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},
211 * <code>@</code>{@code interface}, or {@code record} 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 @SuppressWarnings("preview")
238 public String toGenericString() {
239 if (isPrimitive()) {
240 return toString();
241 } else {
242 StringBuilder sb = new StringBuilder();
243 Class<?> component = this;
244 int arrayDepth = 0;
245
246 if (isArray()) {
247 do {
248 arrayDepth++;
249 component = component.getComponentType();
250 } while (component.isArray());
251 sb.append(component.getName());
252 } else {
253 // Class modifiers are a superset of interface modifiers
254 int modifiers = getModifiers() & Modifier.classModifiers();
255 if (modifiers != 0) {
256 sb.append(Modifier.toString(modifiers));
257 sb.append(' ');
258 }
259
260 if (isAnnotation()) {
261 sb.append('@');
262 }
263 if (isInterface()) { // Note: all annotation types are interfaces
264 sb.append("interface");
265 } else {
266 if (isEnum())
267 sb.append("enum");
268 else if (isRecord())
269 sb.append("record");
270 else
271 sb.append("class");
272 }
273 sb.append(' ');
274 sb.append(getName());
275 }
276
277 TypeVariable<?>[] typeparms = component.getTypeParameters();
278 if (typeparms.length > 0) {
279 sb.append(Arrays.stream(typeparms)
280 .map(Class::typeVarBounds)
281 .collect(Collectors.joining(",", "<", ">")));
282 }
283
284 if (arrayDepth > 0) sb.append("[]".repeat(arrayDepth));
285
286 return sb.toString();
287 }
288 }
289
290 static String typeVarBounds(TypeVariable<?> typeVar) {
291 Type[] bounds = typeVar.getBounds();
292 if (bounds.length == 1 && bounds[0].equals(Object.class)) {
293 return typeVar.getName();
294 } else {
295 return typeVar.getName() + " extends " +
296 Arrays.stream(bounds)
297 .map(Type::getTypeName)
298 .collect(Collectors.joining(" & "));
299 }
300 }
301
302 /**
303 * Returns the {@code Class} object associated with the class or
304 * interface with the given string name. Invoking this method is
305 * equivalent to:
306 *
307 * <blockquote>
308 * {@code Class.forName(className, true, currentLoader)}
309 * </blockquote>
310 *
311 * where {@code currentLoader} denotes the defining class loader of
312 * the current class.
313 *
314 * <p> For example, the following code fragment returns the
315 * runtime {@code Class} descriptor for the class named
316 * {@code java.lang.Thread}:
317 *
318 * <blockquote>
319 * {@code Class t = Class.forName("java.lang.Thread")}
320 * </blockquote>
321 * <p>
322 * A call to {@code forName("X")} causes the class named
323 * {@code X} to be initialized.
324 *
325 * @param className the fully qualified name of the desired class.
326 * @return the {@code Class} object for the class with the
327 * specified name.
328 * @throws LinkageError if the linkage fails
329 * @throws ExceptionInInitializerError if the initialization provoked
330 * by this method fails
331 * @throws ClassNotFoundException if the class cannot be located
332 *
333 * @jls 12.2 Loading of Classes and Interfaces
334 * @jls 12.3 Linking of Classes and Interfaces
335 * @jls 12.4 Initialization of Classes and Interfaces
336 */
337 @CallerSensitive
338 public static Class<?> forName(String className)
339 throws ClassNotFoundException {
340 Class<?> caller = Reflection.getCallerClass();
341 return forName0(className, true, ClassLoader.getClassLoader(caller), caller);
342 }
343
344
345 /**
346 * Returns the {@code Class} object associated with the class or
347 * interface with the given string name, using the given class loader.
348 * Given the fully qualified name for a class or interface (in the same
349 * format returned by {@code getName}) this method attempts to
350 * locate and load the class or interface. The specified class
351 * loader is used to load the class or interface. If the parameter
352 * {@code loader} is null, the class is loaded through the bootstrap
353 * class loader. The class is initialized only if the
354 * {@code initialize} parameter is {@code true} and if it has
355 * not been initialized earlier.
356 *
357 * <p> If {@code name} denotes a primitive type or void, an attempt
358 * will be made to locate a user-defined class in the unnamed package whose
359 * name is {@code name}. Therefore, this method cannot be used to
360 * obtain any of the {@code Class} objects representing primitive
361 * types or void.
362 *
363 * <p> If {@code name} denotes an array class, the component type of
364 * the array class is loaded but not initialized.
365 *
366 * <p> For example, in an instance method the expression:
367 *
368 * <blockquote>
369 * {@code Class.forName("Foo")}
370 * </blockquote>
371 *
372 * is equivalent to:
373 *
374 * <blockquote>
375 * {@code Class.forName("Foo", true, this.getClass().getClassLoader())}
376 * </blockquote>
377 *
378 * Note that this method throws errors related to loading, linking or
379 * initializing as specified in Sections 12.2, 12.3 and 12.4 of <em>The
380 * Java Language Specification</em>.
381 * Note that this method does not check whether the requested class
382 * is accessible to its caller.
383 *
384 * @param name fully qualified name of the desired class
385 * @param initialize if {@code true} the class will be initialized (which implies linking).
386 * See Section 12.4 of <em>The Java Language Specification</em>.
387 * @param loader class loader from which the class must be loaded
388 * @return class object representing the desired class
389 *
390 * @throws LinkageError if the linkage fails
391 * @throws ExceptionInInitializerError if the initialization provoked
392 * by this method fails
393 * @throws ClassNotFoundException if the class cannot be located by
394 * the specified class loader
395 * @throws SecurityException
396 * if a security manager is present, and the {@code loader} is
397 * {@code null}, and the caller's class loader is not
398 * {@code null}, and the caller does not have the
399 * {@link RuntimePermission}{@code ("getClassLoader")}
400 *
401 * @see java.lang.Class#forName(String)
402 * @see java.lang.ClassLoader
403 *
404 * @jls 12.2 Loading of Classes and Interfaces
405 * @jls 12.3 Linking of Classes and Interfaces
406 * @jls 12.4 Initialization of Classes and Interfaces
407 * @since 1.2
408 */
409 @CallerSensitive
410 public static Class<?> forName(String name, boolean initialize,
411 ClassLoader loader)
412 throws ClassNotFoundException
413 {
414 Class<?> caller = null;
415 SecurityManager sm = System.getSecurityManager();
416 if (sm != null) {
417 // Reflective call to get caller class is only needed if a security manager
418 // is present. Avoid the overhead of making this call otherwise.
419 caller = Reflection.getCallerClass();
420 if (loader == null) {
421 ClassLoader ccl = ClassLoader.getClassLoader(caller);
422 if (ccl != null) {
423 sm.checkPermission(
424 SecurityConstants.GET_CLASSLOADER_PERMISSION);
425 }
426 }
427 }
428 return forName0(name, initialize, loader, caller);
429 }
430
431 /** Called after security check for system loader access checks have been made. */
432 private static native Class<?> forName0(String name, boolean initialize,
433 ClassLoader loader,
434 Class<?> caller)
435 throws ClassNotFoundException;
436
437
438 /**
439 * Returns the {@code Class} with the given <a href="ClassLoader.html#binary-name">
440 * binary name</a> in the given module.
441 *
442 * <p> This method attempts to locate and load the class or interface.
443 * It does not link the class, and does not run the class initializer.
444 * If the class is not found, this method returns {@code null}. </p>
445 *
446 * <p> If the class loader of the given module defines other modules and
447 * the given name is a class defined in a different module, this method
448 * returns {@code null} after the class is loaded. </p>
449 *
450 * <p> This method does not check whether the requested class is
451 * accessible to its caller. </p>
452 *
453 * @apiNote
454 * This method returns {@code null} on failure rather than
455 * throwing a {@link ClassNotFoundException}, as is done by
456 * the {@link #forName(String, boolean, ClassLoader)} method.
457 * The security check is a stack-based permission check if the caller
458 * loads a class in another module.
459 *
460 * @param module A module
461 * @param name The <a href="ClassLoader.html#binary-name">binary name</a>
462 * of the class
463 * @return {@code Class} object of the given name defined in the given module;
464 * {@code null} if not found.
465 *
466 * @throws NullPointerException if the given module or name is {@code null}
467 *
468 * @throws LinkageError if the linkage fails
469 *
470 * @throws SecurityException
471 * <ul>
472 * <li> if the caller is not the specified module and
473 * {@code RuntimePermission("getClassLoader")} permission is denied; or</li>
474 * <li> access to the module content is denied. For example,
475 * permission check will be performed when a class loader calls
476 * {@link ModuleReader#open(String)} to read the bytes of a class file
477 * in a module.</li>
478 * </ul>
479 *
480 * @jls 12.2 Loading of Classes and Interfaces
481 * @jls 12.3 Linking of Classes and Interfaces
482 * @since 9
483 * @spec JPMS
484 */
485 @CallerSensitive
486 public static Class<?> forName(Module module, String name) {
487 Objects.requireNonNull(module);
488 Objects.requireNonNull(name);
489
490 ClassLoader cl;
491 SecurityManager sm = System.getSecurityManager();
492 if (sm != null) {
493 Class<?> caller = Reflection.getCallerClass();
494 if (caller != null && caller.getModule() != module) {
495 // if caller is null, Class.forName is the last java frame on the stack.
496 // java.base has all permissions
497 sm.checkPermission(SecurityConstants.GET_CLASSLOADER_PERMISSION);
498 }
499 PrivilegedAction<ClassLoader> pa = module::getClassLoader;
500 cl = AccessController.doPrivileged(pa);
501 } else {
502 cl = module.getClassLoader();
503 }
504
505 if (cl != null) {
506 return cl.loadClass(module, name);
507 } else {
508 return BootLoader.loadClass(module, name);
509 }
510 }
511
512 /**
513 * Creates a new instance of the class represented by this {@code Class}
514 * object. The class is instantiated as if by a {@code new}
515 * expression with an empty argument list. The class is initialized if it
516 * has not already been initialized.
517 *
518 * @deprecated This method propagates any exception thrown by the
519 * nullary constructor, including a checked exception. Use of
520 * this method effectively bypasses the compile-time exception
521 * checking that would otherwise be performed by the compiler.
522 * The {@link
523 * java.lang.reflect.Constructor#newInstance(java.lang.Object...)
524 * Constructor.newInstance} method avoids this problem by wrapping
525 * any exception thrown by the constructor in a (checked) {@link
526 * java.lang.reflect.InvocationTargetException}.
527 *
528 * <p>The call
529 *
530 * <pre>{@code
531 * clazz.newInstance()
532 * }</pre>
533 *
534 * can be replaced by
535 *
536 * <pre>{@code
537 * clazz.getDeclaredConstructor().newInstance()
538 * }</pre>
539 *
540 * The latter sequence of calls is inferred to be able to throw
541 * the additional exception types {@link
542 * InvocationTargetException} and {@link
543 * NoSuchMethodException}. Both of these exception types are
544 * subclasses of {@link ReflectiveOperationException}.
545 *
546 * @return a newly allocated instance of the class represented by this
547 * object.
548 * @throws IllegalAccessException if the class or its nullary
549 * constructor is not accessible.
550 * @throws InstantiationException
551 * if this {@code Class} represents an abstract class,
552 * an interface, an array class, a primitive type, or void;
553 * or if the class has no nullary constructor;
554 * or if the instantiation fails for some other reason.
555 * @throws ExceptionInInitializerError if the initialization
556 * provoked by this method fails.
557 * @throws SecurityException
558 * If a security manager, <i>s</i>, is present and
559 * the caller's class loader is not the same as or an
560 * ancestor of the class loader for the current class and
561 * invocation of {@link SecurityManager#checkPackageAccess
562 * s.checkPackageAccess()} denies access to the package
563 * of this class.
564 */
565 @CallerSensitive
566 @Deprecated(since="9")
567 public T newInstance()
568 throws InstantiationException, IllegalAccessException
569 {
570 SecurityManager sm = System.getSecurityManager();
571 if (sm != null) {
572 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), false);
573 }
574
575 // Constructor lookup
576 Constructor<T> tmpConstructor = cachedConstructor;
577 if (tmpConstructor == null) {
578 if (this == Class.class) {
579 throw new IllegalAccessException(
580 "Can not call newInstance() on the Class for java.lang.Class"
581 );
582 }
583 try {
584 Class<?>[] empty = {};
585 final Constructor<T> c = getReflectionFactory().copyConstructor(
586 getConstructor0(empty, Member.DECLARED));
587 // Disable accessibility checks on the constructor
588 // access check is done with the true caller
589 java.security.AccessController.doPrivileged(
590 new java.security.PrivilegedAction<>() {
591 public Void run() {
592 c.setAccessible(true);
593 return null;
594 }
595 });
596 cachedConstructor = tmpConstructor = c;
597 } catch (NoSuchMethodException e) {
598 throw (InstantiationException)
599 new InstantiationException(getName()).initCause(e);
600 }
601 }
602
603 try {
604 Class<?> caller = Reflection.getCallerClass();
605 return getReflectionFactory().newInstance(tmpConstructor, null, caller);
606 } catch (InvocationTargetException e) {
607 Unsafe.getUnsafe().throwException(e.getTargetException());
608 // Not reached
609 return null;
610 }
611 }
612
613 private transient volatile Constructor<T> cachedConstructor;
614
615 /**
616 * Determines if the specified {@code Object} is assignment-compatible
617 * with the object represented by this {@code Class}. This method is
618 * the dynamic equivalent of the Java language {@code instanceof}
619 * operator. The method returns {@code true} if the specified
620 * {@code Object} argument is non-null and can be cast to the
621 * reference type represented by this {@code Class} object without
622 * raising a {@code ClassCastException.} It returns {@code false}
623 * otherwise.
624 *
625 * <p> Specifically, if this {@code Class} object represents a
626 * declared class, this method returns {@code true} if the specified
627 * {@code Object} argument is an instance of the represented class (or
628 * of any of its subclasses); it returns {@code false} otherwise. If
629 * this {@code Class} object represents an array class, this method
630 * returns {@code true} if the specified {@code Object} argument
631 * can be converted to an object of the array class by an identity
632 * conversion or by a widening reference conversion; it returns
633 * {@code false} otherwise. If this {@code Class} object
634 * represents an interface, this method returns {@code true} if the
635 * class or any superclass of the specified {@code Object} argument
636 * implements this interface; it returns {@code false} otherwise. If
637 * this {@code Class} object represents a primitive type, this method
638 * returns {@code false}.
639 *
640 * @param obj the object to check
641 * @return true if {@code obj} is an instance of this class
642 *
643 * @since 1.1
644 */
645 @HotSpotIntrinsicCandidate
646 public native boolean isInstance(Object obj);
647
648
649 /**
650 * Determines if the class or interface represented by this
651 * {@code Class} object is either the same as, or is a superclass or
652 * superinterface of, the class or interface represented by the specified
653 * {@code Class} parameter. It returns {@code true} if so;
654 * otherwise it returns {@code false}. If this {@code Class}
655 * object represents a primitive type, this method returns
656 * {@code true} if the specified {@code Class} parameter is
657 * exactly this {@code Class} object; otherwise it returns
658 * {@code false}.
659 *
660 * <p> Specifically, this method tests whether the type represented by the
661 * specified {@code Class} parameter can be converted to the type
662 * represented by this {@code Class} object via an identity conversion
663 * or via a widening reference conversion. See <em>The Java Language
664 * Specification</em>, sections 5.1.1 and 5.1.4 , for details.
665 *
666 * @param cls the {@code Class} object to be checked
667 * @return the {@code boolean} value indicating whether objects of the
668 * type {@code cls} can be assigned to objects of this class
669 * @throws NullPointerException if the specified Class parameter is
670 * null.
671 * @since 1.1
672 */
673 @HotSpotIntrinsicCandidate
674 public native boolean isAssignableFrom(Class<?> cls);
675
676
677 /**
678 * Determines if the specified {@code Class} object represents an
679 * interface type.
680 *
681 * @return {@code true} if this object represents an interface;
682 * {@code false} otherwise.
683 */
684 @HotSpotIntrinsicCandidate
685 public native boolean isInterface();
686
687
688 /**
689 * Determines if this {@code Class} object represents an array class.
690 *
691 * @return {@code true} if this object represents an array class;
692 * {@code false} otherwise.
693 * @since 1.1
694 */
695 @HotSpotIntrinsicCandidate
696 public native boolean isArray();
697
698
699 /**
700 * Determines if the specified {@code Class} object represents a
701 * primitive type.
702 *
703 * <p> There are nine predefined {@code Class} objects to represent
704 * the eight primitive types and void. These are created by the Java
705 * Virtual Machine, and have the same names as the primitive types that
706 * they represent, namely {@code boolean}, {@code byte},
707 * {@code char}, {@code short}, {@code int},
708 * {@code long}, {@code float}, and {@code double}.
709 *
710 * <p> These objects may only be accessed via the following public static
711 * final variables, and are the only {@code Class} objects for which
712 * this method returns {@code true}.
713 *
714 * @return true if and only if this class represents a primitive type
715 *
716 * @see java.lang.Boolean#TYPE
717 * @see java.lang.Character#TYPE
718 * @see java.lang.Byte#TYPE
719 * @see java.lang.Short#TYPE
720 * @see java.lang.Integer#TYPE
721 * @see java.lang.Long#TYPE
722 * @see java.lang.Float#TYPE
723 * @see java.lang.Double#TYPE
724 * @see java.lang.Void#TYPE
725 * @since 1.1
726 */
727 @HotSpotIntrinsicCandidate
728 public native boolean isPrimitive();
729
730 /**
731 * Returns true if this {@code Class} object represents an annotation
732 * type. Note that if this method returns true, {@link #isInterface()}
733 * would also return true, as all annotation types are also interfaces.
734 *
735 * @return {@code true} if this class object represents an annotation
736 * type; {@code false} otherwise
737 * @since 1.5
738 */
739 public boolean isAnnotation() {
740 return (getModifiers() & ANNOTATION) != 0;
741 }
742
743 /**
744 * Returns {@code true} if this class is a synthetic class;
745 * returns {@code false} otherwise.
746 * @return {@code true} if and only if this class is a synthetic class as
747 * defined by the Java Language Specification.
748 * @jls 13.1 The Form of a Binary
749 * @since 1.5
750 */
751 public boolean isSynthetic() {
752 return (getModifiers() & SYNTHETIC) != 0;
753 }
754
755 /**
756 * Returns the name of the entity (class, interface, array class,
757 * primitive type, or void) represented by this {@code Class} object,
758 * as a {@code String}.
