1 /*
2 * Copyright (c) 1994, 2022, 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.invoke.MethodHandles;
32 import java.lang.module.ModuleReader;
33 import java.lang.ref.SoftReference;
34 import java.io.IOException;
35 import java.io.InputStream;
36 import java.io.ObjectStreamField;
37 import java.lang.reflect.AnnotatedElement;
38 import java.lang.reflect.AnnotatedType;
39 import java.lang.reflect.AccessFlag;
40 import java.lang.reflect.Array;
41 import java.lang.reflect.Constructor;
42 import java.lang.reflect.Executable;
43 import java.lang.reflect.Field;
44 import java.lang.reflect.GenericArrayType;
45 import java.lang.reflect.GenericDeclaration;
46 import java.lang.reflect.InvocationTargetException;
47 import java.lang.reflect.Member;
48 import java.lang.reflect.Method;
49 import java.lang.reflect.Modifier;
50 import java.lang.reflect.Proxy;
51 import java.lang.reflect.RecordComponent;
52 import java.lang.reflect.Type;
53 import java.lang.reflect.TypeVariable;
54 import java.lang.constant.Constable;
55 import java.net.URL;
56 import java.security.AccessController;
57 import java.security.PrivilegedAction;
58 import java.util.ArrayList;
59 import java.util.Arrays;
60 import java.util.Collection;
61 import java.util.HashMap;
62 import java.util.HashSet;
63 import java.util.LinkedHashMap;
64 import java.util.LinkedHashSet;
65 import java.util.List;
66 import java.util.Map;
67 import java.util.Objects;
68 import java.util.Optional;
69 import java.util.Set;
70 import java.util.stream.Collectors;
71
72 import jdk.internal.loader.BootLoader;
73 import jdk.internal.loader.BuiltinClassLoader;
74 import jdk.internal.misc.Unsafe;
75 import jdk.internal.module.Resources;
76 import jdk.internal.reflect.CallerSensitive;
77 import jdk.internal.reflect.CallerSensitiveAdapter;
78 import jdk.internal.reflect.ConstantPool;
79 import jdk.internal.reflect.Reflection;
80 import jdk.internal.reflect.ReflectionFactory;
81 import jdk.internal.vm.annotation.ForceInline;
82 import jdk.internal.vm.annotation.IntrinsicCandidate;
83 import sun.invoke.util.Wrapper;
84 import sun.reflect.generics.factory.CoreReflectionFactory;
85 import sun.reflect.generics.factory.GenericsFactory;
86 import sun.reflect.generics.repository.ClassRepository;
87 import sun.reflect.generics.repository.MethodRepository;
88 import sun.reflect.generics.repository.ConstructorRepository;
89 import sun.reflect.generics.scope.ClassScope;
90 import sun.security.util.SecurityConstants;
91 import sun.reflect.annotation.*;
92 import sun.reflect.misc.ReflectUtil;
93
94 /**
95 * Instances of the class {@code Class} represent classes and
96 * interfaces in a running Java application. An enum class and a record
97 * class are kinds of class; an annotation interface is a kind of
98 * interface. Every array also belongs to a class that is reflected as
99 * a {@code Class} object that is shared by all arrays with the same
100 * element type and number of dimensions. The primitive Java types
101 * ({@code boolean}, {@code byte}, {@code char}, {@code short}, {@code
102 * int}, {@code long}, {@code float}, and {@code double}), and the
103 * keyword {@code void} are also represented as {@code Class} objects.
104 *
105 * <p> {@code Class} has no public constructor. Instead a {@code Class}
106 * object is constructed automatically by the Java Virtual Machine when
107 * a class is derived from the bytes of a {@code class} file through
108 * the invocation of one of the following methods:
109 * <ul>
110 * <li> {@link ClassLoader#defineClass(String, byte[], int, int) ClassLoader::defineClass}
111 * <li> {@link java.lang.invoke.MethodHandles.Lookup#defineClass(byte[])
112 * java.lang.invoke.MethodHandles.Lookup::defineClass}
113 * <li> {@link java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
114 * java.lang.invoke.MethodHandles.Lookup::defineHiddenClass}
115 * </ul>
116 *
117 * <p> The methods of class {@code Class} expose many characteristics of a
118 * class or interface. Most characteristics are derived from the {@code class}
119 * file that the class loader passed to the Java Virtual Machine or
120 * from the {@code class} file passed to {@code Lookup::defineClass}
121 * or {@code Lookup::defineHiddenClass}.
122 * A few characteristics are determined by the class loading environment
123 * at run time, such as the module returned by {@link #getModule() getModule()}.
124 *
125 * <p> The following example uses a {@code Class} object to print the
126 * class name of an object:
127 *
128 * <blockquote><pre>
129 * void printClassName(Object obj) {
130 * System.out.println("The class of " + obj +
131 * " is " + obj.getClass().getName());
132 * }
133 * </pre></blockquote>
134 *
135 * It is also possible to get the {@code Class} object for a named
136 * class or interface (or for {@code void}) using a <i>class literal</i>.
137 * For example:
138 *
139 * <blockquote>
140 * {@code System.out.println("The name of class Foo is: "+Foo.class.getName());}
141 * </blockquote>
142 *
143 * <p> Some methods of class {@code Class} expose whether the declaration of
144 * a class or interface in Java source code was <em>enclosed</em> within
145 * another declaration. Other methods describe how a class or interface
146 * is situated in a <em>nest</em>. A <a id="nest">nest</a> is a set of
147 * classes and interfaces, in the same run-time package, that
148 * allow mutual access to their {@code private} members.
149 * The classes and interfaces are known as <em>nestmates</em>.
150 * One nestmate acts as the
151 * <em>nest host</em>, and enumerates the other nestmates which
152 * belong to the nest; each of them in turn records it as the nest host.
153 * The classes and interfaces which belong to a nest, including its host, are
154 * determined when
155 * {@code class} files are generated, for example, a Java compiler
156 * will typically record a top-level class as the host of a nest where the
157 * other members are the classes and interfaces whose declarations are
158 * enclosed within the top-level class declaration.
159 *
160 * <p> A class or interface created by the invocation of
161 * {@link java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
162 * Lookup::defineHiddenClass} is a {@linkplain Class#isHidden() <em>hidden</em>}
163 * class or interface.
164 * All kinds of class, including enum classes and record classes, may be
165 * hidden classes; all kinds of interface, including annotation interfaces,
166 * may be hidden interfaces.
167 *
168 * The {@linkplain #getName() name of a hidden class or interface} is
169 * not a <a href="ClassLoader.html#binary-name">binary name</a>,
170 * which means the following:
171 * <ul>
172 * <li>A hidden class or interface cannot be referenced by the constant pools
173 * of other classes and interfaces.
174 * <li>A hidden class or interface cannot be described in
175 * {@linkplain java.lang.constant.ConstantDesc <em>nominal form</em>} by
176 * {@link #describeConstable() Class::describeConstable},
177 * {@link ClassDesc#of(String) ClassDesc::of}, or
178 * {@link ClassDesc#ofDescriptor(String) ClassDesc::ofDescriptor}.
179 * <li>A hidden class or interface cannot be discovered by {@link #forName Class::forName}
180 * or {@link ClassLoader#loadClass(String, boolean) ClassLoader::loadClass}.
181 * </ul>
182 *
183 * A hidden class or interface is never an array class, but may be
184 * the element type of an array. In all other respects, the fact that
185 * a class or interface is hidden has no bearing on the characteristics
186 * exposed by the methods of class {@code Class}.
187 *
188 * @param <T> the type of the class modeled by this {@code Class}
189 * object. For example, the type of {@code String.class} is {@code
190 * Class<String>}. Use {@code Class<?>} if the class being modeled is
191 * unknown.
192 *
193 * @see java.lang.ClassLoader#defineClass(byte[], int, int)
194 * @since 1.0
195 * @jls 15.8.2 Class Literals
196 */
197 public final class Class<T> implements java.io.Serializable,
198 GenericDeclaration,
199 Type,
200 AnnotatedElement,
201 TypeDescriptor.OfField<Class<?>>,
202 Constable {
203 private static final int ANNOTATION= 0x00002000;
204 private static final int ENUM = 0x00004000;
205 private static final int SYNTHETIC = 0x00001000;
206
207 private static native void registerNatives();
208 static {
209 registerNatives();
210 }
211
212 /*
213 * Private constructor. Only the Java Virtual Machine creates Class objects.
214 * This constructor is not used and prevents the default constructor being
215 * generated.
216 */
217 private Class(ClassLoader loader, Class<?> arrayComponentType) {
218 // Initialize final field for classLoader. The initialization value of non-null
219 // prevents future JIT optimizations from assuming this final field is null.
220 classLoader = loader;
221 componentType = arrayComponentType;
222 }
223
224 /**
225 * Converts the object to a string. The string representation is the
226 * string "class" or "interface", followed by a space, and then by the
227 * name of the class in the format returned by {@code getName}.
228 * If this {@code Class} object represents a primitive type,
229 * this method returns the name of the primitive type. If
230 * this {@code Class} object represents void this method returns
231 * "void". If this {@code Class} object represents an array type,
232 * this method returns "class " followed by {@code getName}.
233 *
234 * @return a string representation of this {@code Class} object.
235 */
236 public String toString() {
237 String kind = isInterface() ? "interface " : isPrimitive() ? "" : "class ";
238 return kind.concat(getName());
239 }
240
241 /**
242 * Returns a string describing this {@code Class}, including
243 * information about modifiers and type parameters.
244 *
245 * The string is formatted as a list of type modifiers, if any,
246 * followed by the kind of type (empty string for primitive types
247 * and {@code class}, {@code enum}, {@code interface},
248 * {@code @interface}, or {@code record} as appropriate), followed
249 * by the type's name, followed by an angle-bracketed
250 * comma-separated list of the type's type parameters, if any,
251 * including informative bounds on the type parameters, if any.
252 *
253 * A space is used to separate modifiers from one another and to
254 * separate any modifiers from the kind of type. The modifiers
255 * occur in canonical order. If there are no type parameters, the
256 * type parameter list is elided.
257 *
258 * For an array type, the string starts with the type name,
259 * followed by an angle-bracketed comma-separated list of the
260 * type's type parameters, if any, followed by a sequence of
261 * {@code []} characters, one set of brackets per dimension of
262 * the array.
263 *
264 * <p>Note that since information about the runtime representation
265 * of a type is being generated, modifiers not present on the
266 * originating source code or illegal on the originating source
267 * code may be present.
268 *
269 * @return a string describing this {@code Class}, including
270 * information about modifiers and type parameters
271 *
272 * @since 1.8
273 */
274 public String toGenericString() {
275 if (isPrimitive()) {
276 return toString();
277 } else {
278 StringBuilder sb = new StringBuilder();
279 Class<?> component = this;
280 int arrayDepth = 0;
281
282 if (isArray()) {
283 do {
284 arrayDepth++;
285 component = component.getComponentType();
286 } while (component.isArray());
287 sb.append(component.getName());
288 } else {
289 // Class modifiers are a superset of interface modifiers
290 int modifiers = getModifiers() & Modifier.classModifiers();
291 if (modifiers != 0) {
292 sb.append(Modifier.toString(modifiers));
293 sb.append(' ');
294 }
295
296 if (isAnnotation()) {
297 sb.append('@');
298 }
299 if (isInterface()) { // Note: all annotation interfaces are interfaces
300 sb.append("interface");
301 } else {
302 if (isEnum())
303 sb.append("enum");
304 else if (isRecord())
305 sb.append("record");
306 else
307 sb.append("class");
308 }
309 sb.append(' ');
310 sb.append(getName());
311 }
312
313 TypeVariable<?>[] typeparms = component.getTypeParameters();
314 if (typeparms.length > 0) {
315 sb.append(Arrays.stream(typeparms)
316 .map(Class::typeVarBounds)
317 .collect(Collectors.joining(",", "<", ">")));
318 }
319
320 if (arrayDepth > 0) sb.append("[]".repeat(arrayDepth));
321
322 return sb.toString();
323 }
324 }
325
326 static String typeVarBounds(TypeVariable<?> typeVar) {
327 Type[] bounds = typeVar.getBounds();
328 if (bounds.length == 1 && bounds[0].equals(Object.class)) {
329 return typeVar.getName();
330 } else {
331 return typeVar.getName() + " extends " +
332 Arrays.stream(bounds)
333 .map(Type::getTypeName)
334 .collect(Collectors.joining(" & "));
335 }
336 }
337
338 /**
339 * Returns the {@code Class} object associated with the class or
340 * interface with the given string name. Invoking this method is
341 * equivalent to:
342 *
343 * <blockquote>
344 * {@code Class.forName(className, true, currentLoader)}
345 * </blockquote>
346 *
347 * where {@code currentLoader} denotes the defining class loader of
348 * the current class.
349 *
350 * <p> For example, the following code fragment returns the
351 * runtime {@code Class} descriptor for the class named
352 * {@code java.lang.Thread}:
353 *
354 * <blockquote>
355 * {@code Class t = Class.forName("java.lang.Thread")}
356 * </blockquote>
357 * <p>
358 * A call to {@code forName("X")} causes the class named
359 * {@code X} to be initialized.
360 *
361 * <p>
362 * In cases where this method is called from a context where there is no
363 * caller frame on the stack (e.g. when called directly from a JNI
364 * attached thread), the system class loader is used.
365 *
366 * @param className the fully qualified name of the desired class.
367 * @return the {@code Class} object for the class with the
368 * specified name.
369 * @throws LinkageError if the linkage fails
370 * @throws ExceptionInInitializerError if the initialization provoked
371 * by this method fails
372 * @throws ClassNotFoundException if the class cannot be located
373 *
374 * @jls 12.2 Loading of Classes and Interfaces
375 * @jls 12.3 Linking of Classes and Interfaces
376 * @jls 12.4 Initialization of Classes and Interfaces
377 */
378 @CallerSensitive
379 public static Class<?> forName(String className)
380 throws ClassNotFoundException {
381 Class<?> caller = Reflection.getCallerClass();
382 return forName(className, caller);
383 }
384
385 // Caller-sensitive adapter method for reflective invocation
386 @CallerSensitiveAdapter
387 private static Class<?> forName(String className, Class<?> caller)
388 throws ClassNotFoundException {
389 ClassLoader loader = (caller == null) ? ClassLoader.getSystemClassLoader()
390 : ClassLoader.getClassLoader(caller);
391 return forName0(className, true, loader, caller);
392 }
393
394 /**
395 * Returns the {@code Class} object associated with the class or
396 * interface with the given string name, using the given class loader.
397 * Given the fully qualified name for a class or interface (in the same
398 * format returned by {@code getName}) this method attempts to
399 * locate and load the class or interface. The specified class
400 * loader is used to load the class or interface. If the parameter
401 * {@code loader} is null, the class is loaded through the bootstrap
402 * class loader. The class is initialized only if the
403 * {@code initialize} parameter is {@code true} and if it has
404 * not been initialized earlier.
405 *
406 * <p> If {@code name} denotes a primitive type or void, an attempt
407 * will be made to locate a user-defined class in the unnamed package whose
408 * name is {@code name}. Therefore, this method cannot be used to
409 * obtain any of the {@code Class} objects representing primitive
410 * types or void.
411 *
412 * <p> If {@code name} denotes an array class, the component type of
413 * the array class is loaded but not initialized.
414 *
415 * <p> For example, in an instance method the expression:
416 *
417 * <blockquote>
418 * {@code Class.forName("Foo")}
419 * </blockquote>
420 *
421 * is equivalent to:
422 *
423 * <blockquote>
424 * {@code Class.forName("Foo", true, this.getClass().getClassLoader())}
425 * </blockquote>
426 *
427 * Note that this method throws errors related to loading, linking
428 * or initializing as specified in Sections {@jls 12.2}, {@jls
429 * 12.3}, and {@jls 12.4} of <cite>The Java Language
430 * Specification</cite>.
431 * Note that this method does not check whether the requested class
432 * is accessible to its caller.
433 *
434 * @param name fully qualified name of the desired class
435
436 * @param initialize if {@code true} the class will be initialized
437 * (which implies linking). See Section {@jls
438 * 12.4} of <cite>The Java Language
439 * Specification</cite>.
440 * @param loader class loader from which the class must be loaded
441 * @return class object representing the desired class
442 *
443 * @throws LinkageError if the linkage fails
444 * @throws ExceptionInInitializerError if the initialization provoked
445 * by this method fails
446 * @throws ClassNotFoundException if the class cannot be located by
447 * the specified class loader
448 * @throws SecurityException
449 * if a security manager is present, and the {@code loader} is
450 * {@code null}, and the caller's class loader is not
451 * {@code null}, and the caller does not have the
452 * {@link RuntimePermission}{@code ("getClassLoader")}
453 *
454 * @see java.lang.Class#forName(String)
455 * @see java.lang.ClassLoader
456 *
457 * @jls 12.2 Loading of Classes and Interfaces
458 * @jls 12.3 Linking of Classes and Interfaces
459 * @jls 12.4 Initialization of Classes and Interfaces
460 * @since 1.2
461 */
462 @CallerSensitive
463 public static Class<?> forName(String name, boolean initialize,
464 ClassLoader loader)
465 throws ClassNotFoundException
466 {
467 Class<?> caller = null;
468 @SuppressWarnings("removal")
469 SecurityManager sm = System.getSecurityManager();
470 if (sm != null) {
471 // Reflective call to get caller class is only needed if a security manager
472 // is present. Avoid the overhead of making this call otherwise.
473 caller = Reflection.getCallerClass();
474 }
475 return forName(name, initialize, loader, caller);
476 }
477
478 // Caller-sensitive adapter method for reflective invocation
479 @CallerSensitiveAdapter
480 private static Class<?> forName(String name, boolean initialize, ClassLoader loader, Class<?> caller)
481 throws ClassNotFoundException
482 {
483 @SuppressWarnings("removal")
484 SecurityManager sm = System.getSecurityManager();
485 if (sm != null) {
486 // Reflective call to get caller class is only needed if a security manager
487 // is present. Avoid the overhead of making this call otherwise.
488 if (loader == null) {
489 ClassLoader ccl = ClassLoader.getClassLoader(caller);
490 if (ccl != null) {
491 sm.checkPermission(
492 SecurityConstants.GET_CLASSLOADER_PERMISSION);
493 }
494 }
495 }
496 return forName0(name, initialize, loader, caller);
497 }
498
499 /** Called after security check for system loader access checks have been made. */
500 private static native Class<?> forName0(String name, boolean initialize,
501 ClassLoader loader,
502 Class<?> caller)
503 throws ClassNotFoundException;
504
505
506 /**
507 * Returns the {@code Class} with the given <a href="ClassLoader.html#binary-name">
508 * binary name</a> in the given module.
509 *
510 * <p> This method attempts to locate and load the class or interface.
511 * It does not link the class, and does not run the class initializer.
512 * If the class is not found, this method returns {@code null}. </p>
513 *
514 * <p> If the class loader of the given module defines other modules and
515 * the given name is a class defined in a different module, this method
516 * returns {@code null} after the class is loaded. </p>
517 *
518 * <p> This method does not check whether the requested class is
519 * accessible to its caller. </p>
520 *
521 * @apiNote
522 * This method returns {@code null} on failure rather than
523 * throwing a {@link ClassNotFoundException}, as is done by
524 * the {@link #forName(String, boolean, ClassLoader)} method.
525 * The security check is a stack-based permission check if the caller
526 * loads a class in another module.
527 *
528 * @param module A module
529 * @param name The <a href="ClassLoader.html#binary-name">binary name</a>
530 * of the class
531 * @return {@code Class} object of the given name defined in the given module;
532 * {@code null} if not found.
533 *
534 * @throws NullPointerException if the given module or name is {@code null}
535 *
536 * @throws LinkageError if the linkage fails
537 *
538 * @throws SecurityException
539 * <ul>
540 * <li> if the caller is not the specified module and
541 * {@code RuntimePermission("getClassLoader")} permission is denied; or</li>
542 * <li> access to the module content is denied. For example,
543 * permission check will be performed when a class loader calls
544 * {@link ModuleReader#open(String)} to read the bytes of a class file
545 * in a module.</li>
546 * </ul>
547 *
548 * @jls 12.2 Loading of Classes and Interfaces
549 * @jls 12.3 Linking of Classes and Interfaces
550 * @since 9
551 */
552 @SuppressWarnings("removal")
553 @CallerSensitive
554 public static Class<?> forName(Module module, String name) {
555 Class<?> caller = null;
556 SecurityManager sm = System.getSecurityManager();
557 if (sm != null) {
558 caller = Reflection.getCallerClass();
559 }
560 return forName(module, name, caller);
561 }
562
563 // Caller-sensitive adapter method for reflective invocation
564 @SuppressWarnings("removal")
565 @CallerSensitiveAdapter
566 private static Class<?> forName(Module module, String name, Class<?> caller) {
567 Objects.requireNonNull(module);
568 Objects.requireNonNull(name);
569
570 ClassLoader cl;
571 SecurityManager sm = System.getSecurityManager();
572 if (sm != null) {
573 if (caller != null && caller.getModule() != module) {
574 // if caller is null, Class.forName is the last java frame on the stack.
575 // java.base has all permissions
576 sm.checkPermission(SecurityConstants.GET_CLASSLOADER_PERMISSION);
577 }
578 PrivilegedAction<ClassLoader> pa = module::getClassLoader;
579 cl = AccessController.doPrivileged(pa);
580 } else {
581 cl = module.getClassLoader();
582 }
583
584 if (cl != null) {
585 return cl.loadClass(module, name);
586 } else {
587 return BootLoader.loadClass(module, name);
588 }
589 }
590
591 /**
592 * Creates a new instance of the class represented by this {@code Class}
593 * object. The class is instantiated as if by a {@code new}
594 * expression with an empty argument list. The class is initialized if it
595 * has not already been initialized.
596 *
597 * @deprecated This method propagates any exception thrown by the
598 * nullary constructor, including a checked exception. Use of
599 * this method effectively bypasses the compile-time exception
600 * checking that would otherwise be performed by the compiler.
601 * The {@link
602 * java.lang.reflect.Constructor#newInstance(java.lang.Object...)
603 * Constructor.newInstance} method avoids this problem by wrapping
604 * any exception thrown by the constructor in a (checked) {@link
605 * java.lang.reflect.InvocationTargetException}.
