentType();
1021 }
1022 if (c.isPrimitive()) {
1023 pn = "java.lang";
1024 } else {
1025 String cn = c.getName();
1026 int dot = cn.lastIndexOf('.');
1027 pn = (dot != -1) ? cn.substring(0, dot).intern() : "";
1028 }
1029 this.packageName = pn;
1030 }
1031 return pn;
1032 }
1033
1034 // cached package name
1035 private transient String packageName;
1036
1037 /**
1038 * Returns the interfaces directly implemented by the class or interface
1039 * represented by this object.
1040 *
1041 * <p>If this object represents a class, the return value is an array
1042 * containing objects representing all interfaces directly implemented by
1043 * the class. The order of the interface objects in the array corresponds
1044 * to the order of the interface names in the {@code implements} clause of
1045 * the declaration of the class represented by this object. For example,
1046 * given the declaration:
1047 * <blockquote>
1048 * {@code class Shimmer implements FloorWax, DessertTopping { ... }}
1049 * </blockquote>
1050 * suppose the value of {@code s} is an instance of
1051 * {@code Shimmer}; the value of the expression:
1052 * <blockquote>
1053 * {@code s.getClass().getInterfaces()[0]}
1054 * </blockquote>
1055 * is the {@code Class} object that represents interface
1056 * {@code FloorWax}; and the value of:
1057 * <blockquote>
1058 * {@code s.getClass().getInterfaces()[1]}
1059 * </blockquote>
1060 * is the {@code Class} object that represents interface
1061 * {@code DessertTopping}.
1062 *
1063 * <p>If this object represents an interface, the array contains objects
1064 * representing all interfaces directly extended by the interface. The
1065 * order of the interface objects in the array corresponds to the order of
1066 * the interface names in the {@code extends} clause of the declaration of
1067 * the interface represented by this object.
1068 *
1069 * <p>If this object represents a class or interface that implements no
1070 * interfaces, the method returns an array of length 0.
1071 *
1072 * <p>If this object represents a primitive type or void, the method
1073 * returns an array of length 0.
1074 *
1075 * <p>If this {@code Class} object represents an array type, the
1076 * interfaces {@code Cloneable} and {@code java.io.Serializable} are
1077 * returned in that order.
1078 *
1079 * @return an array of interfaces directly implemented by this class
1080 */
1081 public Class<?>[] getInterfaces() {
1082 // defensively copy before handing over to user code
1083 return getInterfaces(true);
1084 }
1085
1086 private Class<?>[] getInterfaces(boolean cloneArray) {
1087 ReflectionData<T> rd = reflectionData();
1088 if (rd == null) {
1089 // no cloning required
1090 return getInterfaces0();
1091 } else {
1092 Class<?>[] interfaces = rd.interfaces;
1093 if (interfaces == null) {
1094 interfaces = getInterfaces0();
1095 rd.interfaces = interfaces;
1096 }
1097 // defensively copy if requested
1098 return cloneArray ? interfaces.clone() : interfaces;
1099 }
1100 }
1101
1102 private native Class<?>[] getInterfaces0();
1103
1104 /**
1105 * Returns the {@code Type}s representing the interfaces
1106 * directly implemented by the class or interface represented by
1107 * this object.
1108 *
1109 * <p>If a superinterface is a parameterized type, the
1110 * {@code Type} object returned for it must accurately reflect
1111 * the actual type arguments used in the source code. The
1112 * parameterized type representing each superinterface is created
1113 * if it had not been created before. See the declaration of
1114 * {@link java.lang.reflect.ParameterizedType ParameterizedType}
1115 * for the semantics of the creation process for parameterized
1116 * types.
1117 *
1118 * <p>If this object represents a class, the return value is an array
1119 * containing objects representing all interfaces directly implemented by
1120 * the class. The order of the interface objects in the array corresponds
1121 * to the order of the interface names in the {@code implements} clause of
1122 * the declaration of the class represented by this object.
1123 *
1124 * <p>If this object represents an interface, the array contains objects
1125 * representing all interfaces directly extended by the interface. The
1126 * order of the interface objects in the array corresponds to the order of
1127 * the interface names in the {@code extends} clause of the declaration of
1128 * the interface represented by this object.
1129 *
1130 * <p>If this object represents a class or interface that implements no
1131 * interfaces, the method returns an array of length 0.
1132 *
1133 * <p>If this object represents a primitive type or void, the method
1134 * returns an array of length 0.
1135 *
1136 * <p>If this {@code Class} object represents an array type, the
1137 * interfaces {@code Cloneable} and {@code java.io.Serializable} are
1138 * returned in that order.
1139 *
1140 * @throws java.lang.reflect.GenericSignatureFormatError
1141 * if the generic class signature does not conform to the format
1142 * specified in
1143 * <cite>The Java™ Virtual Machine Specification</cite>
1144 * @throws TypeNotPresentException if any of the generic
1145 * superinterfaces refers to a non-existent type declaration
1146 * @throws java.lang.reflect.MalformedParameterizedTypeException
1147 * if any of the generic superinterfaces refer to a parameterized
1148 * type that cannot be instantiated for any reason
1149 * @return an array of interfaces directly implemented by this class
1150 * @since 1.5
1151 */
1152 public Type[] getGenericInterfaces() {
1153 ClassRepository info = getGenericInfo();
1154 return (info == null) ? getInterfaces() : info.getSuperInterfaces();
1155 }
1156
1157
1158 /**
1159 * Returns the {@code Class} representing the component type of an
1160 * array. If this class does not represent an array class this method
1161 * returns null.
1162 *
1163 * @return the {@code Class} representing the component type of this
1164 * class if this class is an array
1165 * @see java.lang.reflect.Array
1166 * @since 1.1
1167 */
1168 public Class<?> getComponentType() {
1169 // Only return for array types. Storage may be reused for Class for instance types.
1170 if (isArray()) {
1171 return componentType;
1172 } else {
1173 return null;
1174 }
1175 }
1176
1177 private final Class<?> componentType;
1178
1179
1180 /**
1181 * Returns the Java language modifiers for this class or interface, encoded
1182 * in an integer. The modifiers consist of the Java Virtual Machine's
1183 * constants for {@code public}, {@code protected},
1184 * {@code private}, {@code final}, {@code static},
1185 * {@code abstract} and {@code interface}; they should be decoded
1186 * using the methods of class {@code Modifier}.
1187 *
1188 * <p> If the underlying class is an array class, then its
1189 * {@code public}, {@code private} and {@code protected}
1190 * modifiers are the same as those of its component type. If this
1191 * {@code Class} represents a primitive type or void, its
1192 * {@code public} modifier is always {@code true}, and its
1193 * {@code protected} and {@code private} modifiers are always
1194 * {@code false}. If this object represents an array class, a
1195 * primitive type or void, then its {@code final} modifier is always
1196 * {@code true} and its interface modifier is always
1197 * {@code false}. The values of its other modifiers are not determined
1198 * by this specification.
1199 *
1200 * <p> The modifier encodings are defined in <em>The Java Virtual Machine
1201 * Specification</em>, table 4.1.
1202 *
1203 * @return the {@code int} representing the modifiers for this class
1204 * @see java.lang.reflect.Modifier
1205 * @since 1.1
1206 */
1207 @HotSpotIntrinsicCandidate
1208 public native int getModifiers();
1209
1210
1211 /**
1212 * Gets the signers of this class.
1213 *
1214 * @return the signers of this class, or null if there are no signers. In
1215 * particular, this method returns null if this object represents
1216 * a primitive type or void.
1217 * @since 1.1
1218 */
1219 public native Object[] getSigners();
1220
1221
1222 /**
1223 * Set the signers of this class.
1224 */
1225 native void setSigners(Object[] signers);
1226
1227
1228 /**
1229 * If this {@code Class} object represents a local or anonymous
1230 * class within a method, returns a {@link
1231 * java.lang.reflect.Method Method} object representing the
1232 * immediately enclosing method of the underlying class. Returns
1233 * {@code null} otherwise.
1234 *
1235 * In particular, this method returns {@code null} if the underlying
1236 * class is a local or anonymous class immediately enclosed by a type
1237 * declaration, instance initializer or static initializer.
1238 *
1239 * @return the immediately enclosing method of the underlying class, if
1240 * that class is a local or anonymous class; otherwise {@code null}.
1241 *
1242 * @throws SecurityException
1243 * If a security manager, <i>s</i>, is present and any of the
1244 * following conditions is met:
1245 *
1246 * <ul>
1247 *
1248 * <li> the caller's class loader is not the same as the
1249 * class loader of the enclosing class and invocation of
1250 * {@link SecurityManager#checkPermission
1251 * s.checkPermission} method with
1252 * {@code RuntimePermission("accessDeclaredMembers")}
1253 * denies access to the methods within the enclosing class
1254 *
1255 * <li> the caller's class loader is not the same as or an
1256 * ancestor of the class loader for the enclosing class and
1257 * invocation of {@link SecurityManager#checkPackageAccess
1258 * s.checkPackageAccess()} denies access to the package
1259 * of the enclosing class
1260 *
1261 * </ul>
1262 * @since 1.5
1263 */
1264 @CallerSensitive
1265 public Method getEnclosingMethod() throws SecurityException {
1266 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1267
1268 if (enclosingInfo == null)
1269 return null;
1270 else {
1271 if (!enclosingInfo.isMethod())
1272 return null;
1273
1274 MethodRepository typeInfo = MethodRepository.make(enclosingInfo.getDescriptor(),
1275 getFactory());
1276 Class<?> returnType = toClass(typeInfo.getReturnType());
1277 Type [] parameterTypes = typeInfo.getParameterTypes();
1278 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length];
1279
1280 // Convert Types to Classes; returned types *should*
1281 // be class objects since the methodDescriptor's used
1282 // don't have generics information
1283 for(int i = 0; i < parameterClasses.length; i++)
1284 parameterClasses[i] = toClass(parameterTypes[i]);
1285
1286 // Perform access check
1287 final Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass();
1288 SecurityManager sm = System.getSecurityManager();
1289 if (sm != null) {
1290 enclosingCandidate.checkMemberAccess(sm, Member.DECLARED,
1291 Reflection.getCallerClass(), true);
1292 }
1293 Method[] candidates = enclosingCandidate.privateGetDeclaredMethods(false);
1294
1295 /*
1296 * Loop over all declared methods; match method name,
1297 * number of and type of parameters, *and* return
1298 * type. Matching return type is also necessary
1299 * because of covariant returns, etc.
1300 */
1301 ReflectionFactory fact = getReflectionFactory();
1302 for (Method m : candidates) {
1303 if (m.getName().equals(enclosingInfo.getName()) &&
1304 arrayContentsEq(parameterClasses,
1305 fact.getExecutableSharedParameterTypes(m))) {
1306 // finally, check return type
1307 if (m.getReturnType().equals(returnType)) {
1308 return fact.copyMethod(m);
1309 }
1310 }
1311 }
1312
1313 throw new InternalError("Enclosing method not found");
1314 }
1315 }
1316
1317 private native Object[] getEnclosingMethod0();
1318
1319 private EnclosingMethodInfo getEnclosingMethodInfo() {
1320 Object[] enclosingInfo = getEnclosingMethod0();
1321 if (enclosingInfo == null)
1322 return null;
1323 else {
1324 return new EnclosingMethodInfo(enclosingInfo);
1325 }
1326 }
1327
1328 private static final class EnclosingMethodInfo {
1329 private final Class<?> enclosingClass;
1330 private final String name;
1331 private final String descriptor;
1332
1333 static void validate(Object[] enclosingInfo) {
1334 if (enclosingInfo.length != 3)
1335 throw new InternalError("Malformed enclosing method information");
1336 try {
1337 // The array is expected to have three elements:
1338
1339 // the immediately enclosing class
1340 Class<?> enclosingClass = (Class<?>)enclosingInfo[0];
1341 assert(enclosingClass != null);
1342
1343 // the immediately enclosing method or constructor's
1344 // name (can be null).
1345 String name = (String)enclosingInfo[1];
1346
1347 // the immediately enclosing method or constructor's
1348 // descriptor (null iff name is).
1349 String descriptor = (String)enclosingInfo[2];
1350 assert((name != null && descriptor != null) || name == descriptor);
1351 } catch (ClassCastException cce) {
1352 throw new InternalError("Invalid type in enclosing method information", cce);
1353 }
1354 }
1355
1356 EnclosingMethodInfo(Object[] enclosingInfo) {
1357 validate(enclosingInfo);
1358 this.enclosingClass = (Class<?>)enclosingInfo[0];
1359 this.name = (String)enclosingInfo[1];
1360 this.descriptor = (String)enclosingInfo[2];
1361 }
1362
1363 boolean isPartial() {
1364 return enclosingClass == null || name == null || descriptor == null;
1365 }
1366
1367 boolean isConstructor() { return !isPartial() && "<init>".equals(name); }
1368
1369 boolean isMethod() { return !isPartial() && !isConstructor() && !"<clinit>".equals(name); }
1370
1371 Class<?> getEnclosingClass() { return enclosingClass; }
1372
1373 String getName() { return name; }
1374
1375 String getDescriptor() { return descriptor; }
1376
1377 }
1378
1379 private static Class<?> toClass(Type o) {
1380 if (o instanceof GenericArrayType)
1381 return Array.newInstance(toClass(((GenericArrayType)o).getGenericComponentType()),
1382 0)
1383 .getClass();
1384 return (Class<?>)o;
1385 }
1386
1387 /**
1388 * If this {@code Class} object represents a local or anonymous
1389 * class within a constructor, returns a {@link
1390 * java.lang.reflect.Constructor Constructor} object representing
1391 * the immediately enclosing constructor of the underlying
1392 * class. Returns {@code null} otherwise. In particular, this
1393 * method returns {@code null} if the underlying class is a local
1394 * or anonymous class immediately enclosed by a type declaration,
1395 * instance initializer or static initializer.
1396 *
1397 * @return the immediately enclosing constructor of the underlying class, if
1398 * that class is a local or anonymous class; otherwise {@code null}.