759 *
760 * <p> If this class object represents a reference type that is not an
761 * array type then the binary name of the class is returned, as specified
762 * by
763 * <cite>The Java™ Language Specification</cite>.
764 *
765 * <p> If this class object represents a primitive type or void, then the
766 * name returned is a {@code String} equal to the Java language
767 * keyword corresponding to the primitive type or void.
768 *
769 * <p> If this class object represents a class of arrays, then the internal
770 * form of the name consists of the name of the element type preceded by
771 * one or more '{@code [}' characters representing the depth of the array
772 * nesting. The encoding of element type names is as follows:
773 *
774 * <blockquote><table class="striped">
775 * <caption style="display:none">Element types and encodings</caption>
776 * <thead>
777 * <tr><th scope="col"> Element Type <th scope="col"> Encoding
778 * </thead>
779 * <tbody style="text-align:left">
780 * <tr><th scope="row"> boolean <td style="text-align:center"> Z
781 * <tr><th scope="row"> byte <td style="text-align:center"> B
782 * <tr><th scope="row"> char <td style="text-align:center"> C
783 * <tr><th scope="row"> class or interface
784 * <td style="text-align:center"> L<i>classname</i>;
785 * <tr><th scope="row"> double <td style="text-align:center"> D
786 * <tr><th scope="row"> float <td style="text-align:center"> F
787 * <tr><th scope="row"> int <td style="text-align:center"> I
788 * <tr><th scope="row"> long <td style="text-align:center"> J
789 * <tr><th scope="row"> short <td style="text-align:center"> S
790 * </tbody>
791 * </table></blockquote>
792 *
793 * <p> The class or interface name <i>classname</i> is the binary name of
794 * the class specified above.
795 *
796 * <p> Examples:
797 * <blockquote><pre>
798 * String.class.getName()
799 * returns "java.lang.String"
800 * byte.class.getName()
801 * returns "byte"
802 * (new Object[3]).getClass().getName()
803 * returns "[Ljava.lang.Object;"
804 * (new int[3][4][5][6][7][8][9]).getClass().getName()
805 * returns "[[[[[[[I"
806 * </pre></blockquote>
807 *
808 * @return the name of the class or interface
809 * represented by this object.
810 */
811 public String getName() {
812 String name = this.name;
813 return name != null ? name : initClassName();
814 }
815
816 // Cache the name to reduce the number of calls into the VM.
817 // This field would be set by VM itself during initClassName call.
818 private transient String name;
819 private native String initClassName();
820
821 /**
822 * Returns the class loader for the class. Some implementations may use
823 * null to represent the bootstrap class loader. This method will return
824 * null in such implementations if this class was loaded by the bootstrap
825 * class loader.
826 *
827 * <p>If this object
828 * represents a primitive type or void, null is returned.
829 *
830 * @return the class loader that loaded the class or interface
831 * represented by this object.
832 * @throws SecurityException
833 * if a security manager is present, and the caller's class loader
834 * is not {@code null} and is not the same as or an ancestor of the
835 * class loader for the class whose class loader is requested,
836 * and the caller does not have the
837 * {@link RuntimePermission}{@code ("getClassLoader")}
838 * @see java.lang.ClassLoader
839 * @see SecurityManager#checkPermission
840 * @see java.lang.RuntimePermission
841 */
842 @CallerSensitive
843 @ForceInline // to ensure Reflection.getCallerClass optimization
844 public ClassLoader getClassLoader() {
845 ClassLoader cl = getClassLoader0();
846 if (cl == null)
847 return null;
848 SecurityManager sm = System.getSecurityManager();
849 if (sm != null) {
850 ClassLoader.checkClassLoaderPermission(cl, Reflection.getCallerClass());
851 }
852 return cl;
853 }
854
855 // Package-private to allow ClassLoader access
856 ClassLoader getClassLoader0() { return classLoader; }
857
858 /**
859 * Returns the module that this class or interface is a member of.
860 *
861 * If this class represents an array type then this method returns the
862 * {@code Module} for the element type. If this class represents a
863 * primitive type or void, then the {@code Module} object for the
864 * {@code java.base} module is returned.
865 *
866 * If this class is in an unnamed module then the {@linkplain
867 * ClassLoader#getUnnamedModule() unnamed} {@code Module} of the class
868 * loader for this class is returned.
869 *
870 * @return the module that this class or interface is a member of
871 *
872 * @since 9
873 * @spec JPMS
874 */
875 public Module getModule() {
876 return module;
877 }
878
879 // set by VM
880 private transient Module module;
881
882 // Initialized in JVM not by private constructor
883 // This field is filtered from reflection access, i.e. getDeclaredField
884 // will throw NoSuchFieldException
885 private final ClassLoader classLoader;
886
887 /**
888 * Returns an array of {@code TypeVariable} objects that represent the
889 * type variables declared by the generic declaration represented by this
890 * {@code GenericDeclaration} object, in declaration order. Returns an
891 * array of length 0 if the underlying generic declaration declares no type
892 * variables.
893 *
894 * @return an array of {@code TypeVariable} objects that represent
895 * the type variables declared by this generic declaration
896 * @throws java.lang.reflect.GenericSignatureFormatError if the generic
897 * signature of this generic declaration does not conform to
898 * the format specified in
899 * <cite>The Java™ Virtual Machine Specification</cite>
900 * @since 1.5
901 */
902 @SuppressWarnings("unchecked")
903 public TypeVariable<Class<T>>[] getTypeParameters() {
904 ClassRepository info = getGenericInfo();
905 if (info != null)
906 return (TypeVariable<Class<T>>[])info.getTypeParameters();
907 else
908 return (TypeVariable<Class<T>>[])new TypeVariable<?>[0];
909 }
910
911
912 /**
913 * Returns the {@code Class} representing the direct superclass of the
914 * entity (class, interface, primitive type or void) represented by
915 * this {@code Class}. If this {@code Class} represents either the
916 * {@code Object} class, an interface, a primitive type, or void, then
917 * null is returned. If this object represents an array class then the
918 * {@code Class} object representing the {@code Object} class is
919 * returned.
920 *
921 * @return the direct superclass of the class represented by this object
922 */
923 @HotSpotIntrinsicCandidate
924 public native Class<? super T> getSuperclass();
925
926
927 /**
928 * Returns the {@code Type} representing the direct superclass of
929 * the entity (class, interface, primitive type or void) represented by
930 * this {@code Class}.
931 *
932 * <p>If the superclass is a parameterized type, the {@code Type}
933 * object returned must accurately reflect the actual type
934 * arguments used in the source code. The parameterized type
935 * representing the superclass is created if it had not been
936 * created before. See the declaration of {@link
937 * java.lang.reflect.ParameterizedType ParameterizedType} for the
938 * semantics of the creation process for parameterized types. If
939 * this {@code Class} represents either the {@code Object}
940 * class, an interface, a primitive type, or void, then null is
941 * returned. If this object represents an array class then the
942 * {@code Class} object representing the {@code Object} class is
943 * returned.
944 *
945 * @throws java.lang.reflect.GenericSignatureFormatError if the generic
946 * class signature does not conform to the format specified in
947 * <cite>The Java™ Virtual Machine Specification</cite>
948 * @throws TypeNotPresentException if the generic superclass
949 * refers to a non-existent type declaration
950 * @throws java.lang.reflect.MalformedParameterizedTypeException if the
951 * generic superclass refers to a parameterized type that cannot be
952 * instantiated for any reason
953 * @return the direct superclass of the class represented by this object
954 * @since 1.5
955 */
956 public Type getGenericSuperclass() {
957 ClassRepository info = getGenericInfo();
958 if (info == null) {
959 return getSuperclass();
960 }
961
962 // Historical irregularity:
963 // Generic signature marks interfaces with superclass = Object
964 // but this API returns null for interfaces
965 if (isInterface()) {
966 return null;
967 }
968
969 return info.getSuperclass();
970 }
971
972 /**
973 * Gets the package of this class.
974 *
975 * <p>If this class represents an array type, a primitive type or void,
976 * this method returns {@code null}.
977 *
978 * @return the package of this class.
979 * @revised 9
980 * @spec JPMS
981 */
982 public Package getPackage() {
983 if (isPrimitive() || isArray()) {
984 return null;
985 }
986 ClassLoader cl = getClassLoader0();
987 return cl != null ? cl.definePackage(this)
988 : BootLoader.definePackage(this);
989 }
990
991 /**
992 * Returns the fully qualified package name.
993 *
994 * <p> If this class is a top level class, then this method returns the fully
995 * qualified name of the package that the class is a member of, or the
996 * empty string if the class is in an unnamed package.
997 *
998 * <p> If this class is a member class, then this method is equivalent to
999 * invoking {@code getPackageName()} on the {@linkplain #getEnclosingClass
1000 * enclosing class}.
1001 *
1002 * <p> If this class is a {@linkplain #isLocalClass local class} or an {@linkplain
1003 * #isAnonymousClass() anonymous class}, then this method is equivalent to
1004 * invoking {@code getPackageName()} on the {@linkplain #getDeclaringClass
1005 * declaring class} of the {@linkplain #getEnclosingMethod enclosing method} or
1006 * {@linkplain #getEnclosingConstructor enclosing constructor}.
1007 *
1008 * <p> If this class represents an array type then this method returns the
1009 * package name of the element type. If this class represents a primitive
1010 * type or void then the package name "{@code java.lang}" is returned.
1011 *
1012 * @return the fully qualified package name
1013 *
1014 * @since 9
1015 * @spec JPMS
1016 * @jls 6.7 Fully Qualified Names
1017 */
1018 public String getPackageName() {
1019 String pn = this.packageName;
1020 if (pn == null) {
1021 Class<?> c = this;
1022 while (c.isArray()) {
1023 c = c.getComponentType();
1024 }
1025 if (c.isPrimitive()) {
1026 pn = "java.lang";
1027 } else {
1028 String cn = c.getName();
1029 int dot = cn.lastIndexOf('.');
1030 pn = (dot != -1) ? cn.substring(0, dot).intern() : "";
1031 }
1032 this.packageName = pn;
1033 }
1034 return pn;
1035 }
1036
1037 // cached package name
1038 private transient String packageName;
1039
1040 /**
1041 * Returns the interfaces directly implemented by the class or interface
1042 * represented by this object.
1043 *
1044 * <p>If this object represents a class, the return value is an array
1045 * containing objects representing all interfaces directly implemented by
1046 * the class. The order of the interface objects in the array corresponds
1047 * to the order of the interface names in the {@code implements} clause of
1048 * the declaration of the class represented by this object. For example,
1049 * given the declaration:
1050 * <blockquote>
1051 * {@code class Shimmer implements FloorWax, DessertTopping { ... }}
1052 * </blockquote>
1053 * suppose the value of {@code s} is an instance of
1054 * {@code Shimmer}; the value of the expression:
1055 * <blockquote>
1056 * {@code s.getClass().getInterfaces()[0]}
1057 * </blockquote>
1058 * is the {@code Class} object that represents interface
1059 * {@code FloorWax}; and the value of:
1060 * <blockquote>
1061 * {@code s.getClass().getInterfaces()[1]}
1062 * </blockquote>
1063 * is the {@code Class} object that represents interface
1064 * {@code DessertTopping}.
1065 *
1066 * <p>If this object represents an interface, the array contains objects
1067 * representing all interfaces directly extended by the interface. The
1068 * order of the interface objects in the array corresponds to the order of
1069 * the interface names in the {@code extends} clause of the declaration of
1070 * the interface represented by this object.
1071 *
1072 * <p>If this object represents a class or interface that implements no
1073 * interfaces, the method returns an array of length 0.
1074 *
1075 * <p>If this object represents a primitive type or void, the method
1076 * returns an array of length 0.
1077 *
1078 * <p>If this {@code Class} object represents an array type, the
1079 * interfaces {@code Cloneable} and {@code java.io.Serializable} are
1080 * returned in that order.
1081 *
1082 * @return an array of interfaces directly implemented by this class
1083 */
1084 public Class<?>[] getInterfaces() {
1085 // defensively copy before handing over to user code
1086 return getInterfaces(true);
1087 }
1088
1089 private Class<?>[] getInterfaces(boolean cloneArray) {
1090 ReflectionData<T> rd = reflectionData();
1091 if (rd == null) {
1092 // no cloning required
1093 return getInterfaces0();
1094 } else {
1095 Class<?>[] interfaces = rd.interfaces;
1096 if (interfaces == null) {
1097 interfaces = getInterfaces0();
1098 rd.interfaces = interfaces;
1099 }
1100 // defensively copy if requested
1101 return cloneArray ? interfaces.clone() : interfaces;
1102 }
1103 }
1104
1105 private native Class<?>[] getInterfaces0();
1106
1107 /**
1108 * Returns the {@code Type}s representing the interfaces
1109 * directly implemented by the class or interface represented by
1110 * this object.
1111 *
1112 * <p>If a superinterface is a parameterized type, the
1113 * {@code Type} object returned for it must accurately reflect
1114 * the actual type arguments used in the source code. The
1115 * parameterized type representing each superinterface is created
1116 * if it had not been created before. See the declaration of
1117 * {@link java.lang.reflect.ParameterizedType ParameterizedType}
1118 * for the semantics of the creation process for parameterized
1119 * types.
1120 *
1121 * <p>If this object represents a class, the return value is an array
1122 * containing objects representing all interfaces directly implemented by
1123 * the class. The order of the interface objects in the array corresponds
1124 * to the order of the interface names in the {@code implements} clause of
1125 * the declaration of the class represented by this object.
1126 *
1127 * <p>If this object represents an interface, the array contains objects
1128 * representing all interfaces directly extended by the interface. The
1129 * order of the interface objects in the array corresponds to the order of
1130 * the interface names in the {@code extends} clause of the declaration of
1131 * the interface represented by this object.
1132 *
1133 * <p>If this object represents a class or interface that implements no
1134 * interfaces, the method returns an array of length 0.
1135 *
1136 * <p>If this object represents a primitive type or void, the method
1137 * returns an array of length 0.
1138 *
1139 * <p>If this {@code Class} object represents an array type, the
1140 * interfaces {@code Cloneable} and {@code java.io.Serializable} are
1141 * returned in that order.
1142 *
1143 * @throws java.lang.reflect.GenericSignatureFormatError
1144 * if the generic class signature does not conform to the format
1145 * specified in
1146 * <cite>The Java™ Virtual Machine Specification</cite>
1147 * @throws TypeNotPresentException if any of the generic
1148 * superinterfaces refers to a non-existent type declaration
1149 * @throws java.lang.reflect.MalformedParameterizedTypeException
1150 * if any of the generic superinterfaces refer to a parameterized
1151 * type that cannot be instantiated for any reason
1152 * @return an array of interfaces directly implemented by this class
1153 * @since 1.5
1154 */
1155 public Type[] getGenericInterfaces() {
1156 ClassRepository info = getGenericInfo();
1157 return (info == null) ? getInterfaces() : info.getSuperInterfaces();
1158 }
1159
1160
1161 /**
1162 * Returns the {@code Class} representing the component type of an
1163 * array. If this class does not represent an array class this method
1164 * returns null.
1165 *
1166 * @return the {@code Class} representing the component type of this
1167 * class if this class is an array
1168 * @see java.lang.reflect.Array
1169 * @since 1.1
1170 */
1171 public Class<?> getComponentType() {
1172 // Only return for array types. Storage may be reused for Class for instance types.
1173 if (isArray()) {
1174 return componentType;
1175 } else {
1176 return null;
1177 }
1178 }
1179
1180 private final Class<?> componentType;
1181
1182
1183 /**
1184 * Returns the Java language modifiers for this class or interface, encoded
1185 * in an integer. The modifiers consist of the Java Virtual Machine's
1186 * constants for {@code public}, {@code protected},
1187 * {@code private}, {@code final}, {@code static},
1188 * {@code abstract} and {@code interface}; they should be decoded
1189 * using the methods of class {@code Modifier}.
1190 *
1191 * <p> If the underlying class is an array class, then its
1192 * {@code public}, {@code private} and {@code protected}
1193 * modifiers are the same as those of its component type. If this
1194 * {@code Class} represents a primitive type or void, its
1195 * {@code public} modifier is always {@code true}, and its
1196 * {@code protected} and {@code private} modifiers are always
1197 * {@code false}. If this object represents an array class, a
1198 * primitive type or void, then its {@code final} modifier is always
1199 * {@code true} and its interface modifier is always
1200 * {@code false}. The values of its other modifiers are not determined
1201 * by this specification.
1202 *
1203 * <p> The modifier encodings are defined in <em>The Java Virtual Machine
1204 * Specification</em>, table 4.1.
1205 *
1206 * @return the {@code int} representing the modifiers for this class
1207 * @see java.lang.reflect.Modifier
1208 * @since 1.1
1209 */
1210 @HotSpotIntrinsicCandidate
1211 public native int getModifiers();
1212
1213
1214 /**
1215 * Gets the signers of this class.
1216 *
1217 * @return the signers of this class, or null if there are no signers. In
1218 * particular, this method returns null if this object represents
1219 * a primitive type or void.
1220 * @since 1.1
1221 */
1222 public native Object[] getSigners();
1223
1224
1225 /**
1226 * Set the signers of this class.
1227 */
1228 native void setSigners(Object[] signers);
1229
1230
1231 /**
1232 * If this {@code Class} object represents a local or anonymous
1233 * class within a method, returns a {@link
1234 * java.lang.reflect.Method Method} object representing the
1235 * immediately enclosing method of the underlying class. Returns
1236 * {@code null} otherwise.
1237 *
1238 * In particular, this method returns {@code null} if the underlying
1239 * class is a local or anonymous class immediately enclosed by a type
1240 * declaration, instance initializer or static initializer.
1241 *
1242 * @return the immediately enclosing method of the underlying class, if
1243 * that class is a local or anonymous class; otherwise {@code null}.