606 *
607 * <p>The call
608 *
609 * <pre>{@code
610 * clazz.newInstance()
611 * }</pre>
612 *
613 * can be replaced by
614 *
615 * <pre>{@code
616 * clazz.getDeclaredConstructor().newInstance()
617 * }</pre>
618 *
619 * The latter sequence of calls is inferred to be able to throw
620 * the additional exception types {@link
621 * InvocationTargetException} and {@link
622 * NoSuchMethodException}. Both of these exception types are
623 * subclasses of {@link ReflectiveOperationException}.
624 *
625 * @return a newly allocated instance of the class represented by this
626 * object.
627 * @throws IllegalAccessException if the class or its nullary
628 * constructor is not accessible.
629 * @throws InstantiationException
630 * if this {@code Class} represents an abstract class,
631 * an interface, an array class, a primitive type, or void;
632 * or if the class has no nullary constructor;
633 * or if the instantiation fails for some other reason.
634 * @throws ExceptionInInitializerError if the initialization
635 * provoked by this method fails.
636 * @throws SecurityException
637 * If a security manager, <i>s</i>, is present and
638 * the caller's class loader is not the same as or an
639 * ancestor of the class loader for the current class and
640 * invocation of {@link SecurityManager#checkPackageAccess
641 * s.checkPackageAccess()} denies access to the package
642 * of this class.
643 */
644 @SuppressWarnings("removal")
645 @CallerSensitive
646 @Deprecated(since="9")
647 public T newInstance()
648 throws InstantiationException, IllegalAccessException
649 {
650 SecurityManager sm = System.getSecurityManager();
651 if (sm != null) {
652 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), false);
653 }
654
655 // Constructor lookup
656 Constructor<T> tmpConstructor = cachedConstructor;
657 if (tmpConstructor == null) {
658 if (this == Class.class) {
659 throw new IllegalAccessException(
660 "Can not call newInstance() on the Class for java.lang.Class"
661 );
662 }
663 try {
664 Class<?>[] empty = {};
665 final Constructor<T> c = getReflectionFactory().copyConstructor(
666 getConstructor0(empty, Member.DECLARED));
667 // Disable accessibility checks on the constructor
668 // access check is done with the true caller
669 java.security.AccessController.doPrivileged(
670 new java.security.PrivilegedAction<>() {
671 public Void run() {
672 c.setAccessible(true);
673 return null;
674 }
675 });
676 cachedConstructor = tmpConstructor = c;
677 } catch (NoSuchMethodException e) {
678 throw (InstantiationException)
679 new InstantiationException(getName()).initCause(e);
680 }
681 }
682
683 try {
684 Class<?> caller = Reflection.getCallerClass();
685 return getReflectionFactory().newInstance(tmpConstructor, null, caller);
686 } catch (InvocationTargetException e) {
687 Unsafe.getUnsafe().throwException(e.getTargetException());
688 // Not reached
689 return null;
690 }
691 }
692
693 private transient volatile Constructor<T> cachedConstructor;
694
695 /**
696 * Determines if the specified {@code Object} is assignment-compatible
697 * with the object represented by this {@code Class}. This method is
698 * the dynamic equivalent of the Java language {@code instanceof}
699 * operator. The method returns {@code true} if the specified
700 * {@code Object} argument is non-null and can be cast to the
701 * reference type represented by this {@code Class} object without
702 * raising a {@code ClassCastException.} It returns {@code false}
703 * otherwise.
704 *
705 * <p> Specifically, if this {@code Class} object represents a
706 * declared class, this method returns {@code true} if the specified
707 * {@code Object} argument is an instance of the represented class (or
708 * of any of its subclasses); it returns {@code false} otherwise. If
709 * this {@code Class} object represents an array class, this method
710 * returns {@code true} if the specified {@code Object} argument
711 * can be converted to an object of the array class by an identity
712 * conversion or by a widening reference conversion; it returns
713 * {@code false} otherwise. If this {@code Class} object
714 * represents an interface, this method returns {@code true} if the
715 * class or any superclass of the specified {@code Object} argument
716 * implements this interface; it returns {@code false} otherwise. If
717 * this {@code Class} object represents a primitive type, this method
718 * returns {@code false}.
719 *
720 * @param obj the object to check
721 * @return true if {@code obj} is an instance of this class
722 *
723 * @since 1.1
724 */
725 @IntrinsicCandidate
726 public native boolean isInstance(Object obj);
727
728
729 /**
730 * Determines if the class or interface represented by this
731 * {@code Class} object is either the same as, or is a superclass or
732 * superinterface of, the class or interface represented by the specified
733 * {@code Class} parameter. It returns {@code true} if so;
734 * otherwise it returns {@code false}. If this {@code Class}
735 * object represents a primitive type, this method returns
736 * {@code true} if the specified {@code Class} parameter is
737 * exactly this {@code Class} object; otherwise it returns
738 * {@code false}.
739 *
740 * <p> Specifically, this method tests whether the type represented by the
741 * specified {@code Class} parameter can be converted to the type
742 * represented by this {@code Class} object via an identity conversion
743 * or via a widening reference conversion. See <cite>The Java Language
744 * Specification</cite>, sections {@jls 5.1.1} and {@jls 5.1.4},
745 * for details.
746 *
747 * @param cls the {@code Class} object to be checked
748 * @return the {@code boolean} value indicating whether objects of the
749 * type {@code cls} can be assigned to objects of this class
750 * @throws NullPointerException if the specified Class parameter is
751 * null.
752 * @since 1.1
753 */
754 @IntrinsicCandidate
755 public native boolean isAssignableFrom(Class<?> cls);
756
757
758 /**
759 * Determines if this {@code Class} object represents an
760 * interface type.
761 *
762 * @return {@code true} if this {@code Class} object represents an interface;
763 * {@code false} otherwise.
764 */
765 @IntrinsicCandidate
766 public native boolean isInterface();
767
768
769 /**
770 * Determines if this {@code Class} object represents an array class.
771 *
772 * @return {@code true} if this {@code Class} object represents an array class;
773 * {@code false} otherwise.
774 * @since 1.1
775 */
776 @IntrinsicCandidate
777 public native boolean isArray();
778
779
780 /**
781 * Determines if the specified {@code Class} object represents a
782 * primitive type.
783 *
784 * <p> There are nine predefined {@code Class} objects to represent
785 * the eight primitive types and void. These are created by the Java
786 * Virtual Machine, and have the same names as the primitive types that
787 * they represent, namely {@code boolean}, {@code byte},
788 * {@code char}, {@code short}, {@code int},
789 * {@code long}, {@code float}, and {@code double}.
790 *
791 * <p> These objects may only be accessed via the following public static
792 * final variables, and are the only {@code Class} objects for which
793 * this method returns {@code true}.
794 *
795 * @return true if and only if this class represents a primitive type
796 *
797 * @see java.lang.Boolean#TYPE
798 * @see java.lang.Character#TYPE
799 * @see java.lang.Byte#TYPE
800 * @see java.lang.Short#TYPE
801 * @see java.lang.Integer#TYPE
802 * @see java.lang.Long#TYPE
803 * @see java.lang.Float#TYPE
804 * @see java.lang.Double#TYPE
805 * @see java.lang.Void#TYPE
806 * @since 1.1
807 */
808 @IntrinsicCandidate
809 public native boolean isPrimitive();
810
811 /**
812 * Returns true if this {@code Class} object represents an annotation
813 * interface. Note that if this method returns true, {@link #isInterface()}
814 * would also return true, as all annotation interfaces are also interfaces.
815 *
816 * @return {@code true} if this {@code Class} object represents an annotation
817 * interface; {@code false} otherwise
818 * @since 1.5
819 */
820 public boolean isAnnotation() {
821 return (getModifiers() & ANNOTATION) != 0;
822 }
823
824 /**
825 *{@return {@code true} if and only if this class has the synthetic modifier
826 * bit set}
827 *
828 * @jls 13.1 The Form of a Binary
829 * @jvms 4.1 The {@code ClassFile} Structure
830 * @see <a
831 * href="{@docRoot}/java.base/java/lang/reflect/package-summary.html#LanguageJvmModel">Java
832 * programming language and JVM modeling in core reflection</a>
833 * @since 1.5
834 */
835 public boolean isSynthetic() {
836 return (getModifiers() & SYNTHETIC) != 0;
837 }
838
839 /**
840 * Returns the name of the entity (class, interface, array class,
841 * primitive type, or void) represented by this {@code Class} object.
842 *
843 * <p> If this {@code Class} object represents a class or interface,
844 * not an array class, then:
845 * <ul>
846 * <li> If the class or interface is not {@linkplain #isHidden() hidden},
847 * then the <a href="ClassLoader.html#binary-name">binary name</a>
848 * of the class or interface is returned.
849 * <li> If the class or interface is hidden, then the result is a string
850 * of the form: {@code N + '/' + <suffix>}
851 * where {@code N} is the <a href="ClassLoader.html#binary-name">binary name</a>
852 * indicated by the {@code class} file passed to
853 * {@link java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
854 * Lookup::defineHiddenClass}, and {@code <suffix>} is an unqualified name.
855 * </ul>
856 *
857 * <p> If this {@code Class} object represents an array class, then
858 * the result is a string consisting of one or more '{@code [}' characters
859 * representing the depth of the array nesting, followed by the element
860 * type as encoded using the following table:
861 *
862 * <blockquote><table class="striped">
863 * <caption style="display:none">Element types and encodings</caption>
864 * <thead>
865 * <tr><th scope="col"> Element Type <th scope="col"> Encoding
866 * </thead>
867 * <tbody style="text-align:left">
868 * <tr><th scope="row"> {@code boolean} <td style="text-align:center"> {@code Z}
869 * <tr><th scope="row"> {@code byte} <td style="text-align:center"> {@code B}
870 * <tr><th scope="row"> {@code char} <td style="text-align:center"> {@code C}
871 * <tr><th scope="row"> class or interface with <a href="ClassLoader.html#binary-name">binary name</a> <i>N</i>
872 * <td style="text-align:center"> {@code L}<em>N</em>{@code ;}
873 * <tr><th scope="row"> {@code double} <td style="text-align:center"> {@code D}
874 * <tr><th scope="row"> {@code float} <td style="text-align:center"> {@code F}
875 * <tr><th scope="row"> {@code int} <td style="text-align:center"> {@code I}
876 * <tr><th scope="row"> {@code long} <td style="text-align:center"> {@code J}
877 * <tr><th scope="row"> {@code short} <td style="text-align:center"> {@code S}
878 * </tbody>
879 * </table></blockquote>
880 *
881 * <p> If this {@code Class} object represents a primitive type or {@code void},
882 * then the result is a string with the same spelling as the Java language
883 * keyword which corresponds to the primitive type or {@code void}.
884 *
885 * <p> Examples:
886 * <blockquote><pre>
887 * String.class.getName()
888 * returns "java.lang.String"
889 * byte.class.getName()
890 * returns "byte"
891 * (new Object[3]).getClass().getName()
892 * returns "[Ljava.lang.Object;"
893 * (new int[3][4][5][6][7][8][9]).getClass().getName()
894 * returns "[[[[[[[I"
895 * </pre></blockquote>
896 *
897 * @return the name of the class, interface, or other entity
898 * represented by this {@code Class} object.
899 * @jls 13.1 The Form of a Binary
900 */
901 public String getName() {
902 String name = this.name;
903 return name != null ? name : initClassName();
904 }
905
906 // Cache the name to reduce the number of calls into the VM.
907 // This field would be set by VM itself during initClassName call.
908 private transient String name;
909 private native String initClassName();
910
911 /**
912 * Returns the class loader for the class. Some implementations may use
913 * null to represent the bootstrap class loader. This method will return
914 * null in such implementations if this class was loaded by the bootstrap
915 * class loader.
916 *
917 * <p>If this {@code Class} object
918 * represents a primitive type or void, null is returned.
919 *
920 * @return the class loader that loaded the class or interface
921 * represented by this {@code Class} object.
922 * @throws SecurityException
923 * if a security manager is present, and the caller's class loader
924 * is not {@code null} and is not the same as or an ancestor of the
925 * class loader for the class whose class loader is requested,
926 * and the caller does not have the
927 * {@link RuntimePermission}{@code ("getClassLoader")}
928 * @see java.lang.ClassLoader
929 * @see SecurityManager#checkPermission
930 * @see java.lang.RuntimePermission
931 */
932 @CallerSensitive
933 @ForceInline // to ensure Reflection.getCallerClass optimization
934 public ClassLoader getClassLoader() {
935 ClassLoader cl = classLoader;
936 if (cl == null)
937 return null;
938 @SuppressWarnings("removal")
939 SecurityManager sm = System.getSecurityManager();
940 if (sm != null) {
941 ClassLoader.checkClassLoaderPermission(cl, Reflection.getCallerClass());
942 }
943 return cl;
944 }
945
946 // Package-private to allow ClassLoader access
947 ClassLoader getClassLoader0() { return classLoader; }
948
949 /**
950 * Returns the module that this class or interface is a member of.
951 *
952 * If this class represents an array type then this method returns the
953 * {@code Module} for the element type. If this class represents a
954 * primitive type or void, then the {@code Module} object for the
955 * {@code java.base} module is returned.
956 *
957 * If this class is in an unnamed module then the {@linkplain
958 * ClassLoader#getUnnamedModule() unnamed} {@code Module} of the class
959 * loader for this class is returned.
960 *
961 * @return the module that this class or interface is a member of
962 *
963 * @since 9
964 */
965 public Module getModule() {
966 return module;
967 }
968
969 // set by VM
970 private transient Module module;
971
972 // Initialized in JVM not by private constructor
973 // This field is filtered from reflection access, i.e. getDeclaredField
974 // will throw NoSuchFieldException
975 private final ClassLoader classLoader;
976
977 // Set by VM
978 private transient Object classData;
979
980 // package-private
981 Object getClassData() {
982 return classData;
983 }
984
985 /**
986 * Returns an array of {@code TypeVariable} objects that represent the
987 * type variables declared by the generic declaration represented by this
988 * {@code GenericDeclaration} object, in declaration order. Returns an
989 * array of length 0 if the underlying generic declaration declares no type
990 * variables.
991 *
992 * @return an array of {@code TypeVariable} objects that represent
993 * the type variables declared by this generic declaration
994 * @throws java.lang.reflect.GenericSignatureFormatError if the generic
995 * signature of this generic declaration does not conform to
996 * the format specified in section {@jvms 4.7.9} of
997 * <cite>The Java Virtual Machine Specification</cite>
998 * @since 1.5
999 */
1000 @SuppressWarnings("unchecked")
1001 public TypeVariable<Class<T>>[] getTypeParameters() {
1002 ClassRepository info = getGenericInfo();
1003 if (info != null)
1004 return (TypeVariable<Class<T>>[])info.getTypeParameters();
1005 else
1006 return (TypeVariable<Class<T>>[])new TypeVariable<?>[0];
1007 }
1008
1009
1010 /**
1011 * Returns the {@code Class} representing the direct superclass of the
1012 * entity (class, interface, primitive type or void) represented by
1013 * this {@code Class}. If this {@code Class} represents either the
1014 * {@code Object} class, an interface, a primitive type, or void, then
1015 * null is returned. If this {@code Class} object represents an array class
1016 * then the {@code Class} object representing the {@code Object} class is
1017 * returned.
1018 *
1019 * @return the direct superclass of the class represented by this {@code Class} object
1020 */
1021 @IntrinsicCandidate
1022 public native Class<? super T> getSuperclass();
1023
1024
1025 /**
1026 * Returns the {@code Type} representing the direct superclass of
1027 * the entity (class, interface, primitive type or void) represented by
1028 * this {@code Class} object.
1029 *
1030 * <p>If the superclass is a parameterized type, the {@code Type}
1031 * object returned must accurately reflect the actual type
1032 * arguments used in the source code. The parameterized type
1033 * representing the superclass is created if it had not been
1034 * created before. See the declaration of {@link
1035 * java.lang.reflect.ParameterizedType ParameterizedType} for the
1036 * semantics of the creation process for parameterized types. If
1037 * this {@code Class} object represents either the {@code Object}
1038 * class, an interface, a primitive type, or void, then null is
1039 * returned. If this {@code Class} object represents an array class
1040 * then the {@code Class} object representing the {@code Object} class is
1041 * returned.
1042 *
1043 * @throws java.lang.reflect.GenericSignatureFormatError if the generic
1044 * class signature does not conform to the format specified in
1045 * section {@jvms 4.7.9} of <cite>The Java Virtual
1046 * Machine Specification</cite>
1047 * @throws TypeNotPresentException if the generic superclass
1048 * refers to a non-existent type declaration
1049 * @throws java.lang.reflect.MalformedParameterizedTypeException if the
1050 * generic superclass refers to a parameterized type that cannot be
1051 * instantiated for any reason
1052 * @return the direct superclass of the class represented by this {@code Class} object
1053 * @since 1.5
1054 */
1055 public Type getGenericSuperclass() {
1056 ClassRepository info = getGenericInfo();
1057 if (info == null) {
1058 return getSuperclass();
1059 }
1060
1061 // Historical irregularity:
1062 // Generic signature marks interfaces with superclass = Object
1063 // but this API returns null for interfaces
1064 if (isInterface()) {
1065 return null;
1066 }
1067
1068 return info.getSuperclass();
1069 }
1070
1071 /**
1072 * Gets the package of this class.
1073 *
1074 * <p>If this class represents an array type, a primitive type or void,
1075 * this method returns {@code null}.
1076 *
1077 * @return the package of this class.
1078 * @revised 9
1079 */
1080 public Package getPackage() {
1081 if (isPrimitive() || isArray()) {
1082 return null;
1083 }
1084 ClassLoader cl = classLoader;
1085 return cl != null ? cl.definePackage(this)
1086 : BootLoader.definePackage(this);
1087 }
1088
1089 /**
1090 * Returns the fully qualified package name.
1091 *
1092 * <p> If this class is a top level class, then this method returns the fully
1093 * qualified name of the package that the class is a member of, or the
1094 * empty string if the class is in an unnamed package.
1095 *
1096 * <p> If this class is a member class, then this method is equivalent to
1097 * invoking {@code getPackageName()} on the {@linkplain #getEnclosingClass
1098 * enclosing class}.
1099 *
1100 * <p> If this class is a {@linkplain #isLocalClass local class} or an {@linkplain
1101 * #isAnonymousClass() anonymous class}, then this method is equivalent to
1102 * invoking {@code getPackageName()} on the {@linkplain #getDeclaringClass
1103 * declaring class} of the {@linkplain #getEnclosingMethod enclosing method} or
1104 * {@linkplain #getEnclosingConstructor enclosing constructor}.
1105 *
1106 * <p> If this class represents an array type then this method returns the
1107 * package name of the element type. If this class represents a primitive
1108 * type or void then the package name "{@code java.lang}" is returned.
1109 *
1110 * @return the fully qualified package name
1111 *
1112 * @since 9
1113 * @jls 6.7 Fully Qualified Names
1114 */
1115 public String getPackageName() {
1116 String pn = this.packageName;
1117 if (pn == null) {
1118 Class<?> c = isArray() ? elementType() : this;
1119 if (c.isPrimitive()) {
1120 pn = "java.lang";
1121 } else {
1122 String cn = c.getName();
1123 int dot = cn.lastIndexOf('.');
1124 pn = (dot != -1) ? cn.substring(0, dot).intern() : "";
1125 }
1126 this.packageName = pn;
1127 }
1128 return pn;
1129 }
1130
1131 // cached package name
1132 private transient String packageName;
1133
1134 /**
1135 * Returns the interfaces directly implemented by the class or interface
1136 * represented by this {@code Class} object.
1137 *
1138 * <p>If this {@code Class} object represents a class, the return value is an array
1139 * containing objects representing all interfaces directly implemented by
1140 * the class. The order of the interface objects in the array corresponds
1141 * to the order of the interface names in the {@code implements} clause of
1142 * the declaration of the class represented by this {@code Class} object. For example,
1143 * given the declaration:
1144 * <blockquote>
1145 * {@code class Shimmer implements FloorWax, DessertTopping { ... }}
1146 * </blockquote>
1147 * suppose the value of {@code s} is an instance of
1148 * {@code Shimmer}; the value of the expression:
1149 * <blockquote>
1150 * {@code s.getClass().getInterfaces()[0]}
1151 * </blockquote>
1152 * is the {@code Class} object that represents interface
1153 * {@code FloorWax}; and the value of:
1154 * <blockquote>
1155 * {@code s.getClass().getInterfaces()[1]}
1156 * </blockquote>
1157 * is the {@code Class} object that represents interface
1158 * {@code DessertTopping}.
1159 *
1160 * <p>If this {@code Class} object represents an interface, the array contains objects
1161 * representing all interfaces directly extended by the interface. The
1162 * order of the interface objects in the array corresponds to the order of
1163 * the interface names in the {@code extends} clause of the declaration of
1164 * the interface represented by this {@code Class} object.
1165 *
1166 * <p>If this {@code Class} object represents a class or interface that implements no
1167 * interfaces, the method returns an array of length 0.
1168 *
1169 * <p>If this {@code Class} object represents a primitive type or void, the method
1170 * returns an array of length 0.
1171 *
1172 * <p>If this {@code Class} object represents an array type, the
1173 * interfaces {@code Cloneable} and {@code java.io.Serializable} are
1174 * returned in that order.
1175 *
1176 * @return an array of interfaces directly implemented by this class
1177 */
1178 public Class<?>[] getInterfaces() {
1179 // defensively copy before handing over to user code
1180 return getInterfaces(true);
1181 }
1182
1183 private Class<?>[] getInterfaces(boolean cloneArray) {
1184 ReflectionData<T> rd = reflectionData();
1185 if (rd == null) {
1186 // no cloning required
1187 return getInterfaces0();
1188 } else {
1189 Class<?>[] interfaces = rd.interfaces;
1190 if (interfaces == null) {
1191 interfaces = getInterfaces0();
1192 rd.interfaces = interfaces;
1193 }
1194 // defensively copy if requested
1195 return cloneArray ? interfaces.clone() : interfaces;
1196 }
1197 }
1198
1199 private native Class<?>[] getInterfaces0();
1200
1201 /**
1202 * Returns the {@code Type}s representing the interfaces
1203 * directly implemented by the class or interface represented by
1204 * this {@code Class} object.