1399 * @throws SecurityException
1400 * If a security manager, <i>s</i>, is present and any of the
1401 * following conditions is met:
1402 *
1403 * <ul>
1404 *
1405 * <li> the caller's class loader is not the same as the
1406 * class loader of the enclosing class and invocation of
1407 * {@link SecurityManager#checkPermission
1408 * s.checkPermission} method with
1409 * {@code RuntimePermission("accessDeclaredMembers")}
1410 * denies access to the constructors within the enclosing class
1411 *
1412 * <li> the caller's class loader is not the same as or an
1413 * ancestor of the class loader for the enclosing class and
1414 * invocation of {@link SecurityManager#checkPackageAccess
1415 * s.checkPackageAccess()} denies access to the package
1416 * of the enclosing class
1417 *
1418 * </ul>
1419 * @since 1.5
1420 */
1421 @CallerSensitive
1422 public Constructor<?> getEnclosingConstructor() throws SecurityException {
1423 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1424
1425 if (enclosingInfo == null)
1426 return null;
1427 else {
1428 if (!enclosingInfo.isConstructor())
1429 return null;
1430
1431 ConstructorRepository typeInfo = ConstructorRepository.make(enclosingInfo.getDescriptor(),
1432 getFactory());
1433 Type [] parameterTypes = typeInfo.getParameterTypes();
1434 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length];
1435
1436 // Convert Types to Classes; returned types *should*
1437 // be class objects since the methodDescriptor's used
1438 // don't have generics information
1439 for(int i = 0; i < parameterClasses.length; i++)
1440 parameterClasses[i] = toClass(parameterTypes[i]);
1441
1442 // Perform access check
1443 final Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass();
1444 SecurityManager sm = System.getSecurityManager();
1445 if (sm != null) {
1446 enclosingCandidate.checkMemberAccess(sm, Member.DECLARED,
1447 Reflection.getCallerClass(), true);
1448 }
1449
1450 Constructor<?>[] candidates = enclosingCandidate
1451 .privateGetDeclaredConstructors(false);
1452 /*
1453 * Loop over all declared constructors; match number
1454 * of and type of parameters.
1455 */
1456 ReflectionFactory fact = getReflectionFactory();
1457 for (Constructor<?> c : candidates) {
1458 if (arrayContentsEq(parameterClasses,
1459 fact.getExecutableSharedParameterTypes(c))) {
1460 return fact.copyConstructor(c);
1461 }
1462 }
1463
1464 throw new InternalError("Enclosing constructor not found");
1465 }
1466 }
1467
1468
1469 /**
1470 * If the class or interface represented by this {@code Class} object
1471 * is a member of another class, returns the {@code Class} object
1472 * representing the class in which it was declared. This method returns
1473 * null if this class or interface is not a member of any other class. If
1474 * this {@code Class} object represents an array class, a primitive
1475 * type, or void,then this method returns null.
1476 *
1477 * @return the declaring class for this class
1478 * @throws SecurityException
1479 * If a security manager, <i>s</i>, is present and the caller's
1480 * class loader is not the same as or an ancestor of the class
1481 * loader for the declaring class and invocation of {@link
1482 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
1483 * denies access to the package of the declaring class
1484 * @since 1.1
1485 */
1486 @CallerSensitive
1487 public Class<?> getDeclaringClass() throws SecurityException {
1488 final Class<?> candidate = getDeclaringClass0();
1489
1490 if (candidate != null) {
1491 SecurityManager sm = System.getSecurityManager();
1492 if (sm != null) {
1493 candidate.checkPackageAccess(sm,
1494 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
1495 }
1496 }
1497 return candidate;
1498 }
1499
1500 private native Class<?> getDeclaringClass0();
1501
1502
1503 /**
1504 * Returns the immediately enclosing class of the underlying
1505 * class. If the underlying class is a top level class this
1506 * method returns {@code null}.
1507 * @return the immediately enclosing class of the underlying class
1508 * @throws SecurityException
1509 * If a security manager, <i>s</i>, is present and the caller's
1510 * class loader is not the same as or an ancestor of the class
1511 * loader for the enclosing class and invocation of {@link
1512 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
1513 * denies access to the package of the enclosing class
1514 * @since 1.5
1515 */
1516 @CallerSensitive
1517 public Class<?> getEnclosingClass() throws SecurityException {
1518 // There are five kinds of classes (or interfaces):
1519 // a) Top level classes
1520 // b) Nested classes (static member classes)
1521 // c) Inner classes (non-static member classes)
1522 // d) Local classes (named classes declared within a method)
1523 // e) Anonymous classes
1524
1525
1526 // JVM Spec 4.7.7: A class must have an EnclosingMethod
1527 // attribute if and only if it is a local class or an
1528 // anonymous class.
1529 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1530 Class<?> enclosingCandidate;
1531
1532 if (enclosingInfo == null) {
1533 // This is a top level or a nested class or an inner class (a, b, or c)
1534 enclosingCandidate = getDeclaringClass0();
1535 } else {
1536 Class<?> enclosingClass = enclosingInfo.getEnclosingClass();
1537 // This is a local class or an anonymous class (d or e)
1538 if (enclosingClass == this || enclosingClass == null)
1539 throw new InternalError("Malformed enclosing method information");
1540 else
1541 enclosingCandidate = enclosingClass;
1542 }
1543
1544 if (enclosingCandidate != null) {
1545 SecurityManager sm = System.getSecurityManager();
1546 if (sm != null) {
1547 enclosingCandidate.checkPackageAccess(sm,
1548 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
1549 }
1550 }
1551 return enclosingCandidate;
1552 }
1553
1554 /**
1555 * Returns the simple name of the underlying class as given in the
1556 * source code. Returns an empty string if the underlying class is
1557 * anonymous.
1558 *
1559 * <p>The simple name of an array is the simple name of the
1560 * component type with "[]" appended. In particular the simple
1561 * name of an array whose component type is anonymous is "[]".
1562 *
1563 * @return the simple name of the underlying class
1564 * @since 1.5
1565 */
1566 public String getSimpleName() {
1567 ReflectionData<T> rd = reflectionData();
1568 String simpleName = rd.simpleName;
1569 if (simpleName == null) {
1570 rd.simpleName = simpleName = getSimpleName0();
1571 }
1572 return simpleName;
1573 }
1574
1575 private String getSimpleName0() {
1576 if (isArray()) {
1577 return getComponentType().getSimpleName() + "[]";
1578 }
1579 String simpleName = getSimpleBinaryName();
1580 if (simpleName == null) { // top level class
1581 simpleName = getName();
1582 simpleName = simpleName.substring(simpleName.lastIndexOf('.') + 1); // strip the package name
1583 }
1584 return simpleName;
1585 }
1586
1587 /**
1588 * Return an informative string for the name of this type.
1589 *
1590 * @return an informative string for the name of this type
1591 * @since 1.8
1592 */
1593 public String getTypeName() {
1594 if (isArray()) {
1595 try {
1596 Class<?> cl = this;
1597 int dimensions = 0;
1598 do {
1599 dimensions++;
1600 cl = cl.getComponentType();
1601 } while (cl.isArray());
1602 return cl.getName() + "[]".repeat(dimensions);
1603 } catch (Throwable e) { /*FALLTHRU*/ }
1604 }
1605 return getName();
1606 }
1607
1608 /**
1609 * Returns the canonical name of the underlying class as
1610 * defined by the Java Language Specification. Returns null if
1611 * the underlying class does not have a canonical name (i.e., if
1612 * it is a local or anonymous class or an array whose component
1613 * type does not have a canonical name).
1614 * @return the canonical name of the underlying class if it exists, and
1615 * {@code null} otherwise.
1616 * @since 1.5
1617 */
1618 public String getCanonicalName() {
1619 ReflectionData<T> rd = reflectionData();
1620 String canonicalName = rd.canonicalName;
1621 if (canonicalName == null) {
1622 rd.canonicalName = canonicalName = getCanonicalName0();
1623 }
1624 return canonicalName == ReflectionData.NULL_SENTINEL? null : canonicalName;
1625 }
1626
1627 private String getCanonicalName0() {
1628 if (isArray()) {
1629 String canonicalName = getComponentType().getCanonicalName();
1630 if (canonicalName != null)
1631 return canonicalName + "[]";
1632 else
1633 return ReflectionData.NULL_SENTINEL;
1634 }
1635 if (isLocalOrAnonymousClass())
1636 return ReflectionData.NULL_SENTINEL;
1637 Class<?> enclosingClass = getEnclosingClass();
1638 if (enclosingClass == null) { // top level class
1639 return getName();
1640 } else {
1641 String enclosingName = enclosingClass.getCanonicalName();
1642 if (enclosingName == null)
1643 return ReflectionData.NULL_SENTINEL;
1644 return enclosingName + "." + getSimpleName();
1645 }
1646 }
1647
1648 /**
1649 * Returns {@code true} if and only if the underlying class
1650 * is an anonymous class.
1651 *
1652 * @return {@code true} if and only if this class is an anonymous class.
1653 * @since 1.5
1654 */
1655 public boolean isAnonymousClass() {
1656 return !isArray() && isLocalOrAnonymousClass() &&
1657 getSimpleBinaryName0() == null;
1658 }
1659
1660 /**
1661 * Returns {@code true} if and only if the underlying class
1662 * is a local class.
1663 *
1664 * @return {@code true} if and only if this class is a local class.
1665 * @since 1.5
1666 */
1667 public boolean isLocalClass() {
1668 return isLocalOrAnonymousClass() &&
1669 (isArray() || getSimpleBinaryName0() != null);
1670 }
1671
1672 /**
1673 * Returns {@code true} if and only if the underlying class
1674 * is a member class.
1675 *
1676 * @return {@code true} if and only if this class is a member class.
1677 * @since 1.5
1678 */
1679 public boolean isMemberClass() {
1680 return !isLocalOrAnonymousClass() && getDeclaringClass0() != null;
1681 }
1682
1683 /**
1684 * Returns the "simple binary name" of the underlying class, i.e.,
1685 * the binary name without the leading enclosing class name.
1686 * Returns {@code null} if the underlying class is a top level
1687 * class.
1688 */
1689 private String getSimpleBinaryName() {
1690 if (isTopLevelClass())
1691 return null;
1692 String name = getSimpleBinaryName0();
1693 if (name == null) // anonymous class
1694 return "";
1695 return name;
1696 }
1697
1698 private native String getSimpleBinaryName0();
1699
1700 /**
1701 * Returns {@code true} if this is a top level class. Returns {@code false}
1702 * otherwise.
1703 */
1704 private boolean isTopLevelClass() {
1705 return !isLocalOrAnonymousClass() && getDeclaringClass0() == null;
1706 }
1707
1708 /**
1709 * Returns {@code true} if this is a local class or an anonymous
1710 * class. Returns {@code false} otherwise.
1711 */
1712 private boolean isLocalOrAnonymousClass() {
1713 // JVM Spec 4.7.7: A class must have an EnclosingMethod
1714 // attribute if and only if it is a local class or an
1715 // anonymous class.
1716 return hasEnclosingMethodInfo();
1717 }
1718
1719 private boolean hasEnclosingMethodInfo() {
1720 Object[] enclosingInfo = getEnclosingMethod0();
1721 if (enclosingInfo != null) {
1722 EnclosingMethodInfo.validate(enclosingInfo);
1723 return true;
1724 }
1725 return false;
1726 }
1727
1728 /**
1729 * Returns an array containing {@code Class} objects representing all
1730 * the public classes and interfaces that are members of the class
1731 * represented by this {@code Class} object. This includes public
1732 * class and interface members inherited from superclasses and public class
1733 * and interface members declared by the class. This method returns an
1734 * array of length 0 if this {@code Class} object has no public member
1735 * classes or interfaces. This method also returns an array of length 0 if
1736 * this {@code Class} object represents a primitive type, an array
1737 * class, or void.
1738 *
1739 * @return the array of {@code Class} objects representing the public
1740 * members of this class
1741 * @throws SecurityException
1742 * If a security manager, <i>s</i>, is present and
1743 * the caller's class loader is not the same as or an
1744 * ancestor of the class loader for the current class and
1745 * invocation of {@link SecurityManager#checkPackageAccess
1746 * s.checkPackageAccess()} denies access to the package
1747 * of this class.
1748 *
1749 * @since 1.1
1750 */
1751 @CallerSensitive
1752 public Class<?>[] getClasses() {
1753 SecurityManager sm = System.getSecurityManager();
1754 if (sm != null) {
1755 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), false);
1756 }
1757
1758 // Privileged so this implementation can look at DECLARED classes,
1759 // something the caller might not have privilege to do. The code here
1760 // is allowed to look at DECLARED classes because (1) it does not hand
1761 // out anything other than public members and (2) public member access
1762 // has already been ok'd by the SecurityManager.
1763
1764 return java.security.AccessController.doPrivileged(
1765 new java.security.PrivilegedAction<>() {
1766 public Class<?>[] run() {
1767 List<Class<?>> list = new ArrayList<>();
1768 Class<?> currentClass = Class.this;
1769 while (currentClass != null) {
1770 for (Class<?> m : currentClass.getDeclaredClasses()) {
1771 if (Modifier.isPublic(m.getModifiers())) {
1772 list.add(m);
1773 }
1774 }
1775 currentClass = currentClass.getSuperclass();
1776 }
1777 return list.toArray(new Class<?>[0]);
1778 }
1779 });
1780 }
1781
1782
1783 /**
1784 * Returns an array containing {@code Field} objects reflecting all
1785 * the accessible public fields of the class or interface represented by
1786 * this {@code Class} object.
1787 *
1788 * <p> If this {@code Class} object represents a class or interface with
1789 * no accessible public fields, then this method returns an array of length
1790 * 0.
1791 *
1792 * <p> If this {@code Class} object represents a class, then this method
1793 * returns the public fields of the class and of all its superclasses and
1794 * superinterfaces.
1795 *
1796 * <p> If this {@code Class} object represents an interface, then this
1797 * method returns the fields of the interface and of all its
1798 * superinterfaces.
1799 *
1800 * <p> If this {@code Class} object represents an array type, a primitive
1801 * type, or void, then this method returns an array of length 0.
1802 *
1803 * <p> The elements in the returned array are not sorted and are not in any
1804 * particular order.
1805 *
1806 * @return the array of {@code Field} objects representing the
1807 * public fields
1808 * @throws SecurityException
1809 * If a security manager, <i>s</i>, is present and
1810 * the caller's class loader is not the same as or an
1811 * ancestor of the class loader for the current class and
1812 * invocation of {@link SecurityManager#checkPackageAccess
1813 * s.checkPackageAccess()} denies access to the package
1814 * of this class.
1815 *
1816 * @since 1.1
1817 * @jls 8.2 Class Members
1818 * @jls 8.3 Field Declarations
1819 */
1820 @CallerSensitive
1821 public Field[] getFields() throws SecurityException {
1822 SecurityManager sm = System.getSecurityManager();
1823 if (sm != null) {
1824 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
1825 }
1826 return copyFields(privateGetPublicFields());
1827 }
1828
1829
1830 /**
1831 * Returns an array containing {@code Method} objects reflecting all the
1832 * public methods of the class or interface represented by this {@code
1833 * Class} object, including those declared by the class or interface and
1834 * those inherited from superclasses and superinterfaces.
1835 *
1836 * <p> If this {@code Class} object represents an array type, then the
1837 * returned array has a {@code Method} object for each of the public
1838 * methods inherited by the array type from {@code Object}. It does not
1839 * contain a {@code Method} object for {@code clone()}.
1840 *
1841 * <p> If this {@code Class} object represents an interface then the
1842 * returned array does not contain any implicitly declared methods from
1843 * {@code Object}. Therefore, if no methods are explicitly declared in
1844 * this interface or any of its superinterfaces then the returned array
1845 * has length 0. (Note that a {@code Class} object which represents a class
1846 * always has public methods, inherited from {@code Object}.)