1244 *
1245 * @throws SecurityException
1246 * If a security manager, <i>s</i>, is present and any of the
1247 * following conditions is met:
1248 *
1249 * <ul>
1250 *
1251 * <li> the caller's class loader is not the same as the
1252 * class loader of the enclosing class and invocation of
1253 * {@link SecurityManager#checkPermission
1254 * s.checkPermission} method with
1255 * {@code RuntimePermission("accessDeclaredMembers")}
1256 * denies access to the methods within the enclosing class
1257 *
1258 * <li> the caller's class loader is not the same as or an
1259 * ancestor of the class loader for the enclosing class and
1260 * invocation of {@link SecurityManager#checkPackageAccess
1261 * s.checkPackageAccess()} denies access to the package
1262 * of the enclosing class
1263 *
1264 * </ul>
1265 * @since 1.5
1266 */
1267 @CallerSensitive
1268 public Method getEnclosingMethod() throws SecurityException {
1269 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1270
1271 if (enclosingInfo == null)
1272 return null;
1273 else {
1274 if (!enclosingInfo.isMethod())
1275 return null;
1276
1277 MethodRepository typeInfo = MethodRepository.make(enclosingInfo.getDescriptor(),
1278 getFactory());
1279 Class<?> returnType = toClass(typeInfo.getReturnType());
1280 Type [] parameterTypes = typeInfo.getParameterTypes();
1281 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length];
1282
1283 // Convert Types to Classes; returned types *should*
1284 // be class objects since the methodDescriptor's used
1285 // don't have generics information
1286 for(int i = 0; i < parameterClasses.length; i++)
1287 parameterClasses[i] = toClass(parameterTypes[i]);
1288
1289 // Perform access check
1290 final Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass();
1291 SecurityManager sm = System.getSecurityManager();
1292 if (sm != null) {
1293 enclosingCandidate.checkMemberAccess(sm, Member.DECLARED,
1294 Reflection.getCallerClass(), true);
1295 }
1296 Method[] candidates = enclosingCandidate.privateGetDeclaredMethods(false);
1297
1298 /*
1299 * Loop over all declared methods; match method name,
1300 * number of and type of parameters, *and* return
1301 * type. Matching return type is also necessary
1302 * because of covariant returns, etc.
1303 */
1304 ReflectionFactory fact = getReflectionFactory();
1305 for (Method m : candidates) {
1306 if (m.getName().equals(enclosingInfo.getName()) &&
1307 arrayContentsEq(parameterClasses,
1308 fact.getExecutableSharedParameterTypes(m))) {
1309 // finally, check return type
1310 if (m.getReturnType().equals(returnType)) {
1311 return fact.copyMethod(m);
1312 }
1313 }
1314 }
1315
1316 throw new InternalError("Enclosing method not found");
1317 }
1318 }
1319
1320 private native Object[] getEnclosingMethod0();
1321
1322 private EnclosingMethodInfo getEnclosingMethodInfo() {
1323 Object[] enclosingInfo = getEnclosingMethod0();
1324 if (enclosingInfo == null)
1325 return null;
1326 else {
1327 return new EnclosingMethodInfo(enclosingInfo);
1328 }
1329 }
1330
1331 private static final class EnclosingMethodInfo {
1332 private final Class<?> enclosingClass;
1333 private final String name;
1334 private final String descriptor;
1335
1336 static void validate(Object[] enclosingInfo) {
1337 if (enclosingInfo.length != 3)
1338 throw new InternalError("Malformed enclosing method information");
1339 try {
1340 // The array is expected to have three elements:
1341
1342 // the immediately enclosing class
1343 Class<?> enclosingClass = (Class<?>)enclosingInfo[0];
1344 assert(enclosingClass != null);
1345
1346 // the immediately enclosing method or constructor's
1347 // name (can be null).
1348 String name = (String)enclosingInfo[1];
1349
1350 // the immediately enclosing method or constructor's
1351 // descriptor (null iff name is).
1352 String descriptor = (String)enclosingInfo[2];
1353 assert((name != null && descriptor != null) || name == descriptor);
1354 } catch (ClassCastException cce) {
1355 throw new InternalError("Invalid type in enclosing method information", cce);
1356 }
1357 }
1358
1359 EnclosingMethodInfo(Object[] enclosingInfo) {
1360 validate(enclosingInfo);
1361 this.enclosingClass = (Class<?>)enclosingInfo[0];
1362 this.name = (String)enclosingInfo[1];
1363 this.descriptor = (String)enclosingInfo[2];
1364 }
1365
1366 boolean isPartial() {
1367 return enclosingClass == null || name == null || descriptor == null;
1368 }
1369
1370 boolean isConstructor() { return !isPartial() && "<init>".equals(name); }
1371
1372 boolean isMethod() { return !isPartial() && !isConstructor() && !"<clinit>".equals(name); }
1373
1374 Class<?> getEnclosingClass() { return enclosingClass; }
1375
1376 String getName() { return name; }
1377
1378 String getDescriptor() { return descriptor; }
1379
1380 }
1381
1382 private static Class<?> toClass(Type o) {
1383 if (o instanceof GenericArrayType)
1384 return Array.newInstance(toClass(((GenericArrayType)o).getGenericComponentType()),
1385 0)
1386 .getClass();
1387 return (Class<?>)o;
1388 }
1389
1390 /**
1391 * If this {@code Class} object represents a local or anonymous
1392 * class within a constructor, returns a {@link
1393 * java.lang.reflect.Constructor Constructor} object representing
1394 * the immediately enclosing constructor of the underlying
1395 * class. Returns {@code null} otherwise. In particular, this
1396 * method returns {@code null} if the underlying class is a local
1397 * or anonymous class immediately enclosed by a type declaration,
1398 * instance initializer or static initializer.
1399 *
1400 * @return the immediately enclosing constructor of the underlying class, if
1401 * that class is a local or anonymous class; otherwise {@code null}.
1402 * @throws SecurityException
1403 * If a security manager, <i>s</i>, is present and any of the
1404 * following conditions is met:
1405 *
1406 * <ul>
1407 *
1408 * <li> the caller's class loader is not the same as the
1409 * class loader of the enclosing class and invocation of
1410 * {@link SecurityManager#checkPermission
1411 * s.checkPermission} method with
1412 * {@code RuntimePermission("accessDeclaredMembers")}
1413 * denies access to the constructors within the enclosing class
1414 *
1415 * <li> the caller's class loader is not the same as or an
1416 * ancestor of the class loader for the enclosing class and
1417 * invocation of {@link SecurityManager#checkPackageAccess
1418 * s.checkPackageAccess()} denies access to the package
1419 * of the enclosing class
1420 *
1421 * </ul>
1422 * @since 1.5
1423 */
1424 @CallerSensitive
1425 public Constructor<?> getEnclosingConstructor() throws SecurityException {
1426 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1427
1428 if (enclosingInfo == null)
1429 return null;
1430 else {
1431 if (!enclosingInfo.isConstructor())
1432 return null;
1433
1434 ConstructorRepository typeInfo = ConstructorRepository.make(enclosingInfo.getDescriptor(),
1435 getFactory());
1436 Type [] parameterTypes = typeInfo.getParameterTypes();
1437 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length];
1438
1439 // Convert Types to Classes; returned types *should*
1440 // be class objects since the methodDescriptor's used
1441 // don't have generics information
1442 for(int i = 0; i < parameterClasses.length; i++)
1443 parameterClasses[i] = toClass(parameterTypes[i]);
1444
1445 // Perform access check
1446 final Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass();
1447 SecurityManager sm = System.getSecurityManager();
1448 if (sm != null) {
1449 enclosingCandidate.checkMemberAccess(sm, Member.DECLARED,
1450 Reflection.getCallerClass(), true);
1451 }
1452
1453 Constructor<?>[] candidates = enclosingCandidate
1454 .privateGetDeclaredConstructors(false);
1455 /*
1456 * Loop over all declared constructors; match number
1457 * of and type of parameters.
1458 */
1459 ReflectionFactory fact = getReflectionFactory();
1460 for (Constructor<?> c : candidates) {
1461 if (arrayContentsEq(parameterClasses,
1462 fact.getExecutableSharedParameterTypes(c))) {
1463 return fact.copyConstructor(c);
1464 }
1465 }
1466
1467 throw new InternalError("Enclosing constructor not found");
1468 }
1469 }
1470
1471
1472 /**
1473 * If the class or interface represented by this {@code Class} object
1474 * is a member of another class, returns the {@code Class} object
1475 * representing the class in which it was declared. This method returns
1476 * null if this class or interface is not a member of any other class. If
1477 * this {@code Class} object represents an array class, a primitive
1478 * type, or void,then this method returns null.
1479 *
1480 * @return the declaring class for this class
1481 * @throws SecurityException
1482 * If a security manager, <i>s</i>, is present and the caller's
1483 * class loader is not the same as or an ancestor of the class
1484 * loader for the declaring class and invocation of {@link
1485 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
1486 * denies access to the package of the declaring class
1487 * @since 1.1
1488 */
1489 @CallerSensitive
1490 public Class<?> getDeclaringClass() throws SecurityException {
1491 final Class<?> candidate = getDeclaringClass0();
1492
1493 if (candidate != null) {
1494 SecurityManager sm = System.getSecurityManager();
1495 if (sm != null) {
1496 candidate.checkPackageAccess(sm,
1497 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
1498 }
1499 }
1500 return candidate;
1501 }
1502
1503 private native Class<?> getDeclaringClass0();
1504
1505
1506 /**
1507 * Returns the immediately enclosing class of the underlying
1508 * class. If the underlying class is a top level class this
1509 * method returns {@code null}.
1510 * @return the immediately enclosing class of the underlying class
1511 * @throws SecurityException
1512 * If a security manager, <i>s</i>, is present and the caller's
1513 * class loader is not the same as or an ancestor of the class
1514 * loader for the enclosing class and invocation of {@link
1515 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
1516 * denies access to the package of the enclosing class
1517 * @since 1.5
1518 */
1519 @CallerSensitive
1520 public Class<?> getEnclosingClass() throws SecurityException {
1521 // There are five kinds of classes (or interfaces):
1522 // a) Top level classes
1523 // b) Nested classes (static member classes)
1524 // c) Inner classes (non-static member classes)
1525 // d) Local classes (named classes declared within a method)
1526 // e) Anonymous classes
1527
1528
1529 // JVM Spec 4.7.7: A class must have an EnclosingMethod
1530 // attribute if and only if it is a local class or an
1531 // anonymous class.
1532 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1533 Class<?> enclosingCandidate;
1534
1535 if (enclosingInfo == null) {
1536 // This is a top level or a nested class or an inner class (a, b, or c)
1537 enclosingCandidate = getDeclaringClass0();
1538 } else {
1539 Class<?> enclosingClass = enclosingInfo.getEnclosingClass();
1540 // This is a local class or an anonymous class (d or e)
1541 if (enclosingClass == this || enclosingClass == null)
1542 throw new InternalError("Malformed enclosing method information");
1543 else
1544 enclosingCandidate = enclosingClass;
1545 }
1546
1547 if (enclosingCandidate != null) {
1548 SecurityManager sm = System.getSecurityManager();
1549 if (sm != null) {
1550 enclosingCandidate.checkPackageAccess(sm,
1551 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
1552 }
1553 }
1554 return enclosingCandidate;
1555 }
1556
1557 /**
1558 * Returns the simple name of the underlying class as given in the
1559 * source code. Returns an empty string if the underlying class is
1560 * anonymous.
1561 *
1562 * <p>The simple name of an array is the simple name of the
1563 * component type with "[]" appended. In particular the simple
1564 * name of an array whose component type is anonymous is "[]".
1565 *
1566 * @return the simple name of the underlying class
1567 * @since 1.5
1568 */
1569 public String getSimpleName() {
1570 ReflectionData<T> rd = reflectionData();
1571 String simpleName = rd.simpleName;
1572 if (simpleName == null) {
1573 rd.simpleName = simpleName = getSimpleName0();
1574 }
1575 return simpleName;
1576 }
1577
1578 private String getSimpleName0() {
1579 if (isArray()) {
1580 return getComponentType().getSimpleName() + "[]";
1581 }
1582 String simpleName = getSimpleBinaryName();
1583 if (simpleName == null) { // top level class
1584 simpleName = getName();
1585 simpleName = simpleName.substring(simpleName.lastIndexOf('.') + 1); // strip the package name
1586 }
1587 return simpleName;
1588 }
1589
1590 /**
1591 * Return an informative string for the name of this type.
1592 *
1593 * @return an informative string for the name of this type
1594 * @since 1.8
1595 */
1596 public String getTypeName() {
1597 if (isArray()) {
1598 try {
1599 Class<?> cl = this;
1600 int dimensions = 0;
1601 do {
1602 dimensions++;
1603 cl = cl.getComponentType();
1604 } while (cl.isArray());
1605 return cl.getName() + "[]".repeat(dimensions);
1606 } catch (Throwable e) { /*FALLTHRU*/ }
1607 }
1608 return getName();
1609 }
1610
1611 /**
1612 * Returns the canonical name of the underlying class as
1613 * defined by the Java Language Specification. Returns null if
1614 * the underlying class does not have a canonical name (i.e., if
1615 * it is a local or anonymous class or an array whose component
1616 * type does not have a canonical name).
1617 * @return the canonical name of the underlying class if it exists, and
1618 * {@code null} otherwise.
1619 * @since 1.5
1620 */
1621 public String getCanonicalName() {
1622 ReflectionData<T> rd = reflectionData();
1623 String canonicalName = rd.canonicalName;
1624 if (canonicalName == null) {
1625 rd.canonicalName = canonicalName = getCanonicalName0();
1626 }
1627 return canonicalName == ReflectionData.NULL_SENTINEL? null : canonicalName;
1628 }
1629
1630 private String getCanonicalName0() {
1631 if (isArray()) {
1632 String canonicalName = getComponentType().getCanonicalName();
1633 if (canonicalName != null)
1634 return canonicalName + "[]";
1635 else
1636 return ReflectionData.NULL_SENTINEL;
1637 }
1638 if (isLocalOrAnonymousClass())
1639 return ReflectionData.NULL_SENTINEL;
1640 Class<?> enclosingClass = getEnclosingClass();
1641 if (enclosingClass == null) { // top level class
1642 return getName();
1643 } else {
1644 String enclosingName = enclosingClass.getCanonicalName();
1645 if (enclosingName == null)
1646 return ReflectionData.NULL_SENTINEL;
1647 return enclosingName + "." + getSimpleName();
1648 }
1649 }
1650
1651 /**
1652 * Returns {@code true} if and only if the underlying class
1653 * is an anonymous class.
1654 *
1655 * @return {@code true} if and only if this class is an anonymous class.
1656 * @since 1.5
1657 */
1658 public boolean isAnonymousClass() {
1659 return !isArray() && isLocalOrAnonymousClass() &&
1660 getSimpleBinaryName0() == null;
1661 }
1662
1663 /**
1664 * Returns {@code true} if and only if the underlying class
1665 * is a local class.
1666 *
1667 * @return {@code true} if and only if this class is a local class.
1668 * @since 1.5
1669 */
1670 public boolean isLocalClass() {
1671 return isLocalOrAnonymousClass() &&
1672 (isArray() || getSimpleBinaryName0() != null);
1673 }
1674
1675 /**
1676 * Returns {@code true} if and only if the underlying class
1677 * is a member class.
1678 *
1679 * @return {@code true} if and only if this class is a member class.
1680 * @since 1.5
1681 */
1682 public boolean isMemberClass() {
1683 return !isLocalOrAnonymousClass() && getDeclaringClass0() != null;
1684 }
1685
1686 /**
1687 * Returns the "simple binary name" of the underlying class, i.e.,
1688 * the binary name without the leading enclosing class name.
1689 * Returns {@code null} if the underlying class is a top level
1690 * class.
1691 */
1692 private String getSimpleBinaryName() {
1693 if (isTopLevelClass())
1694 return null;
1695 String name = getSimpleBinaryName0();
1696 if (name == null) // anonymous class
1697 return "";
1698 return name;
1699 }
1700
1701 private native String getSimpleBinaryName0();
1702
1703 /**
1704 * Returns {@code true} if this is a top level class. Returns {@code false}
1705 * otherwise.
1706 */
1707 private boolean isTopLevelClass() {
1708 return !isLocalOrAnonymousClass() && getDeclaringClass0() == null;
1709 }
1710
1711 /**
1712 * Returns {@code true} if this is a local class or an anonymous
1713 * class. Returns {@code false} otherwise.
1714 */
1715 private boolean isLocalOrAnonymousClass() {
1716 // JVM Spec 4.7.7: A class must have an EnclosingMethod
1717 // attribute if and only if it is a local class or an
1718 // anonymous class.
1719 return hasEnclosingMethodInfo();
1720 }
1721
1722 private boolean hasEnclosingMethodInfo() {
1723 Object[] enclosingInfo = getEnclosingMethod0();
1724 if (enclosingInfo != null) {
1725 EnclosingMethodInfo.validate(enclosingInfo);
1726 return true;
1727 }
1728 return false;
1729 }
1730
1731 /**
1732 * Returns an array containing {@code Class} objects representing all
1733 * the public classes and interfaces that are members of the class
1734 * represented by this {@code Class} object. This includes public
1735 * class and interface members inherited from superclasses and public class
1736 * and interface members declared by the class. This method returns an
1737 * array of length 0 if this {@code Class} object has no public member
1738 * classes or interfaces. This method also returns an array of length 0 if
1739 * this {@code Class} object represents a primitive type, an array
1740 * class, or void.
1741 *
1742 * @return the array of {@code Class} objects representing the public
1743 * members of this class
1744 * @throws SecurityException
1745 * If a security manager, <i>s</i>, is present and
1746 * the caller's class loader is not the same as or an
1747 * ancestor of the class loader for the current class and
1748 * invocation of {@link SecurityManager#checkPackageAccess
1749 * s.checkPackageAccess()} denies access to the package
1750 * of this class.
1751 *
1752 * @since 1.1
1753 */
1754 @CallerSensitive
1755 public Class<?>[] getClasses() {
1756 SecurityManager sm = System.getSecurityManager();
1757 if (sm != null) {
1758 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), false);
1759 }
1760
1761 // Privileged so this implementation can look at DECLARED classes,
1762 // something the caller might not have privilege to do. The code here
1763 // is allowed to look at DECLARED classes because (1) it does not hand
1764 // out anything other than public members and (2) public member access
1765 // has already been ok'd by the SecurityManager.
1766
1767 return java.security.AccessController.doPrivileged(
1768 new java.security.PrivilegedAction<>() {
1769 public Class<?>[] run() {
1770 List<Class<?>> list = new ArrayList<>();
1771 Class<?> currentClass = Class.this;
1772 while (currentClass != null) {
1773 for (Class<?> m : currentClass.getDeclaredClasses()) {
1774 if (Modifier.isPublic(m.getModifiers())) {
1775 list.add(m);
1776 }
1777 }
1778 currentClass = currentClass.getSuperclass();
1779 }
1780 return list.toArray(new Class<?>[0]);
1781 }
1782 });
1783 }
1784
1785
1786 /**
1787 * Returns an array containing {@code Field} objects reflecting all
1788 * the accessible public fields of the class or interface represented by
1789 * this {@code Class} object.
