1 /*
2 * Copyright (c) 1994, 2025, 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.constant.ConstantDescs;
31 import java.lang.invoke.TypeDescriptor;
32 import java.lang.invoke.MethodHandles;
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.ClassFileFormatVersion;
42 import java.lang.reflect.Constructor;
43 import java.lang.reflect.Executable;
44 import java.lang.reflect.Field;
45 import java.lang.reflect.GenericArrayType;
46 import java.lang.reflect.GenericDeclaration;
47 import java.lang.reflect.InvocationTargetException;
48 import java.lang.reflect.Member;
49 import java.lang.reflect.Method;
50 import java.lang.reflect.Modifier;
51 import java.lang.reflect.Proxy;
52 import java.lang.reflect.RecordComponent;
53 import java.lang.reflect.Type;
54 import java.lang.reflect.TypeVariable;
55 import java.lang.constant.Constable;
56 import java.net.URL;
57 import java.security.AllPermission;
58 import java.security.Permissions;
59 import java.security.ProtectionDomain;
60 import java.util.ArrayList;
61 import java.util.Arrays;
62 import java.util.Collection;
63 import java.util.HashMap;
64 import java.util.LinkedHashMap;
65 import java.util.LinkedHashSet;
66 import java.util.List;
67 import java.util.Map;
68 import java.util.Objects;
69 import java.util.Optional;
70 import java.util.Set;
71 import java.util.stream.Collectors;
72
73 import jdk.internal.constant.ConstantUtils;
74 import jdk.internal.javac.PreviewFeature;
75 import jdk.internal.loader.BootLoader;
76 import jdk.internal.loader.BuiltinClassLoader;
77 import jdk.internal.misc.PreviewFeatures;
78 import jdk.internal.misc.Unsafe;
79 import jdk.internal.module.Resources;
80 import jdk.internal.reflect.CallerSensitive;
81 import jdk.internal.reflect.CallerSensitiveAdapter;
82 import jdk.internal.reflect.ConstantPool;
83 import jdk.internal.reflect.Reflection;
84 import jdk.internal.reflect.ReflectionFactory;
85 import jdk.internal.vm.annotation.IntrinsicCandidate;
86 import jdk.internal.vm.annotation.Stable;
87
88 import sun.invoke.util.Wrapper;
89 import sun.reflect.generics.factory.CoreReflectionFactory;
90 import sun.reflect.generics.factory.GenericsFactory;
91 import sun.reflect.generics.repository.ClassRepository;
92 import sun.reflect.generics.repository.MethodRepository;
93 import sun.reflect.generics.repository.ConstructorRepository;
94 import sun.reflect.generics.scope.ClassScope;
95 import sun.reflect.annotation.*;
96
97 /**
98 * Instances of the class {@code Class} represent classes and
99 * interfaces in a running Java application. An enum class and a record
100 * class are kinds of class; an annotation interface is a kind of
101 * interface. Every array also belongs to a class that is reflected as
102 * a {@code Class} object that is shared by all arrays with the same
103 * element type and number of dimensions. The primitive Java types
104 * ({@code boolean}, {@code byte}, {@code char}, {@code short}, {@code
105 * int}, {@code long}, {@code float}, and {@code double}), and the
106 * keyword {@code void} are also represented as {@code Class} objects.
107 *
108 * <p> {@code Class} has no public constructor. Instead a {@code Class}
109 * object is constructed automatically by the Java Virtual Machine when
110 * a class is derived from the bytes of a {@code class} file through
111 * the invocation of one of the following methods:
112 * <ul>
113 * <li> {@link ClassLoader#defineClass(String, byte[], int, int) ClassLoader::defineClass}
114 * <li> {@link java.lang.invoke.MethodHandles.Lookup#defineClass(byte[])
115 * java.lang.invoke.MethodHandles.Lookup::defineClass}
116 * <li> {@link java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
117 * java.lang.invoke.MethodHandles.Lookup::defineHiddenClass}
118 * </ul>
119 *
120 * <p> The methods of class {@code Class} expose many characteristics of a
121 * class or interface. Most characteristics are derived from the {@code class}
122 * file that the class loader passed to the Java Virtual Machine or
123 * from the {@code class} file passed to {@code Lookup::defineClass}
124 * or {@code Lookup::defineHiddenClass}.
125 * A few characteristics are determined by the class loading environment
126 * at run time, such as the module returned by {@link #getModule() getModule()}.
127 *
128 * <p> The following example uses a {@code Class} object to print the
129 * class name of an object:
130 *
131 * {@snippet lang="java" :
132 * void printClassName(Object obj) {
133 * System.out.println("The class of " + obj +
134 * " is " + obj.getClass().getName());
135 * }}
136 *
137 * It is also possible to get the {@code Class} object for a named
138 * class or interface (or for {@code void}) using a <dfn>class literal</dfn>
139 * (JLS {@jls 15.8.2}).
140 * For example:
141 *
142 * {@snippet lang="java" :
143 * System.out.println("The name of class Foo is: " + Foo.class.getName()); // @highlight substring="Foo.class"
144 * }
145 *
146 * <p> Some methods of class {@code Class} expose whether the declaration of
147 * a class or interface in Java source code was <em>enclosed</em> within
148 * another declaration. Other methods describe how a class or interface
149 * is situated in a <dfn>{@index "nest"}</dfn>. A nest is a set of
150 * classes and interfaces, in the same run-time package, that
151 * allow mutual access to their {@code private} members.
152 * The classes and interfaces are known as <dfn>{@index "nestmates"}</dfn>
153 * (JVMS {@jvms 4.7.29}).
154 * One nestmate acts as the
155 * <dfn>nest host</dfn> (JVMS {@jvms 4.7.28}), and enumerates the other nestmates which
156 * belong to the nest; each of them in turn records it as the nest host.
157 * The classes and interfaces which belong to a nest, including its host, are
158 * determined when
159 * {@code class} files are generated, for example, a Java compiler
160 * will typically record a top-level class as the host of a nest where the
161 * other members are the classes and interfaces whose declarations are
162 * enclosed within the top-level class declaration.
163 *
164 * <h2><a id=hiddenClasses>Hidden Classes</a></h2>
165 * A class or interface created by the invocation of
166 * {@link java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
167 * Lookup::defineHiddenClass} is a {@linkplain Class#isHidden() <dfn>hidden</dfn>}
168 * class or interface.
169 * All kinds of class, including enum classes and record classes, may be
170 * hidden classes; all kinds of interface, including annotation interfaces,
171 * may be hidden interfaces.
172 *
173 * The {@linkplain #getName() name of a hidden class or interface} is
174 * not a {@linkplain ClassLoader##binary-name binary name},
175 * which means the following:
176 * <ul>
177 * <li>A hidden class or interface cannot be referenced by the constant pools
178 * of other classes and interfaces.
179 * <li>A hidden class or interface cannot be described in
180 * {@linkplain java.lang.constant.ConstantDesc <em>nominal form</em>} by
181 * {@link #describeConstable() Class::describeConstable},
182 * {@link ClassDesc#of(String) ClassDesc::of}, or
183 * {@link ClassDesc#ofDescriptor(String) ClassDesc::ofDescriptor}.
184 * <li>A hidden class or interface cannot be discovered by {@link #forName Class::forName}
185 * or {@link ClassLoader#loadClass(String, boolean) ClassLoader::loadClass}.
186 * </ul>
187 *
188 * A hidden class or interface is never an array class, but may be
189 * the element type of an array. In all other respects, the fact that
190 * a class or interface is hidden has no bearing on the characteristics
191 * exposed by the methods of class {@code Class}.
192 *
193 * <h2><a id=implicitClasses>Implicitly Declared Classes</a></h2>
194 *
195 * Conventionally, a Java compiler, starting from a source file for an
196 * implicitly declared class, say {@code HelloWorld.java}, creates a
197 * similarly-named {@code class} file, {@code HelloWorld.class}, where
198 * the class stored in that {@code class} file is named {@code
199 * "HelloWorld"}, matching the base names of the source and {@code
200 * class} files.
201 *
202 * For the {@code Class} object of an implicitly declared class {@code
203 * HelloWorld}, the methods to get the {@linkplain #getName name} and
204 * {@linkplain #getTypeName type name} return results
205 * equal to {@code "HelloWorld"}. The {@linkplain #getSimpleName
206 * simple name} of such an implicitly declared class is {@code "HelloWorld"} and
207 * the {@linkplain #getCanonicalName canonical name} is {@code "HelloWorld"}.
208 *
209 * @param <T> the type of the class modeled by this {@code Class}
210 * object. For example, the type of {@code String.class} is {@code
211 * Class<String>}. Use {@code Class<?>} if the class being modeled is
212 * unknown.
213 *
214 * @see java.lang.ClassLoader#defineClass(byte[], int, int)
215 * @since 1.0
216 */
217 public final class Class<T> implements java.io.Serializable,
218 GenericDeclaration,
219 Type,
220 AnnotatedElement,
221 TypeDescriptor.OfField<Class<?>>,
222 Constable {
223 private static final int ANNOTATION = 0x00002000;
224 private static final int ENUM = 0x00004000;
225 private static final int SYNTHETIC = 0x00001000;
226
227 private static native void registerNatives();
228 static {
229 runtimeSetup();
230 }
231
232 // Called from JVM when loading an AOT cache
233 private static void runtimeSetup() {
234 registerNatives();
235 }
236
237 /*
238 * Private constructor. Only the Java Virtual Machine creates Class objects.
239 * This constructor is not used and prevents the default constructor being
240 * generated.
241 */
242 private Class(ClassLoader loader, Class<?> arrayComponentType, char mods, ProtectionDomain pd, boolean isPrim) {
243 // Initialize final field for classLoader. The initialization value of non-null
244 // prevents future JIT optimizations from assuming this final field is null.
245 // The following assignments are done directly by the VM without calling this constructor.
246 classLoader = loader;
247 componentType = arrayComponentType;
248 modifiers = mods;
249 protectionDomain = pd;
250 primitive = isPrim;
251 }
252
253 /**
254 * Converts the object to a string. The string representation is the
255 * string "class" or "interface", followed by a space, and then by the
256 * name of the class in the format returned by {@code getName}.
257 * If this {@code Class} object represents a primitive type,
258 * this method returns the name of the primitive type. If
259 * this {@code Class} object represents void this method returns
260 * "void". If this {@code Class} object represents an array type,
261 * this method returns "class " followed by {@code getName}.
262 *
263 * @return a string representation of this {@code Class} object.
264 */
265 public String toString() {
266 String kind = isInterface() ? "interface " : isPrimitive() ? "" : "class ";
267 return kind.concat(getName());
268 }
269
270 /**
271 * Returns a string describing this {@code Class}, including
272 * information about modifiers, {@link #isSealed() sealed}/{@code
273 * non-sealed} status, and type parameters.
274 *
275 * The string is formatted as a list of type modifiers, if any,
276 * followed by the kind of type (empty string for primitive types
277 * and {@code class}, {@code enum}, {@code interface},
278 * {@code @interface}, or {@code record} as appropriate), followed
279 * by the type's name, followed by an angle-bracketed
280 * comma-separated list of the type's type parameters, if any,
281 * including informative bounds on the type parameters, if any.
282 *
283 * A space is used to separate modifiers from one another and to
284 * separate any modifiers from the kind of type. The modifiers
285 * occur in canonical order. If there are no type parameters, the
286 * type parameter list is elided.
287 *
288 * For an array type, the string starts with the type name,
289 * followed by an angle-bracketed comma-separated list of the
290 * type's type parameters, if any, followed by a sequence of
291 * {@code []} characters, one set of brackets per dimension of
292 * the array.
293 *
294 * <p>Note that since information about the runtime representation
295 * of a type is being generated, modifiers not present on the
296 * originating source code or illegal on the originating source
297 * code may be present.
298 *
299 * @return a string describing this {@code Class}, including
300 * information about modifiers and type parameters
301 *
302 * @since 1.8
303 */
304 public String toGenericString() {
305 if (isPrimitive()) {
306 return toString();
307 } else {
308 StringBuilder sb = new StringBuilder();
309 Class<?> component = this;
310 int arrayDepth = 0;
311
312 if (isArray()) {
313 do {
314 arrayDepth++;
315 component = component.getComponentType();
316 } while (component.isArray());
317 sb.append(component.getName());
318 } else {
319 // Class modifiers are a superset of interface modifiers
320 int modifiers = getModifiers() & Modifier.classModifiers();
321 // Modifier.toString() below mis-interprets SYNCHRONIZED, STRICT, and VOLATILE bits
322 modifiers &= ~(Modifier.SYNCHRONIZED | Modifier.STRICT | Modifier.VOLATILE);
323 if (modifiers != 0) {
324 sb.append(Modifier.toString(modifiers));
325 sb.append(' ');
326 }
327
328 // A class cannot be strictfp and sealed/non-sealed so
329 // it is sufficient to check for sealed-ness after all
330 // modifiers are printed.
331 addSealingInfo(modifiers, sb);
332
333 if (isAnnotation()) {
334 sb.append('@');
335 }
336 if (isInterface()) { // Note: all annotation interfaces are interfaces
337 sb.append("interface");
338 } else {
339 if (isEnum())
340 sb.append("enum");
341 else {
342 if (isValue()) {
343 sb.append("value ");
344 }
345 if (isRecord())
346 sb.append("record");
347 else
348 sb.append("class");
349 }
350 }
351 sb.append(' ');
352 sb.append(getName());
353 }
354
355 TypeVariable<?>[] typeparms = component.getTypeParameters();
356 if (typeparms.length > 0) {
357 sb.append(Arrays.stream(typeparms)
358 .map(Class::typeVarBounds)
359 .collect(Collectors.joining(",", "<", ">")));
360 }
361
362 if (arrayDepth > 0) sb.append("[]".repeat(arrayDepth));
363
364 return sb.toString();
365 }
366 }
367
368 private void addSealingInfo(int modifiers, StringBuilder sb) {
369 // A class can be final XOR sealed XOR non-sealed.
370 if (Modifier.isFinal(modifiers)) {
371 return; // no-op
372 } else {
373 if (isSealed()) {
374 sb.append("sealed ");
375 return;
376 } else {
377 // Check for sealed ancestor, which implies this class
378 // is non-sealed.
379 if (hasSealedAncestor(this)) {
380 sb.append("non-sealed ");
381 }
382 }
383 }
384 }
385
386 private boolean hasSealedAncestor(Class<?> clazz) {
387 // From JLS 8.1.1.2:
388 // "It is a compile-time error if a class has a sealed direct
389 // superclass or a sealed direct superinterface, and is not
390 // declared final, sealed, or non-sealed either explicitly or
391 // implicitly.
392 // Thus, an effect of the sealed keyword is to force all
393 // direct subclasses to explicitly declare whether they are
394 // final, sealed, or non-sealed. This avoids accidentally
395 // exposing a sealed class hierarchy to unwanted subclassing."
396
397 // Therefore, will just check direct superclass and
398 // superinterfaces.
399 var superclass = clazz.getSuperclass();
400 if (superclass != null && superclass.isSealed()) {
401 return true;
402 }
403 for (var superinterface : clazz.getInterfaces()) {
404 if (superinterface.isSealed()) {
405 return true;
406 }
407 }
408 return false;
409 }
410
411 static String typeVarBounds(TypeVariable<?> typeVar) {
412 Type[] bounds = typeVar.getBounds();
413 if (bounds.length == 1 && bounds[0].equals(Object.class)) {
414 return typeVar.getName();
415 } else {
416 return typeVar.getName() + " extends " +
417 Arrays.stream(bounds)
418 .map(Type::getTypeName)
419 .collect(Collectors.joining(" & "));
420 }
421 }
422
423 /**
424 * Returns the {@code Class} object associated with the class or
425 * interface with the given string name. Invoking this method is
426 * equivalent to:
427 *
428 * {@snippet lang="java" :
429 * Class.forName(className, true, currentLoader)
430 * }
431 *
432 * where {@code currentLoader} denotes the defining class loader of
433 * the current class.
434 *
435 * <p> For example, the following code fragment returns the
436 * runtime {@code Class} object for the class named
437 * {@code java.lang.Thread}:
438 *
439 * {@snippet lang="java" :
440 * Class<?> t = Class.forName("java.lang.Thread");
441 * }
442 * <p>
443 * A call to {@code forName("X")} causes the class named
444 * {@code X} to be initialized.
445 *
446 * <p>
447 * In cases where this method is called from a context where there is no
448 * caller frame on the stack (e.g. when called directly from a JNI
449 * attached thread), the system class loader is used.
450 *
451 * @param className the {@linkplain ClassLoader##binary-name binary name}
452 * of the class or the string representing an array type
453 * @return the {@code Class} object for the class with the
454 * specified name.
455 * @throws LinkageError if the linkage fails
456 * @throws ExceptionInInitializerError if the initialization provoked
457 * by this method fails
458 * @throws ClassNotFoundException if the class cannot be located
459 *
460 * @jls 12.2 Loading of Classes and Interfaces
461 * @jls 12.3 Linking of Classes and Interfaces
462 * @jls 12.4 Initialization of Classes and Interfaces
463 */
464 @CallerSensitive
465 public static Class<?> forName(String className)
466 throws ClassNotFoundException {
467 Class<?> caller = Reflection.getCallerClass();
468 return forName(className, caller);
469 }
470
471 // Caller-sensitive adapter method for reflective invocation
472 @CallerSensitiveAdapter
473 private static Class<?> forName(String className, Class<?> caller)
474 throws ClassNotFoundException {
475 ClassLoader loader = (caller == null) ? ClassLoader.getSystemClassLoader()
476 : ClassLoader.getClassLoader(caller);
477 return forName0(className, true, loader, caller);
478 }
479
480 /**
481 * Returns the {@code Class} object associated with the class or
482 * interface with the given string name, using the given class loader.