1847 *
1848 * <p> The returned array never contains methods with names "{@code <init>}"
1849 * or "{@code <clinit>}".
1850 *
1851 * <p> The elements in the returned array are not sorted and are not in any
1852 * particular order.
1853 *
1854 * <p> Generally, the result is computed as with the following 4 step algorithm.
1855 * Let C be the class or interface represented by this {@code Class} object:
1856 * <ol>
1857 * <li> A union of methods is composed of:
1858 * <ol type="a">
1859 * <li> C's declared public instance and static methods as returned by
1860 * {@link #getDeclaredMethods()} and filtered to include only public
1861 * methods.</li>
1862 * <li> If C is a class other than {@code Object}, then include the result
1863 * of invoking this algorithm recursively on the superclass of C.</li>
1864 * <li> Include the results of invoking this algorithm recursively on all
1865 * direct superinterfaces of C, but include only instance methods.</li>
1866 * </ol></li>
1867 * <li> Union from step 1 is partitioned into subsets of methods with same
1868 * signature (name, parameter types) and return type.</li>
1869 * <li> Within each such subset only the most specific methods are selected.
1870 * Let method M be a method from a set of methods with same signature
1871 * and return type. M is most specific if there is no such method
1872 * N != M from the same set, such that N is more specific than M.
1873 * N is more specific than M if:
1874 * <ol type="a">
1875 * <li> N is declared by a class and M is declared by an interface; or</li>
1876 * <li> N and M are both declared by classes or both by interfaces and
1877 * N's declaring type is the same as or a subtype of M's declaring type
1878 * (clearly, if M's and N's declaring types are the same type, then
1879 * M and N are the same method).</li>
1880 * </ol></li>
1881 * <li> The result of this algorithm is the union of all selected methods from
1882 * step 3.</li>
1883 * </ol>
1884 *
1885 * @apiNote There may be more than one method with a particular name
1886 * and parameter types in a class because while the Java language forbids a
1887 * class to declare multiple methods with the same signature but different
1888 * return types, the Java virtual machine does not. This
1889 * increased flexibility in the virtual machine can be used to
1890 * implement various language features. For example, covariant
1891 * returns can be implemented with {@linkplain
1892 * java.lang.reflect.Method#isBridge bridge methods}; the bridge
1893 * method and the overriding method would have the same
1894 * signature but different return types.
1895 *
1896 * @return the array of {@code Method} objects representing the
1897 * public methods of this class
1898 * @throws SecurityException
1899 * If a security manager, <i>s</i>, is present and
1900 * the caller's class loader is not the same as or an
1901 * ancestor of the class loader for the current class and
1902 * invocation of {@link SecurityManager#checkPackageAccess
1903 * s.checkPackageAccess()} denies access to the package
1904 * of this class.
1905 *
1906 * @jls 8.2 Class Members
1907 * @jls 8.4 Method Declarations
1908 * @since 1.1
1909 */
1910 @CallerSensitive
1911 public Method[] getMethods() throws SecurityException {
1912 SecurityManager sm = System.getSecurityManager();
1913 if (sm != null) {
1914 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
1915 }
1916 return copyMethods(privateGetPublicMethods());
1917 }
1918
1919
1920 /**
1921 * Returns an array containing {@code Constructor} objects reflecting
1922 * all the public constructors of the class represented by this
1923 * {@code Class} object. An array of length 0 is returned if the
1924 * class has no public constructors, or if the class is an array class, or
1925 * if the class reflects a primitive type or void.
1926 *
1927 * Note that while this method returns an array of {@code
1928 * Constructor<T>} objects (that is an array of constructors from
1929 * this class), the return type of this method is {@code
1930 * Constructor<?>[]} and <em>not</em> {@code Constructor<T>[]} as
1931 * might be expected. This less informative return type is
1932 * necessary since after being returned from this method, the
1933 * array could be modified to hold {@code Constructor} objects for
1934 * different classes, which would violate the type guarantees of
1935 * {@code Constructor<T>[]}.
1936 *
1937 * @return the array of {@code Constructor} objects representing the
1938 * public constructors of this class
1939 * @throws SecurityException
1940 * If a security manager, <i>s</i>, is present and
1941 * the caller's class loader is not the same as or an
1942 * ancestor of the class loader for the current class and
1943 * invocation of {@link SecurityManager#checkPackageAccess
1944 * s.checkPackageAccess()} denies access to the package
1945 * of this class.
1946 *
1947 * @since 1.1
1948 */
1949 @CallerSensitive
1950 public Constructor<?>[] getConstructors() throws SecurityException {
1951 SecurityManager sm = System.getSecurityManager();
1952 if (sm != null) {
1953 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
1954 }
1955 return copyConstructors(privateGetDeclaredConstructors(true));
1956 }
1957
1958
1959 /**
1960 * Returns a {@code Field} object that reflects the specified public member
1961 * field of the class or interface represented by this {@code Class}
1962 * object. The {@code name} parameter is a {@code String} specifying the
1963 * simple name of the desired field.
1964 *
1965 * <p> The field to be reflected is determined by the algorithm that
1966 * follows. Let C be the class or interface represented by this object:
1967 *
1968 * <OL>
1969 * <LI> If C declares a public field with the name specified, that is the
1970 * field to be reflected.</LI>
1971 * <LI> If no field was found in step 1 above, this algorithm is applied
1972 * recursively to each direct superinterface of C. The direct
1973 * superinterfaces are searched in the order they were declared.</LI>
1974 * <LI> If no field was found in steps 1 and 2 above, and C has a
1975 * superclass S, then this algorithm is invoked recursively upon S.
1976 * If C has no superclass, then a {@code NoSuchFieldException}
1977 * is thrown.</LI>
1978 * </OL>
1979 *
1980 * <p> If this {@code Class} object represents an array type, then this
1981 * method does not find the {@code length} field of the array type.
1982 *
1983 * @param name the field name
1984 * @return the {@code Field} object of this class specified by
1985 * {@code name}
1986 * @throws NoSuchFieldException if a field with the specified name is
1987 * not found.
1988 * @throws NullPointerException if {@code name} is {@code null}
1989 * @throws SecurityException
1990 * If a security manager, <i>s</i>, is present and
1991 * the caller's class loader is not the same as or an
1992 * ancestor of the class loader for the current class and
1993 * invocation of {@link SecurityManager#checkPackageAccess
1994 * s.checkPackageAccess()} denies access to the package
1995 * of this class.
1996 *
1997 * @since 1.1
1998 * @jls 8.2 Class Members
1999 * @jls 8.3 Field Declarations
2000 */
2001 @CallerSensitive
2002 public Field getField(String name)
2003 throws NoSuchFieldException, SecurityException {
2004 Objects.requireNonNull(name);
2005 SecurityManager sm = System.getSecurityManager();
2006 if (sm != null) {
2007 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2008 }
2009 Field field = getField0(name);
2010 if (field == null) {
2011 throw new NoSuchFieldException(name);
2012 }
2013 return getReflectionFactory().copyField(field);
2014 }
2015
2016
2017 /**
2018 * Returns a {@code Method} object that reflects the specified public
2019 * member method of the class or interface represented by this
2020 * {@code Class} object. The {@code name} parameter is a
2021 * {@code String} specifying the simple name of the desired method. The
2022 * {@code parameterTypes} parameter is an array of {@code Class}
2023 * objects that identify the method's formal parameter types, in declared
2024 * order. If {@code parameterTypes} is {@code null}, it is
2025 * treated as if it were an empty array.
2026 *
2027 * <p> If this {@code Class} object represents an array type, then this
2028 * method finds any public method inherited by the array type from
2029 * {@code Object} except method {@code clone()}.
2030 *
2031 * <p> If this {@code Class} object represents an interface then this
2032 * method does not find any implicitly declared method from
2033 * {@code Object}. Therefore, if no methods are explicitly declared in
2034 * this interface or any of its superinterfaces, then this method does not
2035 * find any method.
2036 *
2037 * <p> This method does not find any method with name "{@code <init>}" or
2038 * "{@code <clinit>}".
2039 *
2040 * <p> Generally, the method to be reflected is determined by the 4 step
2041 * algorithm that follows.
2042 * Let C be the class or interface represented by this {@code Class} object:
2043 * <ol>
2044 * <li> A union of methods is composed of:
2045 * <ol type="a">
2046 * <li> C's declared public instance and static methods as returned by
2047 * {@link #getDeclaredMethods()} and filtered to include only public
2048 * methods that match given {@code name} and {@code parameterTypes}</li>
2049 * <li> If C is a class other than {@code Object}, then include the result
2050 * of invoking this algorithm recursively on the superclass of C.</li>
2051 * <li> Include the results of invoking this algorithm recursively on all
2052 * direct superinterfaces of C, but include only instance methods.</li>
2053 * </ol></li>
2054 * <li> This union is partitioned into subsets of methods with same
2055 * return type (the selection of methods from step 1 also guarantees that
2056 * they have the same method name and parameter types).</li>
2057 * <li> Within each such subset only the most specific methods are selected.
2058 * Let method M be a method from a set of methods with same VM
2059 * signature (return type, name, parameter types).
2060 * M is most specific if there is no such method N != M from the same
2061 * set, such that N is more specific than M. N is more specific than M
2062 * if:
2063 * <ol type="a">
2064 * <li> N is declared by a class and M is declared by an interface; or</li>
2065 * <li> N and M are both declared by classes or both by interfaces and
2066 * N's declaring type is the same as or a subtype of M's declaring type
2067 * (clearly, if M's and N's declaring types are the same type, then
2068 * M and N are the same method).</li>
2069 * </ol></li>
2070 * <li> The result of this algorithm is chosen arbitrarily from the methods
2071 * with most specific return type among all selected methods from step 3.
2072 * Let R be a return type of a method M from the set of all selected methods
2073 * from step 3. M is a method with most specific return type if there is
2074 * no such method N != M from the same set, having return type S != R,
2075 * such that S is a subtype of R as determined by
2076 * R.class.{@link #isAssignableFrom}(S.class).
2077 * </ol>
2078 *
2079 * @apiNote There may be more than one method with matching name and
2080 * parameter types in a class because while the Java language forbids a
2081 * class to declare multiple methods with the same signature but different
2082 * return types, the Java virtual machine does not. This
2083 * increased flexibility in the virtual machine can be used to
2084 * implement various language features. For example, covariant
2085 * returns can be implemented with {@linkplain
2086 * java.lang.reflect.Method#isBridge bridge methods}; the bridge
2087 * method and the overriding method would have the same
2088 * signature but different return types. This method would return the
2089 * overriding method as it would have a more specific return type.
2090 *
2091 * @param name the name of the method
2092 * @param parameterTypes the list of parameters
2093 * @return the {@code Method} object that matches the specified
2094 * {@code name} and {@code parameterTypes}
2095 * @throws NoSuchMethodException if a matching method is not found
2096 * or if the name is "<init>"or "<clinit>".
2097 * @throws NullPointerException if {@code name} is {@code null}
2098 * @throws SecurityException
2099 * If a security manager, <i>s</i>, is present and
2100 * the caller's class loader is not the same as or an
2101 * ancestor of the class loader for the current class and
2102 * invocation of {@link SecurityManager#checkPackageAccess
2103 * s.checkPackageAccess()} denies access to the package
2104 * of this class.
2105 *
2106 * @jls 8.2 Class Members
2107 * @jls 8.4 Method Declarations
2108 * @since 1.1
2109 */
2110 @CallerSensitive
2111 public Method getMethod(String name, Class<?>... parameterTypes)
2112 throws NoSuchMethodException, SecurityException {
2113 Objects.requireNonNull(name);
2114 SecurityManager sm = System.getSecurityManager();
2115 if (sm != null) {
2116 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2117 }
2118 Method method = getMethod0(name, parameterTypes);
2119 if (method == null) {
2120 throw new NoSuchMethodException(methodToString(name, parameterTypes));
2121 }
2122 return getReflectionFactory().copyMethod(method);
2123 }
2124
2125 /**
2126 * Returns a {@code Constructor} object that reflects the specified
2127 * public constructor of the class represented by this {@code Class}
2128 * object. The {@code parameterTypes} parameter is an array of
2129 * {@code Class} objects that identify the constructor's formal
2130 * parameter types, in declared order.
2131 *
2132 * If this {@code Class} object represents an inner class
2133 * declared in a non-static context, the formal parameter types
2134 * include the explicit enclosing instance as the first parameter.
2135 *
2136 * <p> The constructor to reflect is the public constructor of the class
2137 * represented by this {@code Class} object whose formal parameter
2138 * types match those specified by {@code parameterTypes}.
2139 *
2140 * @param parameterTypes the parameter array
2141 * @return the {@code Constructor} object of the public constructor that
2142 * matches the specified {@code parameterTypes}
2143 * @throws NoSuchMethodException if a matching method is not found.
2144 * @throws SecurityException
2145 * If a security manager, <i>s</i>, is present and
2146 * the caller's class loader is not the same as or an
2147 * ancestor of the class loader for the current class and
2148 * invocation of {@link SecurityManager#checkPackageAccess
2149 * s.checkPackageAccess()} denies access to the package
2150 * of this class.
2151 *
2152 * @since 1.1
2153 */
2154 @CallerSensitive
2155 public Constructor<T> getConstructor(Class<?>... parameterTypes)
2156 throws NoSuchMethodException, SecurityException
2157 {
2158 SecurityManager sm = System.getSecurityManager();
2159 if (sm != null) {
2160 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2161 }
2162 return getReflectionFactory().copyConstructor(
2163 getConstructor0(parameterTypes, Member.PUBLIC));
2164 }
2165
2166
2167 /**
2168 * Returns an array of {@code Class} objects reflecting all the
2169 * classes and interfaces declared as members of the class represented by
2170 * this {@code Class} object. This includes public, protected, default
2171 * (package) access, and private classes and interfaces declared by the
2172 * class, but excludes inherited classes and interfaces. This method
2173 * returns an array of length 0 if the class declares no classes or
2174 * interfaces as members, or if this {@code Class} object represents a
2175 * primitive type, an array class, or void.
2176 *
2177 * @return the array of {@code Class} objects representing all the
2178 * declared members of this class
2179 * @throws SecurityException
2180 * If a security manager, <i>s</i>, is present and any of the
2181 * following conditions is met:
2182 *
2183 * <ul>
2184 *
2185 * <li> the caller's class loader is not the same as the
2186 * class loader of this class and invocation of
2187 * {@link SecurityManager#checkPermission
2188 * s.checkPermission} method with
2189 * {@code RuntimePermission("accessDeclaredMembers")}
2190 * denies access to the declared classes within this class
2191 *
2192 * <li> the caller's class loader is not the same as or an
2193 * ancestor of the class loader for the current class and
2194 * invocation of {@link SecurityManager#checkPackageAccess
2195 * s.checkPackageAccess()} denies access to the package
2196 * of this class
2197 *
2198 * </ul>
2199 *
2200 * @since 1.1
2201 */
2202 @CallerSensitive
2203 public Class<?>[] getDeclaredClasses() throws SecurityException {
2204 SecurityManager sm = System.getSecurityManager();
2205 if (sm != null) {
2206 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), false);
2207 }
2208 return getDeclaredClasses0();
2209 }
2210
2211
2212 /**
2213 * Returns an array of {@code Field} objects reflecting all the fields
2214 * declared by the class or interface represented by this
2215 * {@code Class} object. This includes public, protected, default
2216 * (package) access, and private fields, but excludes inherited fields.