1205 *
1206 * <p>If a superinterface is a parameterized type, the
1207 * {@code Type} object returned for it must accurately reflect
1208 * the actual type arguments used in the source code. The
1209 * parameterized type representing each superinterface is created
1210 * if it had not been created before. See the declaration of
1211 * {@link java.lang.reflect.ParameterizedType ParameterizedType}
1212 * for the semantics of the creation process for parameterized
1213 * types.
1214 *
1215 * <p>If this {@code Class} object represents a class, the return value is an array
1216 * containing objects representing all interfaces directly implemented by
1217 * the class. The order of the interface objects in the array corresponds
1218 * to the order of the interface names in the {@code implements} clause of
1219 * the declaration of the class represented by this {@code Class} object.
1220 *
1221 * <p>If this {@code Class} object represents an interface, the array contains objects
1222 * representing all interfaces directly extended by the interface. The
1223 * order of the interface objects in the array corresponds to the order of
1224 * the interface names in the {@code extends} clause of the declaration of
1225 * the interface represented by this {@code Class} object.
1226 *
1227 * <p>If this {@code Class} object represents a class or interface that implements no
1228 * interfaces, the method returns an array of length 0.
1229 *
1230 * <p>If this {@code Class} object represents a primitive type or void, the method
1231 * returns an array of length 0.
1232 *
1233 * <p>If this {@code Class} object represents an array type, the
1234 * interfaces {@code Cloneable} and {@code java.io.Serializable} are
1235 * returned in that order.
1236 *
1237 * @throws java.lang.reflect.GenericSignatureFormatError
1238 * if the generic class signature does not conform to the
1239 * format specified in section {@jvms 4.7.9} of <cite>The
1240 * Java Virtual Machine Specification</cite>
1241 * @throws TypeNotPresentException if any of the generic
1242 * superinterfaces refers to a non-existent type declaration
1243 * @throws java.lang.reflect.MalformedParameterizedTypeException
1244 * if any of the generic superinterfaces refer to a parameterized
1245 * type that cannot be instantiated for any reason
1246 * @return an array of interfaces directly implemented by this class
1247 * @since 1.5
1248 */
1249 public Type[] getGenericInterfaces() {
1250 ClassRepository info = getGenericInfo();
1251 return (info == null) ? getInterfaces() : info.getSuperInterfaces();
1252 }
1253
1254
1255 /**
1256 * Returns the {@code Class} representing the component type of an
1257 * array. If this class does not represent an array class this method
1258 * returns null.
1259 *
1260 * @return the {@code Class} representing the component type of this
1261 * class if this class is an array
1262 * @see java.lang.reflect.Array
1263 * @since 1.1
1264 */
1265 public Class<?> getComponentType() {
1266 // Only return for array types. Storage may be reused for Class for instance types.
1267 if (isArray()) {
1268 return componentType;
1269 } else {
1270 return null;
1271 }
1272 }
1273
1274 private final Class<?> componentType;
1275
1276 /*
1277 * Returns the {@code Class} representing the element type of an array class.
1278 * If this class does not represent an array class, then this method returns
1279 * {@code null}.
1280 */
1281 private Class<?> elementType() {
1282 if (!isArray()) return null;
1283
1284 Class<?> c = this;
1285 while (c.isArray()) {
1286 c = c.getComponentType();
1287 }
1288 return c;
1289 }
1290
1291 /**
1292 * Returns the Java language modifiers for this class or interface, encoded
1293 * in an integer. The modifiers consist of the Java Virtual Machine's
1294 * constants for {@code public}, {@code protected},
1295 * {@code private}, {@code final}, {@code static},
1296 * {@code abstract} and {@code interface}; they should be decoded
1297 * using the methods of class {@code Modifier}.
1298 *
1299 * <p> If the underlying class is an array class:
1300 * <ul>
1301 * <li> its {@code public}, {@code private} and {@code protected}
1302 * modifiers are the same as those of its component type
1303 * <li> its {@code abstract} and {@code final} modifiers are always
1304 * {@code true}
1305 * <li> its interface modifier is always {@code false}, even when
1306 * the component type is an interface
1307 * </ul>
1308 * If this {@code Class} object represents a primitive type or
1309 * void, its {@code public}, {@code abstract}, and {@code final}
1310 * modifiers are always {@code true}.
1311 * For {@code Class} objects representing void, primitive types, and
1312 * arrays, the values of other modifiers are {@code false} other
1313 * than as specified above.
1314 *
1315 * <p> The modifier encodings are defined in section {@jvms 4.1}
1316 * of <cite>The Java Virtual Machine Specification</cite>.
1317 *
1318 * @return the {@code int} representing the modifiers for this class
1319 * @see java.lang.reflect.Modifier
1320 * @see #accessFlags()
1321 * @see <a
1322 * href="{@docRoot}/java.base/java/lang/reflect/package-summary.html#LanguageJvmModel">Java
1323 * programming language and JVM modeling in core reflection</a>
1324 * @since 1.1
1325 * @jls 8.1.1 Class Modifiers
1326 * @jls 9.1.1. Interface Modifiers
1327 * @jvms 4.1 The {@code ClassFile} Structure
1328 */
1329 @IntrinsicCandidate
1330 public native int getModifiers();
1331
1332 /**
1333 * {@return an unmodifiable set of the {@linkplain AccessFlag access
1334 * flags} for this class, possibly empty}
1335 *
1336 * <p> If the underlying class is an array class:
1337 * <ul>
1338 * <li> its {@code PUBLIC}, {@code PRIVATE} and {@code PROTECTED}
1339 * access flags are the same as those of its component type
1340 * <li> its {@code ABSTRACT} and {@code FINAL} flags are present
1341 * <li> its {@code INTERFACE} flag is absent, even when the
1342 * component type is an interface
1343 * </ul>
1344 * If this {@code Class} object represents a primitive type or
1345 * void, the flags are {@code PUBLIC}, {@code ABSTRACT}, and
1346 * {@code FINAL}.
1347 * For {@code Class} objects representing void, primitive types, and
1348 * arrays, access flags are absent other than as specified above.
1349 *
1350 * @see #getModifiers()
1351 * @jvms 4.1 The ClassFile Structure
1352 * @jvms 4.7.6 The InnerClasses Attribute
1353 * @since 20
1354 */
1355 public Set<AccessFlag> accessFlags() {
1356 // Location.CLASS allows SUPER and AccessFlag.MODULE which
1357 // INNER_CLASS forbids. INNER_CLASS allows PRIVATE, PROTECTED,
1358 // and STATIC, which are not allowed on Location.CLASS.
1359 // Use getClassAccessFlagsRaw to expose SUPER status.
1360 var location = (isMemberClass() || isLocalClass() ||
1361 isAnonymousClass() || isArray()) ?
1362 AccessFlag.Location.INNER_CLASS :
1363 AccessFlag.Location.CLASS;
1364 return AccessFlag.maskToAccessFlags((location == AccessFlag.Location.CLASS) ?
1365 getClassAccessFlagsRaw() :
1366 getModifiers(),
1367 location);
1368 }
1369
1370 /**
1371 * Gets the signers of this class.
1372 *
1373 * @return the signers of this class, or null if there are no signers. In
1374 * particular, this method returns null if this {@code Class} object represents
1375 * a primitive type or void.
1376 * @since 1.1
1377 */
1378 public native Object[] getSigners();
1379
1380
1381 /**
1382 * Set the signers of this class.
1383 */
1384 native void setSigners(Object[] signers);
1385
1386
1387 /**
1388 * If this {@code Class} object represents a local or anonymous
1389 * class within a method, returns a {@link
1390 * java.lang.reflect.Method Method} object representing the
1391 * immediately enclosing method of the underlying class. Returns
1392 * {@code null} otherwise.
1393 *
1394 * In particular, this method returns {@code null} if the underlying
1395 * class is a local or anonymous class immediately enclosed by a class or
1396 * interface declaration, instance initializer or static initializer.
1397 *
1398 * @return the immediately enclosing method of the underlying class, if
1399 * that class is a local or anonymous class; otherwise {@code null}.
1400 *
1401 * @throws SecurityException
1402 * If a security manager, <i>s</i>, is present and any of the
1403 * following conditions is met:
1404 *
1405 * <ul>
1406 *
1407 * <li> the caller's class loader is not the same as the
1408 * class loader of the enclosing class and invocation of
1409 * {@link SecurityManager#checkPermission
1410 * s.checkPermission} method with
1411 * {@code RuntimePermission("accessDeclaredMembers")}
1412 * denies access to the methods within the enclosing class
1413 *
1414 * <li> the caller's class loader is not the same as or an
1415 * ancestor of the class loader for the enclosing class and
1416 * invocation of {@link SecurityManager#checkPackageAccess
1417 * s.checkPackageAccess()} denies access to the package
1418 * of the enclosing class
1419 *
1420 * </ul>
1421 * @since 1.5
1422 */
1423 @CallerSensitive
1424 public Method getEnclosingMethod() throws SecurityException {
1425 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1426
1427 if (enclosingInfo == null)
1428 return null;
1429 else {
1430 if (!enclosingInfo.isMethod())
1431 return null;
1432
1433 MethodRepository typeInfo = MethodRepository.make(enclosingInfo.getDescriptor(),
1434 getFactory());
1435 Class<?> returnType = toClass(typeInfo.getReturnType());
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 @SuppressWarnings("removal")
1448 SecurityManager sm = System.getSecurityManager();
1449 if (sm != null) {
1450 enclosingCandidate.checkMemberAccess(sm, Member.DECLARED,
1451 Reflection.getCallerClass(), true);
1452 }
1453 Method[] candidates = enclosingCandidate.privateGetDeclaredMethods(false);
1454
1455 /*
1456 * Loop over all declared methods; match method name,
1457 * number of and type of parameters, *and* return
1458 * type. Matching return type is also necessary
1459 * because of covariant returns, etc.
1460 */
1461 ReflectionFactory fact = getReflectionFactory();
1462 for (Method m : candidates) {
1463 if (m.getName().equals(enclosingInfo.getName()) &&
1464 arrayContentsEq(parameterClasses,
1465 fact.getExecutableSharedParameterTypes(m))) {
1466 // finally, check return type
1467 if (m.getReturnType().equals(returnType)) {
1468 return fact.copyMethod(m);
1469 }
1470 }
1471 }
1472
1473 throw new InternalError("Enclosing method not found");
1474 }
1475 }
1476
1477 private native Object[] getEnclosingMethod0();
1478
1479 private EnclosingMethodInfo getEnclosingMethodInfo() {
1480 Object[] enclosingInfo = getEnclosingMethod0();
1481 if (enclosingInfo == null)
1482 return null;
1483 else {
1484 return new EnclosingMethodInfo(enclosingInfo);
1485 }
1486 }
1487
1488 private static final class EnclosingMethodInfo {
1489 private final Class<?> enclosingClass;
1490 private final String name;
1491 private final String descriptor;
1492
1493 static void validate(Object[] enclosingInfo) {
1494 if (enclosingInfo.length != 3)
1495 throw new InternalError("Malformed enclosing method information");
1496 try {
1497 // The array is expected to have three elements:
1498
1499 // the immediately enclosing class
1500 Class<?> enclosingClass = (Class<?>)enclosingInfo[0];
1501 assert(enclosingClass != null);
1502
1503 // the immediately enclosing method or constructor's
1504 // name (can be null).
1505 String name = (String)enclosingInfo[1];
1506
1507 // the immediately enclosing method or constructor's
1508 // descriptor (null iff name is).
1509 String descriptor = (String)enclosingInfo[2];
1510 assert((name != null && descriptor != null) || name == descriptor);
1511 } catch (ClassCastException cce) {
1512 throw new InternalError("Invalid type in enclosing method information", cce);
1513 }
1514 }
1515
1516 EnclosingMethodInfo(Object[] enclosingInfo) {
1517 validate(enclosingInfo);
1518 this.enclosingClass = (Class<?>)enclosingInfo[0];
1519 this.name = (String)enclosingInfo[1];
1520 this.descriptor = (String)enclosingInfo[2];
1521 }
1522
1523 boolean isPartial() {
1524 return enclosingClass == null || name == null || descriptor == null;
1525 }
1526
1527 boolean isConstructor() { return !isPartial() && "<init>".equals(name); }
1528
1529 boolean isMethod() { return !isPartial() && !isConstructor() && !"<clinit>".equals(name); }
1530
1531 Class<?> getEnclosingClass() { return enclosingClass; }
1532
1533 String getName() { return name; }
1534
1535 String getDescriptor() { return descriptor; }
1536
1537 }
1538
1539 private static Class<?> toClass(Type o) {
1540 if (o instanceof GenericArrayType)
1541 return Array.newInstance(toClass(((GenericArrayType)o).getGenericComponentType()),
1542 0)
1543 .getClass();
1544 return (Class<?>)o;
1545 }
1546
1547 /**
1548 * If this {@code Class} object represents a local or anonymous
1549 * class within a constructor, returns a {@link
1550 * java.lang.reflect.Constructor Constructor} object representing
1551 * the immediately enclosing constructor of the underlying
1552 * class. Returns {@code null} otherwise. In particular, this
1553 * method returns {@code null} if the underlying class is a local
1554 * or anonymous class immediately enclosed by a class or
1555 * interface declaration, instance initializer or static initializer.
1556 *
1557 * @return the immediately enclosing constructor of the underlying class, if
1558 * that class is a local or anonymous class; otherwise {@code null}.
1559 * @throws SecurityException
1560 * If a security manager, <i>s</i>, is present and any of the
1561 * following conditions is met:
1562 *
1563 * <ul>
1564 *
1565 * <li> the caller's class loader is not the same as the
1566 * class loader of the enclosing class and invocation of
1567 * {@link SecurityManager#checkPermission
1568 * s.checkPermission} method with
1569 * {@code RuntimePermission("accessDeclaredMembers")}
1570 * denies access to the constructors within the enclosing class
1571 *
1572 * <li> the caller's class loader is not the same as or an
1573 * ancestor of the class loader for the enclosing class and
1574 * invocation of {@link SecurityManager#checkPackageAccess
1575 * s.checkPackageAccess()} denies access to the package
1576 * of the enclosing class
1577 *
1578 * </ul>
1579 * @since 1.5
1580 */
1581 @CallerSensitive
1582 public Constructor<?> getEnclosingConstructor() throws SecurityException {
1583 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1584
1585 if (enclosingInfo == null)
1586 return null;
1587 else {
1588 if (!enclosingInfo.isConstructor())
1589 return null;
1590
1591 ConstructorRepository typeInfo = ConstructorRepository.make(enclosingInfo.getDescriptor(),
1592 getFactory());
1593 Type [] parameterTypes = typeInfo.getParameterTypes();
1594 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length];
1595
1596 // Convert Types to Classes; returned types *should*
1597 // be class objects since the methodDescriptor's used
1598 // don't have generics information
1599 for(int i = 0; i < parameterClasses.length; i++)
1600 parameterClasses[i] = toClass(parameterTypes[i]);
1601
1602 // Perform access check
1603 final Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass();
1604 @SuppressWarnings("removal")
1605 SecurityManager sm = System.getSecurityManager();
1606 if (sm != null) {
1607 enclosingCandidate.checkMemberAccess(sm, Member.DECLARED,
1608 Reflection.getCallerClass(), true);
1609 }
1610
1611 Constructor<?>[] candidates = enclosingCandidate
1612 .privateGetDeclaredConstructors(false);
1613 /*
1614 * Loop over all declared constructors; match number
1615 * of and type of parameters.
1616 */
1617 ReflectionFactory fact = getReflectionFactory();
1618 for (Constructor<?> c : candidates) {
1619 if (arrayContentsEq(parameterClasses,
1620 fact.getExecutableSharedParameterTypes(c))) {
1621 return fact.copyConstructor(c);
1622 }
1623 }
1624
1625 throw new InternalError("Enclosing constructor not found");
1626 }
1627 }
1628
1629
1630 /**
1631 * If the class or interface represented by this {@code Class} object
1632 * is a member of another class, returns the {@code Class} object
1633 * representing the class in which it was declared. This method returns
1634 * null if this class or interface is not a member of any other class. If
1635 * this {@code Class} object represents an array class, a primitive
1636 * type, or void, then this method returns null.
1637 *
1638 * @return the declaring class for this class
1639 * @throws SecurityException
1640 * If a security manager, <i>s</i>, is present and the caller's
1641 * class loader is not the same as or an ancestor of the class
1642 * loader for the declaring class and invocation of {@link
1643 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
1644 * denies access to the package of the declaring class
1645 * @since 1.1
1646 */
1647 @CallerSensitive
1648 public Class<?> getDeclaringClass() throws SecurityException {
1649 final Class<?> candidate = getDeclaringClass0();
1650
1651 if (candidate != null) {
1652 @SuppressWarnings("removal")
1653 SecurityManager sm = System.getSecurityManager();
1654 if (sm != null) {
1655 candidate.checkPackageAccess(sm,
1656 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
1657 }
1658 }
1659 return candidate;
1660 }
1661
1662 private native Class<?> getDeclaringClass0();
1663
1664
1665 /**
1666 * Returns the immediately enclosing class of the underlying
1667 * class. If the underlying class is a top level class this
1668 * method returns {@code null}.
1669 * @return the immediately enclosing class of the underlying class
1670 * @throws SecurityException
1671 * If a security manager, <i>s</i>, is present and the caller's
1672 * class loader is not the same as or an ancestor of the class
1673 * loader for the enclosing class and invocation of {@link
1674 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
1675 * denies access to the package of the enclosing class
1676 * @since 1.5
1677 */
1678 @CallerSensitive
1679 public Class<?> getEnclosingClass() throws SecurityException {
1680 // There are five kinds of classes (or interfaces):
1681 // a) Top level classes
1682 // b) Nested classes (static member classes)
1683 // c) Inner classes (non-static member classes)
1684 // d) Local classes (named classes declared within a method)
1685 // e) Anonymous classes
1686
1687
1688 // JVM Spec 4.7.7: A class must have an EnclosingMethod
1689 // attribute if and only if it is a local class or an
1690 // anonymous class.
1691 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1692 Class<?> enclosingCandidate;
1693
1694 if (enclosingInfo == null) {
1695 // This is a top level or a nested class or an inner class (a, b, or c)
1696 enclosingCandidate = getDeclaringClass0();
1697 } else {
1698 Class<?> enclosingClass = enclosingInfo.getEnclosingClass();
1699 // This is a local class or an anonymous class (d or e)
1700 if (enclosingClass == this || enclosingClass == null)
1701 throw new InternalError("Malformed enclosing method information");
1702 else
1703 enclosingCandidate = enclosingClass;
1704 }
1705
1706 if (enclosingCandidate != null) {
1707 @SuppressWarnings("removal")
1708 SecurityManager sm = System.getSecurityManager();
1709 if (sm != null) {
1710 enclosingCandidate.checkPackageAccess(sm,
1711 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
1712 }
1713 }
1714 return enclosingCandidate;
1715 }
1716
1717 /**
1718 * Returns the simple name of the underlying class as given in the
1719 * source code. An empty string is returned if the underlying class is
1720 * {@linkplain #isAnonymousClass() anonymous}.
1721 * A {@linkplain #isSynthetic() synthetic class}, one not present
1722 * in source code, can have a non-empty name including special
1723 * characters, such as "{@code $}".
1724 *
1725 * <p>The simple name of an {@linkplain #isArray() array class} is the simple name of the
1726 * component type with "[]" appended. In particular the simple
1727 * name of an array class whose component type is anonymous is "[]".
1728 *
1729 * @return the simple name of the underlying class
1730 * @since 1.5
1731 */
1732 public String getSimpleName() {
1733 ReflectionData<T> rd = reflectionData();
1734 String simpleName = rd.simpleName;
1735 if (simpleName == null) {
1736 rd.simpleName = simpleName = getSimpleName0();
1737 }
1738 return simpleName;
1739 }
1740
1741 private String getSimpleName0() {
1742 if (isArray()) {
1743 return getComponentType().getSimpleName().concat("[]");
1744 }
1745 String simpleName = getSimpleBinaryName();
1746 if (simpleName == null) { // top level class
1747 simpleName = getName();
1748 simpleName = simpleName.substring(simpleName.lastIndexOf('.') + 1); // strip the package name
1749 }
1750 return simpleName;
1751 }
1752
1753 /**
1754 * Return an informative string for the name of this class or interface.
1755 *
1756 * @return an informative string for the name of this class or interface
1757 * @since 1.8
1758 */
1759 public String getTypeName() {
1760 if (isArray()) {
1761 try {
1762 Class<?> cl = this;
1763 int dimensions = 0;
1764 do {
1765 dimensions++;
1766 cl = cl.getComponentType();
1767 } while (cl.isArray());
1768 return cl.getName().concat("[]".repeat(dimensions));
1769 } catch (Throwable e) { /*FALLTHRU*/ }
1770 }
1771 return getName();
1772 }
1773
1774 /**
1775 * Returns the canonical name of the underlying class as
1776 * defined by <cite>The Java Language Specification</cite>.
1777 * Returns {@code null} if the underlying class does not have a canonical
1778 * name. Classes without canonical names include:
1779 * <ul>
1780 * <li>a {@linkplain #isLocalClass() local class}
1781 * <li>a {@linkplain #isAnonymousClass() anonymous class}
1782 * <li>a {@linkplain #isHidden() hidden class}
1783 * <li>an array whose component type does not have a canonical name</li>
1784 * </ul>
1785 *
1786 * The canonical name for a primitive class is the keyword for the
1787 * corresponding primitive type ({@code byte}, {@code short},
1788 * {@code char}, {@code int}, and so on).
1789 *
1790 * <p>An array type has a canonical name if and only if its
1791 * component type has a canonical name. When an array type has a
1792 * canonical name, it is equal to the canonical name of the
1793 * component type followed by "{@code []}".
1794 *
1795 * @return the canonical name of the underlying class if it exists, and
1796 * {@code null} otherwise.