483 * Given the {@linkplain ClassLoader##binary-name binary name} for a class or interface,
484 * this method attempts to locate and load the class or interface. The specified
485 * class loader is used to load the class or interface. If the parameter
486 * {@code loader} is {@code null}, the class is loaded through the bootstrap
487 * class loader. The class is initialized only if the
488 * {@code initialize} parameter is {@code true} and if it has
489 * not been initialized earlier.
490 *
491 * <p> This method cannot be used to obtain any of the {@code Class} objects
492 * representing primitive types or void, hidden classes or interfaces,
493 * or array classes whose element type is a hidden class or interface.
494 * If {@code name} denotes a primitive type or void, for example {@code I},
495 * an attempt will be made to locate a user-defined class in the unnamed package
496 * whose name is {@code I} instead.
497 * To obtain a {@code Class} object for a named primitive type
498 * such as {@code int} or {@code long} use {@link
499 * #forPrimitiveName(String)}.
500 *
501 * <p> To obtain the {@code Class} object associated with an array class,
502 * the name consists of one or more {@code '['} representing the depth
503 * of the array nesting, followed by the element type as encoded in
504 * {@linkplain ##nameFormat the table} specified in {@code Class.getName()}.
505 *
506 * <p> Examples:
507 * {@snippet lang="java" :
508 * Class<?> threadClass = Class.forName("java.lang.Thread", false, currentLoader);
509 * Class<?> stringArrayClass = Class.forName("[Ljava.lang.String;", false, currentLoader);
510 * Class<?> intArrayClass = Class.forName("[[[I", false, currentLoader); // Class of int[][][]
511 * Class<?> nestedClass = Class.forName("java.lang.Character$UnicodeBlock", false, currentLoader);
512 * Class<?> fooClass = Class.forName("Foo", true, currentLoader);
513 * }
514 *
515 * <p> A call to {@code getName()} on the {@code Class} object returned
516 * from {@code forName(}<i>N</i>{@code )} returns <i>N</i>.
517 *
518 * <p> A call to {@code forName("[L}<i>N</i>{@code ;")} causes the element type
519 * named <i>N</i> to be loaded but not initialized regardless of the value
520 * of the {@code initialize} parameter.
521 *
522 * @apiNote
523 * This method throws errors related to loading, linking or initializing
524 * as specified in Sections {@jls 12.2}, {@jls 12.3}, and {@jls 12.4} of
525 * <cite>The Java Language Specification</cite>.
526 * In addition, this method does not check whether the requested class
527 * is accessible to its caller.
528 *
529 * @param name the {@linkplain ClassLoader##binary-name binary name}
530 * of the class or the string representing an array class
531 *
532 * @param initialize if {@code true} the class will be initialized
533 * (which implies linking). See Section {@jls
534 * 12.4} of <cite>The Java Language
535 * Specification</cite>.
536 * @param loader class loader from which the class must be loaded
537 * @return class object representing the desired class
538 *
539 * @throws LinkageError if the linkage fails
540 * @throws ExceptionInInitializerError if the initialization provoked
541 * by this method fails
542 * @throws ClassNotFoundException if the class cannot be located by
543 * the specified class loader
544 *
545 * @see java.lang.Class#forName(String)
546 * @see java.lang.ClassLoader
547 *
548 * @jls 12.2 Loading of Classes and Interfaces
549 * @jls 12.3 Linking of Classes and Interfaces
550 * @jls 12.4 Initialization of Classes and Interfaces
551 * @jls 13.1 The Form of a Binary
552 * @since 1.2
553 */
554 public static Class<?> forName(String name, boolean initialize, ClassLoader loader)
555 throws ClassNotFoundException
556 {
557 return forName0(name, initialize, loader, null);
558 }
559
560 /** Called after security check for system loader access checks have been made. */
561 private static native Class<?> forName0(String name, boolean initialize,
562 ClassLoader loader,
563 Class<?> caller)
564 throws ClassNotFoundException;
565
566
567 /**
568 * Returns the {@code Class} with the given {@linkplain ClassLoader##binary-name
569 * binary name} in the given module.
570 *
571 * <p> This method attempts to locate and load the class or interface.
572 * It does not link the class, and does not run the class initializer.
573 * If the class is not found, this method returns {@code null}. </p>
574 *
575 * <p> If the class loader of the given module defines other modules and
576 * the given name is a class defined in a different module, this method
577 * returns {@code null} after the class is loaded. </p>
578 *
579 * <p> This method does not check whether the requested class is
580 * accessible to its caller. </p>
581 *
582 * @apiNote
583 * This method does not support loading of array types, unlike
584 * {@link #forName(String, boolean, ClassLoader)}. The class name must be
585 * a binary name. This method returns {@code null} on failure rather than
586 * throwing a {@link ClassNotFoundException}, as is done by
587 * the {@link #forName(String, boolean, ClassLoader)} method.
588 *
589 * @param module A module
590 * @param name The {@linkplain ClassLoader##binary-name binary name}
591 * of the class
592 * @return {@code Class} object of the given name defined in the given module;
593 * {@code null} if not found.
594 *
595 * @throws NullPointerException if the given module or name is {@code null}
596 *
597 * @throws LinkageError if the linkage fails
598 *
599 * @jls 12.2 Loading of Classes and Interfaces
600 * @jls 12.3 Linking of Classes and Interfaces
601 * @since 9
602 */
603 public static Class<?> forName(Module module, String name) {
604 Objects.requireNonNull(module);
605 Objects.requireNonNull(name);
606
607 ClassLoader cl = module.getClassLoader();
608 if (cl != null) {
609 return cl.loadClass(module, name);
610 } else {
611 return BootLoader.loadClass(module, name);
612 }
613 }
614
615 /**
616 * {@return {@code true} if this {@code Class} object represents an identity class,
617 * otherwise {@code false}}
618 *
619 * <ul>
620 * <li>
621 * If this {@code Class} object represents an array type this method returns {@code true}.
622 * <li>
623 * If this {@code Class} object represents an interface, a primitive type,
624 * or {@code void} this method returns {@code false}.
625 * <li>
626 * For all other {@code Class} objects, this method returns {@code true} if either
627 * preview features are disabled or {@linkplain Modifier#IDENTITY} is set in the
628 * {@linkplain #getModifiers() class modifiers}.
629 * </ul>
630 * @see AccessFlag#IDENTITY
631 * @since Valhalla
632 */
633 @PreviewFeature(feature = PreviewFeature.Feature.VALUE_OBJECTS, reflective=true)
634 public boolean isIdentity() {
635 if (isPrimitive()) {
636 return false;
637 } else if (PreviewFeatures.isEnabled()) {
638 return isArray() || Modifier.isIdentity(modifiers);
639 } else {
640 return !isInterface();
641 }
642 }
643
644 /**
645 * {@return {@code true} if this {@code Class} object represents a value class,
646 * otherwise {@code false}}
647 * <ul>
648 * <li>
649 * If this {@code Class} object represents an array type this method returns {@code false}.
650 * <li>
651 * If this {@code Class} object represents an interface, a primitive type,
652 * or {@code void} this method returns {@code true} only if preview features are enabled.
653 * <li>
654 * For all other {@code Class} objects, this method returns {@code true} only if
655 * preview features are enabled and {@linkplain Modifier#IDENTITY} is not set in the
656 * {@linkplain #getModifiers() class modifiers}.
657 * </ul>
658 * @see AccessFlag#IDENTITY
659 * @since Valhalla
660 */
661 @PreviewFeature(feature = PreviewFeature.Feature.VALUE_OBJECTS, reflective=true)
662 public boolean isValue() {
663 if (!PreviewFeatures.isEnabled()) {
664 return false;
665 }
666 return !isIdentity();
667 }
668
669 /**
670 * {@return the {@code Class} object associated with the
671 * {@linkplain #isPrimitive() primitive type} of the given name}
672 * If the argument is not the name of a primitive type, {@code
673 * null} is returned.
674 *
675 * @param primitiveName the name of the primitive type to find
676 *
677 * @throws NullPointerException if the argument is {@code null}
678 *
679 * @jls 4.2 Primitive Types and Values
680 * @jls 15.8.2 Class Literals
681 * @since 22
682 */
683 public static Class<?> forPrimitiveName(String primitiveName) {
684 return switch(primitiveName) {
685 // Integral types
686 case "int" -> int.class;
687 case "long" -> long.class;
688 case "short" -> short.class;
689 case "char" -> char.class;
690 case "byte" -> byte.class;
691
692 // Floating-point types
693 case "float" -> float.class;
694 case "double" -> double.class;
695
696 // Other types
697 case "boolean" -> boolean.class;
698 case "void" -> void.class;
699
700 default -> null;
701 };
702 }
703
704 /**
705 * Creates a new instance of the class represented by this {@code Class}
706 * object. The class is instantiated as if by a {@code new}
707 * expression with an empty argument list. The class is initialized if it
708 * has not already been initialized.
709 *
710 * @deprecated This method propagates any exception thrown by the
711 * nullary constructor, including a checked exception. Use of
712 * this method effectively bypasses the compile-time exception
713 * checking that would otherwise be performed by the compiler.
714 * The {@link
715 * java.lang.reflect.Constructor#newInstance(java.lang.Object...)
716 * Constructor.newInstance} method avoids this problem by wrapping
717 * any exception thrown by the constructor in a (checked) {@link
718 * java.lang.reflect.InvocationTargetException}.
719 *
720 * <p>The call
721 *
722 * {@snippet lang="java" :
723 * clazz.newInstance()
724 * }
725 *
726 * can be replaced by
727 *
728 * {@snippet lang="java" :
729 * clazz.getDeclaredConstructor().newInstance()
730 * }
731 *
732 * The latter sequence of calls is inferred to be able to throw
733 * the additional exception types {@link
734 * InvocationTargetException} and {@link
735 * NoSuchMethodException}. Both of these exception types are
736 * subclasses of {@link ReflectiveOperationException}.
737 *
738 * @return a newly allocated instance of the class represented by this
739 * object.
740 * @throws IllegalAccessException if the class or its nullary
741 * constructor is not accessible.
742 * @throws InstantiationException
743 * if this {@code Class} represents an abstract class,
744 * an interface, an array class, a primitive type, or void;
745 * or if the class has no nullary constructor;
746 * or if the instantiation fails for some other reason.
747 * @throws ExceptionInInitializerError if the initialization
748 * provoked by this method fails.
749 */
750 @CallerSensitive
751 @Deprecated(since="9")
752 public T newInstance()
753 throws InstantiationException, IllegalAccessException
754 {
755 // Constructor lookup
756 Constructor<T> tmpConstructor = cachedConstructor;
757 if (tmpConstructor == null) {
758 if (this == Class.class) {
759 throw new IllegalAccessException(
760 "Can not call newInstance() on the Class for java.lang.Class"
761 );
762 }
763 try {
764 Class<?>[] empty = {};
765 final Constructor<T> c = getReflectionFactory().copyConstructor(
766 getConstructor0(empty, Member.DECLARED));
767 // Disable accessibility checks on the constructor
768 // access check is done with the true caller
769 c.setAccessible(true);
770 cachedConstructor = tmpConstructor = c;
771 } catch (NoSuchMethodException e) {
772 throw (InstantiationException)
773 new InstantiationException(getName()).initCause(e);
774 }
775 }
776
777 try {
778 Class<?> caller = Reflection.getCallerClass();
779 return getReflectionFactory().newInstance(tmpConstructor, null, caller);
780 } catch (InvocationTargetException e) {
781 Unsafe.getUnsafe().throwException(e.getTargetException());
782 // Not reached
783 return null;
784 }
785 }
786
787 private transient volatile Constructor<T> cachedConstructor;
788
789 /**
790 * Determines if the specified {@code Object} is assignment-compatible
791 * with the object represented by this {@code Class}. This method is
792 * the dynamic equivalent of the Java language {@code instanceof}
793 * operator. The method returns {@code true} if the specified
794 * {@code Object} argument is non-null and can be cast to the
795 * reference type represented by this {@code Class} object without
796 * raising a {@code ClassCastException.} It returns {@code false}
797 * otherwise.
798 *
799 * <p> Specifically, if this {@code Class} object represents a
800 * declared class, this method returns {@code true} if the specified
801 * {@code Object} argument is an instance of the represented class (or
802 * of any of its subclasses); it returns {@code false} otherwise. If
803 * this {@code Class} object represents an array class, this method
804 * returns {@code true} if the specified {@code Object} argument
805 * can be converted to an object of the array class by an identity
806 * conversion or by a widening reference conversion; it returns
807 * {@code false} otherwise. If this {@code Class} object
808 * represents an interface, this method returns {@code true} if the
809 * class or any superclass of the specified {@code Object} argument
810 * implements this interface; it returns {@code false} otherwise. If
811 * this {@code Class} object represents a primitive type, this method
812 * returns {@code false}.
813 *
814 * @param obj the object to check
815 * @return true if {@code obj} is an instance of this class
816 *
817 * @since 1.1
818 */
819 @IntrinsicCandidate
820 public native boolean isInstance(Object obj);
821
822
823 /**
824 * Determines if the class or interface represented by this
825 * {@code Class} object is either the same as, or is a superclass or
826 * superinterface of, the class or interface represented by the specified
827 * {@code Class} parameter. It returns {@code true} if so;
828 * otherwise it returns {@code false}. If this {@code Class}
829 * object represents a primitive type, this method returns
830 * {@code true} if the specified {@code Class} parameter is
831 * exactly this {@code Class} object; otherwise it returns
832 * {@code false}.
833 *
834 * <p> Specifically, this method tests whether the type represented by the
835 * specified {@code Class} parameter can be converted to the type
836 * represented by this {@code Class} object via an identity conversion
837 * or via a widening reference conversion. See <cite>The Java Language
838 * Specification</cite>, sections {@jls 5.1.1} and {@jls 5.1.4},
839 * for details.
840 *
841 * @param cls the {@code Class} object to be checked
842 * @return the {@code boolean} value indicating whether objects of the
843 * type {@code cls} can be assigned to objects of this class
844 * @throws NullPointerException if the specified Class parameter is
845 * null.
846 * @since 1.1
847 */
848 @IntrinsicCandidate
849 public native boolean isAssignableFrom(Class<?> cls);
850
851
852 /**
853 * Determines if this {@code Class} object represents an
854 * interface type.
855 *
856 * @return {@code true} if this {@code Class} object represents an interface;
857 * {@code false} otherwise.
858 */
859 public boolean isInterface() {
860 return Modifier.isInterface(modifiers);
861 }
862
863
864 /**
865 * Determines if this {@code Class} object represents an array class.
866 *
867 * @return {@code true} if this {@code Class} object represents an array class;
868 * {@code false} otherwise.
869 * @since 1.1
870 */
871 public boolean isArray() {
872 return componentType != null;
873 }
874
875
876 /**
877 * Determines if this {@code Class} object represents a primitive
878 * type or void.
879 *
880 * <p> There are nine predefined {@code Class} objects to
881 * represent the eight primitive types and void. These are
882 * created by the Java Virtual Machine, and have the same
883 * {@linkplain #getName() names} as the primitive types that they
884 * represent, namely {@code boolean}, {@code byte}, {@code char},
885 * {@code short}, {@code int}, {@code long}, {@code float}, and
886 * {@code double}.
887 *
888 * <p>No other class objects are considered primitive.
889 *
890 * @apiNote
891 * A {@code Class} object represented by a primitive type can be
892 * accessed via the {@code TYPE} public static final variables
893 * defined in the primitive wrapper classes such as {@link
894 * java.lang.Integer#TYPE Integer.TYPE}. In the Java programming
895 * language, the objects may be referred to by a class literal
896 * expression such as {@code int.class}. The {@code Class} object
897 * for void can be expressed as {@code void.class} or {@link
898 * java.lang.Void#TYPE Void.TYPE}.
899 *
900 * @return true if and only if this class represents a primitive type
901 *
902 * @see java.lang.Boolean#TYPE
903 * @see java.lang.Character#TYPE
904 * @see java.lang.Byte#TYPE
905 * @see java.lang.Short#TYPE
906 * @see java.lang.Integer#TYPE
907 * @see java.lang.Long#TYPE
908 * @see java.lang.Float#TYPE
909 * @see java.lang.Double#TYPE
910 * @see java.lang.Void#TYPE
911 * @since 1.1
912 * @jls 15.8.2 Class Literals
913 */
914 public boolean isPrimitive() {
915 return primitive;
916 }
917
918 /**
919 * Returns true if this {@code Class} object represents an annotation
920 * interface. Note that if this method returns true, {@link #isInterface()}
921 * would also return true, as all annotation interfaces are also interfaces.
922 *
923 * @return {@code true} if this {@code Class} object represents an annotation
924 * interface; {@code false} otherwise
925 * @since 1.5
926 */
927 public boolean isAnnotation() {
928 return (getModifiers() & ANNOTATION) != 0;
929 }
930
931 /**
932 *{@return {@code true} if and only if this class has the synthetic modifier
933 * bit set}
934 *
935 * @jls 13.1 The Form of a Binary
936 * @jvms 4.1 The {@code ClassFile} Structure
937 * @see <a
938 * href="{@docRoot}/java.base/java/lang/reflect/package-summary.html#LanguageJvmModel">Java
939 * programming language and JVM modeling in core reflection</a>
940 * @since 1.5
941 */
942 public boolean isSynthetic() {
943 return (getModifiers() & SYNTHETIC) != 0;
944 }
945
946 /**
947 * Returns the name of the entity (class, interface, array class,
948 * primitive type, or void) represented by this {@code Class} object.