2217 *
2218 * <p> If this {@code Class} object represents a class or interface with no
2219 * declared fields, then this method returns an array of length 0.
2220 *
2221 * <p> If this {@code Class} object represents an array type, a primitive
2222 * type, or void, then this method returns an array of length 0.
2223 *
2224 * <p> The elements in the returned array are not sorted and are not in any
2225 * particular order.
2226 *
2227 * @return the array of {@code Field} objects representing all the
2228 * declared fields of this class
2229 * @throws SecurityException
2230 * If a security manager, <i>s</i>, is present and any of the
2231 * following conditions is met:
2232 *
2233 * <ul>
2234 *
2235 * <li> the caller's class loader is not the same as the
2236 * class loader of this class and invocation of
2237 * {@link SecurityManager#checkPermission
2238 * s.checkPermission} method with
2239 * {@code RuntimePermission("accessDeclaredMembers")}
2240 * denies access to the declared fields within this class
2241 *
2242 * <li> the caller's class loader is not the same as or an
2243 * ancestor of the class loader for the current class and
2244 * invocation of {@link SecurityManager#checkPackageAccess
2245 * s.checkPackageAccess()} denies access to the package
2246 * of this class
2247 *
2248 * </ul>
2249 *
2250 * @since 1.1
2251 * @jls 8.2 Class Members
2252 * @jls 8.3 Field Declarations
2253 */
2254 @CallerSensitive
2255 public Field[] getDeclaredFields() throws SecurityException {
2256 SecurityManager sm = System.getSecurityManager();
2257 if (sm != null) {
2258 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2259 }
2260 return copyFields(privateGetDeclaredFields(false));
2261 }
2262
2263 /**
2264 * {@preview Associated with records, a preview feature of the Java language.
2265 *
2266 * This method is associated with <i>records</i>, a preview
2267 * feature of the Java language. Preview features
2268 * may be removed in a future release, or upgraded to permanent
2269 * features of the Java language.}
2270 *
2271 * Returns an array containing {@code RecordComponent} objects reflecting all the
2272 * declared record components of the record represented by this {@code Class} object.
2273 * The components are returned in the same order that they are declared in the
2274 * record header.
2275 *
2276 * @return The array of {@code RecordComponent} objects representing all the
2277 * record components of this record. The array is empty if this class
2278 * is not a record, or if this class is a record with no components.
2279 * @throws SecurityException
2280 * If a security manager, <i>s</i>, is present and any of the
2281 * following conditions is met:
2282 *
2283 * <ul>
2284 *
2285 * <li> the caller's class loader is not the same as the
2286 * class loader of this class and invocation of
2287 * {@link SecurityManager#checkPermission
2288 * s.checkPermission} method with
2289 * {@code RuntimePermission("accessDeclaredMembers")}
2290 * denies access to the declared methods within this class
2291 *
2292 * <li> the caller's class loader is not the same as or an
2293 * ancestor of the class loader for the current class and
2294 * invocation of {@link SecurityManager#checkPackageAccess
2295 * s.checkPackageAccess()} denies access to the package
2296 * of this class
2297 *
2298 * </ul>
2299 *
2300 * @jls 8.10 Record Types
2301 * @since 14
2302 */
2303 @jdk.internal.PreviewFeature(feature=jdk.internal.PreviewFeature.Feature.RECORDS,
2304 essentialAPI=false)
2305 @SuppressWarnings("preview")
2306 @CallerSensitive
2307 public RecordComponent[] getRecordComponents() {
2308 SecurityManager sm = System.getSecurityManager();
2309 if (sm != null) {
2310 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2311 }
2312 if (isPrimitive() || isArray()) {
2313 return new RecordComponent[0];
2314 }
2315 Object[] recordComponents = getRecordComponents0();
2316 if (recordComponents == null || recordComponents.length == 0) {
2317 return new RecordComponent[0];
2318 }
2319 RecordComponent[] result = new RecordComponent[recordComponents.length];
2320 for (int i = 0; i < recordComponents.length; i++) {
2321 result[i] = (RecordComponent)recordComponents[i];
2322 }
2323 return result;
2324 }
2325
2326 /**
2327 * Returns an array containing {@code Method} objects reflecting all the
2328 * declared methods of the class or interface represented by this {@code
2329 * Class} object, including public, protected, default (package)
2330 * access, and private methods, but excluding inherited methods.
2331 *
2332 * <p> If this {@code Class} object represents a type that has multiple
2333 * declared methods with the same name and parameter types, but different
2334 * return types, then the returned array has a {@code Method} object for
2335 * each such method.
2336 *
2337 * <p> If this {@code Class} object represents a type that has a class
2338 * initialization method {@code <clinit>}, then the returned array does
2339 * <em>not</em> have a corresponding {@code Method} object.
2340 *
2341 * <p> If this {@code Class} object represents a class or interface with no
2342 * declared methods, then the returned array has length 0.
2343 *
2344 * <p> If this {@code Class} object represents an array type, a primitive
2345 * type, or void, then the returned array has length 0.
2346 *
2347 * <p> The elements in the returned array are not sorted and are not in any
2348 * particular order.
2349 *
2350 * @return the array of {@code Method} objects representing all the
2351 * declared methods of this class
2352 * @throws SecurityException
2353 * If a security manager, <i>s</i>, is present and any of the
2354 * following conditions is met:
2355 *
2356 * <ul>
2357 *
2358 * <li> the caller's class loader is not the same as the
2359 * class loader of this class and invocation of
2360 * {@link SecurityManager#checkPermission
2361 * s.checkPermission} method with
2362 * {@code RuntimePermission("accessDeclaredMembers")}
2363 * denies access to the declared methods within this class
2364 *
2365 * <li> the caller's class loader is not the same as or an
2366 * ancestor of the class loader for the current class and
2367 * invocation of {@link SecurityManager#checkPackageAccess
2368 * s.checkPackageAccess()} denies access to the package
2369 * of this class
2370 *
2371 * </ul>
2372 *
2373 * @jls 8.2 Class Members
2374 * @jls 8.4 Method Declarations
2375 * @since 1.1
2376 */
2377 @CallerSensitive
2378 public Method[] getDeclaredMethods() throws SecurityException {
2379 SecurityManager sm = System.getSecurityManager();
2380 if (sm != null) {
2381 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2382 }
2383 return copyMethods(privateGetDeclaredMethods(false));
2384 }
2385
2386
2387 /**
2388 * Returns an array of {@code Constructor} objects reflecting all the
2389 * constructors declared by the class represented by this
2390 * {@code Class} object. These are public, protected, default
2391 * (package) access, and private constructors. The elements in the array
2392 * returned are not sorted and are not in any particular order. If the
2393 * class has a default constructor, it is included in the returned array.
2394 * This method returns an array of length 0 if this {@code Class}
2395 * object represents an interface, a primitive type, an array class, or
2396 * void.
2397 *
2398 * <p> See <em>The Java Language Specification</em>, section 8.2.
2399 *
2400 * @return the array of {@code Constructor} objects representing all the
2401 * declared constructors of this class
2402 * @throws SecurityException
2403 * If a security manager, <i>s</i>, is present and any of the
2404 * following conditions is met:
2405 *
2406 * <ul>
2407 *
2408 * <li> the caller's class loader is not the same as the
2409 * class loader of this class and invocation of
2410 * {@link SecurityManager#checkPermission
2411 * s.checkPermission} method with
2412 * {@code RuntimePermission("accessDeclaredMembers")}
2413 * denies access to the declared constructors within this class
2414 *
2415 * <li> the caller's class loader is not the same as or an
2416 * ancestor of the class loader for the current class and
2417 * invocation of {@link SecurityManager#checkPackageAccess
2418 * s.checkPackageAccess()} denies access to the package
2419 * of this class
2420 *
2421 * </ul>
2422 *
2423 * @since 1.1
2424 */
2425 @CallerSensitive
2426 public Constructor<?>[] getDeclaredConstructors() throws SecurityException {
2427 SecurityManager sm = System.getSecurityManager();
2428 if (sm != null) {
2429 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2430 }
2431 return copyConstructors(privateGetDeclaredConstructors(false));
2432 }
2433
2434
2435 /**
2436 * Returns a {@code Field} object that reflects the specified declared
2437 * field of the class or interface represented by this {@code Class}
2438 * object. The {@code name} parameter is a {@code String} that specifies
2439 * the simple name of the desired field.
2440 *
2441 * <p> If this {@code Class} object represents an array type, then this
2442 * method does not find the {@code length} field of the array type.
2443 *
2444 * @param name the name of the field
2445 * @return the {@code Field} object for the specified field in this
2446 * class
2447 * @throws NoSuchFieldException if a field with the specified name is
2448 * not found.
2449 * @throws NullPointerException if {@code name} is {@code null}
2450 * @throws SecurityException
2451 * If a security manager, <i>s</i>, is present and any of the
2452 * following conditions is met:
2453 *
2454 * <ul>
2455 *
2456 * <li> the caller's class loader is not the same as the
2457 * class loader of this class and invocation of
2458 * {@link SecurityManager#checkPermission
2459 * s.checkPermission} method with
2460 * {@code RuntimePermission("accessDeclaredMembers")}
2461 * denies access to the declared field
2462 *
2463 * <li> the caller's class loader is not the same as or an
2464 * ancestor of the class loader for the current class and
2465 * invocation of {@link SecurityManager#checkPackageAccess
2466 * s.checkPackageAccess()} denies access to the package
2467 * of this class
2468 *
2469 * </ul>
2470 *
2471 * @since 1.1
2472 * @jls 8.2 Class Members
2473 * @jls 8.3 Field Declarations
2474 */
2475 @CallerSensitive
2476 public Field getDeclaredField(String name)
2477 throws NoSuchFieldException, SecurityException {
2478 Objects.requireNonNull(name);
2479 SecurityManager sm = System.getSecurityManager();
2480 if (sm != null) {
2481 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2482 }
2483 Field field = searchFields(privateGetDeclaredFields(false), name);
2484 if (field == null) {
2485 throw new NoSuchFieldException(name);
2486 }
2487 return getReflectionFactory().copyField(field);
2488 }
2489
2490
2491 /**
2492 * Returns a {@code Method} object that reflects the specified
2493 * declared method of the class or interface represented by this
2494 * {@code Class} object. The {@code name} parameter is a
2495 * {@code String} that specifies the simple name of the desired
2496 * method, and the {@code parameterTypes} parameter is an array of
2497 * {@code Class} objects that identify the method's formal parameter
2498 * types, in declared order. If more than one method with the same
2499 * parameter types is declared in a class, and one of these methods has a
2500 * return type that is more specific than any of the others, that method is
2501 * returned; otherwise one of the methods is chosen arbitrarily. If the
2502 * name is "<init>"or "<clinit>" a {@code NoSuchMethodException}
2503 * is raised.
2504 *
2505 * <p> If this {@code Class} object represents an array type, then this
2506 * method does not find the {@code clone()} method.
2507 *
2508 * @param name the name of the method
2509 * @param parameterTypes the parameter array
2510 * @return the {@code Method} object for the method of this class
2511 * matching the specified name and parameters
2512 * @throws NoSuchMethodException if a matching method is not found.
2513 * @throws NullPointerException if {@code name} is {@code null}
2514 * @throws SecurityException
2515 * If a security manager, <i>s</i>, is present and any of the
2516 * following conditions is met:
2517 *
2518 * <ul>
2519 *
2520 * <li> the caller's class loader is not the same as the
2521 * class loader of this class and invocation of
2522 * {@link SecurityManager#checkPermission
2523 * s.checkPermission} method with
2524 * {@code RuntimePermission("accessDeclaredMembers")}
2525 * denies access to the declared method
2526 *
2527 * <li> the caller's class loader is not the same as or an
2528 * ancestor of the class loader for the current class and
2529 * invocation of {@link SecurityManager#checkPackageAccess
2530 * s.checkPackageAccess()} denies access to the package
2531 * of this class
2532 *
2533 * </ul>
2534 *
2535 * @jls 8.2 Class Members
2536 * @jls 8.4 Method Declarations
2537 * @since 1.1
2538 */
2539 @CallerSensitive
2540 public Method getDeclaredMethod(String name, Class<?>... parameterTypes)
2541 throws NoSuchMethodException, SecurityException {
2542 Objects.requireNonNull(name);
2543 SecurityManager sm = System.getSecurityManager();
2544 if (sm != null) {
2545 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2546 }
2547 Method method = searchMethods(privateGetDeclaredMethods(false), name, parameterTypes);
2548 if (method == null) {
2549 throw new NoSuchMethodException(methodToString(name, parameterTypes));
2550 }
2551 return getReflectionFactory().copyMethod(method);
2552 }
2553
2554 /**
2555 * Returns the list of {@code Method} objects for the declared public
2556 * methods of this class or interface that have the specified method name
2557 * and parameter types.
2558 *
2559 * @param name the name of the method
2560 * @param parameterTypes the parameter array
2561 * @return the list of {@code Method} objects for the public methods of
2562 * this class matching the specified name and parameters
2563 */
2564 List<Method> getDeclaredPublicMethods(String name, Class<?>... parameterTypes) {
2565 Method[] methods = privateGetDeclaredMethods(/* publicOnly */ true);
2566 ReflectionFactory factory = getReflectionFactory();
2567 List<Method> result = new ArrayList<>();
2568 for (Method method : methods) {
2569 if (method.getName().equals(name)
2570 && Arrays.equals(
2571 factory.getExecutableSharedParameterTypes(method),
2572 parameterTypes)) {
2573 result.add(factory.copyMethod(method));
2574 }
2575 }
2576 return result;
2577 }
2578
2579 /**
2580 * Returns a {@code Constructor} object that reflects the specified
2581 * constructor of the class or interface represented by this
2582 * {@code Class} object. The {@code parameterTypes} parameter is
2583 * an array of {@code Class} objects that identify the constructor's
2584 * formal parameter types, in declared order.
2585 *
2586 * If this {@code Class} object represents an inner class
2587 * declared in a non-static context, the formal parameter types
2588 * include the explicit enclosing instance as the first parameter.
2589 *
2590 * @param parameterTypes the parameter array
2591 * @return The {@code Constructor} object for the constructor with the
2592 * specified parameter list
2593 * @throws NoSuchMethodException if a matching method is not found.