1797 * @jls 6.7 Fully Qualified Names and Canonical Names
1798 * @since 1.5
1799 */
1800 public String getCanonicalName() {
1801 ReflectionData<T> rd = reflectionData();
1802 String canonicalName = rd.canonicalName;
1803 if (canonicalName == null) {
1804 rd.canonicalName = canonicalName = getCanonicalName0();
1805 }
1806 return canonicalName == ReflectionData.NULL_SENTINEL? null : canonicalName;
1807 }
1808
1809 private String getCanonicalName0() {
1810 if (isArray()) {
1811 String canonicalName = getComponentType().getCanonicalName();
1812 if (canonicalName != null)
1813 return canonicalName.concat("[]");
1814 else
1815 return ReflectionData.NULL_SENTINEL;
1816 }
1817 if (isHidden() || isLocalOrAnonymousClass())
1818 return ReflectionData.NULL_SENTINEL;
1819 Class<?> enclosingClass = getEnclosingClass();
1820 if (enclosingClass == null) { // top level class
1821 return getName();
1822 } else {
1823 String enclosingName = enclosingClass.getCanonicalName();
1824 if (enclosingName == null)
1825 return ReflectionData.NULL_SENTINEL;
1826 String simpleName = getSimpleName();
1827 return new StringBuilder(enclosingName.length() + simpleName.length() + 1)
1828 .append(enclosingName)
1829 .append('.')
1830 .append(simpleName)
1831 .toString();
1832 }
1833 }
1834
1835 /**
1836 * Returns {@code true} if and only if the underlying class
1837 * is an anonymous class.
1838 *
1839 * @apiNote
1840 * An anonymous class is not a {@linkplain #isHidden() hidden class}.
1841 *
1842 * @return {@code true} if and only if this class is an anonymous class.
1843 * @since 1.5
1844 * @jls 15.9.5 Anonymous Class Declarations
1845 */
1846 public boolean isAnonymousClass() {
1847 return !isArray() && isLocalOrAnonymousClass() &&
1848 getSimpleBinaryName0() == null;
1849 }
1850
1851 /**
1852 * Returns {@code true} if and only if the underlying class
1853 * is a local class.
1854 *
1855 * @return {@code true} if and only if this class is a local class.
1856 * @since 1.5
1857 * @jls 14.3 Local Class Declarations
1858 */
1859 public boolean isLocalClass() {
1860 return isLocalOrAnonymousClass() &&
1861 (isArray() || getSimpleBinaryName0() != null);
1862 }
1863
1864 /**
1865 * Returns {@code true} if and only if the underlying class
1866 * is a member class.
1867 *
1868 * @return {@code true} if and only if this class is a member class.
1869 * @since 1.5
1870 * @jls 8.5 Member Type Declarations
1871 */
1872 public boolean isMemberClass() {
1873 return !isLocalOrAnonymousClass() && getDeclaringClass0() != null;
1874 }
1875
1876 /**
1877 * Returns the "simple binary name" of the underlying class, i.e.,
1878 * the binary name without the leading enclosing class name.
1879 * Returns {@code null} if the underlying class is a top level
1880 * class.
1881 */
1882 private String getSimpleBinaryName() {
1883 if (isTopLevelClass())
1884 return null;
1885 String name = getSimpleBinaryName0();
1886 if (name == null) // anonymous class
1887 return "";
1888 return name;
1889 }
1890
1891 private native String getSimpleBinaryName0();
1892
1893 /**
1894 * Returns {@code true} if this is a top level class. Returns {@code false}
1895 * otherwise.
1896 */
1897 private boolean isTopLevelClass() {
1898 return !isLocalOrAnonymousClass() && getDeclaringClass0() == null;
1899 }
1900
1901 /**
1902 * Returns {@code true} if this is a local class or an anonymous
1903 * class. Returns {@code false} otherwise.
1904 */
1905 private boolean isLocalOrAnonymousClass() {
1906 // JVM Spec 4.7.7: A class must have an EnclosingMethod
1907 // attribute if and only if it is a local class or an
1908 // anonymous class.
1909 return hasEnclosingMethodInfo();
1910 }
1911
1912 private boolean hasEnclosingMethodInfo() {
1913 Object[] enclosingInfo = getEnclosingMethod0();
1914 if (enclosingInfo != null) {
1915 EnclosingMethodInfo.validate(enclosingInfo);
1916 return true;
1917 }
1918 return false;
1919 }
1920
1921 /**
1922 * Returns an array containing {@code Class} objects representing all
1923 * the public classes and interfaces that are members of the class
1924 * represented by this {@code Class} object. This includes public
1925 * class and interface members inherited from superclasses and public class
1926 * and interface members declared by the class. This method returns an
1927 * array of length 0 if this {@code Class} object has no public member
1928 * classes or interfaces. This method also returns an array of length 0 if
1929 * this {@code Class} object represents a primitive type, an array
1930 * class, or void.
1931 *
1932 * @return the array of {@code Class} objects representing the public
1933 * members of this class
1934 * @throws SecurityException
1935 * If a security manager, <i>s</i>, is present and
1936 * the caller's class loader is not the same as or an
1937 * ancestor of the class loader for the current class and
1938 * invocation of {@link SecurityManager#checkPackageAccess
1939 * s.checkPackageAccess()} denies access to the package
1940 * of this class.
1941 *
1942 * @since 1.1
1943 */
1944 @SuppressWarnings("removal")
1945 @CallerSensitive
1946 public Class<?>[] getClasses() {
1947 SecurityManager sm = System.getSecurityManager();
1948 if (sm != null) {
1949 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), false);
1950 }
1951
1952 // Privileged so this implementation can look at DECLARED classes,
1953 // something the caller might not have privilege to do. The code here
1954 // is allowed to look at DECLARED classes because (1) it does not hand
1955 // out anything other than public members and (2) public member access
1956 // has already been ok'd by the SecurityManager.
1957
1958 return java.security.AccessController.doPrivileged(
1959 new java.security.PrivilegedAction<>() {
1960 public Class<?>[] run() {
1961 List<Class<?>> list = new ArrayList<>();
1962 Class<?> currentClass = Class.this;
1963 while (currentClass != null) {
1964 for (Class<?> m : currentClass.getDeclaredClasses()) {
1965 if (Modifier.isPublic(m.getModifiers())) {
1966 list.add(m);
1967 }
1968 }
1969 currentClass = currentClass.getSuperclass();
1970 }
1971 return list.toArray(new Class<?>[0]);
1972 }
1973 });
1974 }
1975
1976
1977 /**
1978 * Returns an array containing {@code Field} objects reflecting all
1979 * the accessible public fields of the class or interface represented by
1980 * this {@code Class} object.
1981 *
1982 * <p> If this {@code Class} object represents a class or interface with
1983 * no accessible public fields, then this method returns an array of length
1984 * 0.
1985 *
1986 * <p> If this {@code Class} object represents a class, then this method
1987 * returns the public fields of the class and of all its superclasses and
1988 * superinterfaces.
1989 *
1990 * <p> If this {@code Class} object represents an interface, then this
1991 * method returns the fields of the interface and of all its
1992 * superinterfaces.
1993 *
1994 * <p> If this {@code Class} object represents an array type, a primitive
1995 * type, or void, then this method returns an array of length 0.
1996 *
1997 * <p> The elements in the returned array are not sorted and are not in any
1998 * particular order.
1999 *
2000 * @return the array of {@code Field} objects representing the
2001 * public fields
2002 * @throws SecurityException
2003 * If a security manager, <i>s</i>, is present and
2004 * the caller's class loader is not the same as or an
2005 * ancestor of the class loader for the current class and
2006 * invocation of {@link SecurityManager#checkPackageAccess
2007 * s.checkPackageAccess()} denies access to the package
2008 * of this class.
2009 *
2010 * @since 1.1
2011 * @jls 8.2 Class Members
2012 * @jls 8.3 Field Declarations
2013 */
2014 @CallerSensitive
2015 public Field[] getFields() throws SecurityException {
2016 @SuppressWarnings("removal")
2017 SecurityManager sm = System.getSecurityManager();
2018 if (sm != null) {
2019 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2020 }
2021 return copyFields(privateGetPublicFields());
2022 }
2023
2024
2025 /**
2026 * Returns an array containing {@code Method} objects reflecting all the
2027 * public methods of the class or interface represented by this {@code
2028 * Class} object, including those declared by the class or interface and
2029 * those inherited from superclasses and superinterfaces.
2030 *
2031 * <p> If this {@code Class} object represents an array type, then the
2032 * returned array has a {@code Method} object for each of the public
2033 * methods inherited by the array type from {@code Object}. It does not
2034 * contain a {@code Method} object for {@code clone()}.
2035 *
2036 * <p> If this {@code Class} object represents an interface then the
2037 * returned array does not contain any implicitly declared methods from
2038 * {@code Object}. Therefore, if no methods are explicitly declared in
2039 * this interface or any of its superinterfaces then the returned array
2040 * has length 0. (Note that a {@code Class} object which represents a class
2041 * always has public methods, inherited from {@code Object}.)
2042 *
2043 * <p> The returned array never contains methods with names "{@code <init>}"
2044 * or "{@code <clinit>}".
2045 *
2046 * <p> The elements in the returned array are not sorted and are not in any
2047 * particular order.
2048 *
2049 * <p> Generally, the result is computed as with the following 4 step algorithm.
2050 * Let C be the class or interface represented by this {@code Class} object:
2051 * <ol>
2052 * <li> A union of methods is composed of:
2053 * <ol type="a">
2054 * <li> C's declared public instance and static methods as returned by
2055 * {@link #getDeclaredMethods()} and filtered to include only public
2056 * methods.</li>
2057 * <li> If C is a class other than {@code Object}, then include the result
2058 * of invoking this algorithm recursively on the superclass of C.</li>
2059 * <li> Include the results of invoking this algorithm recursively on all
2060 * direct superinterfaces of C, but include only instance methods.</li>
2061 * </ol></li>
2062 * <li> Union from step 1 is partitioned into subsets of methods with same
2063 * signature (name, parameter types) and return type.</li>
2064 * <li> Within each such subset only the most specific methods are selected.
2065 * Let method M be a method from a set of methods with same signature
2066 * and return type. M is most specific if there is no such method
2067 * N != M from the same set, such that N is more specific than M.
2068 * N is more specific than M if:
2069 * <ol type="a">
2070 * <li> N is declared by a class and M is declared by an interface; or</li>
2071 * <li> N and M are both declared by classes or both by interfaces and
2072 * N's declaring type is the same as or a subtype of M's declaring type
2073 * (clearly, if M's and N's declaring types are the same type, then
2074 * M and N are the same method).</li>
2075 * </ol></li>
2076 * <li> The result of this algorithm is the union of all selected methods from
2077 * step 3.</li>
2078 * </ol>
2079 *
2080 * @apiNote There may be more than one method with a particular name
2081 * and parameter types in a class because while the Java language forbids a
2082 * class to declare multiple methods with the same signature but different
2083 * return types, the Java virtual machine does not. This
2084 * increased flexibility in the virtual machine can be used to
2085 * implement various language features. For example, covariant
2086 * returns can be implemented with {@linkplain
2087 * java.lang.reflect.Method#isBridge bridge methods}; the bridge
2088 * method and the overriding method would have the same
2089 * signature but different return types.
2090 *
2091 * @return the array of {@code Method} objects representing the
2092 * public methods of this class
2093 * @throws SecurityException
2094 * If a security manager, <i>s</i>, is present and
2095 * the caller's class loader is not the same as or an
2096 * ancestor of the class loader for the current class and
2097 * invocation of {@link SecurityManager#checkPackageAccess
2098 * s.checkPackageAccess()} denies access to the package
2099 * of this class.
2100 *
2101 * @jls 8.2 Class Members
2102 * @jls 8.4 Method Declarations
2103 * @since 1.1
2104 */
2105 @CallerSensitive
2106 public Method[] getMethods() throws SecurityException {
2107 @SuppressWarnings("removal")
2108 SecurityManager sm = System.getSecurityManager();
2109 if (sm != null) {
2110 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2111 }
2112 return copyMethods(privateGetPublicMethods());
2113 }
2114
2115
2116 /**
2117 * Returns an array containing {@code Constructor} objects reflecting
2118 * all the public constructors of the class represented by this
2119 * {@code Class} object. An array of length 0 is returned if the
2120 * class has no public constructors, or if the class is an array class, or
2121 * if the class reflects a primitive type or void.
2122 *
2123 * @apiNote
2124 * While this method returns an array of {@code
2125 * Constructor<T>} objects (that is an array of constructors from
2126 * this class), the return type of this method is {@code
2127 * Constructor<?>[]} and <em>not</em> {@code Constructor<T>[]} as
2128 * might be expected. This less informative return type is
2129 * necessary since after being returned from this method, the
2130 * array could be modified to hold {@code Constructor} objects for
2131 * different classes, which would violate the type guarantees of
2132 * {@code Constructor<T>[]}.
2133 *
2134 * @return the array of {@code Constructor} objects representing the
2135 * public constructors of this class
2136 * @throws SecurityException
2137 * If a security manager, <i>s</i>, is present and
2138 * the caller's class loader is not the same as or an
2139 * ancestor of the class loader for the current class and
2140 * invocation of {@link SecurityManager#checkPackageAccess
2141 * s.checkPackageAccess()} denies access to the package
2142 * of this class.
2143 *
2144 * @see #getDeclaredConstructors()
2145 * @since 1.1
2146 */
2147 @CallerSensitive
2148 public Constructor<?>[] getConstructors() throws SecurityException {
2149 @SuppressWarnings("removal")
2150 SecurityManager sm = System.getSecurityManager();
2151 if (sm != null) {
2152 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2153 }
2154 return copyConstructors(privateGetDeclaredConstructors(true));
2155 }
2156
2157
2158 /**
2159 * Returns a {@code Field} object that reflects the specified public member
2160 * field of the class or interface represented by this {@code Class}
2161 * object. The {@code name} parameter is a {@code String} specifying the
2162 * simple name of the desired field.
2163 *
2164 * <p> The field to be reflected is determined by the algorithm that
2165 * follows. Let C be the class or interface represented by this {@code Class} object:
2166 *
2167 * <OL>
2168 * <LI> If C declares a public field with the name specified, that is the
2169 * field to be reflected.</LI>
2170 * <LI> If no field was found in step 1 above, this algorithm is applied
2171 * recursively to each direct superinterface of C. The direct
2172 * superinterfaces are searched in the order they were declared.</LI>
2173 * <LI> If no field was found in steps 1 and 2 above, and C has a
2174 * superclass S, then this algorithm is invoked recursively upon S.
2175 * If C has no superclass, then a {@code NoSuchFieldException}
2176 * is thrown.</LI>
2177 * </OL>
2178 *
2179 * <p> If this {@code Class} object represents an array type, then this
2180 * method does not find the {@code length} field of the array type.
2181 *
2182 * @param name the field name
2183 * @return the {@code Field} object of this class specified by
2184 * {@code name}
2185 * @throws NoSuchFieldException if a field with the specified name is
2186 * not found.
2187 * @throws NullPointerException if {@code name} is {@code null}
2188 * @throws SecurityException
2189 * If a security manager, <i>s</i>, is present and
2190 * the caller's class loader is not the same as or an
2191 * ancestor of the class loader for the current class and
2192 * invocation of {@link SecurityManager#checkPackageAccess
2193 * s.checkPackageAccess()} denies access to the package
2194 * of this class.
2195 *
2196 * @since 1.1
2197 * @jls 8.2 Class Members
2198 * @jls 8.3 Field Declarations
2199 */
2200 @CallerSensitive
2201 public Field getField(String name)
2202 throws NoSuchFieldException, SecurityException {
2203 Objects.requireNonNull(name);
2204 @SuppressWarnings("removal")
2205 SecurityManager sm = System.getSecurityManager();
2206 if (sm != null) {
2207 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2208 }
2209 Field field = getField0(name);
2210 if (field == null) {
2211 throw new NoSuchFieldException(name);
2212 }
2213 return getReflectionFactory().copyField(field);
2214 }
2215
2216
2217 /**
2218 * Returns a {@code Method} object that reflects the specified public
2219 * member method of the class or interface represented by this
2220 * {@code Class} object. The {@code name} parameter is a
2221 * {@code String} specifying the simple name of the desired method. The
2222 * {@code parameterTypes} parameter is an array of {@code Class}
2223 * objects that identify the method's formal parameter types, in declared
2224 * order. If {@code parameterTypes} is {@code null}, it is
2225 * treated as if it were an empty array.
2226 *
2227 * <p> If this {@code Class} object represents an array type, then this
2228 * method finds any public method inherited by the array type from
2229 * {@code Object} except method {@code clone()}.
2230 *
2231 * <p> If this {@code Class} object represents an interface then this
2232 * method does not find any implicitly declared method from
2233 * {@code Object}. Therefore, if no methods are explicitly declared in
2234 * this interface or any of its superinterfaces, then this method does not
2235 * find any method.
2236 *
2237 * <p> This method does not find any method with name "{@code <init>}" or
2238 * "{@code <clinit>}".
2239 *
2240 * <p> Generally, the method to be reflected is determined by the 4 step
2241 * algorithm that follows.
2242 * Let C be the class or interface represented by this {@code Class} object:
2243 * <ol>
2244 * <li> A union of methods is composed of:
2245 * <ol type="a">
2246 * <li> C's declared public instance and static methods as returned by
2247 * {@link #getDeclaredMethods()} and filtered to include only public
2248 * methods that match given {@code name} and {@code parameterTypes}</li>
2249 * <li> If C is a class other than {@code Object}, then include the result
2250 * of invoking this algorithm recursively on the superclass of C.</li>
2251 * <li> Include the results of invoking this algorithm recursively on all
2252 * direct superinterfaces of C, but include only instance methods.</li>
2253 * </ol></li>
2254 * <li> This union is partitioned into subsets of methods with same
2255 * return type (the selection of methods from step 1 also guarantees that
2256 * they have the same method name and parameter types).</li>
2257 * <li> Within each such subset only the most specific methods are selected.
2258 * Let method M be a method from a set of methods with same VM
2259 * signature (return type, name, parameter types).
2260 * M is most specific if there is no such method N != M from the same
2261 * set, such that N is more specific than M. N is more specific than M
2262 * if:
2263 * <ol type="a">
2264 * <li> N is declared by a class and M is declared by an interface; or</li>
2265 * <li> N and M are both declared by classes or both by interfaces and
2266 * N's declaring type is the same as or a subtype of M's declaring type
2267 * (clearly, if M's and N's declaring types are the same type, then
2268 * M and N are the same method).</li>
2269 * </ol></li>
2270 * <li> The result of this algorithm is chosen arbitrarily from the methods
2271 * with most specific return type among all selected methods from step 3.
2272 * Let R be a return type of a method M from the set of all selected methods
2273 * from step 3. M is a method with most specific return type if there is
2274 * no such method N != M from the same set, having return type S != R,
2275 * such that S is a subtype of R as determined by
2276 * R.class.{@link #isAssignableFrom}(S.class).
2277 * </ol>
2278 *
2279 * @apiNote There may be more than one method with matching name and
2280 * parameter types in a class because while the Java language forbids a
2281 * class to declare multiple methods with the same signature but different
2282 * return types, the Java virtual machine does not. This
2283 * increased flexibility in the virtual machine can be used to
2284 * implement various language features. For example, covariant
2285 * returns can be implemented with {@linkplain
2286 * java.lang.reflect.Method#isBridge bridge methods}; the bridge
2287 * method and the overriding method would have the same
2288 * signature but different return types. This method would return the
2289 * overriding method as it would have a more specific return type.
2290 *
2291 * @param name the name of the method
2292 * @param parameterTypes the list of parameters
2293 * @return the {@code Method} object that matches the specified
2294 * {@code name} and {@code parameterTypes}
2295 * @throws NoSuchMethodException if a matching method is not found
2296 * or if the name is "<init>"or "<clinit>".
2297 * @throws NullPointerException if {@code name} is {@code null}
2298 * @throws SecurityException
2299 * If a security manager, <i>s</i>, is present and
2300 * the caller's class loader is not the same as or an
2301 * ancestor of the class loader for the current class and
2302 * invocation of {@link SecurityManager#checkPackageAccess
2303 * s.checkPackageAccess()} denies access to the package
2304 * of this class.
2305 *
2306 * @jls 8.2 Class Members
2307 * @jls 8.4 Method Declarations
2308 * @since 1.1
2309 */
2310 @CallerSensitive
2311 public Method getMethod(String name, Class<?>... parameterTypes)
2312 throws NoSuchMethodException, SecurityException {
2313 Objects.requireNonNull(name);
2314 @SuppressWarnings("removal")
2315 SecurityManager sm = System.getSecurityManager();
2316 if (sm != null) {
2317 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2318 }
2319 Method method = getMethod0(name, parameterTypes);
2320 if (method == null) {
2321 throw new NoSuchMethodException(methodToString(name, parameterTypes));
2322 }
2323 return getReflectionFactory().copyMethod(method);
2324 }
2325
2326 /**
2327 * Returns a {@code Constructor} object that reflects the specified
2328 * public constructor of the class represented by this {@code Class}
2329 * object. The {@code parameterTypes} parameter is an array of
2330 * {@code Class} objects that identify the constructor's formal
2331 * parameter types, in declared order.
2332 *
2333 * If this {@code Class} object represents an inner class
2334 * declared in a non-static context, the formal parameter types
2335 * include the explicit enclosing instance as the first parameter.
2336 *
2337 * <p> The constructor to reflect is the public constructor of the class
2338 * represented by this {@code Class} object whose formal parameter
2339 * types match those specified by {@code parameterTypes}.
2340 *
2341 * @param parameterTypes the parameter array
2342 * @return the {@code Constructor} object of the public constructor that
2343 * matches the specified {@code parameterTypes}
2344 * @throws NoSuchMethodException if a matching constructor is not found,
2345 * including when this {@code Class} object represents
2346 * an interface, a primitive type, an array class, or void.
2347 * @throws SecurityException
2348 * If a security manager, <i>s</i>, is present and
2349 * the caller's class loader is not the same as or an
2350 * ancestor of the class loader for the current class and
2351 * invocation of {@link SecurityManager#checkPackageAccess
2352 * s.checkPackageAccess()} denies access to the package
2353 * of this class.