949 *
950 * <p> If this {@code Class} object represents a class or interface,
951 * not an array class, then:
952 * <ul>
953 * <li> If the class or interface is not {@linkplain #isHidden() hidden},
954 * then the {@linkplain ClassLoader##binary-name binary name}
955 * of the class or interface is returned.
956 * <li> If the class or interface is hidden, then the result is a string
957 * of the form: {@code N + '/' + <suffix>}
958 * where {@code N} is the {@linkplain ClassLoader##binary-name binary name}
959 * indicated by the {@code class} file passed to
960 * {@link java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
961 * Lookup::defineHiddenClass}, and {@code <suffix>} is an unqualified name.
962 * </ul>
963 *
964 * <p> If this {@code Class} object represents an array class, then
965 * the result is a string consisting of one or more '{@code [}' characters
966 * representing the depth of the array nesting, followed by the element
967 * type as encoded using the following table:
968 *
969 * <blockquote><table class="striped" id="nameFormat">
970 * <caption style="display:none">Element types and encodings</caption>
971 * <thead>
972 * <tr><th scope="col"> Element Type <th scope="col"> Encoding
973 * </thead>
974 * <tbody style="text-align:left">
975 * <tr><th scope="row"> {@code boolean} <td style="text-align:center"> {@code Z}
976 * <tr><th scope="row"> {@code byte} <td style="text-align:center"> {@code B}
977 * <tr><th scope="row"> {@code char} <td style="text-align:center"> {@code C}
978 * <tr><th scope="row"> class or interface with {@linkplain ClassLoader##binary-name binary name} <i>N</i>
979 * <td style="text-align:center"> {@code L}<em>N</em>{@code ;}
980 * <tr><th scope="row"> {@code double} <td style="text-align:center"> {@code D}
981 * <tr><th scope="row"> {@code float} <td style="text-align:center"> {@code F}
982 * <tr><th scope="row"> {@code int} <td style="text-align:center"> {@code I}
983 * <tr><th scope="row"> {@code long} <td style="text-align:center"> {@code J}
984 * <tr><th scope="row"> {@code short} <td style="text-align:center"> {@code S}
985 * </tbody>
986 * </table></blockquote>
987 *
988 * <p> If this {@code Class} object represents a primitive type or {@code void},
989 * then the result is a string with the same spelling as the Java language
990 * keyword which corresponds to the primitive type or {@code void}.
991 *
992 * <p> Examples:
993 * <blockquote><pre>
994 * String.class.getName()
995 * returns "java.lang.String"
996 * Character.UnicodeBlock.class.getName()
997 * returns "java.lang.Character$UnicodeBlock"
998 * byte.class.getName()
999 * returns "byte"
1000 * (new Object[3]).getClass().getName()
1001 * returns "[Ljava.lang.Object;"
1002 * (new int[3][4][5][6][7][8][9]).getClass().getName()
1003 * returns "[[[[[[[I"
1004 * </pre></blockquote>
1005 *
1006 * @apiNote
1007 * Distinct class objects can have the same name but different class loaders.
1008 *
1009 * @return the name of the class, interface, or other entity
1010 * represented by this {@code Class} object.
1011 * @jls 13.1 The Form of a Binary
1012 */
1013 public String getName() {
1014 String name = this.name;
1015 return name != null ? name : initClassName();
1016 }
1017
1018 // Cache the name to reduce the number of calls into the VM.
1019 // This field would be set by VM itself during initClassName call.
1020 private transient String name;
1021 private native String initClassName();
1022
1023 /**
1024 * Returns the class loader for the class. Some implementations may use
1025 * null to represent the bootstrap class loader. This method will return
1026 * null in such implementations if this class was loaded by the bootstrap
1027 * class loader.
1028 *
1029 * <p>If this {@code Class} object
1030 * represents a primitive type or void, null is returned.
1031 *
1032 * @return the class loader that loaded the class or interface
1033 * represented by this {@code Class} object.
1034 * @see java.lang.ClassLoader
1035 */
1036 public ClassLoader getClassLoader() {
1037 return classLoader;
1038 }
1039
1040 // Package-private to allow ClassLoader access
1041 ClassLoader getClassLoader0() { return classLoader; }
1042
1043 /**
1044 * Returns the module that this class or interface is a member of.
1045 *
1046 * If this class represents an array type then this method returns the
1047 * {@code Module} for the element type. If this class represents a
1048 * primitive type or void, then the {@code Module} object for the
1049 * {@code java.base} module is returned.
1050 *
1051 * If this class is in an unnamed module then the {@linkplain
1052 * ClassLoader#getUnnamedModule() unnamed} {@code Module} of the class
1053 * loader for this class is returned.
1054 *
1055 * @return the module that this class or interface is a member of
1056 *
1057 * @since 9
1058 */
1059 public Module getModule() {
1060 return module;
1061 }
1062
1063 // set by VM
1064 @Stable
1065 private transient Module module;
1066
1067 // Initialized in JVM not by private constructor
1068 // This field is filtered from reflection access, i.e. getDeclaredField
1069 // will throw NoSuchFieldException
1070 private final ClassLoader classLoader;
1071
1072 private transient Object classData; // Set by VM
1073 private transient Object[] signers; // Read by VM, mutable
1074 private final transient char modifiers; // Set by the VM
1075 private final transient boolean primitive; // Set by the VM if the Class is a primitive type.
1076
1077 // package-private
1078 Object getClassData() {
1079 return classData;
1080 }
1081
1082 /**
1083 * Returns an array of {@code TypeVariable} objects that represent the
1084 * type variables declared by the generic declaration represented by this
1085 * {@code GenericDeclaration} object, in declaration order. Returns an
1086 * array of length 0 if the underlying generic declaration declares no type
1087 * variables.
1088 *
1089 * @return an array of {@code TypeVariable} objects that represent
1090 * the type variables declared by this generic declaration
1091 * @throws java.lang.reflect.GenericSignatureFormatError if the generic
1092 * signature of this generic declaration does not conform to
1093 * the format specified in section {@jvms 4.7.9} of
1094 * <cite>The Java Virtual Machine Specification</cite>
1095 * @since 1.5
1096 */
1097 @SuppressWarnings("unchecked")
1098 public TypeVariable<Class<T>>[] getTypeParameters() {
1099 ClassRepository info = getGenericInfo();
1100 if (info != null)
1101 return (TypeVariable<Class<T>>[])info.getTypeParameters();
1102 else
1103 return (TypeVariable<Class<T>>[])new TypeVariable<?>[0];
1104 }
1105
1106
1107 /**
1108 * Returns the {@code Class} representing the direct superclass of the
1109 * entity (class, interface, primitive type or void) represented by
1110 * this {@code Class}. If this {@code Class} represents either the
1111 * {@code Object} class, an interface, a primitive type, or void, then
1112 * null is returned. If this {@code Class} object represents an array class
1113 * then the {@code Class} object representing the {@code Object} class is
1114 * returned.
1115 *
1116 * @return the direct superclass of the class represented by this {@code Class} object
1117 */
1118 @IntrinsicCandidate
1119 public native Class<? super T> getSuperclass();
1120
1121
1122 /**
1123 * Returns the {@code Type} representing the direct superclass of
1124 * the entity (class, interface, primitive type or void) represented by
1125 * this {@code Class} object.
1126 *
1127 * <p>If the superclass is a parameterized type, the {@code Type}
1128 * object returned must accurately reflect the actual type
1129 * arguments used in the source code. The parameterized type
1130 * representing the superclass is created if it had not been
1131 * created before. See the declaration of {@link
1132 * java.lang.reflect.ParameterizedType ParameterizedType} for the
1133 * semantics of the creation process for parameterized types. If
1134 * this {@code Class} object represents either the {@code Object}
1135 * class, an interface, a primitive type, or void, then null is
1136 * returned. If this {@code Class} object represents an array class
1137 * then the {@code Class} object representing the {@code Object} class is
1138 * returned.
1139 *
1140 * @throws java.lang.reflect.GenericSignatureFormatError if the generic
1141 * class signature does not conform to the format specified in
1142 * section {@jvms 4.7.9} of <cite>The Java Virtual
1143 * Machine Specification</cite>
1144 * @throws TypeNotPresentException if the generic superclass
1145 * refers to a non-existent type declaration
1146 * @throws java.lang.reflect.MalformedParameterizedTypeException if the
1147 * generic superclass refers to a parameterized type that cannot be
1148 * instantiated for any reason
1149 * @return the direct superclass of the class represented by this {@code Class} object
1150 * @since 1.5
1151 */
1152 public Type getGenericSuperclass() {
1153 ClassRepository info = getGenericInfo();
1154 if (info == null) {
1155 return getSuperclass();
1156 }
1157
1158 // Historical irregularity:
1159 // Generic signature marks interfaces with superclass = Object
1160 // but this API returns null for interfaces
1161 if (isInterface()) {
1162 return null;
1163 }
1164
1165 return info.getSuperclass();
1166 }
1167
1168 /**
1169 * Gets the package of this class.
1170 *
1171 * <p>If this class represents an array type, a primitive type or void,
1172 * this method returns {@code null}.
1173 *
1174 * @return the package of this class.
1175 */
1176 public Package getPackage() {
1177 if (isPrimitive() || isArray()) {
1178 return null;
1179 }
1180 ClassLoader cl = classLoader;
1181 return cl != null ? cl.definePackage(this)
1182 : BootLoader.definePackage(this);
1183 }
1184
1185 /**
1186 * Returns the fully qualified package name.
1187 *
1188 * <p> If this class is a top level class, then this method returns the fully
1189 * qualified name of the package that the class is a member of, or the
1190 * empty string if the class is in an unnamed package.
1191 *
1192 * <p> If this class is a member class, then this method is equivalent to
1193 * invoking {@code getPackageName()} on the {@linkplain #getEnclosingClass
1194 * enclosing class}.
1195 *
1196 * <p> If this class is a {@linkplain #isLocalClass local class} or an {@linkplain
1197 * #isAnonymousClass() anonymous class}, then this method is equivalent to
1198 * invoking {@code getPackageName()} on the {@linkplain #getDeclaringClass
1199 * declaring class} of the {@linkplain #getEnclosingMethod enclosing method} or
1200 * {@linkplain #getEnclosingConstructor enclosing constructor}.
1201 *
1202 * <p> If this class represents an array type then this method returns the
1203 * package name of the element type. If this class represents a primitive
1204 * type or void then the package name "{@code java.lang}" is returned.
1205 *
1206 * @return the fully qualified package name
1207 *
1208 * @since 9
1209 * @jls 6.7 Fully Qualified Names and Canonical Names
1210 */
1211 public String getPackageName() {
1212 String pn = this.packageName;
1213 if (pn == null) {
1214 Class<?> c = isArray() ? elementType() : this;
1215 if (c.isPrimitive()) {
1216 pn = "java.lang";
1217 } else {
1218 String cn = c.getName();
1219 int dot = cn.lastIndexOf('.');
1220 pn = (dot != -1) ? cn.substring(0, dot).intern() : "";
1221 }
1222 this.packageName = pn;
1223 }
1224 return pn;
1225 }
1226
1227 // cached package name
1228 private transient String packageName;
1229
1230 /**
1231 * Returns the interfaces directly implemented by the class or interface
1232 * represented by this {@code Class} object.
1233 *
1234 * <p>If this {@code Class} object represents a class, the return value is an array
1235 * containing objects representing all interfaces directly implemented by
1236 * the class. The order of the interface objects in the array corresponds
1237 * to the order of the interface names in the {@code implements} clause of
1238 * the declaration of the class represented by this {@code Class} object. For example,
1239 * given the declaration:
1240 * <blockquote>
1241 * {@code class Shimmer implements FloorWax, DessertTopping { ... }}
1242 * </blockquote>
1243 * suppose the value of {@code s} is an instance of
1244 * {@code Shimmer}; the value of the expression:
1245 * <blockquote>
1246 * {@code s.getClass().getInterfaces()[0]}
1247 * </blockquote>
1248 * is the {@code Class} object that represents interface
1249 * {@code FloorWax}; and the value of:
1250 * <blockquote>
1251 * {@code s.getClass().getInterfaces()[1]}
1252 * </blockquote>
1253 * is the {@code Class} object that represents interface
1254 * {@code DessertTopping}.
1255 *
1256 * <p>If this {@code Class} object represents an interface, the array contains objects
1257 * representing all interfaces directly extended by the interface. The
1258 * order of the interface objects in the array corresponds to the order of
1259 * the interface names in the {@code extends} clause of the declaration of
1260 * the interface represented by this {@code Class} object.
1261 *
1262 * <p>If this {@code Class} object represents a class or interface that implements no
1263 * interfaces, the method returns an array of length 0.
1264 *
1265 * <p>If this {@code Class} object represents a primitive type or void, the method
1266 * returns an array of length 0.
1267 *
1268 * <p>If this {@code Class} object represents an array type, the
1269 * interfaces {@code Cloneable} and {@code java.io.Serializable} are
1270 * returned in that order.
1271 *
1272 * @return an array of interfaces directly implemented by this class
1273 */
1274 public Class<?>[] getInterfaces() {
1275 // defensively copy before handing over to user code
1276 return getInterfaces(true);
1277 }
1278
1279 private Class<?>[] getInterfaces(boolean cloneArray) {
1280 ReflectionData<T> rd = reflectionData();
1281 Class<?>[] interfaces = rd.interfaces;
1282 if (interfaces == null) {
1283 interfaces = getInterfaces0();
1284 rd.interfaces = interfaces;
1285 }
1286 // defensively copy if requested
1287 return cloneArray ? interfaces.clone() : interfaces;
1288 }
1289
1290 private native Class<?>[] getInterfaces0();
1291
1292 /**
1293 * Returns the {@code Type}s representing the interfaces
1294 * directly implemented by the class or interface represented by
1295 * this {@code Class} object.
1296 *
1297 * <p>If a superinterface is a parameterized type, the
1298 * {@code Type} object returned for it must accurately reflect
1299 * the actual type arguments used in the source code. The
1300 * parameterized type representing each superinterface is created
1301 * if it had not been created before. See the declaration of
1302 * {@link java.lang.reflect.ParameterizedType ParameterizedType}
1303 * for the semantics of the creation process for parameterized
1304 * types.
1305 *
1306 * <p>If this {@code Class} object represents a class, the return value is an array
1307 * containing objects representing all interfaces directly implemented by
1308 * the class. The order of the interface objects in the array corresponds
1309 * to the order of the interface names in the {@code implements} clause of
1310 * the declaration of the class represented by this {@code Class} object.
1311 *
1312 * <p>If this {@code Class} object represents an interface, the array contains objects
1313 * representing all interfaces directly extended by the interface. The
1314 * order of the interface objects in the array corresponds to the order of
1315 * the interface names in the {@code extends} clause of the declaration of
1316 * the interface represented by this {@code Class} object.
1317 *
1318 * <p>If this {@code Class} object represents a class or interface that implements no
1319 * interfaces, the method returns an array of length 0.
1320 *
1321 * <p>If this {@code Class} object represents a primitive type or void, the method
1322 * returns an array of length 0.
1323 *
1324 * <p>If this {@code Class} object represents an array type, the
1325 * interfaces {@code Cloneable} and {@code java.io.Serializable} are
1326 * returned in that order.
1327 *
1328 * @throws java.lang.reflect.GenericSignatureFormatError
1329 * if the generic class signature does not conform to the
1330 * format specified in section {@jvms 4.7.9} of <cite>The
1331 * Java Virtual Machine Specification</cite>
1332 * @throws TypeNotPresentException if any of the generic
1333 * superinterfaces refers to a non-existent type declaration
1334 * @throws java.lang.reflect.MalformedParameterizedTypeException
1335 * if any of the generic superinterfaces refer to a parameterized
1336 * type that cannot be instantiated for any reason
1337 * @return an array of interfaces directly implemented by this class
1338 * @since 1.5
1339 */
1340 public Type[] getGenericInterfaces() {
1341 ClassRepository info = getGenericInfo();
1342 return (info == null) ? getInterfaces() : info.getSuperInterfaces();
1343 }
1344
1345
1346 /**
1347 * Returns the {@code Class} representing the component type of an
1348 * array. If this class does not represent an array class this method
1349 * returns null.
1350 *
1351 * @return the {@code Class} representing the component type of this
1352 * class if this class is an array
1353 * @see java.lang.reflect.Array
1354 * @since 1.1
1355 */
1356 public Class<?> getComponentType() {
1357 return componentType;
1358 }
1359
1360 // The componentType field's null value is the sole indication that the class
1361 // is an array - see isArray().
1362 private transient final Class<?> componentType;
1363
1364 /*
1365 * Returns the {@code Class} representing the element type of an array class.
1366 * If this class does not represent an array class, then this method returns
1367 * {@code null}.
1368 */
1369 private Class<?> elementType() {
1370 if (!isArray()) return null;
1371
1372 Class<?> c = this;
1373 while (c.isArray()) {
1374 c = c.getComponentType();
1375 }
1376 return c;
1377 }
1378
1379 /**
1380 * Returns the Java language modifiers for this class or interface, encoded
1381 * in an integer. The modifiers consist of the Java Virtual Machine's
1382 * constants for {@code public}, {@code protected},
1383 * {@code private}, {@code final}, {@code static},
1384 * {@code abstract} and {@code interface}; they should be decoded
1385 * using the methods of class {@code Modifier}.