2594 * @throws SecurityException
2595 * If a security manager, <i>s</i>, is present and any of the
2596 * following conditions is met:
2597 *
2598 * <ul>
2599 *
2600 * <li> the caller's class loader is not the same as the
2601 * class loader of this class and invocation of
2602 * {@link SecurityManager#checkPermission
2603 * s.checkPermission} method with
2604 * {@code RuntimePermission("accessDeclaredMembers")}
2605 * denies access to the declared constructor
2606 *
2607 * <li> the caller's class loader is not the same as or an
2608 * ancestor of the class loader for the current class and
2609 * invocation of {@link SecurityManager#checkPackageAccess
2610 * s.checkPackageAccess()} denies access to the package
2611 * of this class
2612 *
2613 * </ul>
2614 *
2615 * @since 1.1
2616 */
2617 @CallerSensitive
2618 public Constructor<T> getDeclaredConstructor(Class<?>... parameterTypes)
2619 throws NoSuchMethodException, SecurityException
2620 {
2621 SecurityManager sm = System.getSecurityManager();
2622 if (sm != null) {
2623 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2624 }
2625
2626 return getReflectionFactory().copyConstructor(
2627 getConstructor0(parameterTypes, Member.DECLARED));
2628 }
2629
2630 /**
2631 * Finds a resource with a given name.
2632 *
2633 * <p> If this class is in a named {@link Module Module} then this method
2634 * will attempt to find the resource in the module. This is done by
2635 * delegating to the module's class loader {@link
2636 * ClassLoader#findResource(String,String) findResource(String,String)}
2637 * method, invoking it with the module name and the absolute name of the
2638 * resource. Resources in named modules are subject to the rules for
2639 * encapsulation specified in the {@code Module} {@link
2640 * Module#getResourceAsStream getResourceAsStream} method and so this
2641 * method returns {@code null} when the resource is a
2642 * non-"{@code .class}" resource in a package that is not open to the
2643 * caller's module.
2644 *
2645 * <p> Otherwise, if this class is not in a named module then the rules for
2646 * searching resources associated with a given class are implemented by the
2647 * defining {@linkplain ClassLoader class loader} of the class. This method
2648 * delegates to this object's class loader. If this object was loaded by
2649 * the bootstrap class loader, the method delegates to {@link
2650 * ClassLoader#getSystemResourceAsStream}.
2651 *
2652 * <p> Before delegation, an absolute resource name is constructed from the
2653 * given resource name using this algorithm:
2654 *
2655 * <ul>
2656 *
2657 * <li> If the {@code name} begins with a {@code '/'}
2658 * (<code>'\u002f'</code>), then the absolute name of the resource is the
2659 * portion of the {@code name} following the {@code '/'}.
2660 *
2661 * <li> Otherwise, the absolute name is of the following form:
2662 *
2663 * <blockquote>
2664 * {@code modified_package_name/name}
2665 * </blockquote>
2666 *
2667 * <p> Where the {@code modified_package_name} is the package name of this
2668 * object with {@code '/'} substituted for {@code '.'}
2669 * (<code>'\u002e'</code>).
2670 *
2671 * </ul>
2672 *
2673 * @param name name of the desired resource
2674 * @return A {@link java.io.InputStream} object; {@code null} if no
2675 * resource with this name is found, the resource is in a package
2676 * that is not {@linkplain Module#isOpen(String, Module) open} to at
2677 * least the caller module, or access to the resource is denied
2678 * by the security manager.
2679 * @throws NullPointerException If {@code name} is {@code null}
2680 *
2681 * @see Module#getResourceAsStream(String)
2682 * @since 1.1
2683 * @revised 9
2684 * @spec JPMS
2685 */
2686 @CallerSensitive
2687 public InputStream getResourceAsStream(String name) {
2688 name = resolveName(name);
2689
2690 Module thisModule = getModule();
2691 if (thisModule.isNamed()) {
2692 // check if resource can be located by caller
2693 if (Resources.canEncapsulate(name)
2694 && !isOpenToCaller(name, Reflection.getCallerClass())) {
2695 return null;
2696 }
2697
2698 // resource not encapsulated or in package open to caller
2699 String mn = thisModule.getName();
2700 ClassLoader cl = getClassLoader0();
2701 try {
2702
2703 // special-case built-in class loaders to avoid the
2704 // need for a URL connection
2705 if (cl == null) {
2706 return BootLoader.findResourceAsStream(mn, name);
2707 } else if (cl instanceof BuiltinClassLoader) {
2708 return ((BuiltinClassLoader) cl).findResourceAsStream(mn, name);
2709 } else {
2710 URL url = cl.findResource(mn, name);
2711 return (url != null) ? url.openStream() : null;
2712 }
2713
2714 } catch (IOException | SecurityException e) {
2715 return null;
2716 }
2717 }
2718
2719 // unnamed module
2720 ClassLoader cl = getClassLoader0();
2721 if (cl == null) {
2722 return ClassLoader.getSystemResourceAsStream(name);
2723 } else {
2724 return cl.getResourceAsStream(name);
2725 }
2726 }
2727
2728 /**
2729 * Finds a resource with a given name.
2730 *
2731 * <p> If this class is in a named {@link Module Module} then this method
2732 * will attempt to find the resource in the module. This is done by
2733 * delegating to the module's class loader {@link
2734 * ClassLoader#findResource(String,String) findResource(String,String)}
2735 * method, invoking it with the module name and the absolute name of the
2736 * resource. Resources in named modules are subject to the rules for
2737 * encapsulation specified in the {@code Module} {@link
2738 * Module#getResourceAsStream getResourceAsStream} method and so this
2739 * method returns {@code null} when the resource is a
2740 * non-"{@code .class}" resource in a package that is not open to the
2741 * caller's module.
2742 *
2743 * <p> Otherwise, if this class is not in a named module then the rules for
2744 * searching resources associated with a given class are implemented by the
2745 * defining {@linkplain ClassLoader class loader} of the class. This method
2746 * delegates to this object's class loader. If this object was loaded by
2747 * the bootstrap class loader, the method delegates to {@link
2748 * ClassLoader#getSystemResource}.
2749 *
2750 * <p> Before delegation, an absolute resource name is constructed from the
2751 * given resource name using this algorithm:
2752 *
2753 * <ul>
2754 *
2755 * <li> If the {@code name} begins with a {@code '/'}
2756 * (<code>'\u002f'</code>), then the absolute name of the resource is the
2757 * portion of the {@code name} following the {@code '/'}.
2758 *
2759 * <li> Otherwise, the absolute name is of the following form:
2760 *
2761 * <blockquote>
2762 * {@code modified_package_name/name}
2763 * </blockquote>
2764 *
2765 * <p> Where the {@code modified_package_name} is the package name of this
2766 * object with {@code '/'} substituted for {@code '.'}
2767 * (<code>'\u002e'</code>).
2768 *
2769 * </ul>
2770 *
2771 * @param name name of the desired resource
2772 * @return A {@link java.net.URL} object; {@code null} if no resource with
2773 * this name is found, the resource cannot be located by a URL, the
2774 * resource is in a package that is not
2775 * {@linkplain Module#isOpen(String, Module) open} to at least the caller
2776 * module, or access to the resource is denied by the security
2777 * manager.
2778 * @throws NullPointerException If {@code name} is {@code null}
2779 * @since 1.1
2780 * @revised 9
2781 * @spec JPMS
2782 */
2783 @CallerSensitive
2784 public URL getResource(String name) {
2785 name = resolveName(name);
2786
2787 Module thisModule = getModule();
2788 if (thisModule.isNamed()) {
2789 // check if resource can be located by caller
2790 if (Resources.canEncapsulate(name)
2791 && !isOpenToCaller(name, Reflection.getCallerClass())) {
2792 return null;
2793 }
2794
2795 // resource not encapsulated or in package open to caller
2796 String mn = thisModule.getName();
2797 ClassLoader cl = getClassLoader0();
2798 try {
2799 if (cl == null) {
2800 return BootLoader.findResource(mn, name);
2801 } else {
2802 return cl.findResource(mn, name);
2803 }
2804 } catch (IOException ioe) {
2805 return null;
2806 }
2807 }
2808
2809 // unnamed module
2810 ClassLoader cl = getClassLoader0();
2811 if (cl == null) {
2812 return ClassLoader.getSystemResource(name);
2813 } else {
2814 return cl.getResource(name);
2815 }
2816 }
2817
2818 /**
2819 * Returns true if a resource with the given name can be located by the
2820 * given caller. All resources in a module can be located by code in
2821 * the module. For other callers, then the package needs to be open to
2822 * the caller.
2823 */
2824 private boolean isOpenToCaller(String name, Class<?> caller) {
2825 // assert getModule().isNamed();
2826 Module thisModule = getModule();
2827 Module callerModule = (caller != null) ? caller.getModule() : null;
2828 if (callerModule != thisModule) {
2829 String pn = Resources.toPackageName(name);
2830 if (thisModule.getDescriptor().packages().contains(pn)) {
2831 if (callerModule == null && !thisModule.isOpen(pn)) {
2832 // no caller, package not open
2833 return false;
2834 }
2835 if (!thisModule.isOpen(pn, callerModule)) {
2836 // package not open to caller
2837 return false;
2838 }
2839 }
2840 }
2841 return true;
2842 }
2843
2844
2845 /** protection domain returned when the internal domain is null */
2846 private static java.security.ProtectionDomain allPermDomain;
2847
2848 /**
2849 * Returns the {@code ProtectionDomain} of this class. If there is a
2850 * security manager installed, this method first calls the security
2851 * manager's {@code checkPermission} method with a
2852 * {@code RuntimePermission("getProtectionDomain")} permission to
2853 * ensure it's ok to get the
2854 * {@code ProtectionDomain}.
2855 *
2856 * @return the ProtectionDomain of this class
2857 *
2858 * @throws SecurityException
2859 * if a security manager exists and its
2860 * {@code checkPermission} method doesn't allow
2861 * getting the ProtectionDomain.
2862 *
2863 * @see java.security.ProtectionDomain
2864 * @see SecurityManager#checkPermission
2865 * @see java.lang.RuntimePermission
2866 * @since 1.2
2867 */
2868 public java.security.ProtectionDomain getProtectionDomain() {
2869 SecurityManager sm = System.getSecurityManager();
2870 if (sm != null) {
2871 sm.checkPermission(SecurityConstants.GET_PD_PERMISSION);
2872 }
2873 java.security.ProtectionDomain pd = getProtectionDomain0();
2874 if (pd == null) {
2875 if (allPermDomain == null) {
2876 java.security.Permissions perms =
2877 new java.security.Permissions();
2878 perms.add(SecurityConstants.ALL_PERMISSION);
2879 allPermDomain =
2880 new java.security.ProtectionDomain(null, perms);
2881 }
2882 pd = allPermDomain;
2883 }
2884 return pd;
2885 }
2886
2887
2888 /**
2889 * Returns the ProtectionDomain of this class.
2890 */
2891 private native java.security.ProtectionDomain getProtectionDomain0();
2892
2893 /*
2894 * Return the Virtual Machine's Class object for the named
2895 * primitive type.
2896 */
2897 static native Class<?> getPrimitiveClass(String name);
2898
2899 /*
2900 * Check if client is allowed to access members. If access is denied,
2901 * throw a SecurityException.
2902 *
2903 * This method also enforces package access.
2904 *
2905 * <p> Default policy: allow all clients access with normal Java access
2906 * control.
2907 *
2908 * <p> NOTE: should only be called if a SecurityManager is installed
2909 */
2910 private void checkMemberAccess(SecurityManager sm, int which,
2911 Class<?> caller, boolean checkProxyInterfaces) {
2912 /* Default policy allows access to all {@link Member#PUBLIC} members,
2913 * as well as access to classes that have the same class loader as the caller.
2914 * In all other cases, it requires RuntimePermission("accessDeclaredMembers")
2915 * permission.
2916 */
2917 final ClassLoader ccl = ClassLoader.getClassLoader(caller);
2918 if (which != Member.PUBLIC) {
2919 final ClassLoader cl = getClassLoader0();
2920 if (ccl != cl) {
2921 sm.checkPermission(SecurityConstants.CHECK_MEMBER_ACCESS_PERMISSION);
2922 }
2923 }
2924 this.checkPackageAccess(sm, ccl, checkProxyInterfaces);
2925 }
2926
2927 /*
2928 * Checks if a client loaded in ClassLoader ccl is allowed to access this
2929 * class under the current package access policy. If access is denied,
2930 * throw a SecurityException.
2931 *
2932 * NOTE: this method should only be called if a SecurityManager is active
2933 */
2934 private void checkPackageAccess(SecurityManager sm, final ClassLoader ccl,
2935 boolean checkProxyInterfaces) {
2936 final ClassLoader cl = getClassLoader0();
2937
2938 if (ReflectUtil.needsPackageAccessCheck(ccl, cl)) {
2939 String pkg = this.getPackageName();
2940 if (pkg != null && !pkg.isEmpty()) {
2941 // skip the package access check on a proxy class in default proxy package
2942 if (!Proxy.isProxyClass(this) || ReflectUtil.isNonPublicProxyClass(this)) {
2943 sm.checkPackageAccess(pkg);
2944 }
2945 }
2946 }
2947 // check package access on the proxy interfaces
2948 if (checkProxyInterfaces && Proxy.isProxyClass(this)) {
2949 ReflectUtil.checkProxyPackageAccess(ccl, this.getInterfaces());
2950 }
2951 }
2952
2953 /**
2954 * Add a package name prefix if the name is not absolute Remove leading "/"
2955 * if name is absolute
2956 */
2957 private String resolveName(String name) {
2958 if (!name.startsWith("/")) {
2959 Class<?> c = this;
2960 while (c.isArray()) {
2961 c = c.getComponentType();
2962 }
2963 String baseName = c.getPackageName();
2964 if (baseName != null && !baseName.isEmpty()) {
2965 name = baseName.replace('.', '/') + "/" + name;
2966 }
2967 } else {
2968 name = name.substring(1);
2969 }
2970 return name;
2971 }
2972
2973 /**
2974 * Atomic operations support.
2975 */
2976 private static class Atomic {
2977 // initialize Unsafe machinery here, since we need to call Class.class instance method
2978 // and have to avoid calling it in the static initializer of the Class class...
2979 private static final Unsafe unsafe = Unsafe.getUnsafe();
2980 // offset of Class.reflectionData instance field
2981 private static final long reflectionDataOffset
2982 = unsafe.objectFieldOffset(Class.class, "reflectionData");
2983 // offset of Class.annotationType instance field
2984 private static final long annotationTypeOffset
2985 = unsafe.objectFieldOffset(Class.class, "annotationType");
2986 // offset of Class.annotationData instance field
2987 private static final long annotationDataOffset
2988 = unsafe.objectFieldOffset(Class.class, "annotationData");
2989
2990 static <T> boolean casReflectionData(Class<?> clazz,
2991 SoftReference<ReflectionData<T>> oldData,
2992 SoftReference<ReflectionData<T>> newData) {
2993 return unsafe.compareAndSetReference(clazz, reflectionDataOffset, oldData, newData);
2994 }
2995
2996 static <T> boolean casAnnotationType(Class<?> clazz,
2997 AnnotationType oldType,
2998 AnnotationType newType) {
2999 return unsafe.compareAndSetReference(clazz, annotationTypeOffset, oldType, newType);
3000 }
3001
3002 static <T> boolean casAnnotationData(Class<?> clazz,
3003 AnnotationData oldData,
3004 AnnotationData newData) {
3005 return unsafe.compareAndSetReference(clazz, annotationDataOffset, oldData, newData);
3006 }
3007 }
3008
3009 /**
3010 * Reflection support.