2354 *
2355 * @see #getDeclaredConstructor(Class<?>[])
2356 * @since 1.1
2357 */
2358 @CallerSensitive
2359 public Constructor<T> getConstructor(Class<?>... parameterTypes)
2360 throws NoSuchMethodException, SecurityException
2361 {
2362 @SuppressWarnings("removal")
2363 SecurityManager sm = System.getSecurityManager();
2364 if (sm != null) {
2365 checkMemberAccess(sm, Member.PUBLIC, Reflection.getCallerClass(), true);
2366 }
2367 return getReflectionFactory().copyConstructor(
2368 getConstructor0(parameterTypes, Member.PUBLIC));
2369 }
2370
2371
2372 /**
2373 * Returns an array of {@code Class} objects reflecting all the
2374 * classes and interfaces declared as members of the class represented by
2375 * this {@code Class} object. This includes public, protected, default
2376 * (package) access, and private classes and interfaces declared by the
2377 * class, but excludes inherited classes and interfaces. This method
2378 * returns an array of length 0 if the class declares no classes or
2379 * interfaces as members, or if this {@code Class} object represents a
2380 * primitive type, an array class, or void.
2381 *
2382 * @return the array of {@code Class} objects representing all the
2383 * declared members of this class
2384 * @throws SecurityException
2385 * If a security manager, <i>s</i>, is present and any of the
2386 * following conditions is met:
2387 *
2388 * <ul>
2389 *
2390 * <li> the caller's class loader is not the same as the
2391 * class loader of this class and invocation of
2392 * {@link SecurityManager#checkPermission
2393 * s.checkPermission} method with
2394 * {@code RuntimePermission("accessDeclaredMembers")}
2395 * denies access to the declared classes within this class
2396 *
2397 * <li> the caller's class loader is not the same as or an
2398 * ancestor of the class loader for the current class and
2399 * invocation of {@link SecurityManager#checkPackageAccess
2400 * s.checkPackageAccess()} denies access to the package
2401 * of this class
2402 *
2403 * </ul>
2404 *
2405 * @since 1.1
2406 * @jls 8.5 Member Type Declarations
2407 */
2408 @CallerSensitive
2409 public Class<?>[] getDeclaredClasses() throws SecurityException {
2410 @SuppressWarnings("removal")
2411 SecurityManager sm = System.getSecurityManager();
2412 if (sm != null) {
2413 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), false);
2414 }
2415 return getDeclaredClasses0();
2416 }
2417
2418
2419 /**
2420 * Returns an array of {@code Field} objects reflecting all the fields
2421 * declared by the class or interface represented by this
2422 * {@code Class} object. This includes public, protected, default
2423 * (package) access, and private fields, but excludes inherited fields.
2424 *
2425 * <p> If this {@code Class} object represents a class or interface with no
2426 * declared fields, then this method returns an array of length 0.
2427 *
2428 * <p> If this {@code Class} object represents an array type, a primitive
2429 * type, or void, then this method returns an array of length 0.
2430 *
2431 * <p> The elements in the returned array are not sorted and are not in any
2432 * particular order.
2433 *
2434 * @return the array of {@code Field} objects representing all the
2435 * declared fields of this class
2436 * @throws SecurityException
2437 * If a security manager, <i>s</i>, is present and any of the
2438 * following conditions is met:
2439 *
2440 * <ul>
2441 *
2442 * <li> the caller's class loader is not the same as the
2443 * class loader of this class and invocation of
2444 * {@link SecurityManager#checkPermission
2445 * s.checkPermission} method with
2446 * {@code RuntimePermission("accessDeclaredMembers")}
2447 * denies access to the declared fields within this class
2448 *
2449 * <li> the caller's class loader is not the same as or an
2450 * ancestor of the class loader for the current class and
2451 * invocation of {@link SecurityManager#checkPackageAccess
2452 * s.checkPackageAccess()} denies access to the package
2453 * of this class
2454 *
2455 * </ul>
2456 *
2457 * @since 1.1
2458 * @jls 8.2 Class Members
2459 * @jls 8.3 Field Declarations
2460 */
2461 @CallerSensitive
2462 public Field[] getDeclaredFields() throws SecurityException {
2463 @SuppressWarnings("removal")
2464 SecurityManager sm = System.getSecurityManager();
2465 if (sm != null) {
2466 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2467 }
2468 return copyFields(privateGetDeclaredFields(false));
2469 }
2470
2471 /**
2472 * Returns an array of {@code RecordComponent} objects representing all the
2473 * record components of this record class, or {@code null} if this class is
2474 * not a record class.
2475 *
2476 * <p> The components are returned in the same order that they are declared
2477 * in the record header. The array is empty if this record class has no
2478 * components. If the class is not a record class, that is {@link
2479 * #isRecord()} returns {@code false}, then this method returns {@code null}.
2480 * Conversely, if {@link #isRecord()} returns {@code true}, then this method
2481 * returns a non-null value.
2482 *
2483 * @apiNote
2484 * <p> The following method can be used to find the record canonical constructor:
2485 *
2486 * <pre>{@code
2487 * static <T extends Record> Constructor<T> getCanonicalConstructor(Class<T> cls)
2488 * throws NoSuchMethodException {
2489 * Class<?>[] paramTypes =
2490 * Arrays.stream(cls.getRecordComponents())
2491 * .map(RecordComponent::getType)
2492 * .toArray(Class<?>[]::new);
2493 * return cls.getDeclaredConstructor(paramTypes);
2494 * }}</pre>
2495 *
2496 * @return An array of {@code RecordComponent} objects representing all the
2497 * record components of this record class, or {@code null} if this
2498 * class is not a record class
2499 * @throws SecurityException
2500 * If a security manager, <i>s</i>, is present and any of the
2501 * following conditions is met:
2502 *
2503 * <ul>
2504 *
2505 * <li> the caller's class loader is not the same as the
2506 * class loader of this class and invocation of
2507 * {@link SecurityManager#checkPermission
2508 * s.checkPermission} method with
2509 * {@code RuntimePermission("accessDeclaredMembers")}
2510 * denies access to the declared methods within this class
2511 *
2512 * <li> the caller's class loader is not the same as or an
2513 * ancestor of the class loader for the current class and
2514 * invocation of {@link SecurityManager#checkPackageAccess
2515 * s.checkPackageAccess()} denies access to the package
2516 * of this class
2517 *
2518 * </ul>
2519 *
2520 * @jls 8.10 Record Classes
2521 * @since 16
2522 */
2523 @CallerSensitive
2524 public RecordComponent[] getRecordComponents() {
2525 @SuppressWarnings("removal")
2526 SecurityManager sm = System.getSecurityManager();
2527 if (sm != null) {
2528 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2529 }
2530 if (!isRecord()) {
2531 return null;
2532 }
2533 return getRecordComponents0();
2534 }
2535
2536 /**
2537 * Returns an array containing {@code Method} objects reflecting all the
2538 * declared methods of the class or interface represented by this {@code
2539 * Class} object, including public, protected, default (package)
2540 * access, and private methods, but excluding inherited methods.
2541 * The declared methods may include methods <em>not</em> in the
2542 * source of the class or interface, including {@linkplain
2543 * Method#isBridge bridge methods} and other {@linkplain
2544 * Executable#isSynthetic synthetic} methods added by compilers.
2545 *
2546 * <p> If this {@code Class} object represents a class or interface that
2547 * has multiple declared methods with the same name and parameter types,
2548 * but different return types, then the returned array has a {@code Method}
2549 * object for each such method.
2550 *
2551 * <p> If this {@code Class} object represents a class or interface that
2552 * has a class initialization method {@code <clinit>}, then the returned
2553 * array does <em>not</em> have a corresponding {@code Method} object.
2554 *
2555 * <p> If this {@code Class} object represents a class or interface with no
2556 * declared methods, then the returned array has length 0.
2557 *
2558 * <p> If this {@code Class} object represents an array type, a primitive
2559 * type, or void, then the returned array has length 0.
2560 *
2561 * <p> The elements in the returned array are not sorted and are not in any
2562 * particular order.
2563 *
2564 * @return the array of {@code Method} objects representing all the
2565 * declared methods of this class
2566 * @throws SecurityException
2567 * If a security manager, <i>s</i>, is present and any of the
2568 * following conditions is met:
2569 *
2570 * <ul>
2571 *
2572 * <li> the caller's class loader is not the same as the
2573 * class loader of this class and invocation of
2574 * {@link SecurityManager#checkPermission
2575 * s.checkPermission} method with
2576 * {@code RuntimePermission("accessDeclaredMembers")}
2577 * denies access to the declared methods within this class
2578 *
2579 * <li> the caller's class loader is not the same as or an
2580 * ancestor of the class loader for the current class and
2581 * invocation of {@link SecurityManager#checkPackageAccess
2582 * s.checkPackageAccess()} denies access to the package
2583 * of this class
2584 *
2585 * </ul>
2586 *
2587 * @jls 8.2 Class Members
2588 * @jls 8.4 Method Declarations
2589 * @see <a
2590 * href="{@docRoot}/java.base/java/lang/reflect/package-summary.html#LanguageJvmModel">Java
2591 * programming language and JVM modeling in core reflection</a>
2592 * @since 1.1
2593 */
2594 @CallerSensitive
2595 public Method[] getDeclaredMethods() throws SecurityException {
2596 @SuppressWarnings("removal")
2597 SecurityManager sm = System.getSecurityManager();
2598 if (sm != null) {
2599 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2600 }
2601 return copyMethods(privateGetDeclaredMethods(false));
2602 }
2603
2604 /**
2605 * Returns an array of {@code Constructor} objects reflecting all the
2606 * constructors implicitly or explicitly declared by the class represented by this
2607 * {@code Class} object. These are public, protected, default
2608 * (package) access, and private constructors. The elements in the array
2609 * returned are not sorted and are not in any particular order. If the
2610 * class has a default constructor (JLS {@jls 8.8.9}), it is included in the returned array.
2611 * If a record class has a canonical constructor (JLS {@jls
2612 * 8.10.4.1}, {@jls 8.10.4.2}), it is included in the returned array.
2613 *
2614 * This method returns an array of length 0 if this {@code Class}
2615 * object represents an interface, a primitive type, an array class, or
2616 * void.
2617 *
2618 * @return the array of {@code Constructor} objects representing all the
2619 * declared constructors of this class
2620 * @throws SecurityException
2621 * If a security manager, <i>s</i>, is present and any of the
2622 * following conditions is met:
2623 *
2624 * <ul>
2625 *
2626 * <li> the caller's class loader is not the same as the
2627 * class loader of this class and invocation of
2628 * {@link SecurityManager#checkPermission
2629 * s.checkPermission} method with
2630 * {@code RuntimePermission("accessDeclaredMembers")}
2631 * denies access to the declared constructors within this class
2632 *
2633 * <li> the caller's class loader is not the same as or an
2634 * ancestor of the class loader for the current class and
2635 * invocation of {@link SecurityManager#checkPackageAccess
2636 * s.checkPackageAccess()} denies access to the package
2637 * of this class
2638 *
2639 * </ul>
2640 *
2641 * @since 1.1
2642 * @see #getConstructors()
2643 * @jls 8.8 Constructor Declarations
2644 */
2645 @CallerSensitive
2646 public Constructor<?>[] getDeclaredConstructors() throws SecurityException {
2647 @SuppressWarnings("removal")
2648 SecurityManager sm = System.getSecurityManager();
2649 if (sm != null) {
2650 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2651 }
2652 return copyConstructors(privateGetDeclaredConstructors(false));
2653 }
2654
2655
2656 /**
2657 * Returns a {@code Field} object that reflects the specified declared
2658 * field of the class or interface represented by this {@code Class}
2659 * object. The {@code name} parameter is a {@code String} that specifies
2660 * the simple name of the desired field.
2661 *
2662 * <p> If this {@code Class} object represents an array type, then this
2663 * method does not find the {@code length} field of the array type.
2664 *
2665 * @param name the name of the field
2666 * @return the {@code Field} object for the specified field in this
2667 * class
2668 * @throws NoSuchFieldException if a field with the specified name is
2669 * not found.
2670 * @throws NullPointerException if {@code name} is {@code null}
2671 * @throws SecurityException
2672 * If a security manager, <i>s</i>, is present and any of the
2673 * following conditions is met:
2674 *
2675 * <ul>
2676 *
2677 * <li> the caller's class loader is not the same as the
2678 * class loader of this class and invocation of
2679 * {@link SecurityManager#checkPermission
2680 * s.checkPermission} method with
2681 * {@code RuntimePermission("accessDeclaredMembers")}
2682 * denies access to the declared field
2683 *
2684 * <li> the caller's class loader is not the same as or an
2685 * ancestor of the class loader for the current class and
2686 * invocation of {@link SecurityManager#checkPackageAccess
2687 * s.checkPackageAccess()} denies access to the package
2688 * of this class
2689 *
2690 * </ul>
2691 *
2692 * @since 1.1
2693 * @jls 8.2 Class Members
2694 * @jls 8.3 Field Declarations
2695 */
2696 @CallerSensitive
2697 public Field getDeclaredField(String name)
2698 throws NoSuchFieldException, SecurityException {
2699 Objects.requireNonNull(name);
2700 @SuppressWarnings("removal")
2701 SecurityManager sm = System.getSecurityManager();
2702 if (sm != null) {
2703 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2704 }
2705 Field field = searchFields(privateGetDeclaredFields(false), name);
2706 if (field == null) {
2707 throw new NoSuchFieldException(name);
2708 }
2709 return getReflectionFactory().copyField(field);
2710 }
2711
2712
2713 /**
2714 * Returns a {@code Method} object that reflects the specified
2715 * declared method of the class or interface represented by this
2716 * {@code Class} object. The {@code name} parameter is a
2717 * {@code String} that specifies the simple name of the desired
2718 * method, and the {@code parameterTypes} parameter is an array of
2719 * {@code Class} objects that identify the method's formal parameter
2720 * types, in declared order. If more than one method with the same
2721 * parameter types is declared in a class, and one of these methods has a
2722 * return type that is more specific than any of the others, that method is
2723 * returned; otherwise one of the methods is chosen arbitrarily. If the
2724 * name is "<init>"or "<clinit>" a {@code NoSuchMethodException}
2725 * is raised.
2726 *
2727 * <p> If this {@code Class} object represents an array type, then this
2728 * method does not find the {@code clone()} method.
2729 *
2730 * @param name the name of the method
2731 * @param parameterTypes the parameter array
2732 * @return the {@code Method} object for the method of this class
2733 * matching the specified name and parameters
2734 * @throws NoSuchMethodException if a matching method is not found.
2735 * @throws NullPointerException if {@code name} is {@code null}
2736 * @throws SecurityException
2737 * If a security manager, <i>s</i>, is present and any of the
2738 * following conditions is met:
2739 *
2740 * <ul>
2741 *
2742 * <li> the caller's class loader is not the same as the
2743 * class loader of this class and invocation of
2744 * {@link SecurityManager#checkPermission
2745 * s.checkPermission} method with
2746 * {@code RuntimePermission("accessDeclaredMembers")}
2747 * denies access to the declared method
2748 *
2749 * <li> the caller's class loader is not the same as or an
2750 * ancestor of the class loader for the current class and
2751 * invocation of {@link SecurityManager#checkPackageAccess
2752 * s.checkPackageAccess()} denies access to the package
2753 * of this class
2754 *
2755 * </ul>
2756 *
2757 * @jls 8.2 Class Members
2758 * @jls 8.4 Method Declarations
2759 * @since 1.1
2760 */
2761 @CallerSensitive
2762 public Method getDeclaredMethod(String name, Class<?>... parameterTypes)
2763 throws NoSuchMethodException, SecurityException {
2764 Objects.requireNonNull(name);
2765 @SuppressWarnings("removal")
2766 SecurityManager sm = System.getSecurityManager();
2767 if (sm != null) {
2768 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2769 }
2770 Method method = searchMethods(privateGetDeclaredMethods(false), name, parameterTypes);
2771 if (method == null) {
2772 throw new NoSuchMethodException(methodToString(name, parameterTypes));
2773 }
2774 return getReflectionFactory().copyMethod(method);
2775 }
2776
2777 /**
2778 * Returns the list of {@code Method} objects for the declared public
2779 * methods of this class or interface that have the specified method name
2780 * and parameter types.
2781 *
2782 * @param name the name of the method
2783 * @param parameterTypes the parameter array
2784 * @return the list of {@code Method} objects for the public methods of
2785 * this class matching the specified name and parameters
2786 */
2787 List<Method> getDeclaredPublicMethods(String name, Class<?>... parameterTypes) {
2788 Method[] methods = privateGetDeclaredMethods(/* publicOnly */ true);
2789 ReflectionFactory factory = getReflectionFactory();
2790 List<Method> result = new ArrayList<>();
2791 for (Method method : methods) {
2792 if (method.getName().equals(name)
2793 && Arrays.equals(
2794 factory.getExecutableSharedParameterTypes(method),
2795 parameterTypes)) {
2796 result.add(factory.copyMethod(method));
2797 }
2798 }
2799 return result;
2800 }
2801
2802 /**
2803 * Returns a {@code Constructor} object that reflects the specified
2804 * constructor of the class represented by this
2805 * {@code Class} object. The {@code parameterTypes} parameter is
2806 * an array of {@code Class} objects that identify the constructor's
2807 * formal parameter types, in declared order.
2808 *
2809 * If this {@code Class} object represents an inner class
2810 * declared in a non-static context, the formal parameter types
2811 * include the explicit enclosing instance as the first parameter.
2812 *
2813 * @param parameterTypes the parameter array
2814 * @return The {@code Constructor} object for the constructor with the
2815 * specified parameter list
2816 * @throws NoSuchMethodException if a matching constructor is not found,
2817 * including when this {@code Class} object represents
2818 * an interface, a primitive type, an array class, or void.
2819 * @throws SecurityException
2820 * If a security manager, <i>s</i>, is present and any of the
2821 * following conditions is met:
2822 *
2823 * <ul>
2824 *
2825 * <li> the caller's class loader is not the same as the
2826 * class loader of this class and invocation of
2827 * {@link SecurityManager#checkPermission
2828 * s.checkPermission} method with
2829 * {@code RuntimePermission("accessDeclaredMembers")}
2830 * denies access to the declared constructor
2831 *
2832 * <li> the caller's class loader is not the same as or an
2833 * ancestor of the class loader for the current class and
2834 * invocation of {@link SecurityManager#checkPackageAccess
2835 * s.checkPackageAccess()} denies access to the package
2836 * of this class
2837 *
2838 * </ul>
2839 *
2840 * @see #getConstructor(Class<?>[])
2841 * @since 1.1
2842 */
2843 @CallerSensitive
2844 public Constructor<T> getDeclaredConstructor(Class<?>... parameterTypes)
2845 throws NoSuchMethodException, SecurityException
2846 {
2847 @SuppressWarnings("removal")
2848 SecurityManager sm = System.getSecurityManager();
2849 if (sm != null) {
2850 checkMemberAccess(sm, Member.DECLARED, Reflection.getCallerClass(), true);
2851 }
2852
2853 return getReflectionFactory().copyConstructor(
2854 getConstructor0(parameterTypes, Member.DECLARED));
2855 }
2856
2857 /**
2858 * Finds a resource with a given name.
2859 *
2860 * <p> If this class is in a named {@link Module Module} then this method
2861 * will attempt to find the resource in the module. This is done by
2862 * delegating to the module's class loader {@link
2863 * ClassLoader#findResource(String,String) findResource(String,String)}
2864 * method, invoking it with the module name and the absolute name of the
2865 * resource. Resources in named modules are subject to the rules for
2866 * encapsulation specified in the {@code Module} {@link
2867 * Module#getResourceAsStream getResourceAsStream} method and so this
2868 * method returns {@code null} when the resource is a
2869 * non-"{@code .class}" resource in a package that is not open to the
2870 * caller's module.
2871 *
2872 * <p> Otherwise, if this class is not in a named module then the rules for
2873 * searching resources associated with a given class are implemented by the
2874 * defining {@linkplain ClassLoader class loader} of the class. This method
2875 * delegates to this {@code Class} object's class loader.
2876 * If this {@code Class} object was loaded by the bootstrap class loader,
2877 * the method delegates to {@link ClassLoader#getSystemResourceAsStream}.
2878 *
2879 * <p> Before delegation, an absolute resource name is constructed from the
2880 * given resource name using this algorithm:
2881 *
2882 * <ul>
2883 *
2884 * <li> If the {@code name} begins with a {@code '/'}
2885 * (<code>'\u002f'</code>), then the absolute name of the resource is the
2886 * portion of the {@code name} following the {@code '/'}.
2887 *
2888 * <li> Otherwise, the absolute name is of the following form:
2889 *
2890 * <blockquote>
2891 * {@code modified_package_name/name}
2892 * </blockquote>
2893 *
2894 * <p> Where the {@code modified_package_name} is the package name of this
2895 * object with {@code '/'} substituted for {@code '.'}
2896 * (<code>'\u002e'</code>).
2897 *
2898 * </ul>
2899 *
2900 * @param name name of the desired resource
2901 * @return A {@link java.io.InputStream} object; {@code null} if no
2902 * resource with this name is found, the resource is in a package
2903 * that is not {@linkplain Module#isOpen(String, Module) open} to at
2904 * least the caller module, or access to the resource is denied
2905 * by the security manager.
2906 * @throws NullPointerException If {@code name} is {@code null}
2907 *
2908 * @see Module#getResourceAsStream(String)
2909 * @since 1.1
2910 * @revised 9
2911 */
2912 @CallerSensitive
2913 public InputStream getResourceAsStream(String name) {
2914 name = resolveName(name);
2915
2916 Module thisModule = getModule();
2917 if (thisModule.isNamed()) {
2918 // check if resource can be located by caller
2919 if (Resources.canEncapsulate(name)
2920 && !isOpenToCaller(name, Reflection.getCallerClass())) {
2921 return null;
2922 }
2923
2924 // resource not encapsulated or in package open to caller
2925 String mn = thisModule.getName();
2926 ClassLoader cl = classLoader;
2927 try {
2928
2929 // special-case built-in class loaders to avoid the
2930 // need for a URL connection
2931 if (cl == null) {
2932 return BootLoader.findResourceAsStream(mn, name);
2933 } else if (cl instanceof BuiltinClassLoader) {
2934 return ((BuiltinClassLoader) cl).findResourceAsStream(mn, name);
2935 } else {
2936 URL url = cl.findResource(mn, name);
2937 return (url != null) ? url.openStream() : null;
2938 }
2939
2940 } catch (IOException | SecurityException e) {
2941 return null;
2942 }
2943 }
2944
2945 // unnamed module
2946 ClassLoader cl = classLoader;
2947 if (cl == null) {
2948 return ClassLoader.getSystemResourceAsStream(name);
2949 } else {
2950 return cl.getResourceAsStream(name);
2951 }
2952 }
2953
2954 /**
2955 * Finds a resource with a given name.