1790 *
1791 * <p> If this {@code Class} object represents a class or interface with
1792 * no accessible public fields, then this method returns an array of length
1793 * 0.
1794 *
1795 * <p> If this {@code Class} object represents a class, then this method
1796 * returns the public fields of the class and of all its superclasses and
1797 * superinterfaces.
1798 *
1799 * <p> If this {@code Class} object represents an interface, then this
1800 * method returns the fields of the interface and of all its
1801 * superinterfaces.
1802 *
1803 * <p> If this {@code Class} object represents an array type, a primitive
1804 * type, or void, then this method returns an array of length 0.
1805 *
1806 * <p> The elements in the returned array are not sorted and are not in any
1807 * particular order.
1808 *
1809 * @return the array of {@code Field} objects representing the
1810 * public fields
1811 * @throws SecurityException
1812 * If a security manager, <i>s</i>, is present and
1813 * the caller's class loader is not the same as or an
1814 * ancestor of the class loader for the current class and
1815 * invocation of {@link SecurityManager#checkPackageAccess
1816 * s.checkPackageAccess()} denies access to the package
1817 * of this class.
1818 *
1819 * @since 1.1
1820 * @jls 8.2 Class Members
1821 * @jls 8.3 Field Declarations
1822 */
1823 @CallerSensitive
1824 public Field[] getFields() throws SecurityException {
1825 SecurityManager sm = System.getSecurityManager();
1826 if (sm != null) {
1827 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
1828 }
1829 return copyFields(privateGetPublicFields());
1830 }
1831
1832
1833 /**
1834 * Returns an array containing {@code Method} objects reflecting all the
1835 * public methods of the class or interface represented by this {@code
1836 * Class} object, including those declared by the class or interface and
1837 * those inherited from superclasses and superinterfaces.
1838 *
1839 * <p> If this {@code Class} object represents an array type, then the
1840 * returned array has a {@code Method} object for each of the public
1841 * methods inherited by the array type from {@code Object}. It does not
1842 * contain a {@code Method} object for {@code clone()}.
1843 *
1844 * <p> If this {@code Class} object represents an interface then the
1845 * returned array does not contain any implicitly declared methods from
1846 * {@code Object}. Therefore, if no methods are explicitly declared in
1847 * this interface or any of its superinterfaces then the returned array
1848 * has length 0. (Note that a {@code Class} object which represents a class
1849 * always has public methods, inherited from {@code Object}.)
1850 *
1851 * <p> The returned array never contains methods with names "{@code <init>}"
1852 * or "{@code <clinit>}".
1853 *
1854 * <p> The elements in the returned array are not sorted and are not in any
1855 * particular order.
1856 *
1857 * <p> Generally, the result is computed as with the following 4 step algorithm.
1858 * Let C be the class or interface represented by this {@code Class} object:
1859 * <ol>
1860 * <li> A union of methods is composed of:
1861 * <ol type="a">
1862 * <li> C's declared public instance and static methods as returned by
1863 * {@link #getDeclaredMethods()} and filtered to include only public
1864 * methods.</li>
1865 * <li> If C is a class other than {@code Object}, then include the result
1866 * of invoking this algorithm recursively on the superclass of C.</li>
1867 * <li> Include the results of invoking this algorithm recursively on all
1868 * direct superinterfaces of C, but include only instance methods.</li>
1869 * </ol></li>
1870 * <li> Union from step 1 is partitioned into subsets of methods with same
1871 * signature (name, parameter types) and return type.</li>
1872 * <li> Within each such subset only the most specific methods are selected.
1873 * Let method M be a method from a set of methods with same signature
1874 * and return type. M is most specific if there is no such method
1875 * N != M from the same set, such that N is more specific than M.
1876 * N is more specific than M if:
1877 * <ol type="a">
1878 * <li> N is declared by a class and M is declared by an interface; or</li>
1879 * <li> N and M are both declared by classes or both by interfaces and
1880 * N's declaring type is the same as or a subtype of M's declaring type
1881 * (clearly, if M's and N's declaring types are the same type, then
1882 * M and N are the same method).</li>
1883 * </ol></li>
1884 * <li> The result of this algorithm is the union of all selected methods from
1885 * step 3.</li>
1886 * </ol>
1887 *
1888 * @apiNote There may be more than one method with a particular name
1889 * and parameter types in a class because while the Java language forbids a
1890 * class to declare multiple methods with the same signature but different
1891 * return types, the Java virtual machine does not. This
1892 * increased flexibility in the virtual machine can be used to
1893 * implement various language features. For example, covariant
1894 * returns can be implemented with {@linkplain
1895 * java.lang.reflect.Method#isBridge bridge methods}; the bridge
1896 * method and the overriding method would have the same
1897 * signature but different return types.
1898 *
1899 * @return the array of {@code Method} objects representing the
1900 * public methods of this class
1901 * @throws SecurityException
1902 * If a security manager, <i>s</i>, is present and
1903 * the caller's class loader is not the same as or an
1904 * ancestor of the class loader for the current class and
1905 * invocation of {@link SecurityManager#checkPackageAccess
1906 * s.checkPackageAccess()} denies access to the package
1907 * of this class.
1908 *
1909 * @jls 8.2 Class Members
1910 * @jls 8.4 Method Declarations
1911 * @since 1.1
1912 */
1913 @CallerSensitive
1914 public Method[] getMethods() throws SecurityException {
1915 SecurityManager sm = System.getSecurityManager();
1916 if (sm != null) {
1917 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
1918 }
1919 return copyMethods(privateGetPublicMethods());
1920 }
1921
1922
1923 /**
1924 * Returns an array containing {@code Constructor} objects reflecting
1925 * all the public constructors of the class represented by this
1926 * {@code Class} object. An array of length 0 is returned if the
1927 * class has no public constructors, or if the class is an array class, or
1928 * if the class reflects a primitive type or void.
1929 *
1930 * Note that while this method returns an array of {@code
1931 * Constructor<T>} objects (that is an array of constructors from
1932 * this class), the return type of this method is {@code
1933 * Constructor<?>[]} and <em>not</em> {@code Constructor<T>[]} as
1934 * might be expected. This less informative return type is
1935 * necessary since after being returned from this method, the
1936 * array could be modified to hold {@code Constructor} objects for
1937 * different classes, which would violate the type guarantees of
1938 * {@code Constructor<T>[]}.
1939 *
1940 * @return the array of {@code Constructor} objects representing the
1941 * public constructors of this class
1942 * @throws SecurityException
1943 * If a security manager, <i>s</i>, is present and
1944 * the caller's class loader is not the same as or an
1945 * ancestor of the class loader for the current class and
1946 * invocation of {@link SecurityManager#checkPackageAccess
1947 * s.checkPackageAccess()} denies access to the package
1948 * of this class.
1949 *
1950 * @since 1.1
1951 */
1952 @CallerSensitive
1953 public Constructor<?>[] getConstructors() throws SecurityException {
1954 SecurityManager sm = System.getSecurityManager();
1955 if (sm != null) {
1956 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
1957 }
1958 return copyConstructors(privateGetDeclaredConstructors(true));
1959 }
1960
1961
1962 /**
1963 * Returns a {@code Field} object that reflects the specified public member
1964 * field of the class or interface represented by this {@code Class}
1965 * object. The {@code name} parameter is a {@code String} specifying the
1966 * simple name of the desired field.
1967 *
1968 * <p> The field to be reflected is determined by the algorithm that
1969 * follows. Let C be the class or interface represented by this object:
1970 *
1971 * <OL>
1972 * <LI> If C declares a public field with the name specified, that is the
1973 * field to be reflected.</LI>
1974 * <LI> If no field was found in step 1 above, this algorithm is applied
1975 * recursively to each direct superinterface of C. The direct
1976 * superinterfaces are searched in the order they were declared.</LI>
1977 * <LI> If no field was found in steps 1 and 2 above, and C has a
1978 * superclass S, then this algorithm is invoked recursively upon S.
1979 * If C has no superclass, then a {@code NoSuchFieldException}
1980 * is thrown.</LI>
1981 * </OL>
1982 *
1983 * <p> If this {@code Class} object represents an array type, then this
1984 * method does not find the {@code length} field of the array type.
1985 *
1986 * @param name the field name
1987 * @return the {@code Field} object of this class specified by
1988 * {@code name}
1989 * @throws NoSuchFieldException if a field with the specified name is
1990 * not found.
1991 * @throws NullPointerException if {@code name} is {@code null}
1992 * @throws SecurityException
1993 * If a security manager, <i>s</i>, is present and
1994 * the caller's class loader is not the same as or an
1995 * ancestor of the class loader for the current class and
1996 * invocation of {@link SecurityManager#checkPackageAccess
1997 * s.checkPackageAccess()} denies access to the package
1998 * of this class.
1999 *
2000 * @since 1.1
2001 * @jls 8.2 Class Members
2002 * @jls 8.3 Field Declarations
2003 */
2004 @CallerSensitive
2005 public Field getField(String name)
2006 throws NoSuchFieldException, SecurityException {
2007 Objects.requireNonNull(name);
2008 SecurityManager sm = System.getSecurityManager();
2009 if (sm != null) {
2010 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2011 }
2012 Field field = getField0(name);
2013 if (field == null) {
2014 throw new NoSuchFieldException(name);
2015 }
2016 return getReflectionFactory().copyField(field);
2017 }
2018
2019
2020 /**
2021 * Returns a {@code Method} object that reflects the specified public
2022 * member method of the class or interface represented by this
2023 * {@code Class} object. The {@code name} parameter is a
2024 * {@code String} specifying the simple name of the desired method. The
2025 * {@code parameterTypes} parameter is an array of {@code Class}
2026 * objects that identify the method's formal parameter types, in declared
2027 * order. If {@code parameterTypes} is {@code null}, it is
2028 * treated as if it were an empty array.
2029 *
2030 * <p> If this {@code Class} object represents an array type, then this
2031 * method finds any public method inherited by the array type from
2032 * {@code Object} except method {@code clone()}.
2033 *
2034 * <p> If this {@code Class} object represents an interface then this
2035 * method does not find any implicitly declared method from
2036 * {@code Object}. Therefore, if no methods are explicitly declared in
2037 * this interface or any of its superinterfaces, then this method does not
2038 * find any method.
2039 *
2040 * <p> This method does not find any method with name "{@code <init>}" or
2041 * "{@code <clinit>}".
2042 *
2043 * <p> Generally, the method to be reflected is determined by the 4 step
2044 * algorithm that follows.
2045 * Let C be the class or interface represented by this {@code Class} object:
2046 * <ol>
2047 * <li> A union of methods is composed of:
2048 * <ol type="a">
2049 * <li> C's declared public instance and static methods as returned by
2050 * {@link #getDeclaredMethods()} and filtered to include only public
2051 * methods that match given {@code name} and {@code parameterTypes}</li>
2052 * <li> If C is a class other than {@code Object}, then include the result
2053 * of invoking this algorithm recursively on the superclass of C.</li>
2054 * <li> Include the results of invoking this algorithm recursively on all
2055 * direct superinterfaces of C, but include only instance methods.</li>
2056 * </ol></li>
2057 * <li> This union is partitioned into subsets of methods with same
2058 * return type (the selection of methods from step 1 also guarantees that
2059 * they have the same method name and parameter types).</li>
2060 * <li> Within each such subset only the most specific methods are selected.
2061 * Let method M be a method from a set of methods with same VM
2062 * signature (return type, name, parameter types).
2063 * M is most specific if there is no such method N != M from the same
2064 * set, such that N is more specific than M. N is more specific than M
2065 * if:
2066 * <ol type="a">
2067 * <li> N is declared by a class and M is declared by an interface; or</li>
2068 * <li> N and M are both declared by classes or both by interfaces and
2069 * N's declaring type is the same as or a subtype of M's declaring type
2070 * (clearly, if M's and N's declaring types are the same type, then
2071 * M and N are the same method).</li>
2072 * </ol></li>
2073 * <li> The result of this algorithm is chosen arbitrarily from the methods
2074 * with most specific return type among all selected methods from step 3.
2075 * Let R be a return type of a method M from the set of all selected methods
2076 * from step 3. M is a method with most specific return type if there is
2077 * no such method N != M from the same set, having return type S != R,
2078 * such that S is a subtype of R as determined by
2079 * R.class.{@link #isAssignableFrom}(S.class).
2080 * </ol>
2081 *
2082 * @apiNote There may be more than one method with matching name and
2083 * parameter types in a class because while the Java language forbids a
2084 * class to declare multiple methods with the same signature but different
2085 * return types, the Java virtual machine does not. This
2086 * increased flexibility in the virtual machine can be used to
2087 * implement various language features. For example, covariant
2088 * returns can be implemented with {@linkplain
2089 * java.lang.reflect.Method#isBridge bridge methods}; the bridge
2090 * method and the overriding method would have the same
2091 * signature but different return types. This method would return the
2092 * overriding method as it would have a more specific return type.
2093 *
2094 * @param name the name of the method
2095 * @param parameterTypes the list of parameters
2096 * @return the {@code Method} object that matches the specified
2097 * {@code name} and {@code parameterTypes}
2098 * @throws NoSuchMethodException if a matching method is not found
2099 * or if the name is "<init>"or "<clinit>".
2100 * @throws NullPointerException if {@code name} is {@code null}
2101 * @throws SecurityException
2102 * If a security manager, <i>s</i>, is present and
2103 * the caller's class loader is not the same as or an
2104 * ancestor of the class loader for the current class and
2105 * invocation of {@link SecurityManager#checkPackageAccess
2106 * s.checkPackageAccess()} denies access to the package
2107 * of this class.
2108 *
2109 * @jls 8.2 Class Members
2110 * @jls 8.4 Method Declarations
2111 * @since 1.1
2112 */
2113 @CallerSensitive
2114 public Method getMethod(String name, Class<?>... parameterTypes)
2115 throws NoSuchMethodException, SecurityException {
2116 Objects.requireNonNull(name);
2117 SecurityManager sm = System.getSecurityManager();
2118 if (sm != null) {
2119 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2120 }
2121 Method method = getMethod0(name, parameterTypes);
2122 if (method == null) {
2123 throw new NoSuchMethodException(methodToString(name, parameterTypes));
2124 }
2125 return getReflectionFactory().copyMethod(method);
2126 }
2127
2128 /**
2129 * Returns a {@code Constructor} object that reflects the specified
2130 * public constructor of the class represented by this {@code Class}
2131 * object. The {@code parameterTypes} parameter is an array of
2132 * {@code Class} objects that identify the constructor's formal
2133 * parameter types, in declared order.
2134 *
2135 * If this {@code Class} object represents an inner class
2136 * declared in a non-static context, the formal parameter types
2137 * include the explicit enclosing instance as the first parameter.
2138 *
2139 * <p> The constructor to reflect is the public constructor of the class
2140 * represented by this {@code Class} object whose formal parameter
2141 * types match those specified by {@code parameterTypes}.
2142 *
2143 * @param parameterTypes the parameter array
2144 * @return the {@code Constructor} object of the public constructor that
2145 * matches the specified {@code parameterTypes}
2146 * @throws NoSuchMethodException if a matching method is not found.
2147 * @throws SecurityException
2148 * If a security manager, <i>s</i>, is present and
2149 * the caller's class loader is not the same as or an
2150 * ancestor of the class loader for the current class and
2151 * invocation of {@link SecurityManager#checkPackageAccess
2152 * s.checkPackageAccess()} denies access to the package
2153 * of this class.
2154 *
2155 * @since 1.1
2156 */
2157 @CallerSensitive
2158 public Constructor<T> getConstructor(Class<?>... parameterTypes)
2159 throws NoSuchMethodException, SecurityException
2160 {
2161 SecurityManager sm = System.getSecurityManager();
2162 if (sm != null) {
2163 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2164 }
2165 return getReflectionFactory().copyConstructor(
2166 getConstructor0(parameterTypes, Member.PUBLIC));
2167 }
2168
2169
2170 /**
2171 * Returns an array of {@code Class} objects reflecting all the
2172 * classes and interfaces declared as members of the class represented by
2173 * this {@code Class} object. This includes public, protected, default
2174 * (package) access, and private classes and interfaces declared by the
2175 * class, but excludes inherited classes and interfaces. This method
2176 * returns an array of length 0 if the class declares no classes or
2177 * interfaces as members, or if this {@code Class} object represents a
2178 * primitive type, an array class, or void.
2179 *
2180 * @return the array of {@code Class} objects representing all the
2181 * declared members of this class
2182 * @throws SecurityException
2183 * If a security manager, <i>s</i>, is present and any of the
2184 * following conditions is met:
2185 *
2186 * <ul>
2187 *
2188 * <li> the caller's class loader is not the same as the
2189 * class loader of this class and invocation of
2190 * {@link SecurityManager#checkPermission
2191 * s.checkPermission} method with
2192 * {@code RuntimePermission("accessDeclaredMembers")}
2193 * denies access to the declared classes within this class
2194 *
2195 * <li> the caller's class loader is not the same as or an
2196 * ancestor of the class loader for the current class and
2197 * invocation of {@link SecurityManager#checkPackageAccess
2198 * s.checkPackageAccess()} denies access to the package
2199 * of this class
2200 *
2201 * </ul>
2202 *
2203 * @since 1.1
2204 */
2205 @CallerSensitive
2206 public Class<?>[] getDeclaredClasses() throws SecurityException {
2207 SecurityManager sm = System.getSecurityManager();
2208 if (sm != null) {
2209 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), false);
2210 }
2211 return getDeclaredClasses0();
2212 }
2213
2214
2215 /**
2216 * Returns an array of {@code Field} objects reflecting all the fields
2217 * declared by the class or interface represented by this
2218 * {@code Class} object. This includes public, protected, default
2219 * (package) access, and private fields, but excludes inherited fields.
2220 *
2221 * <p> If this {@code Class} object represents a class or interface with no
2222 * declared fields, then this method returns an array of length 0.
2223 *
2224 * <p> If this {@code Class} object represents an array type, a primitive
2225 * type, or void, then this method returns an array of length 0.
2226 *
2227 * <p> The elements in the returned array are not sorted and are not in any
2228 * particular order.