3011 */
3012
3013 // Reflection data caches various derived names and reflective members. Cached
3014 // values may be invalidated when JVM TI RedefineClasses() is called
3015 private static class ReflectionData<T> {
3016 volatile Field[] declaredFields;
3017 volatile Field[] publicFields;
3018 volatile Method[] declaredMethods;
3019 volatile Method[] publicMethods;
3020 volatile Constructor<T>[] declaredConstructors;
3021 volatile Constructor<T>[] publicConstructors;
3022 // Intermediate results for getFields and getMethods
3023 volatile Field[] declaredPublicFields;
3024 volatile Method[] declaredPublicMethods;
3025 volatile Class<?>[] interfaces;
3026
3027 // Cached names
3028 String simpleName;
3029 String canonicalName;
3030 static final String NULL_SENTINEL = new String();
3031
3032 // Value of classRedefinedCount when we created this ReflectionData instance
3033 final int redefinedCount;
3034
3035 ReflectionData(int redefinedCount) {
3036 this.redefinedCount = redefinedCount;
3037 }
3038 }
3039
3040 private transient volatile SoftReference<ReflectionData<T>> reflectionData;
3041
3042 // Incremented by the VM on each call to JVM TI RedefineClasses()
3043 // that redefines this class or a superclass.
3044 private transient volatile int classRedefinedCount;
3045
3046 // Lazily create and cache ReflectionData
3047 private ReflectionData<T> reflectionData() {
3048 SoftReference<ReflectionData<T>> reflectionData = this.reflectionData;
3049 int classRedefinedCount = this.classRedefinedCount;
3050 ReflectionData<T> rd;
3051 if (reflectionData != null &&
3052 (rd = reflectionData.get()) != null &&
3053 rd.redefinedCount == classRedefinedCount) {
3054 return rd;
3055 }
3056 // else no SoftReference or cleared SoftReference or stale ReflectionData
3057 // -> create and replace new instance
3058 return newReflectionData(reflectionData, classRedefinedCount);
3059 }
3060
3061 private ReflectionData<T> newReflectionData(SoftReference<ReflectionData<T>> oldReflectionData,
3062 int classRedefinedCount) {
3063 while (true) {
3064 ReflectionData<T> rd = new ReflectionData<>(classRedefinedCount);
3065 // try to CAS it...
3066 if (Atomic.casReflectionData(this, oldReflectionData, new SoftReference<>(rd))) {
3067 return rd;
3068 }
3069 // else retry
3070 oldReflectionData = this.reflectionData;
3071 classRedefinedCount = this.classRedefinedCount;
3072 if (oldReflectionData != null &&
3073 (rd = oldReflectionData.get()) != null &&
3074 rd.redefinedCount == classRedefinedCount) {
3075 return rd;
3076 }
3077 }
3078 }
3079
3080 // Generic signature handling
3081 private native String getGenericSignature0();
3082
3083 // Generic info repository; lazily initialized
3084 private transient volatile ClassRepository genericInfo;
3085
3086 // accessor for factory
3087 private GenericsFactory getFactory() {
3088 // create scope and factory
3089 return CoreReflectionFactory.make(this, ClassScope.make(this));
3090 }
3091
3092 // accessor for generic info repository;
3093 // generic info is lazily initialized
3094 private ClassRepository getGenericInfo() {
3095 ClassRepository genericInfo = this.genericInfo;
3096 if (genericInfo == null) {
3097 String signature = getGenericSignature0();
3098 if (signature == null) {
3099 genericInfo = ClassRepository.NONE;
3100 } else {
3101 genericInfo = ClassRepository.make(signature, getFactory());
3102 }
3103 this.genericInfo = genericInfo;
3104 }
3105 return (genericInfo != ClassRepository.NONE) ? genericInfo : null;
3106 }
3107
3108 // Annotations handling
3109 native byte[] getRawAnnotations();
3110 // Since 1.8
3111 native byte[] getRawTypeAnnotations();
3112 static byte[] getExecutableTypeAnnotationBytes(Executable ex) {
3113 return getReflectionFactory().getExecutableTypeAnnotationBytes(ex);
3114 }
3115
3116 native ConstantPool getConstantPool();
3117
3118 //
3119 //
3120 // java.lang.reflect.Field handling
3121 //
3122 //
3123
3124 // Returns an array of "root" fields. These Field objects must NOT
3125 // be propagated to the outside world, but must instead be copied
3126 // via ReflectionFactory.copyField.
3127 private Field[] privateGetDeclaredFields(boolean publicOnly) {
3128 Field[] res;
3129 ReflectionData<T> rd = reflectionData();
3130 if (rd != null) {
3131 res = publicOnly ? rd.declaredPublicFields : rd.declaredFields;
3132 if (res != null) return res;
3133 }
3134 // No cached value available; request value from VM
3135 res = Reflection.filterFields(this, getDeclaredFields0(publicOnly));
3136 if (rd != null) {
3137 if (publicOnly) {
3138 rd.declaredPublicFields = res;
3139 } else {
3140 rd.declaredFields = res;
3141 }
3142 }
3143 return res;
3144 }
3145
3146 // Returns an array of "root" fields. These Field objects must NOT
3147 // be propagated to the outside world, but must instead be copied
3148 // via ReflectionFactory.copyField.
3149 private Field[] privateGetPublicFields() {
3150 Field[] res;
3151 ReflectionData<T> rd = reflectionData();
3152 if (rd != null) {
3153 res = rd.publicFields;
3154 if (res != null) return res;
3155 }
3156
3157 // Use a linked hash set to ensure order is preserved and
3158 // fields from common super interfaces are not duplicated
3159 LinkedHashSet<Field> fields = new LinkedHashSet<>();
3160
3161 // Local fields
3162 addAll(fields, privateGetDeclaredFields(true));
3163
3164 // Direct superinterfaces, recursively
3165 for (Class<?> si : getInterfaces()) {
3166 addAll(fields, si.privateGetPublicFields());
3167 }
3168
3169 // Direct superclass, recursively
3170 Class<?> sc = getSuperclass();
3171 if (sc != null) {
3172 addAll(fields, sc.privateGetPublicFields());
3173 }
3174
3175 res = fields.toArray(new Field[0]);
3176 if (rd != null) {
3177 rd.publicFields = res;
3178 }
3179 return res;
3180 }
3181
3182 private static void addAll(Collection<Field> c, Field[] o) {
3183 for (Field f : o) {
3184 c.add(f);
3185 }
3186 }
3187
3188
3189 //
3190 //
3191 // java.lang.reflect.Constructor handling
3192 //
3193 //
3194
3195 // Returns an array of "root" constructors. These Constructor
3196 // objects must NOT be propagated to the outside world, but must
3197 // instead be copied via ReflectionFactory.copyConstructor.
3198 private Constructor<T>[] privateGetDeclaredConstructors(boolean publicOnly) {
3199 Constructor<T>[] res;
3200 ReflectionData<T> rd = reflectionData();
3201 if (rd != null) {
3202 res = publicOnly ? rd.publicConstructors : rd.declaredConstructors;
3203 if (res != null) return res;
3204 }
3205 // No cached value available; request value from VM
3206 if (isInterface()) {
3207 @SuppressWarnings("unchecked")
3208 Constructor<T>[] temporaryRes = (Constructor<T>[]) new Constructor<?>[0];
3209 res = temporaryRes;
3210 } else {
3211 res = getDeclaredConstructors0(publicOnly);
3212 }
3213 if (rd != null) {
3214 if (publicOnly) {
3215 rd.publicConstructors = res;
3216 } else {
3217 rd.declaredConstructors = res;
3218 }
3219 }
3220 return res;
3221 }
3222
3223 //
3224 //
3225 // java.lang.reflect.Method handling
3226 //
3227 //
3228
3229 // Returns an array of "root" methods. These Method objects must NOT
3230 // be propagated to the outside world, but must instead be copied
3231 // via ReflectionFactory.copyMethod.
3232 private Method[] privateGetDeclaredMethods(boolean publicOnly) {
3233 Method[] res;
3234 ReflectionData<T> rd = reflectionData();
3235 if (rd != null) {
3236 res = publicOnly ? rd.declaredPublicMethods : rd.declaredMethods;
3237 if (res != null) return res;
3238 }
3239 // No cached value available; request value from VM
3240 res = Reflection.filterMethods(this, getDeclaredMethods0(publicOnly));
3241 if (rd != null) {
3242 if (publicOnly) {
3243 rd.declaredPublicMethods = res;
3244 } else {
3245 rd.declaredMethods = res;
3246 }
3247 }
3248 return res;
3249 }
3250
3251 // Returns an array of "root" methods. These Method objects must NOT
3252 // be propagated to the outside world, but must instead be copied
3253 // via ReflectionFactory.copyMethod.
3254 private Method[] privateGetPublicMethods() {
3255 Method[] res;
3256 ReflectionData<T> rd = reflectionData();
3257 if (rd != null) {
3258 res = rd.publicMethods;
3259 if (res != null) return res;
3260 }
3261
3262 // No cached value available; compute value recursively.
3263 // Start by fetching public declared methods...
3264 PublicMethods pms = new PublicMethods();
3265 for (Method m : privateGetDeclaredMethods(/* publicOnly */ true)) {
3266 pms.merge(m);
3267 }
3268 // ...then recur over superclass methods...
3269 Class<?> sc = getSuperclass();
3270 if (sc != null) {
3271 for (Method m : sc.privateGetPublicMethods()) {
3272 pms.merge(m);
3273 }
3274 }
3275 // ...and finally over direct superinterfaces.
3276 for (Class<?> intf : getInterfaces(/* cloneArray */ false)) {
3277 for (Method m : intf.privateGetPublicMethods()) {
3278 // static interface methods are not inherited
3279 if (!Modifier.isStatic(m.getModifiers())) {
3280 pms.merge(m);
3281 }
3282 }
3283 }
3284
3285 res = pms.toArray();
3286 if (rd != null) {
3287 rd.publicMethods = res;
3288 }
3289 return res;
3290 }
3291
3292
3293 //
3294 // Helpers for fetchers of one field, method, or constructor
3295 //
3296
3297 // This method does not copy the returned Field object!
3298 private static Field searchFields(Field[] fields, String name) {
3299 for (Field field : fields) {
3300 if (field.getName().equals(name)) {
3301 return field;
3302 }
3303 }
3304 return null;
3305 }
3306
3307 // Returns a "root" Field object. This Field object must NOT
3308 // be propagated to the outside world, but must instead be copied
3309 // via ReflectionFactory.copyField.
3310 private Field getField0(String name) {
3311 // Note: the intent is that the search algorithm this routine
3312 // uses be equivalent to the ordering imposed by
3313 // privateGetPublicFields(). It fetches only the declared
3314 // public fields for each class, however, to reduce the number
3315 // of Field objects which have to be created for the common
3316 // case where the field being requested is declared in the
3317 // class which is being queried.
3318 Field res;
3319 // Search declared public fields
3320 if ((res = searchFields(privateGetDeclaredFields(true), name)) != null) {
3321 return res;
3322 }
3323 // Direct superinterfaces, recursively
3324 Class<?>[] interfaces = getInterfaces(/* cloneArray */ false);
3325 for (Class<?> c : interfaces) {
3326 if ((res = c.getField0(name)) != null) {
3327 return res;
3328 }
3329 }
3330 // Direct superclass, recursively
3331 if (!isInterface()) {
3332 Class<?> c = getSuperclass();
3333 if (c != null) {
3334 if ((res = c.getField0(name)) != null) {
3335 return res;
3336 }
3337 }
3338 }
3339 return null;
3340 }
3341
3342 // This method does not copy the returned Method object!
3343 private static Method searchMethods(Method[] methods,
3344 String name,
3345 Class<?>[] parameterTypes)
3346 {
3347 ReflectionFactory fact = getReflectionFactory();
3348 Method res = null;
3349 for (Method m : methods) {
3350 if (m.getName().equals(name)
3351 && arrayContentsEq(parameterTypes,
3352 fact.getExecutableSharedParameterTypes(m))
3353 && (res == null
3354 || (res.getReturnType() != m.getReturnType()
3355 && res.getReturnType().isAssignableFrom(m.getReturnType()))))
3356 res = m;
3357 }
3358 return res;
3359 }
3360
3361 private static final Class<?>[] EMPTY_CLASS_ARRAY = new Class<?>[0];
3362
3363 // Returns a "root" Method object. This Method object must NOT
3364 // be propagated to the outside world, but must instead be copied
3365 // via ReflectionFactory.copyMethod.
3366 private Method getMethod0(String name, Class<?>[] parameterTypes) {
3367 PublicMethods.MethodList res = getMethodsRecursive(
3368 name,
3369 parameterTypes == null ? EMPTY_CLASS_ARRAY : parameterTypes,
3370 /* includeStatic */ true);
3371 return res == null ? null : res.getMostSpecific();
3372 }
3373
3374 // Returns a list of "root" Method objects. These Method objects must NOT
3375 // be propagated to the outside world, but must instead be copied
3376 // via ReflectionFactory.copyMethod.
3377 private PublicMethods.MethodList getMethodsRecursive(String name,
3378 Class<?>[] parameterTypes,
3379 boolean includeStatic) {
3380 // 1st check declared public methods
3381 Method[] methods = privateGetDeclaredMethods(/* publicOnly */ true);
3382 PublicMethods.MethodList res = PublicMethods.MethodList
3383 .filter(methods, name, parameterTypes, includeStatic);
3384 // if there is at least one match among declared methods, we need not
3385 // search any further as such match surely overrides matching methods
3386 // declared in superclass(es) or interface(s).
3387 if (res != null) {
3388 return res;
3389 }
3390
3391 // if there was no match among declared methods,
3392 // we must consult the superclass (if any) recursively...
3393 Class<?> sc = getSuperclass();
3394 if (sc != null) {
3395 res = sc.getMethodsRecursive(name, parameterTypes, includeStatic);
3396 }
3397
3398 // ...and coalesce the superclass methods with methods obtained
3399 // from directly implemented interfaces excluding static methods...
3400 for (Class<?> intf : getInterfaces(/* cloneArray */ false)) {
3401 res = PublicMethods.MethodList.merge(
3402 res, intf.getMethodsRecursive(name, parameterTypes,
3403 /* includeStatic */ false));
3404 }
3405
3406 return res;
3407 }
3408
3409 // Returns a "root" Constructor object. This Constructor object must NOT
3410 // be propagated to the outside world, but must instead be copied
3411 // via ReflectionFactory.copyConstructor.