2956 *
2957 * <p> If this class is in a named {@link Module Module} then this method
2958 * will attempt to find the resource in the module. This is done by
2959 * delegating to the module's class loader {@link
2960 * ClassLoader#findResource(String,String) findResource(String,String)}
2961 * method, invoking it with the module name and the absolute name of the
2962 * resource. Resources in named modules are subject to the rules for
2963 * encapsulation specified in the {@code Module} {@link
2964 * Module#getResourceAsStream getResourceAsStream} method and so this
2965 * method returns {@code null} when the resource is a
2966 * non-"{@code .class}" resource in a package that is not open to the
2967 * caller's module.
2968 *
2969 * <p> Otherwise, if this class is not in a named module then the rules for
2970 * searching resources associated with a given class are implemented by the
2971 * defining {@linkplain ClassLoader class loader} of the class. This method
2972 * delegates to this {@code Class} object's class loader.
2973 * If this {@code Class} object was loaded by the bootstrap class loader,
2974 * the method delegates to {@link ClassLoader#getSystemResource}.
2975 *
2976 * <p> Before delegation, an absolute resource name is constructed from the
2977 * given resource name using this algorithm:
2978 *
2979 * <ul>
2980 *
2981 * <li> If the {@code name} begins with a {@code '/'}
2982 * (<code>'\u002f'</code>), then the absolute name of the resource is the
2983 * portion of the {@code name} following the {@code '/'}.
2984 *
2985 * <li> Otherwise, the absolute name is of the following form:
2986 *
2987 * <blockquote>
2988 * {@code modified_package_name/name}
2989 * </blockquote>
2990 *
2991 * <p> Where the {@code modified_package_name} is the package name of this
2992 * object with {@code '/'} substituted for {@code '.'}
2993 * (<code>'\u002e'</code>).
2994 *
2995 * </ul>
2996 *
2997 * @param name name of the desired resource
2998 * @return A {@link java.net.URL} object; {@code null} if no resource with
2999 * this name is found, the resource cannot be located by a URL, the
3000 * resource is in a package that is not
3001 * {@linkplain Module#isOpen(String, Module) open} to at least the caller
3002 * module, or access to the resource is denied by the security
3003 * manager.
3004 * @throws NullPointerException If {@code name} is {@code null}
3005 * @since 1.1
3006 * @revised 9
3007 */
3008 @CallerSensitive
3009 public URL getResource(String name) {
3010 name = resolveName(name);
3011
3012 Module thisModule = getModule();
3013 if (thisModule.isNamed()) {
3014 // check if resource can be located by caller
3015 if (Resources.canEncapsulate(name)
3016 && !isOpenToCaller(name, Reflection.getCallerClass())) {
3017 return null;
3018 }
3019
3020 // resource not encapsulated or in package open to caller
3021 String mn = thisModule.getName();
3022 ClassLoader cl = classLoader;
3023 try {
3024 if (cl == null) {
3025 return BootLoader.findResource(mn, name);
3026 } else {
3027 return cl.findResource(mn, name);
3028 }
3029 } catch (IOException ioe) {
3030 return null;
3031 }
3032 }
3033
3034 // unnamed module
3035 ClassLoader cl = classLoader;
3036 if (cl == null) {
3037 return ClassLoader.getSystemResource(name);
3038 } else {
3039 return cl.getResource(name);
3040 }
3041 }
3042
3043 /**
3044 * Returns true if a resource with the given name can be located by the
3045 * given caller. All resources in a module can be located by code in
3046 * the module. For other callers, then the package needs to be open to
3047 * the caller.
3048 */
3049 private boolean isOpenToCaller(String name, Class<?> caller) {
3050 // assert getModule().isNamed();
3051 Module thisModule = getModule();
3052 Module callerModule = (caller != null) ? caller.getModule() : null;
3053 if (callerModule != thisModule) {
3054 String pn = Resources.toPackageName(name);
3055 if (thisModule.getDescriptor().packages().contains(pn)) {
3056 if (callerModule == null) {
3057 // no caller, return true if the package is open to all modules
3058 return thisModule.isOpen(pn);
3059 }
3060 if (!thisModule.isOpen(pn, callerModule)) {
3061 // package not open to caller
3062 return false;
3063 }
3064 }
3065 }
3066 return true;
3067 }
3068
3069
3070 /** protection domain returned when the internal domain is null */
3071 private static java.security.ProtectionDomain allPermDomain;
3072
3073 /**
3074 * Returns the {@code ProtectionDomain} of this class. If there is a
3075 * security manager installed, this method first calls the security
3076 * manager's {@code checkPermission} method with a
3077 * {@code RuntimePermission("getProtectionDomain")} permission to
3078 * ensure it's ok to get the
3079 * {@code ProtectionDomain}.
3080 *
3081 * @return the ProtectionDomain of this class
3082 *
3083 * @throws SecurityException
3084 * if a security manager exists and its
3085 * {@code checkPermission} method doesn't allow
3086 * getting the ProtectionDomain.
3087 *
3088 * @see java.security.ProtectionDomain
3089 * @see SecurityManager#checkPermission
3090 * @see java.lang.RuntimePermission
3091 * @since 1.2
3092 */
3093 public java.security.ProtectionDomain getProtectionDomain() {
3094 @SuppressWarnings("removal")
3095 SecurityManager sm = System.getSecurityManager();
3096 if (sm != null) {
3097 sm.checkPermission(SecurityConstants.GET_PD_PERMISSION);
3098 }
3099 return protectionDomain();
3100 }
3101
3102 // package-private
3103 java.security.ProtectionDomain protectionDomain() {
3104 java.security.ProtectionDomain pd = getProtectionDomain0();
3105 if (pd == null) {
3106 if (allPermDomain == null) {
3107 java.security.Permissions perms =
3108 new java.security.Permissions();
3109 perms.add(SecurityConstants.ALL_PERMISSION);
3110 allPermDomain =
3111 new java.security.ProtectionDomain(null, perms);
3112 }
3113 pd = allPermDomain;
3114 }
3115 return pd;
3116 }
3117
3118 /**
3119 * Returns the ProtectionDomain of this class.
3120 */
3121 private native java.security.ProtectionDomain getProtectionDomain0();
3122
3123 /*
3124 * Return the Virtual Machine's Class object for the named
3125 * primitive type.
3126 */
3127 static native Class<?> getPrimitiveClass(String name);
3128
3129 /*
3130 * Check if client is allowed to access members. If access is denied,
3131 * throw a SecurityException.
3132 *
3133 * This method also enforces package access.
3134 *
3135 * <p> Default policy: allow all clients access with normal Java access
3136 * control.
3137 *
3138 * <p> NOTE: should only be called if a SecurityManager is installed
3139 */
3140 private void checkMemberAccess(@SuppressWarnings("removal") SecurityManager sm, int which,
3141 Class<?> caller, boolean checkProxyInterfaces) {
3142 /* Default policy allows access to all {@link Member#PUBLIC} members,
3143 * as well as access to classes that have the same class loader as the caller.
3144 * In all other cases, it requires RuntimePermission("accessDeclaredMembers")
3145 * permission.
3146 */
3147 final ClassLoader ccl = ClassLoader.getClassLoader(caller);
3148 if (which != Member.PUBLIC) {
3149 final ClassLoader cl = classLoader;
3150 if (ccl != cl) {
3151 sm.checkPermission(SecurityConstants.CHECK_MEMBER_ACCESS_PERMISSION);
3152 }
3153 }
3154 this.checkPackageAccess(sm, ccl, checkProxyInterfaces);
3155 }
3156
3157 /*
3158 * Checks if a client loaded in ClassLoader ccl is allowed to access this
3159 * class under the current package access policy. If access is denied,
3160 * throw a SecurityException.
3161 *
3162 * NOTE: this method should only be called if a SecurityManager is active
3163 */
3164 private void checkPackageAccess(@SuppressWarnings("removal") SecurityManager sm, final ClassLoader ccl,
3165 boolean checkProxyInterfaces) {
3166 final ClassLoader cl = classLoader;
3167
3168 if (ReflectUtil.needsPackageAccessCheck(ccl, cl)) {
3169 String pkg = this.getPackageName();
3170 if (!pkg.isEmpty()) {
3171 // skip the package access check on a proxy class in default proxy package
3172 if (!Proxy.isProxyClass(this) || ReflectUtil.isNonPublicProxyClass(this)) {
3173 sm.checkPackageAccess(pkg);
3174 }
3175 }
3176 }
3177 // check package access on the proxy interfaces
3178 if (checkProxyInterfaces && Proxy.isProxyClass(this)) {
3179 ReflectUtil.checkProxyPackageAccess(ccl, this.getInterfaces(/* cloneArray */ false));
3180 }
3181 }
3182
3183 /*
3184 * Checks if a client loaded in ClassLoader ccl is allowed to access the provided
3185 * classes under the current package access policy. If access is denied,
3186 * throw a SecurityException.
3187 *
3188 * NOTE: this method should only be called if a SecurityManager is active
3189 * classes must be non-empty
3190 * all classes provided must be loaded by the same ClassLoader
3191 * NOTE: this method does not support Proxy classes
3192 */
3193 private static void checkPackageAccessForPermittedSubclasses(@SuppressWarnings("removal") SecurityManager sm,
3194 final ClassLoader ccl, Class<?>[] subClasses) {
3195 final ClassLoader cl = subClasses[0].classLoader;
3196
3197 if (ReflectUtil.needsPackageAccessCheck(ccl, cl)) {
3198 Set<String> packages = new HashSet<>();
3199
3200 for (Class<?> c : subClasses) {
3201 if (Proxy.isProxyClass(c))
3202 throw new InternalError("a permitted subclass should not be a proxy class: " + c);
3203 String pkg = c.getPackageName();
3204 if (!pkg.isEmpty()) {
3205 packages.add(pkg);
3206 }
3207 }
3208 for (String pkg : packages) {
3209 sm.checkPackageAccess(pkg);
3210 }
3211 }
3212 }
3213
3214 /**
3215 * Add a package name prefix if the name is not absolute. Remove leading "/"
3216 * if name is absolute
3217 */
3218 private String resolveName(String name) {
3219 if (!name.startsWith("/")) {
3220 String baseName = getPackageName();
3221 if (!baseName.isEmpty()) {
3222 int len = baseName.length() + 1 + name.length();
3223 StringBuilder sb = new StringBuilder(len);
3224 name = sb.append(baseName.replace('.', '/'))
3225 .append('/')
3226 .append(name)
3227 .toString();
3228 }
3229 } else {
3230 name = name.substring(1);
3231 }
3232 return name;
3233 }
3234
3235 /**
3236 * Atomic operations support.
3237 */
3238 private static class Atomic {
3239 // initialize Unsafe machinery here, since we need to call Class.class instance method
3240 // and have to avoid calling it in the static initializer of the Class class...
3241 private static final Unsafe unsafe = Unsafe.getUnsafe();
3242 // offset of Class.reflectionData instance field
3243 private static final long reflectionDataOffset
3244 = unsafe.objectFieldOffset(Class.class, "reflectionData");
3245 // offset of Class.annotationType instance field
3246 private static final long annotationTypeOffset
3247 = unsafe.objectFieldOffset(Class.class, "annotationType");
3248 // offset of Class.annotationData instance field
3249 private static final long annotationDataOffset
3250 = unsafe.objectFieldOffset(Class.class, "annotationData");
3251
3252 static <T> boolean casReflectionData(Class<?> clazz,
3253 SoftReference<ReflectionData<T>> oldData,
3254 SoftReference<ReflectionData<T>> newData) {
3255 return unsafe.compareAndSetReference(clazz, reflectionDataOffset, oldData, newData);
3256 }
3257
3258 static boolean casAnnotationType(Class<?> clazz,
3259 AnnotationType oldType,
3260 AnnotationType newType) {
3261 return unsafe.compareAndSetReference(clazz, annotationTypeOffset, oldType, newType);
3262 }
3263
3264 static boolean casAnnotationData(Class<?> clazz,
3265 AnnotationData oldData,
3266 AnnotationData newData) {
3267 return unsafe.compareAndSetReference(clazz, annotationDataOffset, oldData, newData);
3268 }
3269 }
3270
3271 /**
3272 * Reflection support.
3273 */
3274
3275 // Reflection data caches various derived names and reflective members. Cached
3276 // values may be invalidated when JVM TI RedefineClasses() is called
3277 private static class ReflectionData<T> {
3278 volatile Field[] declaredFields;
3279 volatile Field[] publicFields;
3280 volatile Method[] declaredMethods;
3281 volatile Method[] publicMethods;
3282 volatile Constructor<T>[] declaredConstructors;
3283 volatile Constructor<T>[] publicConstructors;
3284 // Intermediate results for getFields and getMethods
3285 volatile Field[] declaredPublicFields;
3286 volatile Method[] declaredPublicMethods;
3287 volatile Class<?>[] interfaces;
3288
3289 // Cached names
3290 String simpleName;
3291 String canonicalName;
3292 static final String NULL_SENTINEL = new String();
3293
3294 // Value of classRedefinedCount when we created this ReflectionData instance
3295 final int redefinedCount;
3296
3297 ReflectionData(int redefinedCount) {
3298 this.redefinedCount = redefinedCount;
3299 }
3300 }
3301
3302 private transient volatile SoftReference<ReflectionData<T>> reflectionData;
3303
3304 // Incremented by the VM on each call to JVM TI RedefineClasses()
3305 // that redefines this class or a superclass.
3306 private transient volatile int classRedefinedCount;
3307
3308 // Lazily create and cache ReflectionData
3309 private ReflectionData<T> reflectionData() {
3310 SoftReference<ReflectionData<T>> reflectionData = this.reflectionData;
3311 int classRedefinedCount = this.classRedefinedCount;
3312 ReflectionData<T> rd;
3313 if (reflectionData != null &&
3314 (rd = reflectionData.get()) != null &&
3315 rd.redefinedCount == classRedefinedCount) {
3316 return rd;
3317 }
3318 // else no SoftReference or cleared SoftReference or stale ReflectionData
3319 // -> create and replace new instance
3320 return newReflectionData(reflectionData, classRedefinedCount);
3321 }
3322
3323 private ReflectionData<T> newReflectionData(SoftReference<ReflectionData<T>> oldReflectionData,
3324 int classRedefinedCount) {
3325 while (true) {
3326 ReflectionData<T> rd = new ReflectionData<>(classRedefinedCount);
3327 // try to CAS it...
3328 if (Atomic.casReflectionData(this, oldReflectionData, new SoftReference<>(rd))) {
3329 return rd;
3330 }
3331 // else retry
3332 oldReflectionData = this.reflectionData;
3333 classRedefinedCount = this.classRedefinedCount;
3334 if (oldReflectionData != null &&
3335 (rd = oldReflectionData.get()) != null &&
3336 rd.redefinedCount == classRedefinedCount) {
3337 return rd;
3338 }
3339 }
3340 }
3341
3342 // Generic signature handling
3343 private native String getGenericSignature0();
3344
3345 // Generic info repository; lazily initialized
3346 private transient volatile ClassRepository genericInfo;
3347
3348 // accessor for factory
3349 private GenericsFactory getFactory() {
3350 // create scope and factory
3351 return CoreReflectionFactory.make(this, ClassScope.make(this));
3352 }
3353
3354 // accessor for generic info repository;
3355 // generic info is lazily initialized
3356 private ClassRepository getGenericInfo() {
3357 ClassRepository genericInfo = this.genericInfo;
3358 if (genericInfo == null) {
3359 String signature = getGenericSignature0();
3360 if (signature == null) {
3361 genericInfo = ClassRepository.NONE;
3362 } else {
3363 genericInfo = ClassRepository.make(signature, getFactory());
3364 }
3365 this.genericInfo = genericInfo;
3366 }
3367 return (genericInfo != ClassRepository.NONE) ? genericInfo : null;
3368 }
3369
3370 // Annotations handling
3371 native byte[] getRawAnnotations();
3372 // Since 1.8
3373 native byte[] getRawTypeAnnotations();
3374 static byte[] getExecutableTypeAnnotationBytes(Executable ex) {
3375 return getReflectionFactory().getExecutableTypeAnnotationBytes(ex);
3376 }
3377
3378 native ConstantPool getConstantPool();
3379
3380 //
3381 //
3382 // java.lang.reflect.Field handling
3383 //
3384 //
3385
3386 // Returns an array of "root" fields. These Field objects must NOT
3387 // be propagated to the outside world, but must instead be copied
3388 // via ReflectionFactory.copyField.
3389 private Field[] privateGetDeclaredFields(boolean publicOnly) {
3390 Field[] res;
3391 ReflectionData<T> rd = reflectionData();
3392 if (rd != null) {
3393 res = publicOnly ? rd.declaredPublicFields : rd.declaredFields;
3394 if (res != null) return res;
3395 }
3396 // No cached value available; request value from VM
3397 res = Reflection.filterFields(this, getDeclaredFields0(publicOnly));
3398 if (rd != null) {
3399 if (publicOnly) {
3400 rd.declaredPublicFields = res;
3401 } else {
3402 rd.declaredFields = res;
3403 }
3404 }
3405 return res;
3406 }
3407
3408 // Returns an array of "root" fields. These Field objects must NOT
3409 // be propagated to the outside world, but must instead be copied
3410 // via ReflectionFactory.copyField.
3411 private Field[] privateGetPublicFields() {
3412 Field[] res;
3413 ReflectionData<T> rd = reflectionData();
3414 if (rd != null) {
3415 res = rd.publicFields;
3416 if (res != null) return res;
3417 }
3418
3419 // Use a linked hash set to ensure order is preserved and
3420 // fields from common super interfaces are not duplicated
3421 LinkedHashSet<Field> fields = new LinkedHashSet<>();
3422
3423 // Local fields
3424 addAll(fields, privateGetDeclaredFields(true));
3425
3426 // Direct superinterfaces, recursively
3427 for (Class<?> si : getInterfaces(/* cloneArray */ false)) {
3428 addAll(fields, si.privateGetPublicFields());
3429 }
3430
3431 // Direct superclass, recursively
3432 Class<?> sc = getSuperclass();
3433 if (sc != null) {
3434 addAll(fields, sc.privateGetPublicFields());
3435 }
3436
3437 res = fields.toArray(new Field[0]);
3438 if (rd != null) {
3439 rd.publicFields = res;
3440 }
3441 return res;
3442 }
3443
3444 private static void addAll(Collection<Field> c, Field[] o) {
3445 for (Field f : o) {
3446 c.add(f);
3447 }
3448 }
3449
3450
3451 //
3452 //
3453 // java.lang.reflect.Constructor handling
3454 //
3455 //
3456
3457 // Returns an array of "root" constructors. These Constructor
3458 // objects must NOT be propagated to the outside world, but must
3459 // instead be copied via ReflectionFactory.copyConstructor.
3460 private Constructor<T>[] privateGetDeclaredConstructors(boolean publicOnly) {
3461 Constructor<T>[] res;
3462 ReflectionData<T> rd = reflectionData();
3463 if (rd != null) {
3464 res = publicOnly ? rd.publicConstructors : rd.declaredConstructors;
3465 if (res != null) return res;
3466 }
3467 // No cached value available; request value from VM
3468 if (isInterface()) {
3469 @SuppressWarnings("unchecked")
3470 Constructor<T>[] temporaryRes = (Constructor<T>[]) new Constructor<?>[0];
3471 res = temporaryRes;
3472 } else {
3473 res = getDeclaredConstructors0(publicOnly);
3474 }
3475 if (rd != null) {
3476 if (publicOnly) {
3477 rd.publicConstructors = res;
3478 } else {
3479 rd.declaredConstructors = res;
3480 }
3481 }
3482 return res;
3483 }
3484
3485 //
3486 //
3487 // java.lang.reflect.Method handling
3488 //
3489 //
3490
3491 // Returns an array of "root" methods. These Method objects must NOT
3492 // be propagated to the outside world, but must instead be copied
3493 // via ReflectionFactory.copyMethod.
3494 private Method[] privateGetDeclaredMethods(boolean publicOnly) {
3495 Method[] res;
3496 ReflectionData<T> rd = reflectionData();
3497 if (rd != null) {
3498 res = publicOnly ? rd.declaredPublicMethods : rd.declaredMethods;
3499 if (res != null) return res;
3500 }
3501 // No cached value available; request value from VM
3502 res = Reflection.filterMethods(this, getDeclaredMethods0(publicOnly));
3503 if (rd != null) {
3504 if (publicOnly) {
3505 rd.declaredPublicMethods = res;
3506 } else {
3507 rd.declaredMethods = res;
3508 }
3509 }
3510 return res;
3511 }
3512
3513 // Returns an array of "root" methods. These Method objects must NOT
3514 // be propagated to the outside world, but must instead be copied
3515 // via ReflectionFactory.copyMethod.
3516 private Method[] privateGetPublicMethods() {
3517 Method[] res;
3518 ReflectionData<T> rd = reflectionData();
3519 if (rd != null) {
3520 res = rd.publicMethods;
3521 if (res != null) return res;
3522 }
3523
3524 // No cached value available; compute value recursively.
3525 // Start by fetching public declared methods...
3526 PublicMethods pms = new PublicMethods();
3527 for (Method m : privateGetDeclaredMethods(/* publicOnly */ true)) {
3528 pms.merge(m);
3529 }
3530 // ...then recur over superclass methods...
3531 Class<?> sc = getSuperclass();
3532 if (sc != null) {
3533 for (Method m : sc.privateGetPublicMethods()) {
3534 pms.merge(m);
3535 }
3536 }
3537 // ...and finally over direct superinterfaces.
3538 for (Class<?> intf : getInterfaces(/* cloneArray */ false)) {
3539 for (Method m : intf.privateGetPublicMethods()) {
3540 // static interface methods are not inherited
3541 if (!Modifier.isStatic(m.getModifiers())) {
3542 pms.merge(m);
3543 }
3544 }
3545 }
3546
3547 res = pms.toArray();
3548 if (rd != null) {
3549 rd.publicMethods = res;
3550 }
3551 return res;
3552 }
3553
3554
3555 //
3556 // Helpers for fetchers of one field, method, or constructor
3557 //
3558
3559 // This method does not copy the returned Field object!