1386 *
1387 * <p> If the underlying class is an array class:
1388 * <ul>
1389 * <li> its {@code public}, {@code private} and {@code protected}
1390 * modifiers are the same as those of its component type
1391 * <li> its {@code abstract} and {@code final} modifiers are always
1392 * {@code true}
1393 * <li> its interface modifier is always {@code false}, even when
1394 * the component type is an interface
1395 * <li> its {@code identity} modifier is always true
1396 * </ul>
1397 * If this {@code Class} object represents a primitive type or
1398 * void, its {@code public}, {@code abstract}, and {@code final}
1399 * modifiers are always {@code true}.
1400 * For {@code Class} objects representing void, primitive types, and
1401 * arrays, the values of other modifiers are {@code false} other
1402 * than as specified above.
1403 *
1404 * <p> The modifier encodings are defined in section {@jvms 4.1}
1405 * of <cite>The Java Virtual Machine Specification</cite>.
1406 *
1407 * @return the {@code int} representing the modifiers for this class
1408 * @see java.lang.reflect.Modifier
1409 * @see #accessFlags()
1410 * @see <a
1411 * href="{@docRoot}/java.base/java/lang/reflect/package-summary.html#LanguageJvmModel">Java
1412 * programming language and JVM modeling in core reflection</a>
1413 * @since 1.1
1414 * @jls 8.1.1 Class Modifiers
1415 * @jls 9.1.1 Interface Modifiers
1416 * @jvms 4.1 The {@code ClassFile} Structure
1417 */
1418 public int getModifiers() { return modifiers; }
1419
1420 /**
1421 * {@return an unmodifiable set of the {@linkplain AccessFlag access
1422 * flags} for this class, possibly empty}
1423 * The {@code AccessFlags} may depend on the class file format version of the class.
1424 *
1425 * <p> If the underlying class is an array class:
1426 * <ul>
1427 * <li> its {@code PUBLIC}, {@code PRIVATE} and {@code PROTECTED}
1428 * access flags are the same as those of its component type
1429 * <li> its {@code ABSTRACT} and {@code FINAL} flags are present
1430 * <li> its {@code INTERFACE} flag is absent, even when the
1431 * component type is an interface
1432 * <li> its {@code identity} modifier is always true
1433 * </ul>
1434 * If this {@code Class} object represents a primitive type or
1435 * void, the flags are {@code PUBLIC}, {@code ABSTRACT}, and
1436 * {@code FINAL}.
1437 * For {@code Class} objects representing void, primitive types, and
1438 * arrays, access flags are absent other than as specified above.
1439 *
1440 * @see #getModifiers()
1441 * @jvms 4.1 The ClassFile Structure
1442 * @jvms 4.7.6 The InnerClasses Attribute
1443 * @since 20
1444 */
1445 public Set<AccessFlag> accessFlags() {
1446 // Location.CLASS allows SUPER and AccessFlag.MODULE which
1447 // INNER_CLASS forbids. INNER_CLASS allows PRIVATE, PROTECTED,
1448 // and STATIC, which are not allowed on Location.CLASS.
1449 // Use getClassAccessFlagsRaw to expose SUPER status.
1450 var location = (isMemberClass() || isLocalClass() ||
1451 isAnonymousClass() || isArray()) ?
1452 AccessFlag.Location.INNER_CLASS :
1453 AccessFlag.Location.CLASS;
1454 int accessFlags = (location == AccessFlag.Location.CLASS) ?
1455 getClassAccessFlagsRaw() : getModifiers();
1456 if (isArray() && PreviewFeatures.isEnabled()) {
1457 accessFlags |= Modifier.IDENTITY;
1458 }
1459 var cffv = ClassFileFormatVersion.fromMajor(getClassFileVersion() & 0xffff);
1460 if (cffv.compareTo(ClassFileFormatVersion.latest()) >= 0) {
1461 // Ignore unspecified (0x0800) access flag for current version
1462 accessFlags &= ~0x0800;
1463 }
1464 return AccessFlag.maskToAccessFlags(accessFlags, location, cffv);
1465 }
1466
1467 /**
1468 * Gets the signers of this class.
1469 *
1470 * @return the signers of this class, or null if there are no signers. In
1471 * particular, this method returns null if this {@code Class} object represents
1472 * a primitive type or void.
1473 * @since 1.1
1474 */
1475
1476 public Object[] getSigners() {
1477 var signers = this.signers;
1478 return signers == null ? null : signers.clone();
1479 }
1480
1481 /**
1482 * Set the signers of this class.
1483 */
1484 void setSigners(Object[] signers) {
1485 if (!isPrimitive() && !isArray()) {
1486 this.signers = signers;
1487 }
1488 }
1489
1490 /**
1491 * If this {@code Class} object represents a local or anonymous
1492 * class within a method, returns a {@link
1493 * java.lang.reflect.Method Method} object representing the
1494 * immediately enclosing method of the underlying class. Returns
1495 * {@code null} otherwise.
1496 *
1497 * In particular, this method returns {@code null} if the underlying
1498 * class is a local or anonymous class immediately enclosed by a class or
1499 * interface declaration, instance initializer or static initializer.
1500 *
1501 * @return the immediately enclosing method of the underlying class, if
1502 * that class is a local or anonymous class; otherwise {@code null}.
1503 *
1504 * @since 1.5
1505 */
1506 public Method getEnclosingMethod() {
1507 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1508
1509 if (enclosingInfo == null)
1510 return null;
1511 else {
1512 if (!enclosingInfo.isMethod())
1513 return null;
1514
1515 MethodRepository typeInfo = MethodRepository.make(enclosingInfo.getDescriptor(),
1516 getFactory());
1517 Class<?> returnType = toClass(typeInfo.getReturnType());
1518 Type [] parameterTypes = typeInfo.getParameterTypes();
1519 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length];
1520
1521 // Convert Types to Classes; returned types *should*
1522 // be class objects since the methodDescriptor's used
1523 // don't have generics information
1524 for(int i = 0; i < parameterClasses.length; i++)
1525 parameterClasses[i] = toClass(parameterTypes[i]);
1526
1527 final Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass();
1528 Method[] candidates = enclosingCandidate.privateGetDeclaredMethods(false);
1529
1530 /*
1531 * Loop over all declared methods; match method name,
1532 * number of and type of parameters, *and* return
1533 * type. Matching return type is also necessary
1534 * because of covariant returns, etc.
1535 */
1536 ReflectionFactory fact = getReflectionFactory();
1537 for (Method m : candidates) {
1538 if (m.getName().equals(enclosingInfo.getName()) &&
1539 arrayContentsEq(parameterClasses,
1540 fact.getExecutableSharedParameterTypes(m))) {
1541 // finally, check return type
1542 if (m.getReturnType().equals(returnType)) {
1543 return fact.copyMethod(m);
1544 }
1545 }
1546 }
1547
1548 throw new InternalError("Enclosing method not found");
1549 }
1550 }
1551
1552 private native Object[] getEnclosingMethod0();
1553
1554 private EnclosingMethodInfo getEnclosingMethodInfo() {
1555 Object[] enclosingInfo = getEnclosingMethod0();
1556 if (enclosingInfo == null)
1557 return null;
1558 else {
1559 return new EnclosingMethodInfo(enclosingInfo);
1560 }
1561 }
1562
1563 private static final class EnclosingMethodInfo {
1564 private final Class<?> enclosingClass;
1565 private final String name;
1566 private final String descriptor;
1567
1568 static void validate(Object[] enclosingInfo) {
1569 if (enclosingInfo.length != 3)
1570 throw new InternalError("Malformed enclosing method information");
1571 try {
1572 // The array is expected to have three elements:
1573
1574 // the immediately enclosing class
1575 Class<?> enclosingClass = (Class<?>)enclosingInfo[0];
1576 assert(enclosingClass != null);
1577
1578 // the immediately enclosing method or constructor's
1579 // name (can be null).
1580 String name = (String)enclosingInfo[1];
1581
1582 // the immediately enclosing method or constructor's
1583 // descriptor (null iff name is).
1584 String descriptor = (String)enclosingInfo[2];
1585 assert((name != null && descriptor != null) || name == descriptor);
1586 } catch (ClassCastException cce) {
1587 throw new InternalError("Invalid type in enclosing method information", cce);
1588 }
1589 }
1590
1591 EnclosingMethodInfo(Object[] enclosingInfo) {
1592 validate(enclosingInfo);
1593 this.enclosingClass = (Class<?>)enclosingInfo[0];
1594 this.name = (String)enclosingInfo[1];
1595 this.descriptor = (String)enclosingInfo[2];
1596 }
1597
1598 boolean isPartial() {
1599 return enclosingClass == null || name == null || descriptor == null;
1600 }
1601
1602 boolean isConstructor() { return !isPartial() && ConstantDescs.INIT_NAME.equals(name); }
1603
1604 boolean isMethod() { return !isPartial() && !isConstructor() && !ConstantDescs.CLASS_INIT_NAME.equals(name); }
1605
1606 Class<?> getEnclosingClass() { return enclosingClass; }
1607
1608 String getName() { return name; }
1609
1610 String getDescriptor() { return descriptor; }
1611
1612 }
1613
1614 private static Class<?> toClass(Type o) {
1615 if (o instanceof GenericArrayType gat)
1616 return toClass(gat.getGenericComponentType()).arrayType();
1617 return (Class<?>)o;
1618 }
1619
1620 /**
1621 * If this {@code Class} object represents a local or anonymous
1622 * class within a constructor, returns a {@link
1623 * java.lang.reflect.Constructor Constructor} object representing
1624 * the immediately enclosing constructor of the underlying
1625 * class. Returns {@code null} otherwise. In particular, this
1626 * method returns {@code null} if the underlying class is a local
1627 * or anonymous class immediately enclosed by a class or
1628 * interface declaration, instance initializer or static initializer.
1629 *
1630 * @return the immediately enclosing constructor of the underlying class, if
1631 * that class is a local or anonymous class; otherwise {@code null}.
1632 *
1633 * @since 1.5
1634 */
1635 public Constructor<?> getEnclosingConstructor() {
1636 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1637
1638 if (enclosingInfo == null)
1639 return null;
1640 else {
1641 if (!enclosingInfo.isConstructor())
1642 return null;
1643
1644 ConstructorRepository typeInfo = ConstructorRepository.make(enclosingInfo.getDescriptor(),
1645 getFactory());
1646 Type [] parameterTypes = typeInfo.getParameterTypes();
1647 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length];
1648
1649 // Convert Types to Classes; returned types *should*
1650 // be class objects since the methodDescriptor's used
1651 // don't have generics information
1652 for (int i = 0; i < parameterClasses.length; i++)
1653 parameterClasses[i] = toClass(parameterTypes[i]);
1654
1655
1656 final Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass();
1657 Constructor<?>[] candidates = enclosingCandidate
1658 .privateGetDeclaredConstructors(false);
1659 /*
1660 * Loop over all declared constructors; match number
1661 * of and type of parameters.
1662 */
1663 ReflectionFactory fact = getReflectionFactory();
1664 for (Constructor<?> c : candidates) {
1665 if (arrayContentsEq(parameterClasses,
1666 fact.getExecutableSharedParameterTypes(c))) {
1667 return fact.copyConstructor(c);
1668 }
1669 }
1670
1671 throw new InternalError("Enclosing constructor not found");
1672 }
1673 }
1674
1675
1676 /**
1677 * If the class or interface represented by this {@code Class} object
1678 * is a member of another class, returns the {@code Class} object
1679 * representing the class in which it was declared. This method returns
1680 * null if this class or interface is not a member of any other class. If
1681 * this {@code Class} object represents an array class, a primitive
1682 * type, or void, then this method returns null.
1683 *
1684 * @return the declaring class for this class
1685 * @since 1.1
1686 */
1687 public Class<?> getDeclaringClass() {
1688 return getDeclaringClass0();
1689 }
1690
1691 private native Class<?> getDeclaringClass0();
1692
1693
1694 /**
1695 * Returns the immediately enclosing class of the underlying
1696 * class. If the underlying class is a top level class this
1697 * method returns {@code null}.
1698 * @return the immediately enclosing class of the underlying class
1699 * @since 1.5
1700 */
1701 public Class<?> getEnclosingClass() {
1702 // There are five kinds of classes (or interfaces):
1703 // a) Top level classes
1704 // b) Nested classes (static member classes)
1705 // c) Inner classes (non-static member classes)
1706 // d) Local classes (named classes declared within a method)
1707 // e) Anonymous classes
1708
1709
1710 // JVM Spec 4.7.7: A class must have an EnclosingMethod
1711 // attribute if and only if it is a local class or an
1712 // anonymous class.
1713 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1714 Class<?> enclosingCandidate;
1715
1716 if (enclosingInfo == null) {
1717 // This is a top level or a nested class or an inner class (a, b, or c)
1718 enclosingCandidate = getDeclaringClass0();
1719 } else {
1720 Class<?> enclosingClass = enclosingInfo.getEnclosingClass();
1721 // This is a local class or an anonymous class (d or e)
1722 if (enclosingClass == this || enclosingClass == null)
1723 throw new InternalError("Malformed enclosing method information");
1724 else
1725 enclosingCandidate = enclosingClass;
1726 }
1727 return enclosingCandidate;
1728 }
1729
1730 /**
1731 * Returns the simple name of the underlying class as given in the
1732 * source code. An empty string is returned if the underlying class is
1733 * {@linkplain #isAnonymousClass() anonymous}.
1734 * A {@linkplain #isSynthetic() synthetic class}, one not present
1735 * in source code, can have a non-empty name including special
1736 * characters, such as "{@code $}".
1737 *
1738 * <p>The simple name of an {@linkplain #isArray() array class} is the simple name of the
1739 * component type with "[]" appended. In particular the simple
1740 * name of an array class whose component type is anonymous is "[]".
1741 *
1742 * @return the simple name of the underlying class
1743 * @since 1.5
1744 */
1745 public String getSimpleName() {
1746 ReflectionData<T> rd = reflectionData();
1747 String simpleName = rd.simpleName;
1748 if (simpleName == null) {
1749 rd.simpleName = simpleName = getSimpleName0();
1750 }
1751 return simpleName;
1752 }
1753
1754 private String getSimpleName0() {
1755 if (isArray()) {
1756 return getComponentType().getSimpleName().concat("[]");
1757 }
1758 String simpleName = getSimpleBinaryName();
1759 if (simpleName == null) { // top level class
1760 simpleName = getName();
1761 simpleName = simpleName.substring(simpleName.lastIndexOf('.') + 1); // strip the package name
1762 }
1763 return simpleName;
1764 }
1765
1766 /**
1767 * Return an informative string for the name of this class or interface.
1768 *
1769 * @return an informative string for the name of this class or interface
1770 * @since 1.8
1771 */
1772 public String getTypeName() {
1773 if (isArray()) {
1774 try {
1775 Class<?> cl = this;
1776 int dimensions = 0;
1777 do {
1778 dimensions++;
1779 cl = cl.getComponentType();
1780 } while (cl.isArray());
1781 return cl.getName().concat("[]".repeat(dimensions));
1782 } catch (Throwable e) { /*FALLTHRU*/ }
1783 }
1784 return getName();
1785 }
1786
1787 /**
1788 * Returns the canonical name of the underlying class as
1789 * defined by <cite>The Java Language Specification</cite>.
1790 * Returns {@code null} if the underlying class does not have a canonical
1791 * name. Classes without canonical names include:
1792 * <ul>
1793 * <li>a {@linkplain #isLocalClass() local class}
1794 * <li>a {@linkplain #isAnonymousClass() anonymous class}
1795 * <li>a {@linkplain #isHidden() hidden class}
1796 * <li>an array whose component type does not have a canonical name</li>
1797 * </ul>
1798 *
1799 * The canonical name for a primitive class is the keyword for the
1800 * corresponding primitive type ({@code byte}, {@code short},
1801 * {@code char}, {@code int}, and so on).
1802 *
1803 * <p>An array type has a canonical name if and only if its
1804 * component type has a canonical name. When an array type has a
1805 * canonical name, it is equal to the canonical name of the
1806 * component type followed by "{@code []}".
1807 *
1808 * @return the canonical name of the underlying class if it exists, and
1809 * {@code null} otherwise.
1810 * @jls 6.7 Fully Qualified Names and Canonical Names
1811 * @since 1.5
1812 */
1813 public String getCanonicalName() {
1814 ReflectionData<T> rd = reflectionData();
1815 String canonicalName = rd.canonicalName;
1816 if (canonicalName == null) {
1817 rd.canonicalName = canonicalName = getCanonicalName0();
1818 }
1819 return canonicalName == ReflectionData.NULL_SENTINEL? null : canonicalName;
1820 }
1821
1822 private String getCanonicalName0() {
1823 if (isArray()) {
1824 String canonicalName = getComponentType().getCanonicalName();
1825 if (canonicalName != null)
1826 return canonicalName.concat("[]");
1827 else
1828 return ReflectionData.NULL_SENTINEL;
1829 }
1830 if (isHidden() || isLocalOrAnonymousClass())
1831 return ReflectionData.NULL_SENTINEL;
1832 Class<?> enclosingClass = getEnclosingClass();
1833 if (enclosingClass == null) { // top level class
1834 return getName();
1835 } else {
1836 String enclosingName = enclosingClass.getCanonicalName();
1837 if (enclosingName == null)
1838 return ReflectionData.NULL_SENTINEL;
1839 String simpleName = getSimpleName();
1840 return new StringBuilder(enclosingName.length() + simpleName.length() + 1)
1841 .append(enclosingName)
1842 .append('.')
1843 .append(simpleName)
1844 .toString();
1845 }
1846 }
1847
1848 /**
1849 * Returns {@code true} if and only if the underlying class
1850 * is an anonymous class.