3412 private Constructor<T> getConstructor0(Class<?>[] parameterTypes,
3413 int which) throws NoSuchMethodException
3414 {
3415 ReflectionFactory fact = getReflectionFactory();
3416 Constructor<T>[] constructors = privateGetDeclaredConstructors((which == Member.PUBLIC));
3417 for (Constructor<T> constructor : constructors) {
3418 if (arrayContentsEq(parameterTypes,
3419 fact.getExecutableSharedParameterTypes(constructor))) {
3420 return constructor;
3421 }
3422 }
3423 throw new NoSuchMethodException(methodToString("<init>", parameterTypes));
3424 }
3425
3426 //
3427 // Other helpers and base implementation
3428 //
3429
3430 private static boolean arrayContentsEq(Object[] a1, Object[] a2) {
3431 if (a1 == null) {
3432 return a2 == null || a2.length == 0;
3433 }
3434
3435 if (a2 == null) {
3436 return a1.length == 0;
3437 }
3438
3439 if (a1.length != a2.length) {
3440 return false;
3441 }
3442
3443 for (int i = 0; i < a1.length; i++) {
3444 if (a1[i] != a2[i]) {
3445 return false;
3446 }
3447 }
3448
3449 return true;
3450 }
3451
3452 private static Field[] copyFields(Field[] arg) {
3453 Field[] out = new Field[arg.length];
3454 ReflectionFactory fact = getReflectionFactory();
3455 for (int i = 0; i < arg.length; i++) {
3456 out[i] = fact.copyField(arg[i]);
3457 }
3458 return out;
3459 }
3460
3461 private static Method[] copyMethods(Method[] arg) {
3462 Method[] out = new Method[arg.length];
3463 ReflectionFactory fact = getReflectionFactory();
3464 for (int i = 0; i < arg.length; i++) {
3465 out[i] = fact.copyMethod(arg[i]);
3466 }
3467 return out;
3468 }
3469
3470 private static <U> Constructor<U>[] copyConstructors(Constructor<U>[] arg) {
3471 Constructor<U>[] out = arg.clone();
3472 ReflectionFactory fact = getReflectionFactory();
3473 for (int i = 0; i < out.length; i++) {
3474 out[i] = fact.copyConstructor(out[i]);
3475 }
3476 return out;
3477 }
3478
3479 private native Field[] getDeclaredFields0(boolean publicOnly);
3480 private native Method[] getDeclaredMethods0(boolean publicOnly);
3481 private native Constructor<T>[] getDeclaredConstructors0(boolean publicOnly);
3482 private native Class<?>[] getDeclaredClasses0();
3483 private native Object[] getRecordComponents0();
3484 private native boolean isRecord0();
3485
3486 /**
3487 * Helper method to get the method name from arguments.
3488 */
3489 private String methodToString(String name, Class<?>[] argTypes) {
3490 return getName() + '.' + name +
3491 ((argTypes == null || argTypes.length == 0) ?
3492 "()" :
3493 Arrays.stream(argTypes)
3494 .map(c -> c == null ? "null" : c.getName())
3495 .collect(Collectors.joining(",", "(", ")")));
3496 }
3497
3498 /** use serialVersionUID from JDK 1.1 for interoperability */
3499 @java.io.Serial
3500 private static final long serialVersionUID = 3206093459760846163L;
3501
3502
3503 /**
3504 * Class Class is special cased within the Serialization Stream Protocol.
3505 *
3506 * A Class instance is written initially into an ObjectOutputStream in the
3507 * following format:
3508 * <pre>
3509 * {@code TC_CLASS} ClassDescriptor
3510 * A ClassDescriptor is a special cased serialization of
3511 * a {@code java.io.ObjectStreamClass} instance.
3512 * </pre>
3513 * A new handle is generated for the initial time the class descriptor
3514 * is written into the stream. Future references to the class descriptor
3515 * are written as references to the initial class descriptor instance.
3516 *
3517 * @see java.io.ObjectStreamClass
3518 */
3519 @java.io.Serial
3520 private static final ObjectStreamField[] serialPersistentFields =
3521 new ObjectStreamField[0];
3522
3523
3524 /**
3525 * Returns the assertion status that would be assigned to this
3526 * class if it were to be initialized at the time this method is invoked.
3527 * If this class has had its assertion status set, the most recent
3528 * setting will be returned; otherwise, if any package default assertion
3529 * status pertains to this class, the most recent setting for the most
3530 * specific pertinent package default assertion status is returned;
3531 * otherwise, if this class is not a system class (i.e., it has a
3532 * class loader) its class loader's default assertion status is returned;
3533 * otherwise, the system class default assertion status is returned.
3534 * <p>
3535 * Few programmers will have any need for this method; it is provided
3536 * for the benefit of the JRE itself. (It allows a class to determine at
3537 * the time that it is initialized whether assertions should be enabled.)
3538 * Note that this method is not guaranteed to return the actual
3539 * assertion status that was (or will be) associated with the specified
3540 * class when it was (or will be) initialized.
3541 *
3542 * @return the desired assertion status of the specified class.
3543 * @see java.lang.ClassLoader#setClassAssertionStatus
3544 * @see java.lang.ClassLoader#setPackageAssertionStatus
3545 * @see java.lang.ClassLoader#setDefaultAssertionStatus
3546 * @since 1.4
3547 */
3548 public boolean desiredAssertionStatus() {
3549 ClassLoader loader = getClassLoader0();
3550 // If the loader is null this is a system class, so ask the VM
3551 if (loader == null)
3552 return desiredAssertionStatus0(this);
3553
3554 // If the classloader has been initialized with the assertion
3555 // directives, ask it. Otherwise, ask the VM.
3556 synchronized(loader.assertionLock) {
3557 if (loader.classAssertionStatus != null) {
3558 return loader.desiredAssertionStatus(getName());
3559 }
3560 }
3561 return desiredAssertionStatus0(this);
3562 }
3563
3564 // Retrieves the desired assertion status of this class from the VM
3565 private static native boolean desiredAssertionStatus0(Class<?> clazz);
3566
3567 /**
3568 * Returns true if and only if this class was declared as an enum in the
3569 * source code.
3570 *
3571 * Note that {@link java.lang.Enum} is not itself an enum type.
3572 *
3573 * Also note that if an enum constant is declared with a class body,
3574 * the class of that enum constant object is an anonymous class
3575 * and <em>not</em> the class of the declaring enum type. The
3576 * {@link Enum#getDeclaringClass} method of an enum constant can
3577 * be used to get the class of the enum type declaring the
3578 * constant.
3579 *
3580 * @return true if and only if this class was declared as an enum in the
3581 * source code
3582 * @since 1.5
3583 * @jls 8.9.1 Enum Constants
3584 */
3585 public boolean isEnum() {
3586 // An enum must both directly extend java.lang.Enum and have
3587 // the ENUM bit set; classes for specialized enum constants
3588 // don't do the former.
3589 return (this.getModifiers() & ENUM) != 0 &&
3590 this.getSuperclass() == java.lang.Enum.class;
3591 }
3592
3593 /**
3594 * {@preview Associated with records, a preview feature of the Java language.
3595 *
3596 * This method is associated with <i>records</i>, a preview
3597 * feature of the Java language. Preview features
3598 * may be removed in a future release, or upgraded to permanent
3599 * features of the Java language.}
3600 *
3601 * Returns {@code true} if and only if this class is a record class.
3602 * It returns {@code false} otherwise. Note that class {@link Record} is not a
3603 * record type and thus invoking this method on class {@link java.lang.Record}
3604 * returns {@code false}.
3605 *
3606 * @return true if and only if this class is a record class
3607 * @jls 8.10 Record Types
3608 * @since 14
3609 */
3610 @jdk.internal.PreviewFeature(feature=jdk.internal.PreviewFeature.Feature.RECORDS,
3611 essentialAPI=false)
3612 public boolean isRecord() {
3613 return isRecord0();
3614 }
3615
3616 // Fetches the factory for reflective objects
3617 private static ReflectionFactory getReflectionFactory() {
3618 if (reflectionFactory == null) {
3619 reflectionFactory =
3620 java.security.AccessController.doPrivileged
3621 (new ReflectionFactory.GetReflectionFactoryAction());
3622 }
3623 return reflectionFactory;
3624 }
3625 private static ReflectionFactory reflectionFactory;
3626
3627 /**
3628 * Returns the elements of this enum class or null if this
3629 * Class object does not represent an enum type.
3630 *
3631 * @return an array containing the values comprising the enum class
3632 * represented by this Class object in the order they're
3633 * declared, or null if this Class object does not
3634 * represent an enum type
3635 * @since 1.5
3636 */
3637 public T[] getEnumConstants() {
3638 T[] values = getEnumConstantsShared();
3639 return (values != null) ? values.clone() : null;
3640 }
3641
3642 /**
3643 * Returns the elements of this enum class or null if this
3644 * Class object does not represent an enum type;
3645 * identical to getEnumConstants except that the result is
3646 * uncloned, cached, and shared by all callers.
3647 */
3648 T[] getEnumConstantsShared() {
3649 T[] constants = enumConstants;
3650 if (constants == null) {
3651 if (!isEnum()) return null;
3652 try {
3653 final Method values = getMethod("values");
3654 java.security.AccessController.doPrivileged(
3655 new java.security.PrivilegedAction<>() {
3656 public Void run() {
3657 values.setAccessible(true);
3658 return null;
3659 }
3660 });
3661 @SuppressWarnings("unchecked")
3662 T[] temporaryConstants = (T[])values.invoke(null);
3663 enumConstants = constants = temporaryConstants;
3664 }
3665 // These can happen when users concoct enum-like classes
3666 // that don't comply with the enum spec.
3667 catch (InvocationTargetException | NoSuchMethodException |
3668 IllegalAccessException ex) { return null; }
3669 }
3670 return constants;
3671 }
3672 private transient volatile T[] enumConstants;
3673
3674 /**
3675 * Returns a map from simple name to enum constant. This package-private
3676 * method is used internally by Enum to implement
3677 * {@code public static <T extends Enum<T>> T valueOf(Class<T>, String)}
3678 * efficiently. Note that the map is returned by this method is
3679 * created lazily on first use. Typically it won't ever get created.
3680 */
3681 Map<String, T> enumConstantDirectory() {
3682 Map<String, T> directory = enumConstantDirectory;
3683 if (directory == null) {
3684 T[] universe = getEnumConstantsShared();
3685 if (universe == null)
3686 throw new IllegalArgumentException(
3687 getName() + " is not an enum type");
3688 directory = new HashMap<>((int)(universe.length / 0.75f) + 1);
3689 for (T constant : universe) {
3690 directory.put(((Enum<?>)constant).name(), constant);
3691 }
3692 enumConstantDirectory = directory;
3693 }
3694 return directory;
3695 }
3696 private transient volatile Map<String, T> enumConstantDirectory;
3697
3698 /**
3699 * Casts an object to the class or interface represented
3700 * by this {@code Class} object.
3701 *
3702 * @param obj the object to be cast
3703 * @return the object after casting, or null if obj is null
3704 *
3705 * @throws ClassCastException if the object is not
3706 * null and is not assignable to the type T.
3707 *
3708 * @since 1.5
3709 */
3710 @SuppressWarnings("unchecked")
3711 @HotSpotIntrinsicCandidate
3712 public T cast(Object obj) {
3713 if (obj != null && !isInstance(obj))
3714 throw new ClassCastException(cannotCastMsg(obj));
3715 return (T) obj;
3716 }
3717
3718 private String cannotCastMsg(Object obj) {
3719 return "Cannot cast " + obj.getClass().getName() + " to " + getName();
3720 }
3721
3722 /**
3723 * Casts this {@code Class} object to represent a subclass of the class
3724 * represented by the specified class object. Checks that the cast
3725 * is valid, and throws a {@code ClassCastException} if it is not. If
3726 * this method succeeds, it always returns a reference to this class object.
3727 *
3728 * <p>This method is useful when a client needs to "narrow" the type of
3729 * a {@code Class} object to pass it to an API that restricts the
3730 * {@code Class} objects that it is willing to accept. A cast would
3731 * generate a compile-time warning, as the correctness of the cast
3732 * could not be checked at runtime (because generic types are implemented
3733 * by erasure).
3734 *
3735 * @param <U> the type to cast this class object to
3736 * @param clazz the class of the type to cast this class object to
3737 * @return this {@code Class} object, cast to represent a subclass of
3738 * the specified class object.
3739 * @throws ClassCastException if this {@code Class} object does not
3740 * represent a subclass of the specified class (here "subclass" includes
3741 * the class itself).