3560 private static Field searchFields(Field[] fields, String name) {
3561 for (Field field : fields) {
3562 if (field.getName().equals(name)) {
3563 return field;
3564 }
3565 }
3566 return null;
3567 }
3568
3569 // Returns a "root" Field object. This Field object must NOT
3570 // be propagated to the outside world, but must instead be copied
3571 // via ReflectionFactory.copyField.
3572 private Field getField0(String name) {
3573 // Note: the intent is that the search algorithm this routine
3574 // uses be equivalent to the ordering imposed by
3575 // privateGetPublicFields(). It fetches only the declared
3576 // public fields for each class, however, to reduce the number
3577 // of Field objects which have to be created for the common
3578 // case where the field being requested is declared in the
3579 // class which is being queried.
3580 Field res;
3581 // Search declared public fields
3582 if ((res = searchFields(privateGetDeclaredFields(true), name)) != null) {
3583 return res;
3584 }
3585 // Direct superinterfaces, recursively
3586 Class<?>[] interfaces = getInterfaces(/* cloneArray */ false);
3587 for (Class<?> c : interfaces) {
3588 if ((res = c.getField0(name)) != null) {
3589 return res;
3590 }
3591 }
3592 // Direct superclass, recursively
3593 if (!isInterface()) {
3594 Class<?> c = getSuperclass();
3595 if (c != null) {
3596 if ((res = c.getField0(name)) != null) {
3597 return res;
3598 }
3599 }
3600 }
3601 return null;
3602 }
3603
3604 // This method does not copy the returned Method object!
3605 private static Method searchMethods(Method[] methods,
3606 String name,
3607 Class<?>[] parameterTypes)
3608 {
3609 ReflectionFactory fact = getReflectionFactory();
3610 Method res = null;
3611 for (Method m : methods) {
3612 if (m.getName().equals(name)
3613 && arrayContentsEq(parameterTypes,
3614 fact.getExecutableSharedParameterTypes(m))
3615 && (res == null
3616 || (res.getReturnType() != m.getReturnType()
3617 && res.getReturnType().isAssignableFrom(m.getReturnType()))))
3618 res = m;
3619 }
3620 return res;
3621 }
3622
3623 private static final Class<?>[] EMPTY_CLASS_ARRAY = new Class<?>[0];
3624
3625 // Returns a "root" Method object. This Method object must NOT
3626 // be propagated to the outside world, but must instead be copied
3627 // via ReflectionFactory.copyMethod.
3628 private Method getMethod0(String name, Class<?>[] parameterTypes) {
3629 PublicMethods.MethodList res = getMethodsRecursive(
3630 name,
3631 parameterTypes == null ? EMPTY_CLASS_ARRAY : parameterTypes,
3632 /* includeStatic */ true);
3633 return res == null ? null : res.getMostSpecific();
3634 }
3635
3636 // Returns a list of "root" Method objects. These Method objects must NOT
3637 // be propagated to the outside world, but must instead be copied
3638 // via ReflectionFactory.copyMethod.
3639 private PublicMethods.MethodList getMethodsRecursive(String name,
3640 Class<?>[] parameterTypes,
3641 boolean includeStatic) {
3642 // 1st check declared public methods
3643 Method[] methods = privateGetDeclaredMethods(/* publicOnly */ true);
3644 PublicMethods.MethodList res = PublicMethods.MethodList
3645 .filter(methods, name, parameterTypes, includeStatic);
3646 // if there is at least one match among declared methods, we need not
3647 // search any further as such match surely overrides matching methods
3648 // declared in superclass(es) or interface(s).
3649 if (res != null) {
3650 return res;
3651 }
3652
3653 // if there was no match among declared methods,
3654 // we must consult the superclass (if any) recursively...
3655 Class<?> sc = getSuperclass();
3656 if (sc != null) {
3657 res = sc.getMethodsRecursive(name, parameterTypes, includeStatic);
3658 }
3659
3660 // ...and coalesce the superclass methods with methods obtained
3661 // from directly implemented interfaces excluding static methods...
3662 for (Class<?> intf : getInterfaces(/* cloneArray */ false)) {
3663 res = PublicMethods.MethodList.merge(
3664 res, intf.getMethodsRecursive(name, parameterTypes,
3665 /* includeStatic */ false));
3666 }
3667
3668 return res;
3669 }
3670
3671 // Returns a "root" Constructor object. This Constructor object must NOT
3672 // be propagated to the outside world, but must instead be copied
3673 // via ReflectionFactory.copyConstructor.
3674 private Constructor<T> getConstructor0(Class<?>[] parameterTypes,
3675 int which) throws NoSuchMethodException
3676 {
3677 ReflectionFactory fact = getReflectionFactory();
3678 Constructor<T>[] constructors = privateGetDeclaredConstructors((which == Member.PUBLIC));
3679 for (Constructor<T> constructor : constructors) {
3680 if (arrayContentsEq(parameterTypes,
3681 fact.getExecutableSharedParameterTypes(constructor))) {
3682 return constructor;
3683 }
3684 }
3685 throw new NoSuchMethodException(methodToString("<init>", parameterTypes));
3686 }
3687
3688 //
3689 // Other helpers and base implementation
3690 //
3691
3692 private static boolean arrayContentsEq(Object[] a1, Object[] a2) {
3693 if (a1 == null) {
3694 return a2 == null || a2.length == 0;
3695 }
3696
3697 if (a2 == null) {
3698 return a1.length == 0;
3699 }
3700
3701 if (a1.length != a2.length) {
3702 return false;
3703 }
3704
3705 for (int i = 0; i < a1.length; i++) {
3706 if (a1[i] != a2[i]) {
3707 return false;
3708 }
3709 }
3710
3711 return true;
3712 }
3713
3714 private static Field[] copyFields(Field[] arg) {
3715 Field[] out = new Field[arg.length];
3716 ReflectionFactory fact = getReflectionFactory();
3717 for (int i = 0; i < arg.length; i++) {
3718 out[i] = fact.copyField(arg[i]);
3719 }
3720 return out;
3721 }
3722
3723 private static Method[] copyMethods(Method[] arg) {
3724 Method[] out = new Method[arg.length];
3725 ReflectionFactory fact = getReflectionFactory();
3726 for (int i = 0; i < arg.length; i++) {
3727 out[i] = fact.copyMethod(arg[i]);
3728 }
3729 return out;
3730 }
3731
3732 private static <U> Constructor<U>[] copyConstructors(Constructor<U>[] arg) {
3733 Constructor<U>[] out = arg.clone();
3734 ReflectionFactory fact = getReflectionFactory();
3735 for (int i = 0; i < out.length; i++) {
3736 out[i] = fact.copyConstructor(out[i]);
3737 }
3738 return out;
3739 }
3740
3741 private native Field[] getDeclaredFields0(boolean publicOnly);
3742 private native Method[] getDeclaredMethods0(boolean publicOnly);
3743 private native Constructor<T>[] getDeclaredConstructors0(boolean publicOnly);
3744 private native Class<?>[] getDeclaredClasses0();
3745
3746 /*
3747 * Returns an array containing the components of the Record attribute,
3748 * or null if the attribute is not present.
3749 *
3750 * Note that this method returns non-null array on a class with
3751 * the Record attribute even if this class is not a record.
3752 */
3753 private native RecordComponent[] getRecordComponents0();
3754 private native boolean isRecord0();
3755
3756 /**
3757 * Helper method to get the method name from arguments.
3758 */
3759 private String methodToString(String name, Class<?>[] argTypes) {
3760 return getName() + '.' + name +
3761 ((argTypes == null || argTypes.length == 0) ?
3762 "()" :
3763 Arrays.stream(argTypes)
3764 .map(c -> c == null ? "null" : c.getName())
3765 .collect(Collectors.joining(",", "(", ")")));
3766 }
3767
3768 /** use serialVersionUID from JDK 1.1 for interoperability */
3769 @java.io.Serial
3770 private static final long serialVersionUID = 3206093459760846163L;
3771
3772
3773 /**
3774 * Class Class is special cased within the Serialization Stream Protocol.
3775 *
3776 * A Class instance is written initially into an ObjectOutputStream in the
3777 * following format:
3778 * <pre>
3779 * {@code TC_CLASS} ClassDescriptor
3780 * A ClassDescriptor is a special cased serialization of
3781 * a {@code java.io.ObjectStreamClass} instance.
3782 * </pre>
3783 * A new handle is generated for the initial time the class descriptor
3784 * is written into the stream. Future references to the class descriptor
3785 * are written as references to the initial class descriptor instance.
3786 *
3787 * @see java.io.ObjectStreamClass
3788 */
3789 @java.io.Serial
3790 private static final ObjectStreamField[] serialPersistentFields =
3791 new ObjectStreamField[0];
3792
3793
3794 /**
3795 * Returns the assertion status that would be assigned to this
3796 * class if it were to be initialized at the time this method is invoked.
3797 * If this class has had its assertion status set, the most recent
3798 * setting will be returned; otherwise, if any package default assertion
3799 * status pertains to this class, the most recent setting for the most
3800 * specific pertinent package default assertion status is returned;
3801 * otherwise, if this class is not a system class (i.e., it has a
3802 * class loader) its class loader's default assertion status is returned;
3803 * otherwise, the system class default assertion status is returned.
3804 *
3805 * @apiNote
3806 * Few programmers will have any need for this method; it is provided
3807 * for the benefit of the JDK itself. (It allows a class to determine at
3808 * the time that it is initialized whether assertions should be enabled.)
3809 * Note that this method is not guaranteed to return the actual
3810 * assertion status that was (or will be) associated with the specified
3811 * class when it was (or will be) initialized.
3812 *
3813 * @return the desired assertion status of the specified class.
3814 * @see java.lang.ClassLoader#setClassAssertionStatus
3815 * @see java.lang.ClassLoader#setPackageAssertionStatus
3816 * @see java.lang.ClassLoader#setDefaultAssertionStatus
3817 * @since 1.4
3818 */
3819 public boolean desiredAssertionStatus() {
3820 ClassLoader loader = classLoader;
3821 // If the loader is null this is a system class, so ask the VM
3822 if (loader == null)
3823 return desiredAssertionStatus0(this);
3824
3825 // If the classloader has been initialized with the assertion
3826 // directives, ask it. Otherwise, ask the VM.
3827 synchronized(loader.assertionLock) {
3828 if (loader.classAssertionStatus != null) {
3829 return loader.desiredAssertionStatus(getName());
3830 }
3831 }
3832 return desiredAssertionStatus0(this);
3833 }
3834
3835 // Retrieves the desired assertion status of this class from the VM
3836 private static native boolean desiredAssertionStatus0(Class<?> clazz);
3837
3838 /**
3839 * Returns true if and only if this class was declared as an enum in the
3840 * source code.
3841 *
3842 * Note that {@link java.lang.Enum} is not itself an enum class.
3843 *
3844 * Also note that if an enum constant is declared with a class body,
3845 * the class of that enum constant object is an anonymous class
3846 * and <em>not</em> the class of the declaring enum class. The
3847 * {@link Enum#getDeclaringClass} method of an enum constant can
3848 * be used to get the class of the enum class declaring the
3849 * constant.
3850 *
3851 * @return true if and only if this class was declared as an enum in the
3852 * source code
3853 * @since 1.5
3854 * @jls 8.9.1 Enum Constants
3855 */
3856 public boolean isEnum() {
3857 // An enum must both directly extend java.lang.Enum and have
3858 // the ENUM bit set; classes for specialized enum constants
3859 // don't do the former.
3860 return (this.getModifiers() & ENUM) != 0 &&
3861 this.getSuperclass() == java.lang.Enum.class;
3862 }
3863
3864 /**
3865 * Returns {@code true} if and only if this class is a record class.
3866 *
3867 * <p> The {@linkplain #getSuperclass() direct superclass} of a record
3868 * class is {@code java.lang.Record}. A record class is {@linkplain
3869 * Modifier#FINAL final}. A record class has (possibly zero) record
3870 * components; {@link #getRecordComponents()} returns a non-null but
3871 * possibly empty value for a record.
3872 *
3873 * <p> Note that class {@link Record} is not a record class and thus
3874 * invoking this method on class {@code Record} returns {@code false}.
3875 *
3876 * @return true if and only if this class is a record class, otherwise false
3877 * @jls 8.10 Record Classes
3878 * @since 16
3879 */
3880 public boolean isRecord() {
3881 // this superclass and final modifier check is not strictly necessary
3882 // they are intrinsified and serve as a fast-path check
3883 return getSuperclass() == java.lang.Record.class &&
3884 (this.getModifiers() & Modifier.FINAL) != 0 &&
3885 isRecord0();
3886 }
3887
3888 // Fetches the factory for reflective objects
3889 @SuppressWarnings("removal")
3890 private static ReflectionFactory getReflectionFactory() {
3891 var factory = reflectionFactory;
3892 if (factory != null) {
3893 return factory;
3894 }
3895 return reflectionFactory =
3896 java.security.AccessController.doPrivileged
3897 (new ReflectionFactory.GetReflectionFactoryAction());
3898 }
3899 private static ReflectionFactory reflectionFactory;
3900
3901 /**
3902 * Returns the elements of this enum class or null if this
3903 * Class object does not represent an enum class.
3904 *
3905 * @return an array containing the values comprising the enum class
3906 * represented by this {@code Class} object in the order they're
3907 * declared, or null if this {@code Class} object does not
3908 * represent an enum class
3909 * @since 1.5
3910 * @jls 8.9.1 Enum Constants
3911 */
3912 public T[] getEnumConstants() {
3913 T[] values = getEnumConstantsShared();
3914 return (values != null) ? values.clone() : null;
3915 }
3916
3917 /**
3918 * Returns the elements of this enum class or null if this
3919 * Class object does not represent an enum class;
3920 * identical to getEnumConstants except that the result is
3921 * uncloned, cached, and shared by all callers.
3922 */
3923 @SuppressWarnings("removal")
3924 T[] getEnumConstantsShared() {
3925 T[] constants = enumConstants;
3926 if (constants == null) {
3927 if (!isEnum()) return null;
3928 try {
3929 final Method values = getMethod("values");
3930 java.security.AccessController.doPrivileged(
3931 new java.security.PrivilegedAction<>() {
3932 public Void run() {
3933 values.setAccessible(true);
3934 return null;
3935 }
3936 });
3937 @SuppressWarnings("unchecked")
3938 T[] temporaryConstants = (T[])values.invoke(null);
3939 enumConstants = constants = temporaryConstants;
3940 }
3941 // These can happen when users concoct enum-like classes
3942 // that don't comply with the enum spec.
3943 catch (InvocationTargetException | NoSuchMethodException |
3944 IllegalAccessException | NullPointerException |
3945 ClassCastException ex) { return null; }
3946 }
3947 return constants;
3948 }
3949 private transient volatile T[] enumConstants;
3950
3951 /**
3952 * Returns a map from simple name to enum constant. This package-private
3953 * method is used internally by Enum to implement
3954 * {@code public static <T extends Enum<T>> T valueOf(Class<T>, String)}
3955 * efficiently. Note that the map is returned by this method is
3956 * created lazily on first use. Typically it won't ever get created.
3957 */
3958 Map<String, T> enumConstantDirectory() {
3959 Map<String, T> directory = enumConstantDirectory;
3960 if (directory == null) {
3961 T[] universe = getEnumConstantsShared();
3962 if (universe == null)
3963 throw new IllegalArgumentException(
3964 getName() + " is not an enum class");
3965 directory = HashMap.newHashMap(universe.length);
3966 for (T constant : universe) {
3967 directory.put(((Enum<?>)constant).name(), constant);
3968 }
3969 enumConstantDirectory = directory;
3970 }
3971 return directory;
3972 }
3973 private transient volatile Map<String, T> enumConstantDirectory;
3974
3975 /**
3976 * Casts an object to the class or interface represented
3977 * by this {@code Class} object.
3978 *
3979 * @param obj the object to be cast
3980 * @return the object after casting, or null if obj is null
3981 *
3982 * @throws ClassCastException if the object is not
3983 * null and is not assignable to the type T.
3984 *
3985 * @since 1.5
3986 */
3987 @SuppressWarnings("unchecked")
3988 @IntrinsicCandidate
3989 public T cast(Object obj) {
3990 if (obj != null && !isInstance(obj))
3991 throw new ClassCastException(cannotCastMsg(obj));
3992 return (T) obj;
3993 }
3994
3995 private String cannotCastMsg(Object obj) {
3996 return "Cannot cast " + obj.getClass().getName() + " to " + getName();
3997 }
3998
3999 /**
4000 * Casts this {@code Class} object to represent a subclass of the class
4001 * represented by the specified class object. Checks that the cast
4002 * is valid, and throws a {@code ClassCastException} if it is not. If
4003 * this method succeeds, it always returns a reference to this {@code Class} object.
4004 *
4005 * <p>This method is useful when a client needs to "narrow" the type of
4006 * a {@code Class} object to pass it to an API that restricts the
4007 * {@code Class} objects that it is willing to accept. A cast would
4008 * generate a compile-time warning, as the correctness of the cast
4009 * could not be checked at runtime (because generic types are implemented
4010 * by erasure).
4011 *
4012 * @param <U> the type to cast this {@code Class} object to
4013 * @param clazz the class of the type to cast this {@code Class} object to
4014 * @return this {@code Class} object, cast to represent a subclass of
4015 * the specified class object.
4016 * @throws ClassCastException if this {@code Class} object does not
4017 * represent a subclass of the specified class (here "subclass" includes
4018 * the class itself).
4019 * @since 1.5
4020 */
4021 @SuppressWarnings("unchecked")
4022 public <U> Class<? extends U> asSubclass(Class<U> clazz) {
4023 if (clazz.isAssignableFrom(this))
4024 return (Class<? extends U>) this;
4025 else
4026 throw new ClassCastException(this.toString());
4027 }
4028
4029 /**
4030 * {@inheritDoc}
4031 * <p>Note that any annotation returned by this method is a
4032 * declaration annotation.
4033 *
4034 * @throws NullPointerException {@inheritDoc}
4035 * @since 1.5
4036 */
4037 @Override
4038 @SuppressWarnings("unchecked")
4039 public <A extends Annotation> A getAnnotation(Class<A> annotationClass) {
4040 Objects.requireNonNull(annotationClass);
4041
4042 return (A) annotationData().annotations.get(annotationClass);
4043 }
4044
4045 /**
4046 * {@inheritDoc}
4047 * @throws NullPointerException {@inheritDoc}
4048 * @since 1.5
4049 */
4050 @Override
4051 public boolean isAnnotationPresent(Class<? extends Annotation> annotationClass) {
4052 return GenericDeclaration.super.isAnnotationPresent(annotationClass);
4053 }
4054
4055 /**
4056 * {@inheritDoc}
4057 * <p>Note that any annotations returned by this method are
4058 * declaration annotations.
4059 *
4060 * @throws NullPointerException {@inheritDoc}
4061 * @since 1.8
4062 */
4063 @Override
4064 public <A extends Annotation> A[] getAnnotationsByType(Class<A> annotationClass) {
4065 Objects.requireNonNull(annotationClass);
4066
4067 AnnotationData annotationData = annotationData();
4068 return AnnotationSupport.getAssociatedAnnotations(annotationData.declaredAnnotations,
4069 this,
4070 annotationClass);
4071 }
4072
4073 /**
4074 * {@inheritDoc}
4075 * <p>Note that any annotations returned by this method are
4076 * declaration annotations.
4077 *
4078 * @since 1.5
4079 */
4080 @Override
4081 public Annotation[] getAnnotations() {
4082 return AnnotationParser.toArray(annotationData().annotations);
4083 }
4084
4085 /**
4086 * {@inheritDoc}
4087 * <p>Note that any annotation returned by this method is a
4088 * declaration annotation.
4089 *
4090 * @throws NullPointerException {@inheritDoc}
4091 * @since 1.8
4092 */
4093 @Override
4094 @SuppressWarnings("unchecked")
4095 public <A extends Annotation> A getDeclaredAnnotation(Class<A> annotationClass) {
4096 Objects.requireNonNull(annotationClass);
4097
4098 return (A) annotationData().declaredAnnotations.get(annotationClass);
4099 }
4100
4101 /**
4102 * {@inheritDoc}
4103 * <p>Note that any annotations returned by this method are
4104 * declaration annotations.
4105 *
4106 * @throws NullPointerException {@inheritDoc}
4107 * @since 1.8
4108 */
4109 @Override
4110 public <A extends Annotation> A[] getDeclaredAnnotationsByType(Class<A> annotationClass) {
4111 Objects.requireNonNull(annotationClass);
4112
4113 return AnnotationSupport.getDirectlyAndIndirectlyPresent(annotationData().declaredAnnotations,
4114 annotationClass);
4115 }
4116
4117 /**
4118 * {@inheritDoc}
4119 * <p>Note that any annotations returned by this method are
4120 * declaration annotations.