2229 *
2230 * @return the array of {@code Field} objects representing all the
2231 * declared fields of this class
2232 * @throws SecurityException
2233 * If a security manager, <i>s</i>, is present and any of the
2234 * following conditions is met:
2235 *
2236 * <ul>
2237 *
2238 * <li> the caller's class loader is not the same as the
2239 * class loader of this class and invocation of
2240 * {@link SecurityManager#checkPermission
2241 * s.checkPermission} method with
2242 * {@code RuntimePermission("accessDeclaredMembers")}
2243 * denies access to the declared fields within this class
2244 *
2245 * <li> the caller's class loader is not the same as or an
2246 * ancestor of the class loader for the current class and
2247 * invocation of {@link SecurityManager#checkPackageAccess
2248 * s.checkPackageAccess()} denies access to the package
2249 * of this class
2250 *
2251 * </ul>
2252 *
2253 * @since 1.1
2254 * @jls 8.2 Class Members
2255 * @jls 8.3 Field Declarations
2256 */
2257 @CallerSensitive
2258 public Field[] getDeclaredFields() throws SecurityException {
2259 SecurityManager sm = System.getSecurityManager();
2260 if (sm != null) {
2261 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2262 }
2263 return copyFields(privateGetDeclaredFields(false));
2264 }
2265
2266 /**
2267 * {@preview Associated with records, a preview feature of the Java language.
2268 *
2269 * This method is associated with <i>records</i>, a preview
2270 * feature of the Java language. Preview features
2271 * may be removed in a future release, or upgraded to permanent
2272 * features of the Java language.}
2273 *
2274 * Returns an array containing {@code RecordComponent} objects reflecting all the
2275 * declared record components of the record represented by this {@code Class} object.
2276 * The components are returned in the same order that they are declared in the
2277 * record header.
2278 *
2279 * @return The array of {@code RecordComponent} objects representing all the
2280 * record components of this record. The array is empty if this class
2281 * is not a record, or if this class is a record with no components.
2282 * @throws SecurityException
2283 * If a security manager, <i>s</i>, is present and any of the
2284 * following conditions is met:
2285 *
2286 * <ul>
2287 *
2288 * <li> the caller's class loader is not the same as the
2289 * class loader of this class and invocation of
2290 * {@link SecurityManager#checkPermission
2291 * s.checkPermission} method with
2292 * {@code RuntimePermission("accessDeclaredMembers")}
2293 * denies access to the declared methods within this class
2294 *
2295 * <li> the caller's class loader is not the same as or an
2296 * ancestor of the class loader for the current class and
2297 * invocation of {@link SecurityManager#checkPackageAccess
2298 * s.checkPackageAccess()} denies access to the package
2299 * of this class
2300 *
2301 * </ul>
2302 *
2303 * @jls 8.10 Record Types
2304 * @since 14
2305 */
2306 @jdk.internal.PreviewFeature(feature=jdk.internal.PreviewFeature.Feature.RECORDS,
2307 essentialAPI=false)
2308 @SuppressWarnings("preview")
2309 @CallerSensitive
2310 public RecordComponent[] getRecordComponents() {
2311 SecurityManager sm = System.getSecurityManager();
2312 if (sm != null) {
2313 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2314 }
2315 if (isPrimitive() || isArray()) {
2316 return new RecordComponent[0];
2317 }
2318 Object[] recordComponents = getRecordComponents0();
2319 if (recordComponents == null || recordComponents.length == 0) {
2320 return new RecordComponent[0];
2321 }
2322 RecordComponent[] result = new RecordComponent[recordComponents.length];
2323 for (int i = 0; i < recordComponents.length; i++) {
2324 result[i] = (RecordComponent)recordComponents[i];
2325 }
2326 return result;
2327 }
2328
2329 /**
2330 * Returns an array containing {@code Method} objects reflecting all the
2331 * declared methods of the class or interface represented by this {@code
2332 * Class} object, including public, protected, default (package)
2333 * access, and private methods, but excluding inherited methods.
2334 *
2335 * <p> If this {@code Class} object represents a type that has multiple
2336 * declared methods with the same name and parameter types, but different
2337 * return types, then the returned array has a {@code Method} object for
2338 * each such method.
2339 *
2340 * <p> If this {@code Class} object represents a type that has a class
2341 * initialization method {@code <clinit>}, then the returned array does
2342 * <em>not</em> have a corresponding {@code Method} object.
2343 *
2344 * <p> If this {@code Class} object represents a class or interface with no
2345 * declared methods, then the returned array has length 0.
2346 *
2347 * <p> If this {@code Class} object represents an array type, a primitive
2348 * type, or void, then the returned array has length 0.
2349 *
2350 * <p> The elements in the returned array are not sorted and are not in any
2351 * particular order.
2352 *
2353 * @return the array of {@code Method} objects representing all the
2354 * declared methods of this class
2355 * @throws SecurityException
2356 * If a security manager, <i>s</i>, is present and any of the
2357 * following conditions is met:
2358 *
2359 * <ul>
2360 *
2361 * <li> the caller's class loader is not the same as the
2362 * class loader of this class and invocation of
2363 * {@link SecurityManager#checkPermission
2364 * s.checkPermission} method with
2365 * {@code RuntimePermission("accessDeclaredMembers")}
2366 * denies access to the declared methods within this class
2367 *
2368 * <li> the caller's class loader is not the same as or an
2369 * ancestor of the class loader for the current class and
2370 * invocation of {@link SecurityManager#checkPackageAccess
2371 * s.checkPackageAccess()} denies access to the package
2372 * of this class
2373 *
2374 * </ul>
2375 *
2376 * @jls 8.2 Class Members
2377 * @jls 8.4 Method Declarations
2378 * @since 1.1
2379 */
2380 @CallerSensitive
2381 public Method[] getDeclaredMethods() throws SecurityException {
2382 SecurityManager sm = System.getSecurityManager();
2383 if (sm != null) {
2384 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2385 }
2386 return copyMethods(privateGetDeclaredMethods(false));
2387 }
2388
2389
2390 /**
2391 * Returns an array of {@code Constructor} objects reflecting all the
2392 * constructors declared by the class represented by this
2393 * {@code Class} object. These are public, protected, default
2394 * (package) access, and private constructors. The elements in the array
2395 * returned are not sorted and are not in any particular order. If the
2396 * class has a default constructor, it is included in the returned array.
2397 * This method returns an array of length 0 if this {@code Class}
2398 * object represents an interface, a primitive type, an array class, or
2399 * void.
2400 *
2401 * <p> See <em>The Java Language Specification</em>, section 8.2.
2402 *
2403 * @return the array of {@code Constructor} objects representing all the
2404 * declared constructors of this class
2405 * @throws SecurityException
2406 * If a security manager, <i>s</i>, is present and any of the
2407 * following conditions is met:
2408 *
2409 * <ul>
2410 *
2411 * <li> the caller's class loader is not the same as the
2412 * class loader of this class and invocation of
2413 * {@link SecurityManager#checkPermission
2414 * s.checkPermission} method with
2415 * {@code RuntimePermission("accessDeclaredMembers")}
2416 * denies access to the declared constructors within this class
2417 *
2418 * <li> the caller's class loader is not the same as or an
2419 * ancestor of the class loader for the current class and
2420 * invocation of {@link SecurityManager#checkPackageAccess
2421 * s.checkPackageAccess()} denies access to the package
2422 * of this class
2423 *
2424 * </ul>
2425 *
2426 * @since 1.1
2427 */
2428 @CallerSensitive
2429 public Constructor<?>[] getDeclaredConstructors() throws SecurityException {
2430 SecurityManager sm = System.getSecurityManager();
2431 if (sm != null) {
2432 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2433 }
2434 return copyConstructors(privateGetDeclaredConstructors(false));
2435 }
2436
2437
2438 /**
2439 * Returns a {@code Field} object that reflects the specified declared
2440 * field of the class or interface represented by this {@code Class}
2441 * object. The {@code name} parameter is a {@code String} that specifies
2442 * the simple name of the desired field.
2443 *
2444 * <p> If this {@code Class} object represents an array type, then this
2445 * method does not find the {@code length} field of the array type.
2446 *
2447 * @param name the name of the field
2448 * @return the {@code Field} object for the specified field in this
2449 * class
2450 * @throws NoSuchFieldException if a field with the specified name is
2451 * not found.
2452 * @throws NullPointerException if {@code name} is {@code null}
2453 * @throws SecurityException
2454 * If a security manager, <i>s</i>, is present and any of the
2455 * following conditions is met:
2456 *
2457 * <ul>
2458 *
2459 * <li> the caller's class loader is not the same as the
2460 * class loader of this class and invocation of
2461 * {@link SecurityManager#checkPermission
2462 * s.checkPermission} method with
2463 * {@code RuntimePermission("accessDeclaredMembers")}
2464 * denies access to the declared field
2465 *
2466 * <li> the caller's class loader is not the same as or an
2467 * ancestor of the class loader for the current class and
2468 * invocation of {@link SecurityManager#checkPackageAccess
2469 * s.checkPackageAccess()} denies access to the package
2470 * of this class
2471 *
2472 * </ul>
2473 *
2474 * @since 1.1
2475 * @jls 8.2 Class Members
2476 * @jls 8.3 Field Declarations
2477 */
2478 @CallerSensitive
2479 public Field getDeclaredField(String name)
2480 throws NoSuchFieldException, SecurityException {
2481 Objects.requireNonNull(name);
2482 SecurityManager sm = System.getSecurityManager();
2483 if (sm != null) {
2484 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2485 }
2486 Field field = searchFields(privateGetDeclaredFields(false), name);
2487 if (field == null) {
2488 throw new NoSuchFieldException(name);
2489 }
2490 return getReflectionFactory().copyField(field);
2491 }
2492
2493
2494 /**
2495 * Returns a {@code Method} object that reflects the specified
2496 * declared method of the class or interface represented by this
2497 * {@code Class} object. The {@code name} parameter is a
2498 * {@code String} that specifies the simple name of the desired
2499 * method, and the {@code parameterTypes} parameter is an array of
2500 * {@code Class} objects that identify the method's formal parameter
2501 * types, in declared order. If more than one method with the same
2502 * parameter types is declared in a class, and one of these methods has a
2503 * return type that is more specific than any of the others, that method is
2504 * returned; otherwise one of the methods is chosen arbitrarily. If the
2505 * name is "<init>"or "<clinit>" a {@code NoSuchMethodException}
2506 * is raised.
2507 *
2508 * <p> If this {@code Class} object represents an array type, then this
2509 * method does not find the {@code clone()} method.
2510 *
2511 * @param name the name of the method
2512 * @param parameterTypes the parameter array
2513 * @return the {@code Method} object for the method of this class
2514 * matching the specified name and parameters
2515 * @throws NoSuchMethodException if a matching method is not found.
2516 * @throws NullPointerException if {@code name} is {@code null}
2517 * @throws SecurityException
2518 * If a security manager, <i>s</i>, is present and any of the
2519 * following conditions is met:
2520 *
2521 * <ul>
2522 *
2523 * <li> the caller's class loader is not the same as the
2524 * class loader of this class and invocation of
2525 * {@link SecurityManager#checkPermission
2526 * s.checkPermission} method with
2527 * {@code RuntimePermission("accessDeclaredMembers")}
2528 * denies access to the declared method
2529 *
2530 * <li> the caller's class loader is not the same as or an
2531 * ancestor of the class loader for the current class and
2532 * invocation of {@link SecurityManager#checkPackageAccess
2533 * s.checkPackageAccess()} denies access to the package
2534 * of this class
2535 *
2536 * </ul>
2537 *
2538 * @jls 8.2 Class Members
2539 * @jls 8.4 Method Declarations
2540 * @since 1.1
2541 */
2542 @CallerSensitive
2543 public Method getDeclaredMethod(String name, Class<?>... parameterTypes)
2544 throws NoSuchMethodException, SecurityException {
2545 Objects.requireNonNull(name);
2546 SecurityManager sm = System.getSecurityManager();
2547 if (sm != null) {
2548 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2549 }
2550 Method method = searchMethods(privateGetDeclaredMethods(false), name, parameterTypes);
2551 if (method == null) {
2552 throw new NoSuchMethodException(methodToString(name, parameterTypes));
2553 }
2554 return getReflectionFactory().copyMethod(method);
2555 }
2556
2557 /**
2558 * Returns the list of {@code Method} objects for the declared public
2559 * methods of this class or interface that have the specified method name
2560 * and parameter types.
2561 *
2562 * @param name the name of the method
2563 * @param parameterTypes the parameter array
2564 * @return the list of {@code Method} objects for the public methods of
2565 * this class matching the specified name and parameters
2566 */
2567 List<Method> getDeclaredPublicMethods(String name, Class<?>... parameterTypes) {
2568 Method[] methods = privateGetDeclaredMethods(/* publicOnly */ true);
2569 ReflectionFactory factory = getReflectionFactory();
2570 List<Method> result = new ArrayList<>();
2571 for (Method method : methods) {
2572 if (method.getName().equals(name)
2573 && Arrays.equals(
2574 factory.getExecutableSharedParameterTypes(method),
2575 parameterTypes)) {
2576 result.add(factory.copyMethod(method));
2577 }
2578 }
2579 return result;
2580 }
2581
2582 /**
2583 * Returns a {@code Constructor} object that reflects the specified
2584 * constructor of the class or interface represented by this
2585 * {@code Class} object. The {@code parameterTypes} parameter is
2586 * an array of {@code Class} objects that identify the constructor's
2587 * formal parameter types, in declared order.
2588 *
2589 * If this {@code Class} object represents an inner class
2590 * declared in a non-static context, the formal parameter types
2591 * include the explicit enclosing instance as the first parameter.
2592 *
2593 * @param parameterTypes the parameter array
2594 * @return The {@code Constructor} object for the constructor with the
2595 * specified parameter list
2596 * @throws NoSuchMethodException if a matching method is not found.
2597 * @throws SecurityException
2598 * If a security manager, <i>s</i>, is present and any of the
2599 * following conditions is met:
2600 *
2601 * <ul>
2602 *
2603 * <li> the caller's class loader is not the same as the
2604 * class loader of this class and invocation of
2605 * {@link SecurityManager#checkPermission
2606 * s.checkPermission} method with
2607 * {@code RuntimePermission("accessDeclaredMembers")}
2608 * denies access to the declared constructor
2609 *
2610 * <li> the caller's class loader is not the same as or an
2611 * ancestor of the class loader for the current class and
2612 * invocation of {@link SecurityManager#checkPackageAccess
2613 * s.checkPackageAccess()} denies access to the package
2614 * of this class
2615 *
2616 * </ul>
2617 *
2618 * @since 1.1
2619 */
2620 @CallerSensitive
2621 public Constructor<T> getDeclaredConstructor(Class<?>... parameterTypes)
2622 throws NoSuchMethodException, SecurityException
2623 {
2624 SecurityManager sm = System.getSecurityManager();
2625 if (sm != null) {
2626 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2627 }
2628
2629 return getReflectionFactory().copyConstructor(
2630 getConstructor0(parameterTypes, Member.DECLARED));
2631 }
2632
2633 /**
2634 * Finds a resource with a given name.
2635 *
2636 * <p> If this class is in a named {@link Module Module} then this method
2637 * will attempt to find the resource in the module. This is done by
2638 * delegating to the module's class loader {@link
2639 * ClassLoader#findResource(String,String) findResource(String,String)}
2640 * method, invoking it with the module name and the absolute name of the
2641 * resource. Resources in named modules are subject to the rules for
2642 * encapsulation specified in the {@code Module} {@link
2643 * Module#getResourceAsStream getResourceAsStream} method and so this
2644 * method returns {@code null} when the resource is a
2645 * non-"{@code .class}" resource in a package that is not open to the
2646 * caller's module.
2647 *
2648 * <p> Otherwise, if this class is not in a named module then the rules for
2649 * searching resources associated with a given class are implemented by the
2650 * defining {@linkplain ClassLoader class loader} of the class. This method
2651 * delegates to this object's class loader. If this object was loaded by
2652 * the bootstrap class loader, the method delegates to {@link
2653 * ClassLoader#getSystemResourceAsStream}.
2654 *
2655 * <p> Before delegation, an absolute resource name is constructed from the
2656 * given resource name using this algorithm:
2657 *
2658 * <ul>
2659 *
2660 * <li> If the {@code name} begins with a {@code '/'}
2661 * (<code>'\u002f'</code>), then the absolute name of the resource is the
2662 * portion of the {@code name} following the {@code '/'}.
2663 *
2664 * <li> Otherwise, the absolute name is of the following form:
2665 *
2666 * <blockquote>
2667 * {@code modified_package_name/name}
2668 * </blockquote>
2669 *
2670 * <p> Where the {@code modified_package_name} is the package name of this
2671 * object with {@code '/'} substituted for {@code '.'}
2672 * (<code>'\u002e'</code>).
2673 *
2674 * </ul>
2675 *
2676 * @param name name of the desired resource
2677 * @return A {@link java.io.InputStream} object; {@code null} if no
2678 * resource with this name is found, the resource is in a package
2679 * that is not {@linkplain Module#isOpen(String, Module) open} to at
2680 * least the caller module, or access to the resource is denied
2681 * by the security manager.
2682 * @throws NullPointerException If {@code name} is {@code null}
2683 *
2684 * @see Module#getResourceAsStream(String)
2685 * @since 1.1
2686 * @revised 9
2687 * @spec JPMS
2688 */
2689 @CallerSensitive
2690 public InputStream getResourceAsStream(String name) {
2691 name = resolveName(name);
2692
2693 Module thisModule = getModule();
2694 if (thisModule.isNamed()) {
2695 // check if resource can be located by caller
2696 if (Resources.canEncapsulate(name)
2697 && !isOpenToCaller(name, Reflection.getCallerClass())) {
2698 return null;
2699 }
2700
2701 // resource not encapsulated or in package open to caller
2702 String mn = thisModule.getName();
2703 ClassLoader cl = getClassLoader0();
2704 try {
2705
2706 // special-case built-in class loaders to avoid the
2707 // need for a URL connection
2708 if (cl == null) {
2709 return BootLoader.findResourceAsStream(mn, name);
2710 } else if (cl instanceof BuiltinClassLoader) {
2711 return ((BuiltinClassLoader) cl).findResourceAsStream(mn, name);
2712 } else {
2713 URL url = cl.findResource(mn, name);
2714 return (url != null) ? url.openStream() : null;
2715 }
2716
2717 } catch (IOException | SecurityException e) {
2718 return null;
2719 }
2720 }
2721
2722 // unnamed module
2723 ClassLoader cl = getClassLoader0();
2724 if (cl == null) {
2725 return ClassLoader.getSystemResourceAsStream(name);
2726 } else {
2727 return cl.getResourceAsStream(name);
2728 }
2729 }
2730
2731 /**
2732 * Finds a resource with a given name.