3742 * @since 1.5
3743 */
3744 @SuppressWarnings("unchecked")
3745 public <U> Class<? extends U> asSubclass(Class<U> clazz) {
3746 if (clazz.isAssignableFrom(this))
3747 return (Class<? extends U>) this;
3748 else
3749 throw new ClassCastException(this.toString());
3750 }
3751
3752 /**
3753 * @throws NullPointerException {@inheritDoc}
3754 * @since 1.5
3755 */
3756 @SuppressWarnings("unchecked")
3757 public <A extends Annotation> A getAnnotation(Class<A> annotationClass) {
3758 Objects.requireNonNull(annotationClass);
3759
3760 return (A) annotationData().annotations.get(annotationClass);
3761 }
3762
3763 /**
3764 * {@inheritDoc}
3765 * @throws NullPointerException {@inheritDoc}
3766 * @since 1.5
3767 */
3768 @Override
3769 public boolean isAnnotationPresent(Class<? extends Annotation> annotationClass) {
3770 return GenericDeclaration.super.isAnnotationPresent(annotationClass);
3771 }
3772
3773 /**
3774 * @throws NullPointerException {@inheritDoc}
3775 * @since 1.8
3776 */
3777 @Override
3778 public <A extends Annotation> A[] getAnnotationsByType(Class<A> annotationClass) {
3779 Objects.requireNonNull(annotationClass);
3780
3781 AnnotationData annotationData = annotationData();
3782 return AnnotationSupport.getAssociatedAnnotations(annotationData.declaredAnnotations,
3783 this,
3784 annotationClass);
3785 }
3786
3787 /**
3788 * @since 1.5
3789 */
3790 public Annotation[] getAnnotations() {
3791 return AnnotationParser.toArray(annotationData().annotations);
3792 }
3793
3794 /**
3795 * @throws NullPointerException {@inheritDoc}
3796 * @since 1.8
3797 */
3798 @Override
3799 @SuppressWarnings("unchecked")
3800 public <A extends Annotation> A getDeclaredAnnotation(Class<A> annotationClass) {
3801 Objects.requireNonNull(annotationClass);
3802
3803 return (A) annotationData().declaredAnnotations.get(annotationClass);
3804 }
3805
3806 /**
3807 * @throws NullPointerException {@inheritDoc}
3808 * @since 1.8
3809 */
3810 @Override
3811 public <A extends Annotation> A[] getDeclaredAnnotationsByType(Class<A> annotationClass) {
3812 Objects.requireNonNull(annotationClass);
3813
3814 return AnnotationSupport.getDirectlyAndIndirectlyPresent(annotationData().declaredAnnotations,
3815 annotationClass);
3816 }
3817
3818 /**
3819 * @since 1.5
3820 */
3821 public Annotation[] getDeclaredAnnotations() {
3822 return AnnotationParser.toArray(annotationData().declaredAnnotations);
3823 }
3824
3825 // annotation data that might get invalidated when JVM TI RedefineClasses() is called
3826 private static class AnnotationData {
3827 final Map<Class<? extends Annotation>, Annotation> annotations;
3828 final Map<Class<? extends Annotation>, Annotation> declaredAnnotations;
3829
3830 // Value of classRedefinedCount when we created this AnnotationData instance
3831 final int redefinedCount;
3832
3833 AnnotationData(Map<Class<? extends Annotation>, Annotation> annotations,
3834 Map<Class<? extends Annotation>, Annotation> declaredAnnotations,
3835 int redefinedCount) {
3836 this.annotations = annotations;
3837 this.declaredAnnotations = declaredAnnotations;
3838 this.redefinedCount = redefinedCount;
3839 }
3840 }
3841
3842 // Annotations cache
3843 @SuppressWarnings("UnusedDeclaration")
3844 private transient volatile AnnotationData annotationData;
3845
3846 private AnnotationData annotationData() {
3847 while (true) { // retry loop
3848 AnnotationData annotationData = this.annotationData;
3849 int classRedefinedCount = this.classRedefinedCount;
3850 if (annotationData != null &&
3851 annotationData.redefinedCount == classRedefinedCount) {
3852 return annotationData;
3853 }
3854 // null or stale annotationData -> optimistically create new instance
3855 AnnotationData newAnnotationData = createAnnotationData(classRedefinedCount);
3856 // try to install it
3857 if (Atomic.casAnnotationData(this, annotationData, newAnnotationData)) {
3858 // successfully installed new AnnotationData
3859 return newAnnotationData;
3860 }
3861 }
3862 }
3863
3864 private AnnotationData createAnnotationData(int classRedefinedCount) {
3865 Map<Class<? extends Annotation>, Annotation> declaredAnnotations =
3866 AnnotationParser.parseAnnotations(getRawAnnotations(), getConstantPool(), this);
3867 Class<?> superClass = getSuperclass();
3868 Map<Class<? extends Annotation>, Annotation> annotations = null;
3869 if (superClass != null) {
3870 Map<Class<? extends Annotation>, Annotation> superAnnotations =
3871 superClass.annotationData().annotations;
3872 for (Map.Entry<Class<? extends Annotation>, Annotation> e : superAnnotations.entrySet()) {
3873 Class<? extends Annotation> annotationClass = e.getKey();
3874 if (AnnotationType.getInstance(annotationClass).isInherited()) {
3875 if (annotations == null) { // lazy construction
3876 annotations = new LinkedHashMap<>((Math.max(
3877 declaredAnnotations.size(),
3878 Math.min(12, declaredAnnotations.size() + superAnnotations.size())
3879 ) * 4 + 2) / 3
3880 );
3881 }
3882 annotations.put(annotationClass, e.getValue());
3883 }
3884 }
3885 }
3886 if (annotations == null) {
3887 // no inherited annotations -> share the Map with declaredAnnotations
3888 annotations = declaredAnnotations;
3889 } else {
3890 // at least one inherited annotation -> declared may override inherited
3891 annotations.putAll(declaredAnnotations);
3892 }
3893 return new AnnotationData(annotations, declaredAnnotations, classRedefinedCount);
3894 }
3895
3896 // Annotation types cache their internal (AnnotationType) form
3897
3898 @SuppressWarnings("UnusedDeclaration")
3899 private transient volatile AnnotationType annotationType;
3900
3901 boolean casAnnotationType(AnnotationType oldType, AnnotationType newType) {
3902 return Atomic.casAnnotationType(this, oldType, newType);
3903 }
3904
3905 AnnotationType getAnnotationType() {
3906 return annotationType;
3907 }
3908
3909 Map<Class<? extends Annotation>, Annotation> getDeclaredAnnotationMap() {
3910 return annotationData().declaredAnnotations;
3911 }
3912
3913 /* Backing store of user-defined values pertaining to this class.
3914 * Maintained by the ClassValue class.
3915 */
3916 transient ClassValue.ClassValueMap classValueMap;
3917
3918 /**
3919 * Returns an {@code AnnotatedType} object that represents the use of a
3920 * type to specify the superclass of the entity represented by this {@code
3921 * Class} object. (The <em>use</em> of type Foo to specify the superclass
3922 * in '... extends Foo' is distinct from the <em>declaration</em> of type
3923 * Foo.)
3924 *
3925 * <p> If this {@code Class} object represents a type whose declaration
3926 * does not explicitly indicate an annotated superclass, then the return
3927 * value is an {@code AnnotatedType} object representing an element with no
3928 * annotations.
3929 *
3930 * <p> If this {@code Class} represents either the {@code Object} class, an
3931 * interface type, an array type, a primitive type, or void, the return
3932 * value is {@code null}.
3933 *
3934 * @return an object representing the superclass
3935 * @since 1.8
3936 */
3937 public AnnotatedType getAnnotatedSuperclass() {
3938 if (this == Object.class ||
3939 isInterface() ||
3940 isArray() ||
3941 isPrimitive() ||
3942 this == Void.TYPE) {
3943 return null;
3944 }
3945
3946 return TypeAnnotationParser.buildAnnotatedSuperclass(getRawTypeAnnotations(), getConstantPool(), this);
3947 }
3948
3949 /**
3950 * Returns an array of {@code AnnotatedType} objects that represent the use
3951 * of types to specify superinterfaces of the entity represented by this
3952 * {@code Class} object. (The <em>use</em> of type Foo to specify a
3953 * superinterface in '... implements Foo' is distinct from the
3954 * <em>declaration</em> of type Foo.)
3955 *
3956 * <p> If this {@code Class} object represents a class, the return value is
3957 * an array containing objects representing the uses of interface types to
3958 * specify interfaces implemented by the class. The order of the objects in
3959 * the array corresponds to the order of the interface types used in the
3960 * 'implements' clause of the declaration of this {@code Class} object.
3961 *
3962 * <p> If this {@code Class} object represents an interface, the return
3963 * value is an array containing objects representing the uses of interface
3964 * types to specify interfaces directly extended by the interface. The
3965 * order of the objects in the array corresponds to the order of the
3966 * interface types used in the 'extends' clause of the declaration of this
3967 * {@code Class} object.
3968 *
3969 * <p> If this {@code Class} object represents a class or interface whose
3970 * declaration does not explicitly indicate any annotated superinterfaces,
3971 * the return value is an array of length 0.
3972 *
3973 * <p> If this {@code Class} object represents either the {@code Object}
3974 * class, an array type, a primitive type, or void, the return value is an
3975 * array of length 0.
3976 *
3977 * @return an array representing the superinterfaces
3978 * @since 1.8
3979 */
3980 public AnnotatedType[] getAnnotatedInterfaces() {
3981 return TypeAnnotationParser.buildAnnotatedInterfaces(getRawTypeAnnotations(), getConstantPool(), this);
3982 }
3983
3984 private native Class<?> getNestHost0();
3985
3986 /**
3987 * Returns the nest host of the <a href=#nest>nest</a> to which the class
3988 * or interface represented by this {@code Class} object belongs.
3989 * Every class and interface is a member of exactly one nest.
3990 * A class or interface that is not recorded as belonging to a nest
3991 * belongs to the nest consisting only of itself, and is the nest
3992 * host.
3993 *
3994 * <p>Each of the {@code Class} objects representing array types,
3995 * primitive types, and {@code void} returns {@code this} to indicate
3996 * that the represented entity belongs to the nest consisting only of
3997 * itself, and is the nest host.
3998 *
3999 * <p>If there is a {@linkplain LinkageError linkage error} accessing
4000 * the nest host, or if this class or interface is not enumerated as
4001 * a member of the nest by the nest host, then it is considered to belong
4002 * to its own nest and {@code this} is returned as the host.
4003 *
4004 * @apiNote A {@code class} file of version 55.0 or greater may record the
4005 * host of the nest to which it belongs by using the {@code NestHost}
4006 * attribute (JVMS 4.7.28). Alternatively, a {@code class} file of
4007 * version 55.0 or greater may act as a nest host by enumerating the nest's
4008 * other members with the
4009 * {@code NestMembers} attribute (JVMS 4.7.29).
4010 * A {@code class} file of version 54.0 or lower does not use these
4011 * attributes.
4012 *
4013 * @return the nest host of this class or interface
4014 *
4015 * @throws SecurityException
4016 * If the returned class is not the current class, and
4017 * if a security manager, <i>s</i>, is present and the caller's
4018 * class loader is not the same as or an ancestor of the class
4019 * loader for the returned class and invocation of {@link
4020 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
4021 * denies access to the package of the returned class
4022 * @since 11
4023 * @jvms 4.7.28 The {@code NestHost} Attribute
4024 * @jvms 4.7.29 The {@code NestMembers} Attribute
4025 * @jvms 5.4.4 Access Control
4026 */
4027 @CallerSensitive
4028 public Class<?> getNestHost() {
4029 if (isPrimitive() || isArray()) {
4030 return this;
4031 }
4032 Class<?> host;
4033 try {
4034 host = getNestHost0();
4035 } catch (LinkageError e) {
4036 // if we couldn't load our nest-host then we
4037 // act as-if we have no nest-host attribute
4038 return this;
4039 }
4040 // if null then nest membership validation failed, so we
4041 // act as-if we have no nest-host attribute
4042 if (host == null || host == this) {
4043 return this;
4044 }
4045 // returning a different class requires a security check
4046 SecurityManager sm = System.getSecurityManager();
4047 if (sm != null) {
4048 checkPackageAccess(sm,
4049 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
4050 }
4051 return host;
4052 }
4053
4054 /**
4055 * Determines if the given {@code Class} is a nestmate of the
4056 * class or interface represented by this {@code Class} object.
4057 * Two classes or interfaces are nestmates
4058 * if they have the same {@linkplain #getNestHost() nest host}.
4059 *
4060 * @param c the class to check
4061 * @return {@code true} if this class and {@code c} are members of
4062 * the same nest; and {@code false} otherwise.
4063 *
4064 * @since 11
4065 */
4066 public boolean isNestmateOf(Class<?> c) {
4067 if (this == c) {
4068 return true;
4069 }
4070 if (isPrimitive() || isArray() ||
4071 c.isPrimitive() || c.isArray()) {
4072 return false;
4073 }
4074 try {
4075 return getNestHost0() == c.getNestHost0();
4076 } catch (LinkageError e) {
4077 return false;
4078 }
4079 }
4080
4081 private native Class<?>[] getNestMembers0();
4082
4083 /**
4084 * Returns an array containing {@code Class} objects representing all the
4085 * classes and interfaces that are members of the nest to which the class
4086 * or interface represented by this {@code Class} object belongs.
4087 * The {@linkplain #getNestHost() nest host} of that nest is the zeroth
4088 * element of the array. Subsequent elements represent any classes or
4089 * interfaces that are recorded by the nest host as being members of
4090 * the nest; the order of such elements is unspecified. Duplicates are
4091 * permitted.
4092 * If the nest host of that nest does not enumerate any members, then the
4093 * array has a single element containing {@code this}.
4094 *
4095 * <p>Each of the {@code Class} objects representing array types,
4096 * primitive types, and {@code void} returns an array containing only
4097 * {@code this}.
4098 *
4099 * <p>This method validates that, for each class or interface which is
4100 * recorded as a member of the nest by the nest host, that class or
4101 * interface records itself as a member of that same nest. Any exceptions
4102 * that occur during this validation are rethrown by this method.
4103 *
4104 * @return an array of all classes and interfaces in the same nest as
4105 * this class
4106 *
4107 * @throws LinkageError
4108 * If there is any problem loading or validating a nest member or
4109 * its nest host
4110 * @throws SecurityException
4111 * If any returned class is not the current class, and
4112 * if a security manager, <i>s</i>, is present and the caller's
4113 * class loader is not the same as or an ancestor of the class
4114 * loader for that returned class and invocation of {@link
4115 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
4116 * denies access to the package of that returned class
4117 *
4118 * @since 11
4119 * @see #getNestHost()
4120 */
4121 @CallerSensitive
4122 public Class<?>[] getNestMembers() {
4123 if (isPrimitive() || isArray()) {
4124 return new Class<?>[] { this };
4125 }
4126 Class<?>[] members = getNestMembers0();
4127 // Can't actually enable this due to bootstrapping issues
4128 // assert(members.length != 1 || members[0] == this); // expected invariant from VM
4129
4130 if (members.length > 1) {
4131 // If we return anything other than the current class we need
4132 // a security check
4133 SecurityManager sm = System.getSecurityManager();
4134 if (sm != null) {
4135 checkPackageAccess(sm,
4136 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
4137 }
4138 }
4139 return members;
4140 }
4141
4142 /**
4143 * Returns the type descriptor string for this class.
4144 * <p>
4145 * Note that this is not a strict inverse of {@link #forName};
4146 * distinct classes which share a common name but have different class loaders
4147 * will have identical descriptor strings.
4148 *
4149 * @return the type descriptor representation
4150 * @jvms 4.3.2 Field Descriptors
4151 * @since 12
4152 */
4153 @Override
4154 public String descriptorString() {
4155 if (isPrimitive())
4156 return Wrapper.forPrimitiveType(this).basicTypeString();
4157 else if (isArray()) {
4158 return "[" + componentType.descriptorString();
4159 }
4160 else {
4161 return "L" + getName().replace('.', '/') + ";";
4162 }
4163 }
4164
4165 /**
4166 * Returns the component type of this {@code Class}, if it describes
4167 * an array type, or {@code null} otherwise.
4168 *
4169 * @implSpec
4170 * Equivalent to {@link Class#getComponentType()}.
4171 *
4172 * @return a {@code Class} describing the component type, or {@code null}
4173 * if this {@code Class} does not describe an array type
4174 * @since 12
4175 */
4176 @Override
4177 public Class<?> componentType() {
4178 return isArray() ? componentType : null;
4179 }
4180
4181 /**
4182 * Returns a {@code Class} for an array type whose component type
4183 * is described by this {@linkplain Class}.
4184 *
4185 * @return a {@code Class} describing the array type
4186 * @since 12
4187 */
4188 @Override
4189 public Class<?> arrayType() {
4190 return Array.newInstance(this, 0).getClass();
4191 }
4192
4193 /**
4194 * Returns a nominal descriptor for this instance, if one can be
4195 * constructed, or an empty {@link Optional} if one cannot be.
4196 *
4197 * @return An {@link Optional} containing the resulting nominal descriptor,
4198 * or an empty {@link Optional} if one cannot be constructed.
4199 * @since 12
4200 */
4201 @Override
4202 public Optional<ClassDesc> describeConstable() {
4203 return Optional.of(ClassDesc.ofDescriptor(descriptorString()));
4204 }
4205 }