1851 *
1852 * @apiNote
1853 * An anonymous class is not a {@linkplain #isHidden() hidden class}.
1854 *
1855 * @return {@code true} if and only if this class is an anonymous class.
1856 * @since 1.5
1857 * @jls 15.9.5 Anonymous Class Declarations
1858 */
1859 public boolean isAnonymousClass() {
1860 return !isArray() && isLocalOrAnonymousClass() &&
1861 getSimpleBinaryName0() == null;
1862 }
1863
1864 /**
1865 * Returns {@code true} if and only if the underlying class
1866 * is a local class.
1867 *
1868 * @return {@code true} if and only if this class is a local class.
1869 * @since 1.5
1870 * @jls 14.3 Local Class and Interface Declarations
1871 */
1872 public boolean isLocalClass() {
1873 return isLocalOrAnonymousClass() &&
1874 (isArray() || getSimpleBinaryName0() != null);
1875 }
1876
1877 /**
1878 * Returns {@code true} if and only if the underlying class
1879 * is a member class.
1880 *
1881 * @return {@code true} if and only if this class is a member class.
1882 * @since 1.5
1883 * @jls 8.5 Member Class and Interface Declarations
1884 */
1885 public boolean isMemberClass() {
1886 return !isLocalOrAnonymousClass() && getDeclaringClass0() != null;
1887 }
1888
1889 /**
1890 * Returns the "simple binary name" of the underlying class, i.e.,
1891 * the binary name without the leading enclosing class name.
1892 * Returns {@code null} if the underlying class is a top level
1893 * class.
1894 */
1895 private String getSimpleBinaryName() {
1896 if (isTopLevelClass())
1897 return null;
1898 String name = getSimpleBinaryName0();
1899 if (name == null) // anonymous class
1900 return "";
1901 return name;
1902 }
1903
1904 private native String getSimpleBinaryName0();
1905
1906 /**
1907 * Returns {@code true} if this is a top level class. Returns {@code false}
1908 * otherwise.
1909 */
1910 private boolean isTopLevelClass() {
1911 return !isLocalOrAnonymousClass() && getDeclaringClass0() == null;
1912 }
1913
1914 /**
1915 * Returns {@code true} if this is a local class or an anonymous
1916 * class. Returns {@code false} otherwise.
1917 */
1918 private boolean isLocalOrAnonymousClass() {
1919 // JVM Spec 4.7.7: A class must have an EnclosingMethod
1920 // attribute if and only if it is a local class or an
1921 // anonymous class.
1922 return hasEnclosingMethodInfo();
1923 }
1924
1925 private boolean hasEnclosingMethodInfo() {
1926 Object[] enclosingInfo = getEnclosingMethod0();
1927 if (enclosingInfo != null) {
1928 EnclosingMethodInfo.validate(enclosingInfo);
1929 return true;
1930 }
1931 return false;
1932 }
1933
1934 /**
1935 * Returns an array containing {@code Class} objects representing all
1936 * the public classes and interfaces that are members of the class
1937 * represented by this {@code Class} object. This includes public
1938 * class and interface members inherited from superclasses and public class
1939 * and interface members declared by the class. This method returns an
1940 * array of length 0 if this {@code Class} object has no public member
1941 * classes or interfaces. This method also returns an array of length 0 if
1942 * this {@code Class} object represents a primitive type, an array
1943 * class, or void.
1944 *
1945 * @return the array of {@code Class} objects representing the public
1946 * members of this class
1947 * @since 1.1
1948 */
1949 public Class<?>[] getClasses() {
1950 List<Class<?>> list = new ArrayList<>();
1951 Class<?> currentClass = Class.this;
1952 while (currentClass != null) {
1953 for (Class<?> m : currentClass.getDeclaredClasses()) {
1954 if (Modifier.isPublic(m.getModifiers())) {
1955 list.add(m);
1956 }
1957 }
1958 currentClass = currentClass.getSuperclass();
1959 }
1960 return list.toArray(new Class<?>[0]);
1961 }
1962
1963
1964 /**
1965 * Returns an array containing {@code Field} objects reflecting all
1966 * the accessible public fields of the class or interface represented by
1967 * this {@code Class} object.
1968 *
1969 * <p> If this {@code Class} object represents a class or interface with
1970 * no accessible public fields, then this method returns an array of length
1971 * 0.
1972 *
1973 * <p> If this {@code Class} object represents a class, then this method
1974 * returns the public fields of the class and of all its superclasses and
1975 * superinterfaces.
1976 *
1977 * <p> If this {@code Class} object represents an interface, then this
1978 * method returns the fields of the interface and of all its
1979 * superinterfaces.
1980 *
1981 * <p> If this {@code Class} object represents an array type, a primitive
1982 * type, or void, then this method returns an array of length 0.
1983 *
1984 * <p> The elements in the returned array are not sorted and are not in any
1985 * particular order.
1986 *
1987 * @return the array of {@code Field} objects representing the
1988 * public fields
1989 *
1990 * @since 1.1
1991 * @jls 8.2 Class Members
1992 * @jls 8.3 Field Declarations
1993 */
1994 public Field[] getFields() {
1995 return copyFields(privateGetPublicFields());
1996 }
1997
1998
1999 /**
2000 * Returns an array containing {@code Method} objects reflecting all the
2001 * public methods of the class or interface represented by this {@code
2002 * Class} object, including those declared by the class or interface and
2003 * those inherited from superclasses and superinterfaces.
2004 *
2005 * <p> If this {@code Class} object represents an array type, then the
2006 * returned array has a {@code Method} object for each of the public
2007 * methods inherited by the array type from {@code Object}. It does not
2008 * contain a {@code Method} object for {@code clone()}.
2009 *
2010 * <p> If this {@code Class} object represents an interface then the
2011 * returned array does not contain any implicitly declared methods from
2012 * {@code Object}. Therefore, if no methods are explicitly declared in
2013 * this interface or any of its superinterfaces then the returned array
2014 * has length 0. (Note that a {@code Class} object which represents a class
2015 * always has public methods, inherited from {@code Object}.)
2016 *
2017 * <p> The returned array never contains methods with names {@value
2018 * ConstantDescs#INIT_NAME} or {@value ConstantDescs#CLASS_INIT_NAME}.
2019 *
2020 * <p> The elements in the returned array are not sorted and are not in any
2021 * particular order.
2022 *
2023 * <p> Generally, the result is computed as with the following 4 step algorithm.
2024 * Let C be the class or interface represented by this {@code Class} object:
2025 * <ol>
2026 * <li> A union of methods is composed of:
2027 * <ol type="a">
2028 * <li> C's declared public instance and static methods as returned by
2029 * {@link #getDeclaredMethods()} and filtered to include only public
2030 * methods.</li>
2031 * <li> If C is a class other than {@code Object}, then include the result
2032 * of invoking this algorithm recursively on the superclass of C.</li>
2033 * <li> Include the results of invoking this algorithm recursively on all
2034 * direct superinterfaces of C, but include only instance methods.</li>
2035 * </ol></li>
2036 * <li> Union from step 1 is partitioned into subsets of methods with same
2037 * signature (name, parameter types) and return type.</li>
2038 * <li> Within each such subset only the most specific methods are selected.
2039 * Let method M be a method from a set of methods with same signature
2040 * and return type. M is most specific if there is no such method
2041 * N != M from the same set, such that N is more specific than M.
2042 * N is more specific than M if:
2043 * <ol type="a">
2044 * <li> N is declared by a class and M is declared by an interface; or</li>
2045 * <li> N and M are both declared by classes or both by interfaces and
2046 * N's declaring type is the same as or a subtype of M's declaring type
2047 * (clearly, if M's and N's declaring types are the same type, then
2048 * M and N are the same method).</li>
2049 * </ol></li>
2050 * <li> The result of this algorithm is the union of all selected methods from
2051 * step 3.</li>
2052 * </ol>
2053 *
2054 * @apiNote There may be more than one method with a particular name
2055 * and parameter types in a class because while the Java language forbids a
2056 * class to declare multiple methods with the same signature but different
2057 * return types, the Java virtual machine does not. This
2058 * increased flexibility in the virtual machine can be used to
2059 * implement various language features. For example, covariant
2060 * returns can be implemented with {@linkplain
2061 * java.lang.reflect.Method#isBridge bridge methods}; the bridge
2062 * method and the overriding method would have the same
2063 * signature but different return types.
2064 *
2065 * @return the array of {@code Method} objects representing the
2066 * public methods of this class
2067 *
2068 * @jls 8.2 Class Members
2069 * @jls 8.4 Method Declarations
2070 * @since 1.1
2071 */
2072 public Method[] getMethods() {
2073 return copyMethods(privateGetPublicMethods());
2074 }
2075
2076
2077 /**
2078 * Returns an array containing {@code Constructor} objects reflecting
2079 * all the public constructors of the class represented by this
2080 * {@code Class} object. An array of length 0 is returned if the
2081 * class has no public constructors, or if the class is an array class, or
2082 * if the class reflects a primitive type or void.
2083 *
2084 * @apiNote
2085 * While this method returns an array of {@code
2086 * Constructor<T>} objects (that is an array of constructors from
2087 * this class), the return type of this method is {@code
2088 * Constructor<?>[]} and <em>not</em> {@code Constructor<T>[]} as
2089 * might be expected. This less informative return type is
2090 * necessary since after being returned from this method, the
2091 * array could be modified to hold {@code Constructor} objects for
2092 * different classes, which would violate the type guarantees of
2093 * {@code Constructor<T>[]}.
2094 *
2095 * @return the array of {@code Constructor} objects representing the
2096 * public constructors of this class
2097 *
2098 * @see #getDeclaredConstructors()
2099 * @since 1.1
2100 */
2101 public Constructor<?>[] getConstructors() {
2102 return copyConstructors(privateGetDeclaredConstructors(true));
2103 }
2104
2105
2106 /**
2107 * Returns a {@code Field} object that reflects the specified public member
2108 * field of the class or interface represented by this {@code Class}
2109 * object. The {@code name} parameter is a {@code String} specifying the
2110 * simple name of the desired field.
2111 *
2112 * <p> The field to be reflected is determined by the algorithm that
2113 * follows. Let C be the class or interface represented by this {@code Class} object:
2114 *
2115 * <OL>
2116 * <LI> If C declares a public field with the name specified, that is the
2117 * field to be reflected.</LI>
2118 * <LI> If no field was found in step 1 above, this algorithm is applied
2119 * recursively to each direct superinterface of C. The direct
2120 * superinterfaces are searched in the order they were declared.</LI>
2121 * <LI> If no field was found in steps 1 and 2 above, and C has a
2122 * superclass S, then this algorithm is invoked recursively upon S.
2123 * If C has no superclass, then a {@code NoSuchFieldException}
2124 * is thrown.</LI>
2125 * </OL>
2126 *
2127 * <p> If this {@code Class} object represents an array type, then this
2128 * method does not find the {@code length} field of the array type.
2129 *
2130 * @param name the field name
2131 * @return the {@code Field} object of this class specified by
2132 * {@code name}
2133 * @throws NoSuchFieldException if a field with the specified name is
2134 * not found.
2135 * @throws NullPointerException if {@code name} is {@code null}
2136 *
2137 * @since 1.1
2138 * @jls 8.2 Class Members
2139 * @jls 8.3 Field Declarations
2140 */
2141 public Field getField(String name) throws NoSuchFieldException {
2142 Objects.requireNonNull(name);
2143 Field field = getField0(name);
2144 if (field == null) {
2145 throw new NoSuchFieldException(name);
2146 }
2147 return getReflectionFactory().copyField(field);
2148 }
2149
2150
2151 /**
2152 * Returns a {@code Method} object that reflects the specified public
2153 * member method of the class or interface represented by this
2154 * {@code Class} object. The {@code name} parameter is a
2155 * {@code String} specifying the simple name of the desired method. The
2156 * {@code parameterTypes} parameter is an array of {@code Class}
2157 * objects that identify the method's formal parameter types, in declared
2158 * order. If {@code parameterTypes} is {@code null}, it is
2159 * treated as if it were an empty array.
2160 *
2161 * <p> If this {@code Class} object represents an array type, then this
2162 * method finds any public method inherited by the array type from
2163 * {@code Object} except method {@code clone()}.
2164 *
2165 * <p> If this {@code Class} object represents an interface then this
2166 * method does not find any implicitly declared method from
2167 * {@code Object}. Therefore, if no methods are explicitly declared in
2168 * this interface or any of its superinterfaces, then this method does not
2169 * find any method.
2170 *
2171 * <p> This method does not find any method with name {@value
2172 * ConstantDescs#INIT_NAME} or {@value ConstantDescs#CLASS_INIT_NAME}.
2173 *
2174 * <p> Generally, the method to be reflected is determined by the 4 step
2175 * algorithm that follows.
2176 * Let C be the class or interface represented by this {@code Class} object:
2177 * <ol>
2178 * <li> A union of methods is composed of:
2179 * <ol type="a">
2180 * <li> C's declared public instance and static methods as returned by
2181 * {@link #getDeclaredMethods()} and filtered to include only public
2182 * methods that match given {@code name} and {@code parameterTypes}</li>
2183 * <li> If C is a class other than {@code Object}, then include the result
2184 * of invoking this algorithm recursively on the superclass of C.</li>
2185 * <li> Include the results of invoking this algorithm recursively on all
2186 * direct superinterfaces of C, but include only instance methods.</li>
2187 * </ol></li>
2188 * <li> This union is partitioned into subsets of methods with same
2189 * return type (the selection of methods from step 1 also guarantees that
2190 * they have the same method name and parameter types).</li>
2191 * <li> Within each such subset only the most specific methods are selected.
2192 * Let method M be a method from a set of methods with same VM
2193 * signature (return type, name, parameter types).
2194 * M is most specific if there is no such method N != M from the same
2195 * set, such that N is more specific than M. N is more specific than M
2196 * if:
2197 * <ol type="a">
2198 * <li> N is declared by a class and M is declared by an interface; or</li>
2199 * <li> N and M are both declared by classes or both by interfaces and
2200 * N's declaring type is the same as or a subtype of M's declaring type
2201 * (clearly, if M's and N's declaring types are the same type, then
2202 * M and N are the same method).</li>
2203 * </ol></li>
2204 * <li> The result of this algorithm is chosen arbitrarily from the methods
2205 * with most specific return type among all selected methods from step 3.
2206 * Let R be a return type of a method M from the set of all selected methods
2207 * from step 3. M is a method with most specific return type if there is
2208 * no such method N != M from the same set, having return type S != R,
2209 * such that S is a subtype of R as determined by
2210 * R.class.{@link #isAssignableFrom}(S.class).
2211 * </ol>
2212 *
2213 * @apiNote There may be more than one method with matching name and
2214 * parameter types in a class because while the Java language forbids a
2215 * class to declare multiple methods with the same signature but different
2216 * return types, the Java virtual machine does not. This
2217 * increased flexibility in the virtual machine can be used to
2218 * implement various language features. For example, covariant
2219 * returns can be implemented with {@linkplain
2220 * java.lang.reflect.Method#isBridge bridge methods}; the bridge
2221 * method and the overriding method would have the same
2222 * signature but different return types. This method would return the
2223 * overriding method as it would have a more specific return type.
2224 *
2225 * @param name the name of the method
2226 * @param parameterTypes the list of parameters
2227 * @return the {@code Method} object that matches the specified
2228 * {@code name} and {@code parameterTypes}
2229 * @throws NoSuchMethodException if a matching method is not found
2230 * or if the name is {@value ConstantDescs#INIT_NAME} or
2231 * {@value ConstantDescs#CLASS_INIT_NAME}.
2232 * @throws NullPointerException if {@code name} is {@code null}
2233 *
2234 * @jls 8.2 Class Members
2235 * @jls 8.4 Method Declarations
2236 * @since 1.1
2237 */
2238 public Method getMethod(String name, Class<?>... parameterTypes)
2239 throws NoSuchMethodException {
2240 Objects.requireNonNull(name);
2241 Method method = getMethod0(name, parameterTypes);
2242 if (method == null) {
2243 throw new NoSuchMethodException(methodToString(name, parameterTypes));
2244 }
2245 return getReflectionFactory().copyMethod(method);
2246 }
2247
2248 /**
2249 * Returns a {@code Constructor} object that reflects the specified
2250 * public constructor of the class represented by this {@code Class}
2251 * object. The {@code parameterTypes} parameter is an array of
2252 * {@code Class} objects that identify the constructor's formal
2253 * parameter types, in declared order.
2254 *
2255 * If this {@code Class} object represents an inner class
2256 * declared in a non-static context, the formal parameter types
2257 * include the explicit enclosing instance as the first parameter.
2258 *
2259 * <p> The constructor to reflect is the public constructor of the class
2260 * represented by this {@code Class} object whose formal parameter
2261 * types match those specified by {@code parameterTypes}.
2262 *
2263 * @param parameterTypes the parameter array
2264 * @return the {@code Constructor} object of the public constructor that
2265 * matches the specified {@code parameterTypes}
2266 * @throws NoSuchMethodException if a matching constructor is not found,
2267 * including when this {@code Class} object represents
2268 * an interface, a primitive type, an array class, or void.
2269 *
2270 * @see #getDeclaredConstructor(Class[])
2271 * @since 1.1
2272 */
2273 public Constructor<T> getConstructor(Class<?>... parameterTypes)
2274 throws NoSuchMethodException {
2275 return getReflectionFactory().copyConstructor(
2276 getConstructor0(parameterTypes, Member.PUBLIC));
2277 }
2278
2279
2280 /**
2281 * Returns an array of {@code Class} objects reflecting all the
2282 * classes and interfaces declared as members of the class represented by
2283 * this {@code Class} object. This includes public, protected, default
2284 * (package) access, and private classes and interfaces declared by the
2285 * class, but excludes inherited classes and interfaces. This method
2286 * returns an array of length 0 if the class declares no classes or
2287 * interfaces as members, or if this {@code Class} object represents a
2288 * primitive type, an array class, or void.