2733 *
2734 * <p> If this class is in a named {@link Module Module} then this method
2735 * will attempt to find the resource in the module. This is done by
2736 * delegating to the module's class loader {@link
2737 * ClassLoader#findResource(String,String) findResource(String,String)}
2738 * method, invoking it with the module name and the absolute name of the
2739 * resource. Resources in named modules are subject to the rules for
2740 * encapsulation specified in the {@code Module} {@link
2741 * Module#getResourceAsStream getResourceAsStream} method and so this
2742 * method returns {@code null} when the resource is a
2743 * non-"{@code .class}" resource in a package that is not open to the
2744 * caller's module.
2745 *
2746 * <p> Otherwise, if this class is not in a named module then the rules for
2747 * searching resources associated with a given class are implemented by the
2748 * defining {@linkplain ClassLoader class loader} of the class. This method
2749 * delegates to this object's class loader. If this object was loaded by
2750 * the bootstrap class loader, the method delegates to {@link
2751 * ClassLoader#getSystemResource}.
2752 *
2753 * <p> Before delegation, an absolute resource name is constructed from the
2754 * given resource name using this algorithm:
2755 *
2756 * <ul>
2757 *
2758 * <li> If the {@code name} begins with a {@code '/'}
2759 * (<code>'\u002f'</code>), then the absolute name of the resource is the
2760 * portion of the {@code name} following the {@code '/'}.
2761 *
2762 * <li> Otherwise, the absolute name is of the following form:
2763 *
2764 * <blockquote>
2765 * {@code modified_package_name/name}
2766 * </blockquote>
2767 *
2768 * <p> Where the {@code modified_package_name} is the package name of this
2769 * object with {@code '/'} substituted for {@code '.'}
2770 * (<code>'\u002e'</code>).
2771 *
2772 * </ul>
2773 *
2774 * @param name name of the desired resource
2775 * @return A {@link java.net.URL} object; {@code null} if no resource with
2776 * this name is found, the resource cannot be located by a URL, the
2777 * resource is in a package that is not
2778 * {@linkplain Module#isOpen(String, Module) open} to at least the caller
2779 * module, or access to the resource is denied by the security
2780 * manager.
2781 * @throws NullPointerException If {@code name} is {@code null}
2782 * @since 1.1
2783 * @revised 9
2784 * @spec JPMS
2785 */
2786 @CallerSensitive
2787 public URL getResource(String name) {
2788 name = resolveName(name);
2789
2790 Module thisModule = getModule();
2791 if (thisModule.isNamed()) {
2792 // check if resource can be located by caller
2793 if (Resources.canEncapsulate(name)
2794 && !isOpenToCaller(name, Reflection.getCallerClass())) {
2795 return null;
2796 }
2797
2798 // resource not encapsulated or in package open to caller
2799 String mn = thisModule.getName();
2800 ClassLoader cl = getClassLoader0();
2801 try {
2802 if (cl == null) {
2803 return BootLoader.findResource(mn, name);
2804 } else {
2805 return cl.findResource(mn, name);
2806 }
2807 } catch (IOException ioe) {
2808 return null;
2809 }
2810 }
2811
2812 // unnamed module
2813 ClassLoader cl = getClassLoader0();
2814 if (cl == null) {
2815 return ClassLoader.getSystemResource(name);
2816 } else {
2817 return cl.getResource(name);
2818 }
2819 }
2820
2821 /**
2822 * Returns true if a resource with the given name can be located by the
2823 * given caller. All resources in a module can be located by code in
2824 * the module. For other callers, then the package needs to be open to
2825 * the caller.
2826 */
2827 private boolean isOpenToCaller(String name, Class<?> caller) {
2828 // assert getModule().isNamed();
2829 Module thisModule = getModule();
2830 Module callerModule = (caller != null) ? caller.getModule() : null;
2831 if (callerModule != thisModule) {
2832 String pn = Resources.toPackageName(name);
2833 if (thisModule.getDescriptor().packages().contains(pn)) {
2834 if (callerModule == null && !thisModule.isOpen(pn)) {
2835 // no caller, package not open
2836 return false;
2837 }
2838 if (!thisModule.isOpen(pn, callerModule)) {
2839 // package not open to caller
2840 return false;
2841 }
2842 }
2843 }
2844 return true;
2845 }
2846
2847
2848 /** protection domain returned when the internal domain is null */
2849 private static java.security.ProtectionDomain allPermDomain;
2850
2851 /**
2852 * Returns the {@code ProtectionDomain} of this class. If there is a
2853 * security manager installed, this method first calls the security
2854 * manager's {@code checkPermission} method with a
2855 * {@code RuntimePermission("getProtectionDomain")} permission to
2856 * ensure it's ok to get the
2857 * {@code ProtectionDomain}.
2858 *
2859 * @return the ProtectionDomain of this class
2860 *
2861 * @throws SecurityException
2862 * if a security manager exists and its
2863 * {@code checkPermission} method doesn't allow
2864 * getting the ProtectionDomain.
2865 *
2866 * @see java.security.ProtectionDomain
2867 * @see SecurityManager#checkPermission
2868 * @see java.lang.RuntimePermission
2869 * @since 1.2
2870 */
2871 public java.security.ProtectionDomain getProtectionDomain() {
2872 SecurityManager sm = System.getSecurityManager();
2873 if (sm != null) {
2874 sm.checkPermission(SecurityConstants.GET_PD_PERMISSION);
2875 }
2876 java.security.ProtectionDomain pd = getProtectionDomain0();
2877 if (pd == null) {
2878 if (allPermDomain == null) {
2879 java.security.Permissions perms =
2880 new java.security.Permissions();
2881 perms.add(SecurityConstants.ALL_PERMISSION);
2882 allPermDomain =
2883 new java.security.ProtectionDomain(null, perms);
2884 }
2885 pd = allPermDomain;
2886 }
2887 return pd;
2888 }
2889
2890
2891 /**
2892 * Returns the ProtectionDomain of this class.
2893 */
2894 private native java.security.ProtectionDomain getProtectionDomain0();
2895
2896 /*
2897 * Return the Virtual Machine's Class object for the named
2898 * primitive type.
2899 */
2900 static native Class<?> getPrimitiveClass(String name);
2901
2902 /*
2903 * Check if client is allowed to access members. If access is denied,
2904 * throw a SecurityException.
2905 *
2906 * This method also enforces package access.
2907 *
2908 * <p> Default policy: allow all clients access with normal Java access
2909 * control.
2910 *
2911 * <p> NOTE: should only be called if a SecurityManager is installed
2912 */
2913 private void checkMemberAccess(SecurityManager sm, int which,
2914 Class<?> caller, boolean checkProxyInterfaces) {
2915 /* Default policy allows access to all {@link Member#PUBLIC} members,
2916 * as well as access to classes that have the same class loader as the caller.
2917 * In all other cases, it requires RuntimePermission("accessDeclaredMembers")
2918 * permission.
2919 */
2920 final ClassLoader ccl = ClassLoader.getClassLoader(caller);
2921 if (which != Member.PUBLIC) {
2922 final ClassLoader cl = getClassLoader0();
2923 if (ccl != cl) {
2924 sm.checkPermission(SecurityConstants.CHECK_MEMBER_ACCESS_PERMISSION);
2925 }
2926 }
2927 this.checkPackageAccess(sm, ccl, checkProxyInterfaces);
2928 }
2929
2930 /*
2931 * Checks if a client loaded in ClassLoader ccl is allowed to access this
2932 * class under the current package access policy. If access is denied,
2933 * throw a SecurityException.
2934 *
2935 * NOTE: this method should only be called if a SecurityManager is active
2936 */
2937 private void checkPackageAccess(SecurityManager sm, final ClassLoader ccl,
2938 boolean checkProxyInterfaces) {
2939 final ClassLoader cl = getClassLoader0();
2940
2941 if (ReflectUtil.needsPackageAccessCheck(ccl, cl)) {
2942 String pkg = this.getPackageName();
2943 if (pkg != null && !pkg.isEmpty()) {
2944 // skip the package access check on a proxy class in default proxy package
2945 if (!Proxy.isProxyClass(this) || ReflectUtil.isNonPublicProxyClass(this)) {
2946 sm.checkPackageAccess(pkg);
2947 }
2948 }
2949 }
2950 // check package access on the proxy interfaces
2951 if (checkProxyInterfaces && Proxy.isProxyClass(this)) {
2952 ReflectUtil.checkProxyPackageAccess(ccl, this.getInterfaces());
2953 }
2954 }
2955
2956 /**
2957 * Add a package name prefix if the name is not absolute Remove leading "/"
2958 * if name is absolute
2959 */
2960 private String resolveName(String name) {
2961 if (!name.startsWith("/")) {
2962 Class<?> c = this;
2963 while (c.isArray()) {
2964 c = c.getComponentType();
2965 }
2966 String baseName = c.getPackageName();
2967 if (baseName != null && !baseName.isEmpty()) {
2968 name = baseName.replace('.', '/') + "/" + name;
2969 }
2970 } else {
2971 name = name.substring(1);
2972 }
2973 return name;
2974 }
2975
2976 /**
2977 * Atomic operations support.
2978 */
2979 private static class Atomic {
2980 // initialize Unsafe machinery here, since we need to call Class.class instance method
2981 // and have to avoid calling it in the static initializer of the Class class...
2982 private static final Unsafe unsafe = Unsafe.getUnsafe();
2983 // offset of Class.reflectionData instance field
2984 private static final long reflectionDataOffset
2985 = unsafe.objectFieldOffset(Class.class, "reflectionData");
2986 // offset of Class.annotationType instance field
2987 private static final long annotationTypeOffset
2988 = unsafe.objectFieldOffset(Class.class, "annotationType");
2989 // offset of Class.annotationData instance field
2990 private static final long annotationDataOffset
2991 = unsafe.objectFieldOffset(Class.class, "annotationData");
2992
2993 static <T> boolean casReflectionData(Class<?> clazz,
2994 SoftReference<ReflectionData<T>> oldData,
2995 SoftReference<ReflectionData<T>> newData) {
2996 return unsafe.compareAndSetReference(clazz, reflectionDataOffset, oldData, newData);
2997 }
2998
2999 static <T> boolean casAnnotationType(Class<?> clazz,
3000 AnnotationType oldType,
3001 AnnotationType newType) {
3002 return unsafe.compareAndSetReference(clazz, annotationTypeOffset, oldType, newType);
3003 }
3004
3005 static <T> boolean casAnnotationData(Class<?> clazz,
3006 AnnotationData oldData,
3007 AnnotationData newData) {
3008 return unsafe.compareAndSetReference(clazz, annotationDataOffset, oldData, newData);
3009 }
3010 }
3011
3012 /**
3013 * Reflection support.
3014 */
3015
3016 // Reflection data caches various derived names and reflective members. Cached
3017 // values may be invalidated when JVM TI RedefineClasses() is called
3018 private static class ReflectionData<T> {
3019 volatile Field[] declaredFields;
3020 volatile Field[] publicFields;
3021 volatile Method[] declaredMethods;
3022 volatile Method[] publicMethods;
3023 volatile Constructor<T>[] declaredConstructors;
3024 volatile Constructor<T>[] publicConstructors;
3025 // Intermediate results for getFields and getMethods
3026 volatile Field[] declaredPublicFields;
3027 volatile Method[] declaredPublicMethods;
3028 volatile Class<?>[] interfaces;
3029
3030 // Cached names
3031 String simpleName;
3032 String canonicalName;
3033 static final String NULL_SENTINEL = new String();
3034
3035 // Value of classRedefinedCount when we created this ReflectionData instance
3036 final int redefinedCount;
3037
3038 ReflectionData(int redefinedCount) {
3039 this.redefinedCount = redefinedCount;
3040 }
3041 }
3042
3043 private transient volatile SoftReference<ReflectionData<T>> reflectionData;
3044
3045 // Incremented by the VM on each call to JVM TI RedefineClasses()
3046 // that redefines this class or a superclass.
3047 private transient volatile int classRedefinedCount;
3048
3049 // Lazily create and cache ReflectionData
3050 private ReflectionData<T> reflectionData() {
3051 SoftReference<ReflectionData<T>> reflectionData = this.reflectionData;
3052 int classRedefinedCount = this.classRedefinedCount;
3053 ReflectionData<T> rd;
3054 if (reflectionData != null &&
3055 (rd = reflectionData.get()) != null &&
3056 rd.redefinedCount == classRedefinedCount) {
3057 return rd;
3058 }
3059 // else no SoftReference or cleared SoftReference or stale ReflectionData
3060 // -> create and replace new instance
3061 return newReflectionData(reflectionData, classRedefinedCount);
3062 }
3063
3064 private ReflectionData<T> newReflectionData(SoftReference<ReflectionData<T>> oldReflectionData,
3065 int classRedefinedCount) {
3066 while (true) {
3067 ReflectionData<T> rd = new ReflectionData<>(classRedefinedCount);
3068 // try to CAS it...
3069 if (Atomic.casReflectionData(this, oldReflectionData, new SoftReference<>(rd))) {
3070 return rd;
3071 }
3072 // else retry
3073 oldReflectionData = this.reflectionData;
3074 classRedefinedCount = this.classRedefinedCount;
3075 if (oldReflectionData != null &&
3076 (rd = oldReflectionData.get()) != null &&
3077 rd.redefinedCount == classRedefinedCount) {
3078 return rd;
3079 }
3080 }
3081 }
3082
3083 // Generic signature handling
3084 private native String getGenericSignature0();
3085
3086 // Generic info repository; lazily initialized
3087 private transient volatile ClassRepository genericInfo;
3088
3089 // accessor for factory
3090 private GenericsFactory getFactory() {
3091 // create scope and factory
3092 return CoreReflectionFactory.make(this, ClassScope.make(this));
3093 }
3094
3095 // accessor for generic info repository;
3096 // generic info is lazily initialized
3097 private ClassRepository getGenericInfo() {
3098 ClassRepository genericInfo = this.genericInfo;
3099 if (genericInfo == null) {
3100 String signature = getGenericSignature0();
3101 if (signature == null) {
3102 genericInfo = ClassRepository.NONE;
3103 } else {
3104 genericInfo = ClassRepository.make(signature, getFactory());
3105 }
3106 this.genericInfo = genericInfo;
3107 }
3108 return (genericInfo != ClassRepository.NONE) ? genericInfo : null;
3109 }
3110
3111 // Annotations handling
3112 native byte[] getRawAnnotations();
3113 // Since 1.8
3114 native byte[] getRawTypeAnnotations();
3115 static byte[] getExecutableTypeAnnotationBytes(Executable ex) {
3116 return getReflectionFactory().getExecutableTypeAnnotationBytes(ex);
3117 }
3118
3119 native ConstantPool getConstantPool();
3120
3121 //
3122 //
3123 // java.lang.reflect.Field handling
3124 //
3125 //
3126
3127 // Returns an array of "root" fields. These Field objects must NOT
3128 // be propagated to the outside world, but must instead be copied
3129 // via ReflectionFactory.copyField.
3130 private Field[] privateGetDeclaredFields(boolean publicOnly) {
3131 Field[] res;
3132 ReflectionData<T> rd = reflectionData();
3133 if (rd != null) {
3134 res = publicOnly ? rd.declaredPublicFields : rd.declaredFields;
3135 if (res != null) return res;
3136 }
3137 // No cached value available; request value from VM
3138 res = Reflection.filterFields(this, getDeclaredFields0(publicOnly));
3139 if (rd != null) {
3140 if (publicOnly) {
3141 rd.declaredPublicFields = res;
3142 } else {
3143 rd.declaredFields = res;
3144 }
3145 }
3146 return res;
3147 }
3148
3149 // Returns an array of "root" fields. These Field objects must NOT
3150 // be propagated to the outside world, but must instead be copied
3151 // via ReflectionFactory.copyField.
3152 private Field[] privateGetPublicFields() {
3153 Field[] res;
3154 ReflectionData<T> rd = reflectionData();
3155 if (rd != null) {
3156 res = rd.publicFields;
3157 if (res != null) return res;
3158 }
3159
3160 // Use a linked hash set to ensure order is preserved and
3161 // fields from common super interfaces are not duplicated
3162 LinkedHashSet<Field> fields = new LinkedHashSet<>();
3163
3164 // Local fields
3165 addAll(fields, privateGetDeclaredFields(true));
3166
3167 // Direct superinterfaces, recursively
3168 for (Class<?> si : getInterfaces()) {
3169 addAll(fields, si.privateGetPublicFields());
3170 }
3171
3172 // Direct superclass, recursively
3173 Class<?> sc = getSuperclass();
3174 if (sc != null) {
3175 addAll(fields, sc.privateGetPublicFields());
3176 }
3177
3178 res = fields.toArray(new Field[0]);
3179 if (rd != null) {
3180 rd.publicFields = res;
3181 }
3182 return res;
3183 }
3184
3185 private static void addAll(Collection<Field> c, Field[] o) {
3186 for (Field f : o) {
3187 c.add(f);
3188 }
3189 }
3190
3191
3192 //
3193 //
3194 // java.lang.reflect.Constructor handling
3195 //
3196 //
3197
3198 // Returns an array of "root" constructors. These Constructor
3199 // objects must NOT be propagated to the outside world, but must
3200 // instead be copied via ReflectionFactory.copyConstructor.
3201 private Constructor<T>[] privateGetDeclaredConstructors(boolean publicOnly) {
3202 Constructor<T>[] res;
3203 ReflectionData<T> rd = reflectionData();
3204 if (rd != null) {
3205 res = publicOnly ? rd.publicConstructors : rd.declaredConstructors;
3206 if (res != null) return res;
3207 }
3208 // No cached value available; request value from VM
3209 if (isInterface()) {
3210 @SuppressWarnings("unchecked")
3211 Constructor<T>[] temporaryRes = (Constructor<T>[]) new Constructor<?>[0];
3212 res = temporaryRes;
3213 } else {
3214 res = getDeclaredConstructors0(publicOnly);
3215 }
3216 if (rd != null) {
3217 if (publicOnly) {
3218 rd.publicConstructors = res;
3219 } else {
3220 rd.declaredConstructors = res;
3221 }
3222 }
3223 return res;
3224 }
3225
3226 //
3227 //
3228 // java.lang.reflect.Method handling
3229 //
3230 //
3231
3232 // Returns an array of "root" methods. These Method objects must NOT
3233 // be propagated to the outside world, but must instead be copied
3234 // via ReflectionFactory.copyMethod.