4121 *
4122 * @since 1.5
4123 */
4124 @Override
4125 public Annotation[] getDeclaredAnnotations() {
4126 return AnnotationParser.toArray(annotationData().declaredAnnotations);
4127 }
4128
4129 // annotation data that might get invalidated when JVM TI RedefineClasses() is called
4130 private static class AnnotationData {
4131 final Map<Class<? extends Annotation>, Annotation> annotations;
4132 final Map<Class<? extends Annotation>, Annotation> declaredAnnotations;
4133
4134 // Value of classRedefinedCount when we created this AnnotationData instance
4135 final int redefinedCount;
4136
4137 AnnotationData(Map<Class<? extends Annotation>, Annotation> annotations,
4138 Map<Class<? extends Annotation>, Annotation> declaredAnnotations,
4139 int redefinedCount) {
4140 this.annotations = annotations;
4141 this.declaredAnnotations = declaredAnnotations;
4142 this.redefinedCount = redefinedCount;
4143 }
4144 }
4145
4146 // Annotations cache
4147 @SuppressWarnings("UnusedDeclaration")
4148 private transient volatile AnnotationData annotationData;
4149
4150 private AnnotationData annotationData() {
4151 while (true) { // retry loop
4152 AnnotationData annotationData = this.annotationData;
4153 int classRedefinedCount = this.classRedefinedCount;
4154 if (annotationData != null &&
4155 annotationData.redefinedCount == classRedefinedCount) {
4156 return annotationData;
4157 }
4158 // null or stale annotationData -> optimistically create new instance
4159 AnnotationData newAnnotationData = createAnnotationData(classRedefinedCount);
4160 // try to install it
4161 if (Atomic.casAnnotationData(this, annotationData, newAnnotationData)) {
4162 // successfully installed new AnnotationData
4163 return newAnnotationData;
4164 }
4165 }
4166 }
4167
4168 private AnnotationData createAnnotationData(int classRedefinedCount) {
4169 Map<Class<? extends Annotation>, Annotation> declaredAnnotations =
4170 AnnotationParser.parseAnnotations(getRawAnnotations(), getConstantPool(), this);
4171 Class<?> superClass = getSuperclass();
4172 Map<Class<? extends Annotation>, Annotation> annotations = null;
4173 if (superClass != null) {
4174 Map<Class<? extends Annotation>, Annotation> superAnnotations =
4175 superClass.annotationData().annotations;
4176 for (Map.Entry<Class<? extends Annotation>, Annotation> e : superAnnotations.entrySet()) {
4177 Class<? extends Annotation> annotationClass = e.getKey();
4178 if (AnnotationType.getInstance(annotationClass).isInherited()) {
4179 if (annotations == null) { // lazy construction
4180 annotations = LinkedHashMap.newLinkedHashMap(Math.max(
4181 declaredAnnotations.size(),
4182 Math.min(12, declaredAnnotations.size() + superAnnotations.size())
4183 )
4184 );
4185 }
4186 annotations.put(annotationClass, e.getValue());
4187 }
4188 }
4189 }
4190 if (annotations == null) {
4191 // no inherited annotations -> share the Map with declaredAnnotations
4192 annotations = declaredAnnotations;
4193 } else {
4194 // at least one inherited annotation -> declared may override inherited
4195 annotations.putAll(declaredAnnotations);
4196 }
4197 return new AnnotationData(annotations, declaredAnnotations, classRedefinedCount);
4198 }
4199
4200 // Annotation interfaces cache their internal (AnnotationType) form
4201
4202 @SuppressWarnings("UnusedDeclaration")
4203 private transient volatile AnnotationType annotationType;
4204
4205 boolean casAnnotationType(AnnotationType oldType, AnnotationType newType) {
4206 return Atomic.casAnnotationType(this, oldType, newType);
4207 }
4208
4209 AnnotationType getAnnotationType() {
4210 return annotationType;
4211 }
4212
4213 Map<Class<? extends Annotation>, Annotation> getDeclaredAnnotationMap() {
4214 return annotationData().declaredAnnotations;
4215 }
4216
4217 /* Backing store of user-defined values pertaining to this class.
4218 * Maintained by the ClassValue class.
4219 */
4220 transient ClassValue.ClassValueMap classValueMap;
4221
4222 /**
4223 * Returns an {@code AnnotatedType} object that represents the use of a
4224 * type to specify the superclass of the entity represented by this {@code
4225 * Class} object. (The <em>use</em> of type Foo to specify the superclass
4226 * in '... extends Foo' is distinct from the <em>declaration</em> of class
4227 * Foo.)
4228 *
4229 * <p> If this {@code Class} object represents a class whose declaration
4230 * does not explicitly indicate an annotated superclass, then the return
4231 * value is an {@code AnnotatedType} object representing an element with no
4232 * annotations.
4233 *
4234 * <p> If this {@code Class} represents either the {@code Object} class, an
4235 * interface type, an array type, a primitive type, or void, the return
4236 * value is {@code null}.
4237 *
4238 * @return an object representing the superclass
4239 * @since 1.8
4240 */
4241 public AnnotatedType getAnnotatedSuperclass() {
4242 if (this == Object.class ||
4243 isInterface() ||
4244 isArray() ||
4245 isPrimitive() ||
4246 this == Void.TYPE) {
4247 return null;
4248 }
4249
4250 return TypeAnnotationParser.buildAnnotatedSuperclass(getRawTypeAnnotations(), getConstantPool(), this);
4251 }
4252
4253 /**
4254 * Returns an array of {@code AnnotatedType} objects that represent the use
4255 * of types to specify superinterfaces of the entity represented by this
4256 * {@code Class} object. (The <em>use</em> of type Foo to specify a
4257 * superinterface in '... implements Foo' is distinct from the
4258 * <em>declaration</em> of interface Foo.)
4259 *
4260 * <p> If this {@code Class} object represents a class, the return value is
4261 * an array containing objects representing the uses of interface types to
4262 * specify interfaces implemented by the class. The order of the objects in
4263 * the array corresponds to the order of the interface types used in the
4264 * 'implements' clause of the declaration of this {@code Class} object.
4265 *
4266 * <p> If this {@code Class} object represents an interface, the return
4267 * value is an array containing objects representing the uses of interface
4268 * types to specify interfaces directly extended by the interface. The
4269 * order of the objects in the array corresponds to the order of the
4270 * interface types used in the 'extends' clause of the declaration of this
4271 * {@code Class} object.
4272 *
4273 * <p> If this {@code Class} object represents a class or interface whose
4274 * declaration does not explicitly indicate any annotated superinterfaces,
4275 * the return value is an array of length 0.
4276 *
4277 * <p> If this {@code Class} object represents either the {@code Object}
4278 * class, an array type, a primitive type, or void, the return value is an
4279 * array of length 0.
4280 *
4281 * @return an array representing the superinterfaces
4282 * @since 1.8
4283 */
4284 public AnnotatedType[] getAnnotatedInterfaces() {
4285 return TypeAnnotationParser.buildAnnotatedInterfaces(getRawTypeAnnotations(), getConstantPool(), this);
4286 }
4287
4288 private native Class<?> getNestHost0();
4289
4290 /**
4291 * Returns the nest host of the <a href=#nest>nest</a> to which the class
4292 * or interface represented by this {@code Class} object belongs.
4293 * Every class and interface belongs to exactly one nest.
4294 *
4295 * If the nest host of this class or interface has previously
4296 * been determined, then this method returns the nest host.
4297 * If the nest host of this class or interface has
4298 * not previously been determined, then this method determines the nest
4299 * host using the algorithm of JVMS 5.4.4, and returns it.
4300 *
4301 * Often, a class or interface belongs to a nest consisting only of itself,
4302 * in which case this method returns {@code this} to indicate that the class
4303 * or interface is the nest host.
4304 *
4305 * <p>If this {@code Class} object represents a primitive type, an array type,
4306 * or {@code void}, then this method returns {@code this},
4307 * indicating that the represented entity belongs to the nest consisting only of
4308 * itself, and is the nest host.
4309 *
4310 * @return the nest host of this class or interface
4311 *
4312 * @throws SecurityException
4313 * If the returned class is not the current class, and
4314 * if a security manager, <i>s</i>, is present and the caller's
4315 * class loader is not the same as or an ancestor of the class
4316 * loader for the returned class and invocation of {@link
4317 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
4318 * denies access to the package of the returned class
4319 * @since 11
4320 * @jvms 4.7.28 The {@code NestHost} Attribute
4321 * @jvms 4.7.29 The {@code NestMembers} Attribute
4322 * @jvms 5.4.4 Access Control
4323 */
4324 @CallerSensitive
4325 public Class<?> getNestHost() {
4326 if (isPrimitive() || isArray()) {
4327 return this;
4328 }
4329
4330 Class<?> host = getNestHost0();
4331 if (host == this) {
4332 return this;
4333 }
4334 // returning a different class requires a security check
4335 @SuppressWarnings("removal")
4336 SecurityManager sm = System.getSecurityManager();
4337 if (sm != null) {
4338 checkPackageAccess(sm,
4339 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
4340 }
4341 return host;
4342 }
4343
4344 /**
4345 * Determines if the given {@code Class} is a nestmate of the
4346 * class or interface represented by this {@code Class} object.
4347 * Two classes or interfaces are nestmates
4348 * if they have the same {@linkplain #getNestHost() nest host}.
4349 *
4350 * @param c the class to check
4351 * @return {@code true} if this class and {@code c} are members of
4352 * the same nest; and {@code false} otherwise.
4353 *
4354 * @since 11
4355 */
4356 public boolean isNestmateOf(Class<?> c) {
4357 if (this == c) {
4358 return true;
4359 }
4360 if (isPrimitive() || isArray() ||
4361 c.isPrimitive() || c.isArray()) {
4362 return false;
4363 }
4364
4365 return getNestHost() == c.getNestHost();
4366 }
4367
4368 private native Class<?>[] getNestMembers0();
4369
4370 /**
4371 * Returns an array containing {@code Class} objects representing all the
4372 * classes and interfaces that are members of the nest to which the class
4373 * or interface represented by this {@code Class} object belongs.
4374 *
4375 * First, this method obtains the {@linkplain #getNestHost() nest host},
4376 * {@code H}, of the nest to which the class or interface represented by
4377 * this {@code Class} object belongs. The zeroth element of the returned
4378 * array is {@code H}.
4379 *
4380 * Then, for each class or interface {@code C} which is recorded by {@code H}
4381 * as being a member of its nest, this method attempts to obtain the {@code Class}
4382 * object for {@code C} (using {@linkplain #getClassLoader() the defining class
4383 * loader} of the current {@code Class} object), and then obtains the
4384 * {@linkplain #getNestHost() nest host} of the nest to which {@code C} belongs.
4385 * The classes and interfaces which are recorded by {@code H} as being members
4386 * of its nest, and for which {@code H} can be determined as their nest host,
4387 * are indicated by subsequent elements of the returned array. The order of
4388 * such elements is unspecified. Duplicates are permitted.
4389 *
4390 * <p>If this {@code Class} object represents a primitive type, an array type,
4391 * or {@code void}, then this method returns a single-element array containing
4392 * {@code this}.
4393 *
4394 * @apiNote
4395 * The returned array includes only the nest members recorded in the {@code NestMembers}
4396 * attribute, and not any hidden classes that were added to the nest via
4397 * {@link MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
4398 * Lookup::defineHiddenClass}.
4399 *
4400 * @return an array of all classes and interfaces in the same nest as
4401 * this class or interface
4402 *
4403 * @throws SecurityException
4404 * If any returned class is not the current class, and
4405 * if a security manager, <i>s</i>, is present and the caller's
4406 * class loader is not the same as or an ancestor of the class
4407 * loader for that returned class and invocation of {@link
4408 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
4409 * denies access to the package of that returned class
4410 *
4411 * @since 11
4412 * @see #getNestHost()
4413 * @jvms 4.7.28 The {@code NestHost} Attribute
4414 * @jvms 4.7.29 The {@code NestMembers} Attribute
4415 */
4416 @CallerSensitive
4417 public Class<?>[] getNestMembers() {
4418 if (isPrimitive() || isArray()) {
4419 return new Class<?>[] { this };
4420 }
4421 Class<?>[] members = getNestMembers0();
4422 // Can't actually enable this due to bootstrapping issues
4423 // assert(members.length != 1 || members[0] == this); // expected invariant from VM
4424
4425 if (members.length > 1) {
4426 // If we return anything other than the current class we need
4427 // a security check
4428 @SuppressWarnings("removal")
4429 SecurityManager sm = System.getSecurityManager();
4430 if (sm != null) {
4431 checkPackageAccess(sm,
4432 ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
4433 }
4434 }
4435 return members;
4436 }
4437
4438 /**
4439 * Returns the descriptor string of the entity (class, interface, array class,
4440 * primitive type, or {@code void}) represented by this {@code Class} object.
4441 *
4442 * <p> If this {@code Class} object represents a class or interface,
4443 * not an array class, then:
4444 * <ul>
4445 * <li> If the class or interface is not {@linkplain Class#isHidden() hidden},
4446 * then the result is a field descriptor (JVMS {@jvms 4.3.2})
4447 * for the class or interface. Calling
4448 * {@link ClassDesc#ofDescriptor(String) ClassDesc::ofDescriptor}
4449 * with the result descriptor string produces a {@link ClassDesc ClassDesc}
4450 * describing this class or interface.
4451 * <li> If the class or interface is {@linkplain Class#isHidden() hidden},
4452 * then the result is a string of the form:
4453 * <blockquote>
4454 * {@code "L" +} <em>N</em> {@code + "." + <suffix> + ";"}
4455 * </blockquote>
4456 * where <em>N</em> is the <a href="ClassLoader.html#binary-name">binary name</a>
4457 * encoded in internal form indicated by the {@code class} file passed to
4458 * {@link MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
4459 * Lookup::defineHiddenClass}, and {@code <suffix>} is an unqualified name.
4460 * A hidden class or interface has no {@linkplain ClassDesc nominal descriptor}.
4461 * The result string is not a type descriptor.
4462 * </ul>
4463 *
4464 * <p> If this {@code Class} object represents an array class, then
4465 * the result is a string consisting of one or more '{@code [}' characters
4466 * representing the depth of the array nesting, followed by the
4467 * descriptor string of the element type.
4468 * <ul>
4469 * <li> If the element type is not a {@linkplain Class#isHidden() hidden} class
4470 * or interface, then this array class can be described nominally.
4471 * Calling {@link ClassDesc#ofDescriptor(String) ClassDesc::ofDescriptor}
4472 * with the result descriptor string produces a {@link ClassDesc ClassDesc}
4473 * describing this array class.
4474 * <li> If the element type is a {@linkplain Class#isHidden() hidden} class or
4475 * interface, then this array class cannot be described nominally.
4476 * The result string is not a type descriptor.
4477 * </ul>
4478 *
4479 * <p> If this {@code Class} object represents a primitive type or
4480 * {@code void}, then the result is a field descriptor string which
4481 * is a one-letter code corresponding to a primitive type or {@code void}
4482 * ({@code "B", "C", "D", "F", "I", "J", "S", "Z", "V"}) (JVMS {@jvms 4.3.2}).
4483 *
4484 * @apiNote
4485 * This is not a strict inverse of {@link #forName};
4486 * distinct classes which share a common name but have different class loaders
4487 * will have identical descriptor strings.
4488 *
4489 * @return the descriptor string for this {@code Class} object
4490 * @jvms 4.3.2 Field Descriptors
4491 * @since 12
4492 */
4493 @Override
4494 public String descriptorString() {
4495 if (isPrimitive())
4496 return Wrapper.forPrimitiveType(this).basicTypeString();
4497
4498 if (isArray()) {
4499 return "[" + componentType.descriptorString();
4500 } else if (isHidden()) {
4501 String name = getName();
4502 int index = name.indexOf('/');
4503 return new StringBuilder(name.length() + 2)
4504 .append('L')
4505 .append(name.substring(0, index).replace('.', '/'))
4506 .append('.')
4507 .append(name, index + 1, name.length())
4508 .append(';')
4509 .toString();
4510 } else {
4511 String name = getName().replace('.', '/');
4512 return new StringBuilder(name.length() + 2)
4513 .append('L')
4514 .append(name)
4515 .append(';')
4516 .toString();
4517 }
4518 }
4519
4520 /**
4521 * Returns the component type of this {@code Class}, if it describes
4522 * an array type, or {@code null} otherwise.
4523 *
4524 * @implSpec
4525 * Equivalent to {@link Class#getComponentType()}.
4526 *
4527 * @return a {@code Class} describing the component type, or {@code null}
4528 * if this {@code Class} does not describe an array type
4529 * @since 12
4530 */
4531 @Override
4532 public Class<?> componentType() {
4533 return isArray() ? componentType : null;
4534 }
4535
4536 /**
4537 * Returns a {@code Class} for an array type whose component type
4538 * is described by this {@linkplain Class}.
4539 *
4540 * @throws UnsupportedOperationException if this component type is {@linkplain
4541 * Void#TYPE void} or if the number of dimensions of the resulting array
4542 * type would exceed 255.
4543 * @return a {@code Class} describing the array type
4544 * @jvms 4.3.2 Field Descriptors
4545 * @jvms 4.4.1 The {@code CONSTANT_Class_info} Structure
4546 * @since 12
4547 */
4548 @Override
4549 public Class<?> arrayType() {
4550 try {
4551 return Array.newInstance(this, 0).getClass();
4552 } catch (IllegalArgumentException iae) {
4553 throw new UnsupportedOperationException(iae);
4554 }
4555 }
4556
4557 /**
4558 * Returns a nominal descriptor for this instance, if one can be
4559 * constructed, or an empty {@link Optional} if one cannot be.
4560 *
4561 * @return An {@link Optional} containing the resulting nominal descriptor,
4562 * or an empty {@link Optional} if one cannot be constructed.
4563 * @since 12
4564 */
4565 @Override
4566 public Optional<ClassDesc> describeConstable() {
4567 Class<?> c = isArray() ? elementType() : this;
4568 return c.isHidden() ? Optional.empty()
4569 : Optional.of(ClassDesc.ofDescriptor(descriptorString()));
4570 }
4571
4572 /**
4573 * Returns {@code true} if and only if the underlying class is a hidden class.
4574 *
4575 * @return {@code true} if and only if this class is a hidden class.
4576 *
4577 * @since 15
4578 * @see MethodHandles.Lookup#defineHiddenClass
4579 */
4580 @IntrinsicCandidate
4581 public native boolean isHidden();
4582
4583 /**
4584 * Returns an array containing {@code Class} objects representing the
4585 * direct subinterfaces or subclasses permitted to extend or
4586 * implement this class or interface if it is sealed. The order of such elements
4587 * is unspecified. The array is empty if this sealed class or interface has no
4588 * permitted subclass. If this {@code Class} object represents a primitive type,
4589 * {@code void}, an array type, or a class or interface that is not sealed,
4590 * that is {@link #isSealed()} returns {@code false}, then this method returns {@code null}.
4591 * Conversely, if {@link #isSealed()} returns {@code true}, then this method
4592 * returns a non-null value.
4593 *
4594 * For each class or interface {@code C} which is recorded as a permitted
4595 * direct subinterface or subclass of this class or interface,
4596 * this method attempts to obtain the {@code Class}
4597 * object for {@code C} (using {@linkplain #getClassLoader() the defining class
4598 * loader} of the current {@code Class} object).
4599 * The {@code Class} objects which can be obtained and which are direct
4600 * subinterfaces or subclasses of this class or interface,
4601 * are indicated by elements of the returned array. If a {@code Class} object
4602 * cannot be obtained, it is silently ignored, and not included in the result
4603 * array.
4604 *
4605 * @return an array of {@code Class} objects of the permitted subclasses of this class or interface,
4606 * or {@code null} if this class or interface is not sealed.
4607 *
4608 * @throws SecurityException
4609 * If a security manager, <i>s</i>, is present and the caller's
4610 * class loader is not the same as or an ancestor of the class
4611 * loader for that returned class and invocation of {@link
4612 * SecurityManager#checkPackageAccess s.checkPackageAccess()}
4613 * denies access to the package of any class in the returned array.
4614 *
4615 * @jls 8.1 Class Declarations
4616 * @jls 9.1 Interface Declarations
4617 * @since 17
4618 */
4619 @CallerSensitive
4620 public Class<?>[] getPermittedSubclasses() {
4621 Class<?>[] subClasses;
4622 if (isArray() || isPrimitive() || (subClasses = getPermittedSubclasses0()) == null) {
4623 return null;
4624 }
4625 if (subClasses.length > 0) {
4626 if (Arrays.stream(subClasses).anyMatch(c -> !isDirectSubType(c))) {
4627 subClasses = Arrays.stream(subClasses)
4628 .filter(this::isDirectSubType)
4629 .toArray(s -> new Class<?>[s]);
4630 }
4631 }
4632 if (subClasses.length > 0) {
4633 // If we return some classes we need a security check:
4634 @SuppressWarnings("removal")
4635 SecurityManager sm = System.getSecurityManager();
4636 if (sm != null) {
4637 checkPackageAccessForPermittedSubclasses(sm,
4638 ClassLoader.getClassLoader(Reflection.getCallerClass()),
4639 subClasses);
4640 }
4641 }
4642 return subClasses;
4643 }
4644
4645 private boolean isDirectSubType(Class<?> c) {
4646 if (isInterface()) {
4647 for (Class<?> i : c.getInterfaces(/* cloneArray */ false)) {
4648 if (i == this) {
4649 return true;
4650 }
4651 }
4652 } else {
4653 return c.getSuperclass() == this;
4654 }
4655 return false;
4656 }
4657
4658 /**
4659 * Returns {@code true} if and only if this {@code Class} object represents
4660 * a sealed class or interface. If this {@code Class} object represents a
4661 * primitive type, {@code void}, or an array type, this method returns
4662 * {@code false}. A sealed class or interface has (possibly zero) permitted
4663 * subclasses; {@link #getPermittedSubclasses()} returns a non-null but
4664 * possibly empty value for a sealed class or interface.
4665 *
4666 * @return {@code true} if and only if this {@code Class} object represents
4667 * a sealed class or interface.
4668 *
4669 * @jls 8.1 Class Declarations
4670 * @jls 9.1 Interface Declarations
4671 * @since 17
4672 */
4673 public boolean isSealed() {
4674 if (isArray() || isPrimitive()) {
4675 return false;
4676 }
4677 return getPermittedSubclasses() != null;
4678 }
4679
4680 private native Class<?>[] getPermittedSubclasses0();
4681
4682 /*
4683 * Return the class's major and minor class file version packed into an int.
4684 * The high order 16 bits contain the class's minor version. The low order
4685 * 16 bits contain the class's major version.
4686 *
4687 * If the class is an array type then the class file version of its element
4688 * type is returned. If the class is a primitive type then the latest class
4689 * file major version is returned and zero is returned for the minor version.
4690 */
4691 private int getClassFileVersion() {
4692 Class<?> c = isArray() ? elementType() : this;
4693 return c.getClassFileVersion0();
4694 }
4695
4696 private native int getClassFileVersion0();
4697
4698 /*
4699 * Return the access flags as they were in the class's bytecode, including
4700 * the original setting of ACC_SUPER.
4701 *
4702 * If the class is an array type then the access flags of the element type is
4703 * returned. If the class is a primitive then ACC_ABSTRACT | ACC_FINAL | ACC_PUBLIC.
4704 */
4705 private int getClassAccessFlagsRaw() {
4706 Class<?> c = isArray() ? elementType() : this;
4707 return c.getClassAccessFlagsRaw0();
4708 }
4709
4710 private native int getClassAccessFlagsRaw0();
4711 }