2289 *
2290 * @return the array of {@code Class} objects representing all the
2291 * declared members of this class
2292 *
2293 * @since 1.1
2294 * @jls 8.5 Member Class and Interface Declarations
2295 */
2296 public Class<?>[] getDeclaredClasses() {
2297 return getDeclaredClasses0();
2298 }
2299
2300
2301 /**
2302 * Returns an array of {@code Field} objects reflecting all the fields
2303 * declared by the class or interface represented by this
2304 * {@code Class} object. This includes public, protected, default
2305 * (package) access, and private fields, but excludes inherited fields.
2306 *
2307 * <p> If this {@code Class} object represents a class or interface with no
2308 * declared fields, then this method returns an array of length 0.
2309 *
2310 * <p> If this {@code Class} object represents an array type, a primitive
2311 * type, or void, then this method returns an array of length 0.
2312 *
2313 * <p> The elements in the returned array are not sorted and are not in any
2314 * particular order.
2315 *
2316 * @return the array of {@code Field} objects representing all the
2317 * declared fields of this class
2318 *
2319 * @since 1.1
2320 * @jls 8.2 Class Members
2321 * @jls 8.3 Field Declarations
2322 */
2323 public Field[] getDeclaredFields() {
2324 return copyFields(privateGetDeclaredFields(false));
2325 }
2326
2327 /**
2328 * Returns an array of {@code RecordComponent} objects representing all the
2329 * record components of this record class, or {@code null} if this class is
2330 * not a record class.
2331 *
2332 * <p> The components are returned in the same order that they are declared
2333 * in the record header. The array is empty if this record class has no
2334 * components. If the class is not a record class, that is {@link
2335 * #isRecord()} returns {@code false}, then this method returns {@code null}.
2336 * Conversely, if {@link #isRecord()} returns {@code true}, then this method
2337 * returns a non-null value.
2338 *
2339 * @apiNote
2340 * <p> The following method can be used to find the record canonical constructor:
2341 *
2342 * {@snippet lang="java" :
2343 * static <T extends Record> Constructor<T> getCanonicalConstructor(Class<T> cls)
2344 * throws NoSuchMethodException {
2345 * Class<?>[] paramTypes =
2346 * Arrays.stream(cls.getRecordComponents())
2347 * .map(RecordComponent::getType)
2348 * .toArray(Class<?>[]::new);
2349 * return cls.getDeclaredConstructor(paramTypes);
2350 * }}
2351 *
2352 * @return An array of {@code RecordComponent} objects representing all the
2353 * record components of this record class, or {@code null} if this
2354 * class is not a record class
2355 *
2356 * @jls 8.10 Record Classes
2357 * @since 16
2358 */
2359 public RecordComponent[] getRecordComponents() {
2360 if (!isRecord()) {
2361 return null;
2362 }
2363 return getRecordComponents0();
2364 }
2365
2366 /**
2367 * Returns an array containing {@code Method} objects reflecting all the
2368 * declared methods of the class or interface represented by this {@code
2369 * Class} object, including public, protected, default (package)
2370 * access, and private methods, but excluding inherited methods.
2371 * The declared methods may include methods <em>not</em> in the
2372 * source of the class or interface, including {@linkplain
2373 * Method#isBridge bridge methods} and other {@linkplain
2374 * Executable#isSynthetic synthetic} methods added by compilers.
2375 *
2376 * <p> If this {@code Class} object represents a class or interface that
2377 * has multiple declared methods with the same name and parameter types,
2378 * but different return types, then the returned array has a {@code Method}
2379 * object for each such method.
2380 *
2381 * <p> If this {@code Class} object represents a class or interface that
2382 * has a class initialization method {@value ConstantDescs#CLASS_INIT_NAME},
2383 * then the returned array does <em>not</em> have a corresponding {@code
2384 * Method} object.
2385 *
2386 * <p> If this {@code Class} object represents a class or interface with no
2387 * declared methods, then the returned array has length 0.
2388 *
2389 * <p> If this {@code Class} object represents an array type, a primitive
2390 * type, or void, then the returned array has length 0.
2391 *
2392 * <p> The elements in the returned array are not sorted and are not in any
2393 * particular order.
2394 *
2395 * @return the array of {@code Method} objects representing all the
2396 * declared methods of this class
2397 *
2398 * @jls 8.2 Class Members
2399 * @jls 8.4 Method Declarations
2400 * @see <a
2401 * href="{@docRoot}/java.base/java/lang/reflect/package-summary.html#LanguageJvmModel">Java
2402 * programming language and JVM modeling in core reflection</a>
2403 * @since 1.1
2404 */
2405 public Method[] getDeclaredMethods() {
2406 return copyMethods(privateGetDeclaredMethods(false));
2407 }
2408
2409 /**
2410 * Returns an array of {@code Constructor} objects reflecting all the
2411 * constructors implicitly or explicitly declared by the class represented by this
2412 * {@code Class} object. These are public, protected, default
2413 * (package) access, and private constructors. The elements in the array
2414 * returned are not sorted and are not in any particular order. If the
2415 * class has a default constructor (JLS {@jls 8.8.9}), it is included in the returned array.
2416 * If a record class has a canonical constructor (JLS {@jls
2417 * 8.10.4.1}, {@jls 8.10.4.2}), it is included in the returned array.
2418 *
2419 * This method returns an array of length 0 if this {@code Class}
2420 * object represents an interface, a primitive type, an array class, or
2421 * void.
2422 *
2423 * @return the array of {@code Constructor} objects representing all the
2424 * declared constructors of this class
2425 *
2426 * @since 1.1
2427 * @see #getConstructors()
2428 * @jls 8.8 Constructor Declarations
2429 */
2430 public Constructor<?>[] getDeclaredConstructors() {
2431 return copyConstructors(privateGetDeclaredConstructors(false));
2432 }
2433
2434
2435 /**
2436 * Returns a {@code Field} object that reflects the specified declared
2437 * field of the class or interface represented by this {@code Class}
2438 * object. The {@code name} parameter is a {@code String} that specifies
2439 * the simple name of the desired field.
2440 *
2441 * <p> If this {@code Class} object represents an array type, then this
2442 * method does not find the {@code length} field of the array type.
2443 *
2444 * @param name the name of the field
2445 * @return the {@code Field} object for the specified field in this
2446 * class
2447 * @throws NoSuchFieldException if a field with the specified name is
2448 * not found.
2449 * @throws NullPointerException if {@code name} is {@code null}
2450 *
2451 * @since 1.1
2452 * @jls 8.2 Class Members
2453 * @jls 8.3 Field Declarations
2454 */
2455 public Field getDeclaredField(String name) throws NoSuchFieldException {
2456 Objects.requireNonNull(name);
2457 Field field = searchFields(privateGetDeclaredFields(false), name);
2458 if (field == null) {
2459 throw new NoSuchFieldException(name);
2460 }
2461 return getReflectionFactory().copyField(field);
2462 }
2463
2464
2465 /**
2466 * Returns a {@code Method} object that reflects the specified
2467 * declared method of the class or interface represented by this
2468 * {@code Class} object. The {@code name} parameter is a
2469 * {@code String} that specifies the simple name of the desired
2470 * method, and the {@code parameterTypes} parameter is an array of
2471 * {@code Class} objects that identify the method's formal parameter
2472 * types, in declared order. If more than one method with the same
2473 * parameter types is declared in a class, and one of these methods has a
2474 * return type that is more specific than any of the others, that method is
2475 * returned; otherwise one of the methods is chosen arbitrarily. If the
2476 * name is {@value ConstantDescs#INIT_NAME} or {@value
2477 * ConstantDescs#CLASS_INIT_NAME} a {@code NoSuchMethodException}
2478 * is raised.
2479 *
2480 * <p> If this {@code Class} object represents an array type, then this
2481 * method does not find the {@code clone()} method.
2482 *
2483 * @param name the name of the method
2484 * @param parameterTypes the parameter array
2485 * @return the {@code Method} object for the method of this class
2486 * matching the specified name and parameters
2487 * @throws NoSuchMethodException if a matching method is not found.
2488 * @throws NullPointerException if {@code name} is {@code null}
2489 *
2490 * @jls 8.2 Class Members
2491 * @jls 8.4 Method Declarations
2492 * @since 1.1
2493 */
2494 public Method getDeclaredMethod(String name, Class<?>... parameterTypes)
2495 throws NoSuchMethodException {
2496 Objects.requireNonNull(name);
2497 Method method = searchMethods(privateGetDeclaredMethods(false), name, parameterTypes);
2498 if (method == null) {
2499 throw new NoSuchMethodException(methodToString(name, parameterTypes));
2500 }
2501 return getReflectionFactory().copyMethod(method);
2502 }
2503
2504 /**
2505 * Returns the list of {@code Method} objects for the declared public
2506 * methods of this class or interface that have the specified method name
2507 * and parameter types.
2508 *
2509 * @param name the name of the method
2510 * @param parameterTypes the parameter array
2511 * @return the list of {@code Method} objects for the public methods of
2512 * this class matching the specified name and parameters
2513 */
2514 List<Method> getDeclaredPublicMethods(String name, Class<?>... parameterTypes) {
2515 Method[] methods = privateGetDeclaredMethods(/* publicOnly */ true);
2516 ReflectionFactory factory = getReflectionFactory();
2517 List<Method> result = new ArrayList<>();
2518 for (Method method : methods) {
2519 if (method.getName().equals(name)
2520 && Arrays.equals(
2521 factory.getExecutableSharedParameterTypes(method),
2522 parameterTypes)) {
2523 result.add(factory.copyMethod(method));
2524 }
2525 }
2526 return result;
2527 }
2528
2529 /**
2530 * Returns the most specific {@code Method} object of this class, super class or
2531 * interface that have the specified method name and parameter types.
2532 *
2533 * @param publicOnly true if only public methods are examined, otherwise all methods
2534 * @param name the name of the method
2535 * @param parameterTypes the parameter array
2536 * @return the {@code Method} object for the method found from this class matching
2537 * the specified name and parameters, or null if not found
2538 */
2539 Method findMethod(boolean publicOnly, String name, Class<?>... parameterTypes) {
2540 PublicMethods.MethodList res = getMethodsRecursive(name, parameterTypes, true, publicOnly);
2541 return res == null ? null : getReflectionFactory().copyMethod(res.getMostSpecific());
2542 }
2543
2544 /**
2545 * Returns a {@code Constructor} object that reflects the specified
2546 * constructor of the class represented by this
2547 * {@code Class} object. The {@code parameterTypes} parameter is
2548 * an array of {@code Class} objects that identify the constructor's
2549 * formal parameter types, in declared order.
2550 *
2551 * If this {@code Class} object represents an inner class
2552 * declared in a non-static context, the formal parameter types
2553 * include the explicit enclosing instance as the first parameter.
2554 *
2555 * @param parameterTypes the parameter array
2556 * @return The {@code Constructor} object for the constructor with the
2557 * specified parameter list
2558 * @throws NoSuchMethodException if a matching constructor is not found,
2559 * including when this {@code Class} object represents
2560 * an interface, a primitive type, an array class, or void.
2561 *
2562 * @see #getConstructor(Class[])
2563 * @since 1.1
2564 */
2565 public Constructor<T> getDeclaredConstructor(Class<?>... parameterTypes)
2566 throws NoSuchMethodException {
2567 return getReflectionFactory().copyConstructor(
2568 getConstructor0(parameterTypes, Member.DECLARED));
2569 }
2570
2571 /**
2572 * Finds a resource with a given name.
2573 *
2574 * <p> If this class is in a named {@link Module Module} then this method
2575 * will attempt to find the resource in the module. This is done by
2576 * delegating to the module's class loader {@link
2577 * ClassLoader#findResource(String,String) findResource(String,String)}
2578 * method, invoking it with the module name and the absolute name of the
2579 * resource. Resources in named modules are subject to the rules for
2580 * encapsulation specified in the {@code Module} {@link
2581 * Module#getResourceAsStream getResourceAsStream} method and so this
2582 * method returns {@code null} when the resource is a
2583 * non-"{@code .class}" resource in a package that is not open to the
2584 * caller's module.
2585 *
2586 * <p> Otherwise, if this class is not in a named module then the rules for
2587 * searching resources associated with a given class are implemented by the
2588 * defining {@linkplain ClassLoader class loader} of the class. This method
2589 * delegates to this {@code Class} object's class loader.
2590 * If this {@code Class} object was loaded by the bootstrap class loader,
2591 * the method delegates to {@link ClassLoader#getSystemResourceAsStream}.
2592 *
2593 * <p> Before delegation, an absolute resource name is constructed from the
2594 * given resource name using this algorithm:
2595 *
2596 * <ul>
2597 *
2598 * <li> If the {@code name} begins with a {@code '/'}
2599 * (<code>'\u002f'</code>), then the absolute name of the resource is the
2600 * portion of the {@code name} following the {@code '/'}.
2601 *
2602 * <li> Otherwise, the absolute name is of the following form:
2603 *
2604 * <blockquote>
2605 * {@code modified_package_name/name}
2606 * </blockquote>
2607 *
2608 * <p> Where the {@code modified_package_name} is the package name of this
2609 * object with {@code '/'} substituted for {@code '.'}
2610 * (<code>'\u002e'</code>).
2611 *
2612 * </ul>
2613 *
2614 * @param name name of the desired resource
2615 * @return A {@link java.io.InputStream} object; {@code null} if no
2616 * resource with this name is found, or the resource is in a package
2617 * that is not {@linkplain Module#isOpen(String, Module) open} to at
2618 * least the caller module.
2619 * @throws NullPointerException If {@code name} is {@code null}
2620 *
2621 * @see Module#getResourceAsStream(String)
2622 * @since 1.1
2623 */
2624 @CallerSensitive
2625 public InputStream getResourceAsStream(String name) {
2626 name = resolveName(name);
2627
2628 Module thisModule = getModule();
2629 if (thisModule.isNamed()) {
2630 // check if resource can be located by caller
2631 if (Resources.canEncapsulate(name)
2632 && !isOpenToCaller(name, Reflection.getCallerClass())) {
2633 return null;
2634 }
2635
2636 // resource not encapsulated or in package open to caller
2637 String mn = thisModule.getName();
2638 ClassLoader cl = classLoader;
2639 try {
2640
2641 // special-case built-in class loaders to avoid the
2642 // need for a URL connection
2643 if (cl == null) {
2644 return BootLoader.findResourceAsStream(mn, name);
2645 } else if (cl instanceof BuiltinClassLoader bcl) {
2646 return bcl.findResourceAsStream(mn, name);
2647 } else {
2648 URL url = cl.findResource(mn, name);
2649 return (url != null) ? url.openStream() : null;
2650 }
2651
2652 } catch (IOException | SecurityException e) {
2653 return null;
2654 }
2655 }
2656
2657 // unnamed module
2658 ClassLoader cl = classLoader;
2659 if (cl == null) {
2660 return ClassLoader.getSystemResourceAsStream(name);
2661 } else {
2662 return cl.getResourceAsStream(name);
2663 }
2664 }
2665
2666 /**
2667 * Finds a resource with a given name.
2668 *
2669 * <p> If this class is in a named {@link Module Module} then this method
2670 * will attempt to find the resource in the module. This is done by
2671 * delegating to the module's class loader {@link
2672 * ClassLoader#findResource(String,String) findResource(String,String)}
2673 * method, invoking it with the module name and the absolute name of the
2674 * resource. Resources in named modules are subject to the rules for
2675 * encapsulation specified in the {@code Module} {@link
2676 * Module#getResourceAsStream getResourceAsStream} method and so this
2677 * method returns {@code null} when the resource is a
2678 * non-"{@code .class}" resource in a package that is not open to the
2679 * caller's module.
2680 *
2681 * <p> Otherwise, if this class is not in a named module then the rules for
2682 * searching resources associated with a given class are implemented by the
2683 * defining {@linkplain ClassLoader class loader} of the class. This method
2684 * delegates to this {@code Class} object's class loader.
2685 * If this {@code Class} object was loaded by the bootstrap class loader,
2686 * the method delegates to {@link ClassLoader#getSystemResource}.
2687 *
2688 * <p> Before delegation, an absolute resource name is constructed from the
2689 * given resource name using this algorithm:
2690 *
2691 * <ul>
2692 *
2693 * <li> If the {@code name} begins with a {@code '/'}
2694 * (<code>'\u002f'</code>), then the absolute name of the resource is the
2695 * portion of the {@code name} following the {@code '/'}.
2696 *
2697 * <li> Otherwise, the absolute name is of the following form:
2698 *
2699 * <blockquote>
2700 * {@code modified_package_name/name}
2701 * </blockquote>
2702 *
2703 * <p> Where the {@code modified_package_name} is the package name of this
2704 * object with {@code '/'} substituted for {@code '.'}
2705 * (<code>'\u002e'</code>).
2706 *
2707 * </ul>
2708 *
2709 * @param name name of the desired resource
2710 * @return A {@link java.net.URL} object; {@code null} if no resource with
2711 * this name is found, the resource cannot be located by a URL, or the
2712 * resource is in a package that is not
2713 * {@linkplain Module#isOpen(String, Module) open} to at least the caller
2714 * module.