3235 private Method[] privateGetDeclaredMethods(boolean publicOnly) {
3236 Method[] res;
3237 ReflectionData<T> rd = reflectionData();
3238 if (rd != null) {
3239 res = publicOnly ? rd.declaredPublicMethods : rd.declaredMethods;
3240 if (res != null) return res;
3241 }
3242 // No cached value available; request value from VM
3243 res = Reflection.filterMethods(this, getDeclaredMethods0(publicOnly));
3244 if (rd != null) {
3245 if (publicOnly) {
3246 rd.declaredPublicMethods = res;
3247 } else {
3248 rd.declaredMethods = res;
3249 }
3250 }
3251 return res;
3252 }
3253
3254 // Returns an array of "root" methods. These Method objects must NOT
3255 // be propagated to the outside world, but must instead be copied
3256 // via ReflectionFactory.copyMethod.
3257 private Method[] privateGetPublicMethods() {
3258 Method[] res;
3259 ReflectionData<T> rd = reflectionData();
3260 if (rd != null) {
3261 res = rd.publicMethods;
3262 if (res != null) return res;
3263 }
3264
3265 // No cached value available; compute value recursively.
3266 // Start by fetching public declared methods...
3267 PublicMethods pms = new PublicMethods();
3268 for (Method m : privateGetDeclaredMethods(/* publicOnly */ true)) {
3269 pms.merge(m);
3270 }
3271 // ...then recur over superclass methods...
3272 Class<?> sc = getSuperclass();
3273 if (sc != null) {
3274 for (Method m : sc.privateGetPublicMethods()) {
3275 pms.merge(m);
3276 }
3277 }
3278 // ...and finally over direct superinterfaces.
3279 for (Class<?> intf : getInterfaces(/* cloneArray */ false)) {
3280 for (Method m : intf.privateGetPublicMethods()) {
3281 // static interface methods are not inherited
3282 if (!Modifier.isStatic(m.getModifiers())) {
3283 pms.merge(m);
3284 }
3285 }
3286 }
3287
3288 res = pms.toArray();
3289 if (rd != null) {
3290 rd.publicMethods = res;
3291 }
3292 return res;
3293 }
3294
3295
3296 //
3297 // Helpers for fetchers of one field, method, or constructor
3298 //
3299
3300 // This method does not copy the returned Field object!
3301 private static Field searchFields(Field[] fields, String name) {
3302 for (Field field : fields) {
3303 if (field.getName().equals(name)) {
3304 return field;
3305 }
3306 }
3307 return null;
3308 }
3309
3310 // Returns a "root" Field object. This Field object must NOT
3311 // be propagated to the outside world, but must instead be copied
3312 // via ReflectionFactory.copyField.
3313 private Field getField0(String name) {
3314 // Note: the intent is that the search algorithm this routine
3315 // uses be equivalent to the ordering imposed by
3316 // privateGetPublicFields(). It fetches only the declared
3317 // public fields for each class, however, to reduce the number
3318 // of Field objects which have to be created for the common
3319 // case where the field being requested is declared in the
3320 // class which is being queried.
3321 Field res;
3322 // Search declared public fields
3323 if ((res = searchFields(privateGetDeclaredFields(true), name)) != null) {
3324 return res;
3325 }
3326 // Direct superinterfaces, recursively
3327 Class<?>[] interfaces = getInterfaces(/* cloneArray */ false);
3328 for (Class<?> c : interfaces) {
3329 if ((res = c.getField0(name)) != null) {
3330 return res;
3331 }
3332 }
3333 // Direct superclass, recursively
3334 if (!isInterface()) {
3335 Class<?> c = getSuperclass();
3336 if (c != null) {
3337 if ((res = c.getField0(name)) != null) {
3338 return res;
3339 }
3340 }
3341 }
3342 return null;
3343 }
3344
3345 // This method does not copy the returned Method object!
3346 private static Method searchMethods(Method[] methods,
3347 String name,
3348 Class<?>[] parameterTypes)
3349 {
3350 ReflectionFactory fact = getReflectionFactory();
3351 Method res = null;
3352 for (Method m : methods) {
3353 if (m.getName().equals(name)
3354 && arrayContentsEq(parameterTypes,
3355 fact.getExecutableSharedParameterTypes(m))
3356 && (res == null
3357 || (res.getReturnType() != m.getReturnType()
3358 && res.getReturnType().isAssignableFrom(m.getReturnType()))))
3359 res = m;
3360 }
3361 return res;
3362 }
3363
3364 private static final Class<?>[] EMPTY_CLASS_ARRAY = new Class<?>[0];
3365
3366 // Returns a "root" Method object. This Method object must NOT
3367 // be propagated to the outside world, but must instead be copied
3368 // via ReflectionFactory.copyMethod.
3369 private Method getMethod0(String name, Class<?>[] parameterTypes) {
3370 PublicMethods.MethodList res = getMethodsRecursive(
3371 name,
3372 parameterTypes == null ? EMPTY_CLASS_ARRAY : parameterTypes,
3373 /* includeStatic */ true);
3374 return res == null ? null : res.getMostSpecific();
3375 }
3376
3377 // Returns a list of "root" Method objects. These Method objects must NOT
3378 // be propagated to the outside world, but must instead be copied
3379 // via ReflectionFactory.copyMethod.
3380 private PublicMethods.MethodList getMethodsRecursive(String name,
3381 Class<?>[] parameterTypes,
3382 boolean includeStatic) {
3383 // 1st check declared public methods
3384 Method[] methods = privateGetDeclaredMethods(/* publicOnly */ true);
3385 PublicMethods.MethodList res = PublicMethods.MethodList
3386 .filter(methods, name, parameterTypes, includeStatic);
3387 // if there is at least one match among declared methods, we need not
3388 // search any further as such match surely overrides matching methods
3389 // declared in superclass(es) or interface(s).
3390 if (res != null) {
3391 return res;
3392 }
3393
3394 // if there was no match among declared methods,
3395 // we must consult the superclass (if any) recursively...
3396 Class<?> sc = getSuperclass();
3397 if (sc != null) {
3398 res = sc.getMethodsRecursive(name, parameterTypes, includeStatic);
3399 }
3400
3401 // ...and coalesce the superclass methods with methods obtained
3402 // from directly implemented interfaces excluding static methods...
3403 for (Class<?> intf : getInterfaces(/* cloneArray */ false)) {
3404 res = PublicMethods.MethodList.merge(
3405 res, intf.getMethodsRecursive(name, parameterTypes,
3406 /* includeStatic */ false));
3407 }
3408
3409 return res;
3410 }
3411
3412 // Returns a "root" Constructor object. This Constructor object must NOT
3413 // be propagated to the outside world, but must instead be copied
3414 // via ReflectionFactory.copyConstructor.
3415 private Constructor<T> getConstructor0(Class<?>[] parameterTypes,
3416 int which) throws NoSuchMethodException
3417 {
3418 ReflectionFactory fact = getReflectionFactory();
3419 Constructor<T>[] constructors = privateGetDeclaredConstructors((which == Member.PUBLIC));
3420 for (Constructor<T> constructor : constructors) {
3421 if (arrayContentsEq(parameterTypes,
3422 fact.getExecutableSharedParameterTypes(constructor))) {
3423 return constructor;
3424 }
3425 }
3426 throw new NoSuchMethodException(methodToString("<init>", parameterTypes));
3427 }
3428
3429 //
3430 // Other helpers and base implementation
3431 //
3432
3433 private static boolean arrayContentsEq(Object[] a1, Object[] a2) {
3434 if (a1 == null) {
3435 return a2 == null || a2.length == 0;
3436 }
3437
3438 if (a2 == null) {
3439 return a1.length == 0;
3440 }
3441
3442 if (a1.length != a2.length) {
3443 return false;
3444 }
3445
3446 for (int i = 0; i < a1.length; i++) {
3447 if (a1[i] != a2[i]) {
3448 return false;
3449 }
3450 }
3451
3452 return true;
3453 }
3454
3455 private static Field[] copyFields(Field[] arg) {
3456 Field[] out = new Field[arg.length];
3457 ReflectionFactory fact = getReflectionFactory();
3458 for (int i = 0; i < arg.length; i++) {
3459 out[i] = fact.copyField(arg[i]);
3460 }
3461 return out;
3462 }
3463
3464 private static Method[] copyMethods(Method[] arg) {
3465 Method[] out = new Method[arg.length];
3466 ReflectionFactory fact = getReflectionFactory();
3467 for (int i = 0; i < arg.length; i++) {
3468 out[i] = fact.copyMethod(arg[i]);
3469 }
3470 return out;
3471 }
3472
3473 private static <U> Constructor<U>[] copyConstructors(Constructor<U>[] arg) {
3474 Constructor<U>[] out = arg.clone();
3475 ReflectionFactory fact = getReflectionFactory();
3476 for (int i = 0; i < out.length; i++) {
3477 out[i] = fact.copyConstructor(out[i]);
3478 }
3479 return out;
3480 }
3481
3482 private native Field[] getDeclaredFields0(boolean publicOnly);
3483 private native Method[] getDeclaredMethods0(boolean publicOnly);
3484 private native Constructor<T>[] getDeclaredConstructors0(boolean publicOnly);
3485 private native Class<?>[] getDeclaredClasses0();
3486 private native Object[] getRecordComponents0();
3487 private native boolean isRecord0();
3488
3489 /**
3490 * Helper method to get the method name from arguments.
3491 */
3492 private String methodToString(String name, Class<?>[] argTypes) {
3493 return getName() + '.' + name +
3494 ((argTypes == null || argTypes.length == 0) ?
3495 "()" :
3496 Arrays.stream(argTypes)
3497 .map(c -> c == null ? "null" : c.getName())
3498 .collect(Collectors.joining(",", "(", ")")));
3499 }
3500
3501 /** use serialVersionUID from JDK 1.1 for interoperability */
3502 @java.io.Serial
3503 private static final long serialVersionUID = 3206093459760846163L;
3504
3505
3506 /**
3507 * Class Class is special cased within the Serialization Stream Protocol.
3508 *
3509 * A Class instance is written initially into an ObjectOutputStream in the
3510 * following format:
3511 * <pre>
3512 * {@code TC_CLASS} ClassDescriptor
3513 * A ClassDescriptor is a special cased serialization of
3514 * a {@code java.io.ObjectStreamClass} instance.
3515 * </pre>
3516 * A new handle is generated for the initial time the class descriptor
3517 * is written into the stream. Future references to the class descriptor
3518 * are written as references to the initial class descriptor instance.
3519 *
3520 * @see java.io.ObjectStreamClass
3521 */
3522 @java.io.Serial
3523 private static final ObjectStreamField[] serialPersistentFields =
3524 new ObjectStreamField[0];
3525
3526
3527 /**
3528 * Returns the assertion status that would be assigned to this
3529 * class if it were to be initialized at the time this method is invoked.
3530 * If this class has had its assertion status set, the most recent
3531 * setting will be returned; otherwise, if any package default assertion
3532 * status pertains to this class, the most recent setting for the most
3533 * specific pertinent package default assertion status is returned;
3534 * otherwise, if this class is not a system class (i.e., it has a
3535 * class loader) its class loader's default assertion status is returned;
3536 * otherwise, the system class default assertion status is returned.
3537 * <p>
3538 * Few programmers will have any need for this method; it is provided
3539 * for the benefit of the JRE itself. (It allows a class to determine at
3540 * the time that it is initialized whether assertions should be enabled.)
3541 * Note that this method is not guaranteed to return the actual
3542 * assertion status that was (or will be) associated with the specified
3543 * class when it was (or will be) initialized.
3544 *
3545 * @return the desired assertion status of the specified class.
3546 * @see java.lang.ClassLoader#setClassAssertionStatus
3547 * @see java.lang.ClassLoader#setPackageAssertionStatus
3548 * @see java.lang.ClassLoader#setDefaultAssertionStatus
3549 * @since 1.4
3550 */
3551 public boolean desiredAssertionStatus() {
3552 ClassLoader loader = getClassLoader0();
3553 // If the loader is null this is a system class, so ask the VM
3554 if (loader == null)
3555 return desiredAssertionStatus0(this);
3556
3557 // If the classloader has been initialized with the assertion
3558 // directives, ask it. Otherwise, ask the VM.
3559 synchronized(loader.assertionLock) {
3560 if (loader.classAssertionStatus != null) {
3561 return loader.desiredAssertionStatus(getName());
3562 }
3563 }
3564 return desiredAssertionStatus0(this);
3565 }
3566
3567 // Retrieves the desired assertion status of this class from the VM
3568 private static native boolean desiredAssertionStatus0(Class<?> clazz);
3569
3570 /**
3571 * Returns true if and only if this class was declared as an enum in the
3572 * source code.
3573 *
3574 * Note that {@link java.lang.Enum} is not itself an enum type.
3575 *
3576 * Also note that if an enum constant is declared with a class body,
3577 * the class of that enum constant object is an anonymous class
3578 * and <em>not</em> the class of the declaring enum type. The
3579 * {@link Enum#getDeclaringClass} method of an enum constant can
3580 * be used to get the class of the enum type declaring the
3581 * constant.
3582 *
3583 * @return true if and only if this class was declared as an enum in the
3584 * source code
3585 * @since 1.5
3586 * @jls 8.9.1 Enum Constants
3587 */
3588 public boolean isEnum() {
3589 // An enum must both directly extend java.lang.Enum and have
3590 // the ENUM bit set; classes for specialized enum constants
3591 // don't do the former.
3592 return (this.getModifiers() & ENUM) != 0 &&
3593 this.getSuperclass() == java.lang.Enum.class;
3594 }
3595
3596 /**
3597 * {@preview Associated with records, a preview feature of the Java language.
3598 *
3599 * This method is associated with <i>records</i>, a preview
3600 * feature of the Java language. Preview features
3601 * may be removed in a future release, or upgraded to permanent
3602 * features of the Java language.}
3603 *
3604 * Returns {@code true} if and only if this class is a record class.
3605 * It returns {@code false} otherwise. Note that class {@link Record} is not a
3606 * record type and thus invoking this method on class {@link java.lang.Record}
3607 * returns {@code false}.
3608 *
3609 * @return true if and only if this class is a record class
3610 * @jls 8.10 Record Types
3611 * @since 14
3612 */
3613 @jdk.internal.PreviewFeature(feature=jdk.internal.PreviewFeature.Feature.RECORDS,
3614 essentialAPI=false)
3615 public boolean isRecord() {
3616 return isRecord0();
3617 }
3618
3619 // Fetches the factory for reflective objects
3620 private static ReflectionFactory getReflectionFactory() {
3621 if (reflectionFactory == null) {
3622 reflectionFactory =
3623 java.security.AccessController.doPrivileged
3624 (new ReflectionFactory.GetReflectionFactoryAction());
3625 }
3626 return reflectionFactory;
3627 }
3628 private static ReflectionFactory reflectionFactory;
3629
3630 /**
3631 * Returns the elements of this enum class or null if this
3632 * Class object does not represent an enum type.
3633 *
3634 * @return an array containing the values comprising the enum class
3635 * represented by this Class object in the order they're
3636 * declared, or null if this Class object does not
3637 * represent an enum type
3638 * @since 1.5
3639 */
3640 public T[] getEnumConstants() {
3641 T[] values = getEnumConstantsShared();
3642 return (values != null) ? values.clone() : null;
3643 }
3644
3645 /**
3646 * Returns the elements of this enum class or null if this
3647 * Class object does not represent an enum type;
3648 * identical to getEnumConstants except that the result is
3649 * uncloned, cached, and shared by all callers.
3650 */
3651 T[] getEnumConstantsShared() {
3652 T[] constants = enumConstants;
3653 if (constants == null) {
3654 if (!isEnum()) return null;
3655 try {
3656 final Method values = getMethod("values");
3657 java.security.AccessController.doPrivileged(
3658 new java.security.PrivilegedAction<>() {
3659 public Void run() {
3660 values.setAccessible(true);
3661 return null;
3662 }
3663 });
3664 @SuppressWarnings("unchecked")
3665 T[] temporaryConstants = (T[])values.invoke(null);
3666 enumConstants = constants = temporaryConstants;
3667 }
3668 // These can happen when users concoct enum-like classes
3669 // that don't comply with the enum spec.
3670 catch (InvocationTargetException | NoSuchMethodException |
3671 IllegalAccessException ex) { return null; }
3672 }
3673 return constants;
3674 }
3675 private transient volatile T[] enumConstants;
3676
3677 /**
3678 * Returns a map from simple name to enum constant. This package-private
3679 * method is used internally by Enum to implement
3680 * {@code public static <T extends Enum<T>> T valueOf(Class<T>, String)}
3681 * efficiently. Note that the map is returned by this method is
3682 * created lazily on first use. Typically it won't ever get created.
3683 */
3684 Map<String, T> enumConstantDirectory() {
3685 Map<String, T> directory = enumConstantDirectory;
3686 if (directory == null) {
3687 T[] universe = getEnumConstantsShared();
3688 if (universe == null)
3689 throw new IllegalArgumentException(
3690 getName() + " is not an enum type");
3691 directory = new HashMap<>((int)(universe.length / 0.75f) + 1);
3692 for (T constant : universe) {
3693 directory.put(((Enum<?>)constant).name(), constant);
3694 }
3695 enumConstantDirectory = directory;
3696 }
3697 return directory;
3698 }
3699 private transient volatile Map<String, T> enumConstantDirectory;
3700
3701 /**
3702 * Casts an object to the class or interface represented
3703 * by this {@code Class} object.
3704 *
3705 * @param obj the object to be cast
3706 * @return the object after casting, or null if obj is null
3707 *
3708 * @throws ClassCastException if the object is not
3709 * null and is not assignable to the type T.
3710 *
3711 * @since 1.5
3712 */
3713 @SuppressWarnings("unchecked")
3714 @HotSpotIntrinsicCandidate
3715 public T cast(Object obj) {
3716 if (obj != null && !isInstance(obj))
3717 throw new ClassCastException(cannotCastMsg(obj));
3718 return (T) obj;
3719 }
3720
3721 private String cannotCastMsg(Object obj) {
3722 return "Cannot cast " + obj.getClass().getName() + " to " + getName();
3723 }
3724
3725 /**
3726 * Casts this {@code Class} object to represent a subclass of the class
3727 * represented by the specified class object. Checks that the cast
3728 * is valid, and throws a {@code ClassCastException} if it is not. If
3729 * this method succeeds, it always returns a reference to this class object.
3730 *
3731 * <p>This method is useful when a client needs to "narrow" the type of
3732 * a {@code Class} object to pass it to an API that restricts the
3733 * {@code Class} objects that it is willing to accept. A cast would
3734 * generate a compile-time warning, as the correctness of the cast
3735 * could not be checked at runtime (because generic types are implemented
3736 * by erasure).
3737 *
3738 * @param <U> the type to cast this class object to
3739 * @param clazz the class of the type to cast this class object to
3740 * @return this {@code Class} object, cast to represent a subclass of
3741 * the specified class object.
3742 * @throws ClassCastException if this {@code Class} object does not
3743 * represent a subclass of the specified class (here "subclass" includes
3744 * the class itself).
3745 * @since 1.5
3746 */
3747 @SuppressWarnings("unchecked")
3748 public <U> Class<? extends U> asSubclass(Class<U> clazz) {
3749 if (clazz.isAssignableFrom(this))
3750 return (Class<? extends U>) this;
3751 else
3752 throw new ClassCastException(this.toString());
3753 }
3754
3755 /**
3756 * @throws NullPointerException {@inheritDoc}
3757 * @since 1.5
3758 */
3759 @SuppressWarnings("unchecked")
3760 public <A extends Annotation> A getAnnotation(Class<A> annotationClass) {
3761 Objects.requireNonNull(annotationClass);
3762
3763 return (A) annotationData().annotations.get(annotationClass);
3764 }
3765
3766 /**
3767 * {@inheritDoc}
3768 * @throws NullPointerException {@inheritDoc}
3769 * @since 1.5
3770 */
3771 @Override
3772 public boolean isAnnotationPresent(Class<? extends Annotation> annotationClass) {
3773 return GenericDeclaration.super.isAnnotationPresent(annotationClass);
3774 }
3775
3776 /**
3777 * @throws NullPointerException {@inheritDoc}
3778 * @since 1.8
3779 */
3780 @Override
3781 public <A extends Annotation> A[] getAnnotationsByType(Class<A> annotationClass) {
3782 Objects.requireNonNull(annotationClass);
3783
3784 AnnotationData annotationData = annotationData();
3785 return AnnotationSupport.getAssociatedAnnotations(annotationData.declaredAnnotations,
3786 this,
3787 annotationClass);
3788 }
3789
3790 /**
3791 * @since 1.5
3792 */
3793 public Annotation[] getAnnotations() {
3794 return AnnotationParser.toArray(annotationData().annotations);
3795 }
3796
3797 /**
3798 * @throws NullPointerException {@inheritDoc}
3799 * @since 1.8
3800 */
3801 @Override
3802 @SuppressWarnings("unchecked")
3803 public <A extends Annotation> A getDeclaredAnnotation(Class<A> annotationClass) {
3804 Objects.requireNonNull(annotationClass);
3805
3806 return (A) annotationData().declaredAnnotations.get(annotationClass);
3807 }
3808
3809 /**
3810 * @throws NullPointerException {@inheritDoc}
3811 * @since 1.8
3812 */
3813 @Override
3814 public <A extends Annotation> A[] getDeclaredAnnotationsByType(Class<A> annotationClass) {
3815 Objects.requireNonNull(annotationClass);
3816
3817 return AnnotationSupport.getDirectlyAndIndirectlyPresent(annotationData().declaredAnnotations,
3818 annotationClass);
3819 }
3820
3821 /**
3822 * @since 1.5
3823 */
3824 public Annotation[] getDeclaredAnnotations() {
3825 return AnnotationParser.toArray(annotationData().declaredAnnotations);
3826 }
3827
3828 // annotation data that might get invalidated when JVM TI RedefineClasses() is called
3829 private static class AnnotationData {
3830 final Map<Class<? extends Annotation>, Annotation> annotations;
3831 final Map<Class<? extends Annotation>, Annotation> declaredAnnotations;
3832
3833 // Value of classRedefinedCount when we created this AnnotationData instance
3834 final int redefinedCount;
3835
3836 AnnotationData(Map<Class<? extends Annotation>, Annotation> annotations,
3837 Map<Class<? extends Annotation>, Annotation> declaredAnnotations,
3838 int redefinedCount) {
3839 this.annotations = annotations;
3840 this.declaredAnnotations = declaredAnnotations;
3841 this.redefinedCount = redefinedCount;
3842 }
3843 }
3844
3845 // Annotations cache
3846 @SuppressWarnings("UnusedDeclaration")
3847 private transient volatile AnnotationData annotationData;
3848
3849 private AnnotationData annotationData() {
3850 while (true) { // retry loop
3851 AnnotationData annotationData = this.annotationData;
3852 int classRedefinedCount = this.classRedefinedCount;
3853 if (annotationData != null &&
3854 annotationData.redefinedCount == classRedefinedCount) {
3855 return annotationData;
3856 }
3857 // null or stale annotationData -> optimistically create new instance
3858 AnnotationData newAnnotationData = createAnnotationData(classRedefinedCount);
3859 // try to install it
3860 if (Atomic.casAnnotationData(this, annotationData, newAnnotationData)) {
3861 // successfully installed new AnnotationData
3862 return newAnnotationData;
3863 }
3864 }
3865 }
3866
3867 private AnnotationData createAnnotationData(int classRedefinedCount) {
3868 Map<Class<? extends Annotation>, Annotation> declaredAnnotations =
3869 AnnotationParser.parseAnnotations(getRawAnnotations(), getConstantPool(), this);
3870 Class<?> superClass = getSuperclass();
3871 Map<Class<? extends Annotation>, Annotation> annotations = null;
3872 if (superClass != null) {
3873 Map<Class<? extends Annotation>, Annotation> superAnnotations =
3874 superClass.annotationData().annotations;
3875 for (Map.Entry<Class<? extends Annotation>, Annotation> e : superAnnotations.entrySet()) {
3876 Class<? extends Annotation> annotationClass = e.getKey();
3877 if (AnnotationType.getInstance(annotationClass).isInherited()) {
3878 if (annotations == null) { // lazy construction
3879 annotations = new LinkedHashMap<>((Math.max(
3880 declaredAnnotations.size(),
3881 Math.min(12, declaredAnnotations.size() + superAnnotations.size())
3882 ) * 4 + 2) / 3
3883 );
3884 }
3885 annotations.put(annotationClass, e.getValue());
3886 }
3887 }
3888 }
3889 if (annotations == null) {
3890 // no inherited annotations -> share the Map with declaredAnnotations
3891 annotations = declaredAnnotations;
3892 } else {
3893 // at least one inherited annotation -> declared may override inherited
3894 annotations.putAll(declaredAnnotations);
3895 }
3896 return new AnnotationData(annotations, declaredAnnotations, classRedefinedCount);
3897 }
3898
3899 // Annotation types cache their internal (AnnotationType) form
3900
3901 @SuppressWarnings("UnusedDeclaration")
3902 private transient volatile AnnotationType annotationType;
3903
3904 boolean casAnnotationType(AnnotationType oldType, AnnotationType newType) {
3905 return Atomic.casAnnotationType(this, oldType, newType);
3906 }
3907
3908 AnnotationType getAnnotationType() {
3909 return annotationType;
3910 }
3911
3912 Map<Class<? extends Annotation>, Annotation> getDeclaredAnnotationMap() {
3913 return annotationData().declaredAnnotations;
3914 }
3915
3916 /* Backing store of user-defined values pertaining to this class.
3917 * Maintained by the ClassValue class.
3918 */
3919 transient ClassValue.ClassValueMap classValueMap;
3920
3921 /**
3922 * Returns an {@code AnnotatedType} object that represents the use of a
3923 * type to specify the superclass of the entity represented by this {@code
3924 * Class} object. (The <em>use</em> of type Foo to specify the superclass
3925 * in '... extends Foo' is distinct from the <em>declaration</em> of type
3926 * Foo.)
3927 *
3928 * <p> If this {@code Class} object represents a type whose declaration
3929 * does not explicitly indicate an annotated superclass, then the return
3930 * value is an {@code AnnotatedType} object representing an element with no
3931 * annotations.
3932 *
3933 * <p> If this {@code Class} represents either the {@code Object} class, an
3934 * interface type, an array type, a primitive type, or void, the return
3935 * value is {@code null}.
3936 *
3937 * @return an object representing the superclass
3938 * @since 1.8
3939 */
3940 public AnnotatedType getAnnotatedSuperclass() {
3941 if (this == Object.class ||
3942 isInterface() ||
3943 isArray() ||
3944 isPrimitive() ||
3945 this == Void.TYPE) {
3946 return null;
3947 }
3948
3949 return TypeAnnotationParser.buildAnnotatedSuperclass(getRawTypeAnnotations(), getConstantPool(), this);
3950 }
3951
3952 /**
3953 * Returns an array of {@code AnnotatedType} objects that represent the use
3954 * of types to specify superinterfaces of the entity represented by this
3955 * {@code Class} object. (The <em>use</em> of type Foo to specify a
3956 * superinterface in '... implements Foo' is distinct from the
3957 * <em>declaration</em> of type Foo.)
3958 *
3959 * <p> If this {@code Class} object represents a class, the return value is
3960 * an array containing objects representing the uses of interface types to
3961 * specify interfaces implemented by the class. The order of the objects in
3962 * the array corresponds to the order of the interface types used in the
3963 * 'implements' clause of the declaration of this {@code Class} object.
3964 *
3965 * <p> If this {@code Class} object represents an interface, the return
3966 * value is an array containing objects representing the uses of interface
3967 * types to specify interfaces directly extended by the interface. The
3968 * order of the objects in the array corresponds to the order of the
3969 * interface types used in the 'extends' clause of the declaration of this
3970 * {@code Class} object.
3971 *
3972 * <p> If this {@code Class} object represents a class or interface whose
3973 * declaration does not explicitly indicate any annotated superinterfaces,
3974 * the return value is an array of length 0.
3975 *
3976 * <p> If this {@code Class} object represents either the {@code Object}
3977 * class, an array type, a primitive type, or void, the return value is an
3978 * array of length 0.
3979 *
3980 * @return an array representing the superinterfaces
3981 * @since 1.8
3982 */
3983 public AnnotatedType[] getAnnotatedInterfaces() {
3984 return TypeAnnotationParser.buildAnnotatedInterfaces(getRawTypeAnnotations(), getConstantPool(), this);
3985 }
3986
3987 private native Class<?> getNestHost0();
3988
3989 /**
3990 * Returns the nest host of the <a href=#nest>nest</a> to which the class
3991 * or interface represented by this {@code Class} object belongs.
3992 * Every class and interface is a member of exactly one nest.
3993 * A class or interface that is not recorded as belonging to a nest
3994 * belongs to the nest consisting only of itself, and is the nest
3995 * host.
3996 *
3997 * <p>Each of the {@code Class} objects representing array types,
3998 * primitive types, and {@code void} returns {@code this} to indicate
3999 * that the represented entity belongs to the nest consisting only of
4000 * itself, and is the nest host.
4001 *
4002 * <p>If there is a {@linkplain LinkageError linkage error} accessing
4003 * the nest host, or if this class or interface is not enumerated as
4004 * a member of the nest by the nest host, then it is considered to belong
4005 * to its own nest and {@code this} is returned as the host.
4006 *
4007 * @apiNote A {@code class} file of version 55.0 or greater may record the
4008 * host of the nest to which it belongs by using the {@code NestHost}
4009 * attribute (JVMS 4.7.28). Alternatively, a {@code class} file of
4010 * version 55.0 or greater may act as a nest host by enumerating the nest's
4011 * other members with the
4012 * {@code NestMembers} attribute (JVMS 4.7.29).
4013 * A {@code class} file of version 54.0 or lower does not use these
4014 * attributes.
4015 *
4016 * @return the nest host of this class or interface
4017 *
4018 * @throws SecurityException
4019 * If the returned class is not the current class, and
4020 * if a security manager, <i>s</i>, is present and the caller's
4021 * class loader is not the same as or an ancestor of the class
4022 * loader for the returned class and invocation of {@link
4023 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
4024 * denies access to the package of the returned class
4025 * @since 11
4026 * @jvms 4.7.28 The {@code NestHost} Attribute
4027 * @jvms 4.7.29 The {@code NestMembers} Attribute
4028 * @jvms 5.4.4 Access Control
4029 */
4030 @CallerSensitive
4031 public Class<?> getNestHost() {
4032 if (isPrimitive() || isArray()) {
4033 return this;
4034 }
4035 Class<?> host;
4036 try {
4037 host = getNestHost0();
4038 } catch (LinkageError e) {
4039 // if we couldn't load our nest-host then we
4040 // act as-if we have no nest-host attribute
4041 return this;
4042 }
4043 // if null then nest membership validation failed, so we
4044 // act as-if we have no nest-host attribute
4045 if (host == null || host == this) {
4046 return this;
4047 }
4048 // returning a different class requires a security check
4049 SecurityManager sm = System.getSecurityManager();
4050 if (sm != null) {
4051 checkPackageAccess(sm,
4052 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
4053 }
4054 return host;
4055 }
4056
4057 /**
4058 * Determines if the given {@code Class} is a nestmate of the
4059 * class or interface represented by this {@code Class} object.
4060 * Two classes or interfaces are nestmates
4061 * if they have the same {@linkplain #getNestHost() nest host}.
4062 *
4063 * @param c the class to check
4064 * @return {@code true} if this class and {@code c} are members of
4065 * the same nest; and {@code false} otherwise.
4066 *
4067 * @since 11
4068 */
4069 public boolean isNestmateOf(Class<?> c) {
4070 if (this == c) {
4071 return true;
4072 }
4073 if (isPrimitive() || isArray() ||
4074 c.isPrimitive() || c.isArray()) {
4075 return false;
4076 }
4077 try {
4078 return getNestHost0() == c.getNestHost0();
4079 } catch (LinkageError e) {
4080 return false;
4081 }
4082 }
4083
4084 private native Class<?>[] getNestMembers0();
4085
4086 /**
4087 * Returns an array containing {@code Class} objects representing all the
4088 * classes and interfaces that are members of the nest to which the class
4089 * or interface represented by this {@code Class} object belongs.
4090 * The {@linkplain #getNestHost() nest host} of that nest is the zeroth
4091 * element of the array. Subsequent elements represent any classes or
4092 * interfaces that are recorded by the nest host as being members of
4093 * the nest; the order of such elements is unspecified. Duplicates are
4094 * permitted.
4095 * If the nest host of that nest does not enumerate any members, then the
4096 * array has a single element containing {@code this}.
4097 *
4098 * <p>Each of the {@code Class} objects representing array types,
4099 * primitive types, and {@code void} returns an array containing only
4100 * {@code this}.
4101 *
4102 * <p>This method validates that, for each class or interface which is
4103 * recorded as a member of the nest by the nest host, that class or
4104 * interface records itself as a member of that same nest. Any exceptions
4105 * that occur during this validation are rethrown by this method.
4106 *
4107 * @return an array of all classes and interfaces in the same nest as
4108 * this class
4109 *
4110 * @throws LinkageError
4111 * If there is any problem loading or validating a nest member or
4112 * its nest host
4113 * @throws SecurityException
4114 * If any returned class is not the current class, and
4115 * if a security manager, <i>s</i>, is present and the caller's
4116 * class loader is not the same as or an ancestor of the class
4117 * loader for that returned class and invocation of {@link
4118 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
4119 * denies access to the package of that returned class
4120 *
4121 * @since 11
4122 * @see #getNestHost()
4123 */
4124 @CallerSensitive
4125 public Class<?>[] getNestMembers() {
4126 if (isPrimitive() || isArray()) {
4127 return new Class<?>[] { this };
4128 }
4129 Class<?>[] members = getNestMembers0();
4130 // Can't actually enable this due to bootstrapping issues
4131 // assert(members.length != 1 || members[0] == this); // expected invariant from VM
4132
4133 if (members.length > 1) {
4134 // If we return anything other than the current class we need
4135 // a security check
4136 SecurityManager sm = System.getSecurityManager();
4137 if (sm != null) {
4138 checkPackageAccess(sm,
4139 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
4140 }
4141 }
4142 return members;
4143 }
4144
4145 /**
4146 * Returns the type descriptor string for this class.
4147 * <p>
4148 * Note that this is not a strict inverse of {@link #forName};
4149 * distinct classes which share a common name but have different class loaders
4150 * will have identical descriptor strings.
4151 *
4152 * @return the type descriptor representation
4153 * @jvms 4.3.2 Field Descriptors
4154 * @since 12
4155 */
4156 @Override
4157 public String descriptorString() {
4158 if (isPrimitive())
4159 return Wrapper.forPrimitiveType(this).basicTypeString();
4160 else if (isArray()) {
4161 return "[" + componentType.descriptorString();
4162 }
4163 else {
4164 return "L" + getName().replace('.', '/') + ";";
4165 }
4166 }
4167
4168 /**
4169 * Returns the component type of this {@code Class}, if it describes
4170 * an array type, or {@code null} otherwise.
4171 *
4172 * @implSpec
4173 * Equivalent to {@link Class#getComponentType()}.
4174 *
4175 * @return a {@code Class} describing the component type, or {@code null}
4176 * if this {@code Class} does not describe an array type
4177 * @since 12
4178 */
4179 @Override
4180 public Class<?> componentType() {
4181 return isArray() ? componentType : null;
4182 }
4183
4184 /**
4185 * Returns a {@code Class} for an array type whose component type
4186 * is described by this {@linkplain Class}.
4187 *
4188 * @return a {@code Class} describing the array type
4189 * @since 12
4190 */
4191 @Override
4192 public Class<?> arrayType() {
4193 return Array.newInstance(this, 0).getClass();
4194 }
4195
4196 /**
4197 * Returns a nominal descriptor for this instance, if one can be
4198 * constructed, or an empty {@link Optional} if one cannot be.
4199 *
4200 * @return An {@link Optional} containing the resulting nominal descriptor,
4201 * or an empty {@link Optional} if one cannot be constructed.
4202 * @since 12
4203 */
4204 @Override
4205 public Optional<ClassDesc> describeConstable() {
4206 return Optional.of(ClassDesc.ofDescriptor(descriptorString()));
4207 }
4208 }