2715 * @throws NullPointerException If {@code name} is {@code null}
2716 * @since 1.1
2717 */
2718 @CallerSensitive
2719 public URL getResource(String name) {
2720 name = resolveName(name);
2721
2722 Module thisModule = getModule();
2723 if (thisModule.isNamed()) {
2724 // check if resource can be located by caller
2725 if (Resources.canEncapsulate(name)
2726 && !isOpenToCaller(name, Reflection.getCallerClass())) {
2727 return null;
2728 }
2729
2730 // resource not encapsulated or in package open to caller
2731 String mn = thisModule.getName();
2732 ClassLoader cl = classLoader;
2733 try {
2734 if (cl == null) {
2735 return BootLoader.findResource(mn, name);
2736 } else {
2737 return cl.findResource(mn, name);
2738 }
2739 } catch (IOException ioe) {
2740 return null;
2741 }
2742 }
2743
2744 // unnamed module
2745 ClassLoader cl = classLoader;
2746 if (cl == null) {
2747 return ClassLoader.getSystemResource(name);
2748 } else {
2749 return cl.getResource(name);
2750 }
2751 }
2752
2753 /**
2754 * Returns true if a resource with the given name can be located by the
2755 * given caller. All resources in a module can be located by code in
2756 * the module. For other callers, then the package needs to be open to
2757 * the caller.
2758 */
2759 private boolean isOpenToCaller(String name, Class<?> caller) {
2760 // assert getModule().isNamed();
2761 Module thisModule = getModule();
2762 Module callerModule = (caller != null) ? caller.getModule() : null;
2763 if (callerModule != thisModule) {
2764 String pn = Resources.toPackageName(name);
2765 if (thisModule.getDescriptor().packages().contains(pn)) {
2766 if (callerModule == null) {
2767 // no caller, return true if the package is open to all modules
2768 return thisModule.isOpen(pn);
2769 }
2770 if (!thisModule.isOpen(pn, callerModule)) {
2771 // package not open to caller
2772 return false;
2773 }
2774 }
2775 }
2776 return true;
2777 }
2778
2779 private transient final ProtectionDomain protectionDomain;
2780
2781 /** Holder for the protection domain returned when the internal domain is null */
2782 private static class Holder {
2783 private static final ProtectionDomain allPermDomain;
2784 static {
2785 Permissions perms = new Permissions();
2786 perms.add(new AllPermission());
2787 allPermDomain = new ProtectionDomain(null, perms);
2788 }
2789 }
2790
2791 /**
2792 * Returns the {@code ProtectionDomain} of this class.
2793 *
2794 * @return the ProtectionDomain of this class
2795 *
2796 * @see java.security.ProtectionDomain
2797 * @since 1.2
2798 */
2799 public ProtectionDomain getProtectionDomain() {
2800 if (protectionDomain == null) {
2801 return Holder.allPermDomain;
2802 } else {
2803 return protectionDomain;
2804 }
2805 }
2806
2807 /*
2808 * Returns the Class object for the named primitive type. Type parameter T
2809 * avoids redundant casts for trusted code.
2810 */
2811 static native <T> Class<T> getPrimitiveClass(String name);
2812
2813 /**
2814 * Add a package name prefix if the name is not absolute. Remove leading "/"
2815 * if name is absolute
2816 */
2817 private String resolveName(String name) {
2818 if (!name.startsWith("/")) {
2819 String baseName = getPackageName();
2820 if (!baseName.isEmpty()) {
2821 int len = baseName.length() + 1 + name.length();
2822 StringBuilder sb = new StringBuilder(len);
2823 name = sb.append(baseName.replace('.', '/'))
2824 .append('/')
2825 .append(name)
2826 .toString();
2827 }
2828 } else {
2829 name = name.substring(1);
2830 }
2831 return name;
2832 }
2833
2834 /**
2835 * Atomic operations support.
2836 */
2837 private static class Atomic {
2838 // initialize Unsafe machinery here, since we need to call Class.class instance method
2839 // and have to avoid calling it in the static initializer of the Class class...
2840 private static final Unsafe unsafe = Unsafe.getUnsafe();
2841 // offset of Class.reflectionData instance field
2842 private static final long reflectionDataOffset
2843 = unsafe.objectFieldOffset(Class.class, "reflectionData");
2844 // offset of Class.annotationType instance field
2845 private static final long annotationTypeOffset
2846 = unsafe.objectFieldOffset(Class.class, "annotationType");
2847 // offset of Class.annotationData instance field
2848 private static final long annotationDataOffset
2849 = unsafe.objectFieldOffset(Class.class, "annotationData");
2850
2851 static <T> boolean casReflectionData(Class<?> clazz,
2852 SoftReference<ReflectionData<T>> oldData,
2853 SoftReference<ReflectionData<T>> newData) {
2854 return unsafe.compareAndSetReference(clazz, reflectionDataOffset, oldData, newData);
2855 }
2856
2857 static boolean casAnnotationType(Class<?> clazz,
2858 AnnotationType oldType,
2859 AnnotationType newType) {
2860 return unsafe.compareAndSetReference(clazz, annotationTypeOffset, oldType, newType);
2861 }
2862
2863 static boolean casAnnotationData(Class<?> clazz,
2864 AnnotationData oldData,
2865 AnnotationData newData) {
2866 return unsafe.compareAndSetReference(clazz, annotationDataOffset, oldData, newData);
2867 }
2868 }
2869
2870 /**
2871 * Reflection support.
2872 */
2873
2874 // Reflection data caches various derived names and reflective members. Cached
2875 // values may be invalidated when JVM TI RedefineClasses() is called
2876 private static class ReflectionData<T> {
2877 volatile Field[] declaredFields;
2878 volatile Field[] publicFields;
2879 volatile Method[] declaredMethods;
2880 volatile Method[] publicMethods;
2881 volatile Constructor<T>[] declaredConstructors;
2882 volatile Constructor<T>[] publicConstructors;
2883 // Intermediate results for getFields and getMethods
2884 volatile Field[] declaredPublicFields;
2885 volatile Method[] declaredPublicMethods;
2886 volatile Class<?>[] interfaces;
2887
2888 // Cached names
2889 String simpleName;
2890 String canonicalName;
2891 static final String NULL_SENTINEL = new String();
2892
2893 // Value of classRedefinedCount when we created this ReflectionData instance
2894 final int redefinedCount;
2895
2896 ReflectionData(int redefinedCount) {
2897 this.redefinedCount = redefinedCount;
2898 }
2899 }
2900
2901 private transient volatile SoftReference<ReflectionData<T>> reflectionData;
2902
2903 // Incremented by the VM on each call to JVM TI RedefineClasses()
2904 // that redefines this class or a superclass.
2905 private transient volatile int classRedefinedCount;
2906
2907 // Lazily create and cache ReflectionData
2908 private ReflectionData<T> reflectionData() {
2909 SoftReference<ReflectionData<T>> reflectionData = this.reflectionData;
2910 int classRedefinedCount = this.classRedefinedCount;
2911 ReflectionData<T> rd;
2912 if (reflectionData != null &&
2913 (rd = reflectionData.get()) != null &&
2914 rd.redefinedCount == classRedefinedCount) {
2915 return rd;
2916 }
2917 // else no SoftReference or cleared SoftReference or stale ReflectionData
2918 // -> create and replace new instance
2919 return newReflectionData(reflectionData, classRedefinedCount);
2920 }
2921
2922 private ReflectionData<T> newReflectionData(SoftReference<ReflectionData<T>> oldReflectionData,
2923 int classRedefinedCount) {
2924 while (true) {
2925 ReflectionData<T> rd = new ReflectionData<>(classRedefinedCount);
2926 // try to CAS it...
2927 if (Atomic.casReflectionData(this, oldReflectionData, new SoftReference<>(rd))) {
2928 return rd;
2929 }
2930 // else retry
2931 oldReflectionData = this.reflectionData;
2932 classRedefinedCount = this.classRedefinedCount;
2933 if (oldReflectionData != null &&
2934 (rd = oldReflectionData.get()) != null &&
2935 rd.redefinedCount == classRedefinedCount) {
2936 return rd;
2937 }
2938 }
2939 }
2940
2941 // Generic signature handling
2942 private native String getGenericSignature0();
2943
2944 // Generic info repository; lazily initialized
2945 private transient volatile ClassRepository genericInfo;
2946
2947 // accessor for factory
2948 private GenericsFactory getFactory() {
2949 // create scope and factory
2950 return CoreReflectionFactory.make(this, ClassScope.make(this));
2951 }
2952
2953 // accessor for generic info repository;
2954 // generic info is lazily initialized
2955 private ClassRepository getGenericInfo() {
2956 ClassRepository genericInfo = this.genericInfo;
2957 if (genericInfo == null) {
2958 String signature = getGenericSignature0();
2959 if (signature == null) {
2960 genericInfo = ClassRepository.NONE;
2961 } else {
2962 genericInfo = ClassRepository.make(signature, getFactory());
2963 }
2964 this.genericInfo = genericInfo;
2965 }
2966 return (genericInfo != ClassRepository.NONE) ? genericInfo : null;
2967 }
2968
2969 // Annotations handling
2970 native byte[] getRawAnnotations();
2971 // Since 1.8
2972 native byte[] getRawTypeAnnotations();
2973 static byte[] getExecutableTypeAnnotationBytes(Executable ex) {
2974 return getReflectionFactory().getExecutableTypeAnnotationBytes(ex);
2975 }
2976
2977 native ConstantPool getConstantPool();
2978
2979 //
2980 //
2981 // java.lang.reflect.Field handling
2982 //
2983 //
2984
2985 // Returns an array of "root" fields. These Field objects must NOT
2986 // be propagated to the outside world, but must instead be copied
2987 // via ReflectionFactory.copyField.
2988 private Field[] privateGetDeclaredFields(boolean publicOnly) {
2989 Field[] res;
2990 ReflectionData<T> rd = reflectionData();
2991 res = publicOnly ? rd.declaredPublicFields : rd.declaredFields;
2992 if (res != null) return res;
2993 // No cached value available; request value from VM
2994 res = Reflection.filterFields(this, getDeclaredFields0(publicOnly));
2995 if (publicOnly) {
2996 rd.declaredPublicFields = res;
2997 } else {
2998 rd.declaredFields = res;
2999 }
3000 return res;
3001 }
3002
3003 // Returns an array of "root" fields. These Field objects must NOT
3004 // be propagated to the outside world, but must instead be copied
3005 // via ReflectionFactory.copyField.
3006 private Field[] privateGetPublicFields() {
3007 Field[] res;
3008 ReflectionData<T> rd = reflectionData();
3009 res = rd.publicFields;
3010 if (res != null) return res;
3011
3012 // Use a linked hash set to ensure order is preserved and
3013 // fields from common super interfaces are not duplicated
3014 LinkedHashSet<Field> fields = new LinkedHashSet<>();
3015
3016 // Local fields
3017 addAll(fields, privateGetDeclaredFields(true));
3018
3019 // Direct superinterfaces, recursively
3020 for (Class<?> si : getInterfaces(/* cloneArray */ false)) {
3021 addAll(fields, si.privateGetPublicFields());
3022 }
3023
3024 // Direct superclass, recursively
3025 Class<?> sc = getSuperclass();
3026 if (sc != null) {
3027 addAll(fields, sc.privateGetPublicFields());
3028 }
3029
3030 res = fields.toArray(new Field[0]);
3031 rd.publicFields = res;
3032 return res;
3033 }
3034
3035 private static void addAll(Collection<Field> c, Field[] o) {
3036 for (Field f : o) {
3037 c.add(f);
3038 }
3039 }
3040
3041
3042 //
3043 //
3044 // java.lang.reflect.Constructor handling
3045 //
3046 //
3047
3048 // Returns an array of "root" constructors. These Constructor
3049 // objects must NOT be propagated to the outside world, but must
3050 // instead be copied via ReflectionFactory.copyConstructor.
3051 private Constructor<T>[] privateGetDeclaredConstructors(boolean publicOnly) {
3052 Constructor<T>[] res;
3053 ReflectionData<T> rd = reflectionData();
3054 res = publicOnly ? rd.publicConstructors : rd.declaredConstructors;
3055 if (res != null) return res;
3056 // No cached value available; request value from VM
3057 if (isInterface()) {
3058 @SuppressWarnings("unchecked")
3059 Constructor<T>[] temporaryRes = (Constructor<T>[]) new Constructor<?>[0];
3060 res = temporaryRes;
3061 } else {
3062 res = getDeclaredConstructors0(publicOnly);
3063 }
3064 if (publicOnly) {
3065 rd.publicConstructors = res;
3066 } else {
3067 rd.declaredConstructors = res;
3068 }
3069 return res;
3070 }
3071
3072 //
3073 //
3074 // java.lang.reflect.Method handling
3075 //
3076 //
3077
3078 // Returns an array of "root" methods. These Method objects must NOT
3079 // be propagated to the outside world, but must instead be copied
3080 // via ReflectionFactory.copyMethod.
3081 private Method[] privateGetDeclaredMethods(boolean publicOnly) {
3082 Method[] res;
3083 ReflectionData<T> rd = reflectionData();
3084 res = publicOnly ? rd.declaredPublicMethods : rd.declaredMethods;
3085 if (res != null) return res;
3086 // No cached value available; request value from VM
3087 res = Reflection.filterMethods(this, getDeclaredMethods0(publicOnly));
3088 if (publicOnly) {
3089 rd.declaredPublicMethods = res;
3090 } else {
3091 rd.declaredMethods = res;
3092 }
3093 return res;
3094 }
3095
3096 // Returns an array of "root" methods. These Method objects must NOT
3097 // be propagated to the outside world, but must instead be copied
3098 // via ReflectionFactory.copyMethod.
3099 private Method[] privateGetPublicMethods() {
3100 Method[] res;
3101 ReflectionData<T> rd = reflectionData();
3102 res = rd.publicMethods;
3103 if (res != null) return res;
3104
3105 // No cached value available; compute value recursively.
3106 // Start by fetching public declared methods...
3107 PublicMethods pms = new PublicMethods();
3108 for (Method m : privateGetDeclaredMethods(/* publicOnly */ true)) {
3109 pms.merge(m);
3110 }
3111 // ...then recur over superclass methods...
3112 Class<?> sc = getSuperclass();
3113 if (sc != null) {
3114 for (Method m : sc.privateGetPublicMethods()) {
3115 pms.merge(m);
3116 }
3117 }
3118 // ...and finally over direct superinterfaces.
3119 for (Class<?> intf : getInterfaces(/* cloneArray */ false)) {
3120 for (Method m : intf.privateGetPublicMethods()) {
3121 // static interface methods are not inherited
3122 if (!Modifier.isStatic(m.getModifiers())) {
3123 pms.merge(m);
3124 }
3125 }
3126 }
3127
3128 res = pms.toArray();
3129 rd.publicMethods = res;
3130 return res;
3131 }
3132
3133
3134 //
3135 // Helpers for fetchers of one field, method, or constructor
3136 //
3137
3138 // This method does not copy the returned Field object!
3139 private static Field searchFields(Field[] fields, String name) {
3140 for (Field field : fields) {
3141 if (field.getName().equals(name)) {
3142 return field;
3143 }
3144 }
3145 return null;
3146 }
3147
3148 // Returns a "root" Field object. This Field object must NOT
3149 // be propagated to the outside world, but must instead be copied
3150 // via ReflectionFactory.copyField.
3151 private Field getField0(String name) {
3152 // Note: the intent is that the search algorithm this routine
3153 // uses be equivalent to the ordering imposed by
3154 // privateGetPublicFields(). It fetches only the declared
3155 // public fields for each class, however, to reduce the number
3156 // of Field objects which have to be created for the common
3157 // case where the field being requested is declared in the
3158 // class which is being queried.
3159 Field res;
3160 // Search declared public fields
3161 if ((res = searchFields(privateGetDeclaredFields(true), name)) != null) {
3162 return res;
3163 }
3164 // Direct superinterfaces, recursively
3165 Class<?>[] interfaces = getInterfaces(/* cloneArray */ false);
3166 for (Class<?> c : interfaces) {
3167 if ((res = c.getField0(name)) != null) {
3168 return res;
3169 }
3170 }
3171 // Direct superclass, recursively
3172 if (!isInterface()) {
3173 Class<?> c = getSuperclass();
3174 if (c != null) {
3175 if ((res = c.getField0(name)) != null) {
3176 return res;
3177 }
3178 }
3179 }
3180 return null;
3181 }
3182
3183 // This method does not copy the returned Method object!
3184 private static Method searchMethods(Method[] methods,
3185 String name,
3186 Class<?>[] parameterTypes)
3187 {
3188 ReflectionFactory fact = getReflectionFactory();
3189 Method res = null;
3190 for (Method m : methods) {
3191 if (m.getName().equals(name)
3192 && arrayContentsEq(parameterTypes,
3193 fact.getExecutableSharedParameterTypes(m))
3194 && (res == null
3195 || (res.getReturnType() != m.getReturnType()
3196 && res.getReturnType().isAssignableFrom(m.getReturnType()))))
3197 res = m;
3198 }
3199 return res;
3200 }
3201
3202 private static final Class<?>[] EMPTY_CLASS_ARRAY = new Class<?>[0];
3203
3204 // Returns a "root" Method object. This Method object must NOT
3205 // be propagated to the outside world, but must instead be copied
3206 // via ReflectionFactory.copyMethod.
3207 private Method getMethod0(String name, Class<?>[] parameterTypes) {
3208 PublicMethods.MethodList res = getMethodsRecursive(
3209 name,
3210 parameterTypes == null ? EMPTY_CLASS_ARRAY : parameterTypes,
3211 /* includeStatic */ true, /* publicOnly */ true);
3212 return res == null ? null : res.getMostSpecific();
3213 }
3214
3215 // Returns a list of "root" Method objects. These Method objects must NOT
3216 // be propagated to the outside world, but must instead be copied
3217 // via ReflectionFactory.copyMethod.
3218 private PublicMethods.MethodList getMethodsRecursive(String name,
3219 Class<?>[] parameterTypes,
3220 boolean includeStatic,
3221 boolean publicOnly) {
3222 // 1st check declared methods
3223 Method[] methods = privateGetDeclaredMethods(publicOnly);
3224 PublicMethods.MethodList res = PublicMethods.MethodList
3225 .filter(methods, name, parameterTypes, includeStatic);
3226 // if there is at least one match among declared methods, we need not
3227 // search any further as such match surely overrides matching methods
3228 // declared in superclass(es) or interface(s).
3229 if (res != null) {
3230 return res;
3231 }
3232
3233 // if there was no match among declared methods,
3234 // we must consult the superclass (if any) recursively...
3235 Class<?> sc = getSuperclass();
3236 if (sc != null) {
3237 res = sc.getMethodsRecursive(name, parameterTypes, includeStatic, publicOnly);
3238 }
3239
3240 // ...and coalesce the superclass methods with methods obtained
3241 // from directly implemented interfaces excluding static methods...
3242 for (Class<?> intf : getInterfaces(/* cloneArray */ false)) {
3243 res = PublicMethods.MethodList.merge(
3244 res, intf.getMethodsRecursive(name, parameterTypes, /* includeStatic */ false, publicOnly));
3245 }
3246
3247 return res;
3248 }
3249
3250 // Returns a "root" Constructor object. This Constructor object must NOT
3251 // be propagated to the outside world, but must instead be copied
3252 // via ReflectionFactory.copyConstructor.
3253 private Constructor<T> getConstructor0(Class<?>[] parameterTypes,
3254 int which) throws NoSuchMethodException
3255 {
3256 ReflectionFactory fact = getReflectionFactory();
3257 Constructor<T>[] constructors = privateGetDeclaredConstructors((which == Member.PUBLIC));
3258 for (Constructor<T> constructor : constructors) {
3259 if (arrayContentsEq(parameterTypes,
3260 fact.getExecutableSharedParameterTypes(constructor))) {
3261 return constructor;
3262 }
3263 }
3264 throw new NoSuchMethodException(methodToString("<init>", parameterTypes));
3265 }
3266
3267 //
3268 // Other helpers and base implementation
3269 //
3270
3271 private static boolean arrayContentsEq(Object[] a1, Object[] a2) {
3272 if (a1 == null) {
3273 return a2 == null || a2.length == 0;
3274 }
3275
3276 if (a2 == null) {
3277 return a1.length == 0;
3278 }
3279
3280 if (a1.length != a2.length) {
3281 return false;
3282 }
3283
3284 for (int i = 0; i < a1.length; i++) {
3285 if (a1[i] != a2[i]) {
3286 return false;
3287 }
3288 }
3289
3290 return true;
3291 }
3292
3293 private static Field[] copyFields(Field[] arg) {
3294 Field[] out = new Field[arg.length];
3295 ReflectionFactory fact = getReflectionFactory();
3296 for (int i = 0; i < arg.length; i++) {
3297 out[i] = fact.copyField(arg[i]);
3298 }
3299 return out;
3300 }
3301
3302 private static Method[] copyMethods(Method[] arg) {
3303 Method[] out = new Method[arg.length];
3304 ReflectionFactory fact = getReflectionFactory();
3305 for (int i = 0; i < arg.length; i++) {
3306 out[i] = fact.copyMethod(arg[i]);
3307 }
3308 return out;
3309 }
3310
3311 private static <U> Constructor<U>[] copyConstructors(Constructor<U>[] arg) {
3312 Constructor<U>[] out = arg.clone();
3313 ReflectionFactory fact = getReflectionFactory();
3314 for (int i = 0; i < out.length; i++) {
3315 out[i] = fact.copyConstructor(out[i]);
3316 }
3317 return out;
3318 }
3319
3320 private native Field[] getDeclaredFields0(boolean publicOnly);
3321 private native Method[] getDeclaredMethods0(boolean publicOnly);
3322 private native Constructor<T>[] getDeclaredConstructors0(boolean publicOnly);
3323 private native Class<?>[] getDeclaredClasses0();
3324
3325 /*
3326 * Returns an array containing the components of the Record attribute,
3327 * or null if the attribute is not present.
3328 *
3329 * Note that this method returns non-null array on a class with
3330 * the Record attribute even if this class is not a record.
3331 */
3332 private native RecordComponent[] getRecordComponents0();
3333 private native boolean isRecord0();
3334
3335 /**
3336 * Helper method to get the method name from arguments.
3337 */
3338 private String methodToString(String name, Class<?>[] argTypes) {
3339 return getName() + '.' + name +
3340 ((argTypes == null || argTypes.length == 0) ?
3341 "()" :
3342 Arrays.stream(argTypes)
3343 .map(c -> c == null ? "null" : c.getName())
3344 .collect(Collectors.joining(",", "(", ")")));
3345 }
3346
3347 /** use serialVersionUID from JDK 1.1 for interoperability */
3348 @java.io.Serial
3349 private static final long serialVersionUID = 3206093459760846163L;
3350
3351
3352 /**
3353 * Class Class is special cased within the Serialization Stream Protocol.
3354 *
3355 * A Class instance is written initially into an ObjectOutputStream in the
3356 * following format:
3357 * <pre>
3358 * {@code TC_CLASS} ClassDescriptor
3359 * A ClassDescriptor is a special cased serialization of
3360 * a {@code java.io.ObjectStreamClass} instance.
3361 * </pre>
3362 * A new handle is generated for the initial time the class descriptor
3363 * is written into the stream. Future references to the class descriptor
3364 * are written as references to the initial class descriptor instance.
3365 *
3366 * @see java.io.ObjectStreamClass
3367 */
3368 @java.io.Serial
3369 private static final ObjectStreamField[] serialPersistentFields =
3370 new ObjectStreamField[0];
3371
3372
3373 /**
3374 * Returns the assertion status that would be assigned to this
3375 * class if it were to be initialized at the time this method is invoked.
3376 * If this class has had its assertion status set, the most recent
3377 * setting will be returned; otherwise, if any package default assertion
3378 * status pertains to this class, the most recent setting for the most
3379 * specific pertinent package default assertion status is returned;
3380 * otherwise, if this class is not a system class (i.e., it has a
3381 * class loader) its class loader's default assertion status is returned;
3382 * otherwise, the system class default assertion status is returned.
3383 *
3384 * @apiNote
3385 * Few programmers will have any need for this method; it is provided
3386 * for the benefit of the JDK itself. (It allows a class to determine at
3387 * the time that it is initialized whether assertions should be enabled.)
3388 * Note that this method is not guaranteed to return the actual
3389 * assertion status that was (or will be) associated with the specified
3390 * class when it was (or will be) initialized.
3391 *
3392 * @return the desired assertion status of the specified class.
3393 * @see java.lang.ClassLoader#setClassAssertionStatus
3394 * @see java.lang.ClassLoader#setPackageAssertionStatus
3395 * @see java.lang.ClassLoader#setDefaultAssertionStatus
3396 * @since 1.4
3397 */
3398 public boolean desiredAssertionStatus() {
3399 ClassLoader loader = classLoader;
3400 // If the loader is null this is a system class, so ask the VM
3401 if (loader == null)
3402 return desiredAssertionStatus0(this);
3403
3404 // If the classloader has been initialized with the assertion
3405 // directives, ask it. Otherwise, ask the VM.
3406 synchronized(loader.assertionLock) {
3407 if (loader.classAssertionStatus != null) {
3408 return loader.desiredAssertionStatus(getName());
3409 }
3410 }
3411 return desiredAssertionStatus0(this);
3412 }
3413
3414 // Retrieves the desired assertion status of this class from the VM
3415 private static native boolean desiredAssertionStatus0(Class<?> clazz);
3416
3417 /**
3418 * Returns true if and only if this class was declared as an enum in the
3419 * source code.
3420 *
3421 * Note that {@link java.lang.Enum} is not itself an enum class.
3422 *
3423 * Also note that if an enum constant is declared with a class body,
3424 * the class of that enum constant object is an anonymous class
3425 * and <em>not</em> the class of the declaring enum class. The
3426 * {@link Enum#getDeclaringClass} method of an enum constant can
3427 * be used to get the class of the enum class declaring the
3428 * constant.
3429 *
3430 * @return true if and only if this class was declared as an enum in the
3431 * source code
3432 * @since 1.5
3433 * @jls 8.9.1 Enum Constants
3434 */
3435 public boolean isEnum() {
3436 // An enum must both directly extend java.lang.Enum and have
3437 // the ENUM bit set; classes for specialized enum constants
3438 // don't do the former.
3439 return (this.getModifiers() & ENUM) != 0 &&
3440 this.getSuperclass() == java.lang.Enum.class;
3441 }
3442
3443 /**
3444 * Returns {@code true} if and only if this class is a record class.
3445 *
3446 * <p> The {@linkplain #getSuperclass() direct superclass} of a record
3447 * class is {@code java.lang.Record}. A record class is {@linkplain
3448 * Modifier#FINAL final}. A record class has (possibly zero) record
3449 * components; {@link #getRecordComponents()} returns a non-null but
3450 * possibly empty value for a record.
3451 *
3452 * <p> Note that class {@link Record} is not a record class and thus
3453 * invoking this method on class {@code Record} returns {@code false}.
3454 *
3455 * @return true if and only if this class is a record class, otherwise false
3456 * @jls 8.10 Record Classes
3457 * @since 16
3458 */
3459 public boolean isRecord() {
3460 // this superclass and final modifier check is not strictly necessary
3461 // they are intrinsified and serve as a fast-path check
3462 return getSuperclass() == java.lang.Record.class &&
3463 (this.getModifiers() & Modifier.FINAL) != 0 &&
3464 isRecord0();
3465 }
3466
3467 // Fetches the factory for reflective objects
3468 private static ReflectionFactory getReflectionFactory() {
3469 var factory = reflectionFactory;
3470 if (factory != null) {
3471 return factory;
3472 }
3473 return reflectionFactory = ReflectionFactory.getReflectionFactory();
3474 }
3475 private static ReflectionFactory reflectionFactory;
3476
3477 /**
3478 * When CDS is enabled, the Class class may be aot-initialized. However,
3479 * we can't archive reflectionFactory, so we reset it to null, so it
3480 * will be allocated again at runtime.
3481 */
3482 private static void resetArchivedStates() {
3483 reflectionFactory = null;
3484 }
3485
3486 /**
3487 * Returns the elements of this enum class or null if this
3488 * Class object does not represent an enum class.
3489 *
3490 * @return an array containing the values comprising the enum class
3491 * represented by this {@code Class} object in the order they're
3492 * declared, or null if this {@code Class} object does not
3493 * represent an enum class
3494 * @since 1.5
3495 * @jls 8.9.1 Enum Constants
3496 */
3497 public T[] getEnumConstants() {
3498 T[] values = getEnumConstantsShared();
3499 return (values != null) ? values.clone() : null;
3500 }
3501
3502 /**
3503 * Returns the elements of this enum class or null if this
3504 * Class object does not represent an enum class;
3505 * identical to getEnumConstants except that the result is
3506 * uncloned, cached, and shared by all callers.
3507 */
3508 T[] getEnumConstantsShared() {
3509 T[] constants = enumConstants;
3510 if (constants == null) {
3511 if (!isEnum()) return null;
3512 try {
3513 final Method values = getMethod("values");
3514 values.setAccessible(true);
3515 @SuppressWarnings("unchecked")
3516 T[] temporaryConstants = (T[])values.invoke(null);
3517 enumConstants = constants = temporaryConstants;
3518 }
3519 // These can happen when users concoct enum-like classes
3520 // that don't comply with the enum spec.
3521 catch (InvocationTargetException | NoSuchMethodException |
3522 IllegalAccessException | NullPointerException |
3523 ClassCastException ex) { return null; }
3524 }
3525 return constants;
3526 }
3527 private transient volatile T[] enumConstants;
3528
3529 /**
3530 * Returns a map from simple name to enum constant. This package-private
3531 * method is used internally by Enum to implement
3532 * {@code public static <T extends Enum<T>> T valueOf(Class<T>, String)}
3533 * efficiently. Note that the map is returned by this method is
3534 * created lazily on first use. Typically it won't ever get created.
3535 */
3536 Map<String, T> enumConstantDirectory() {
3537 Map<String, T> directory = enumConstantDirectory;
3538 if (directory == null) {
3539 T[] universe = getEnumConstantsShared();
3540 if (universe == null)
3541 throw new IllegalArgumentException(
3542 getName() + " is not an enum class");
3543 directory = HashMap.newHashMap(universe.length);
3544 for (T constant : universe) {
3545 directory.put(((Enum<?>)constant).name(), constant);
3546 }
3547 enumConstantDirectory = directory;
3548 }
3549 return directory;
3550 }
3551 private transient volatile Map<String, T> enumConstantDirectory;
3552
3553 /**
3554 * Casts an object to the class or interface represented
3555 * by this {@code Class} object.
3556 *
3557 * @param obj the object to be cast
3558 * @return the object after casting, or null if obj is null
3559 *
3560 * @throws ClassCastException if the object is not
3561 * null and is not assignable to the type T.
3562 *
3563 * @since 1.5
3564 */
3565 @SuppressWarnings("unchecked")
3566 @IntrinsicCandidate
3567 public T cast(Object obj) {
3568 if (obj != null && !isInstance(obj))
3569 throw new ClassCastException(cannotCastMsg(obj));
3570 return (T) obj;
3571 }
3572
3573 private String cannotCastMsg(Object obj) {
3574 return "Cannot cast " + obj.getClass().getName() + " to " + getName();
3575 }
3576
3577 /**
3578 * Casts this {@code Class} object to represent a subclass of the class
3579 * represented by the specified class object. Checks that the cast
3580 * is valid, and throws a {@code ClassCastException} if it is not. If
3581 * this method succeeds, it always returns a reference to this {@code Class} object.
3582 *
3583 * <p>This method is useful when a client needs to "narrow" the type of
3584 * a {@code Class} object to pass it to an API that restricts the
3585 * {@code Class} objects that it is willing to accept. A cast would
3586 * generate a compile-time warning, as the correctness of the cast
3587 * could not be checked at runtime (because generic types are implemented
3588 * by erasure).
3589 *
3590 * @param <U> the type to cast this {@code Class} object to
3591 * @param clazz the class of the type to cast this {@code Class} object to
3592 * @return this {@code Class} object, cast to represent a subclass of
3593 * the specified class object.
3594 * @throws ClassCastException if this {@code Class} object does not
3595 * represent a subclass of the specified class (here "subclass" includes
3596 * the class itself).
3597 * @since 1.5
3598 */
3599 @SuppressWarnings("unchecked")
3600 public <U> Class<? extends U> asSubclass(Class<U> clazz) {
3601 if (clazz.isAssignableFrom(this))
3602 return (Class<? extends U>) this;
3603 else
3604 throw new ClassCastException(this.toString());
3605 }
3606
3607 /**
3608 * {@inheritDoc}
3609 * <p>Note that any annotation returned by this method is a
3610 * declaration annotation.
3611 *
3612 * @throws NullPointerException {@inheritDoc}
3613 * @since 1.5
3614 */
3615 @Override
3616 @SuppressWarnings("unchecked")
3617 public <A extends Annotation> A getAnnotation(Class<A> annotationClass) {
3618 Objects.requireNonNull(annotationClass);
3619
3620 return (A) annotationData().annotations.get(annotationClass);
3621 }
3622
3623 /**
3624 * {@inheritDoc}
3625 * @throws NullPointerException {@inheritDoc}
3626 * @since 1.5
3627 */
3628 @Override
3629 public boolean isAnnotationPresent(Class<? extends Annotation> annotationClass) {
3630 return GenericDeclaration.super.isAnnotationPresent(annotationClass);
3631 }
3632
3633 /**
3634 * {@inheritDoc}
3635 * <p>Note that any annotations returned by this method are
3636 * declaration annotations.
3637 *
3638 * @throws NullPointerException {@inheritDoc}
3639 * @since 1.8
3640 */
3641 @Override
3642 public <A extends Annotation> A[] getAnnotationsByType(Class<A> annotationClass) {
3643 Objects.requireNonNull(annotationClass);
3644
3645 AnnotationData annotationData = annotationData();
3646 return AnnotationSupport.getAssociatedAnnotations(annotationData.declaredAnnotations,
3647 this,
3648 annotationClass);
3649 }
3650
3651 /**
3652 * {@inheritDoc}
3653 * <p>Note that any annotations returned by this method are
3654 * declaration annotations.
3655 *
3656 * @since 1.5
3657 */
3658 @Override
3659 public Annotation[] getAnnotations() {
3660 return AnnotationParser.toArray(annotationData().annotations);
3661 }
3662
3663 /**
3664 * {@inheritDoc}
3665 * <p>Note that any annotation returned by this method is a
3666 * declaration annotation.
3667 *
3668 * @throws NullPointerException {@inheritDoc}
3669 * @since 1.8
3670 */
3671 @Override
3672 @SuppressWarnings("unchecked")
3673 public <A extends Annotation> A getDeclaredAnnotation(Class<A> annotationClass) {
3674 Objects.requireNonNull(annotationClass);
3675
3676 return (A) annotationData().declaredAnnotations.get(annotationClass);
3677 }
3678
3679 /**
3680 * {@inheritDoc}
3681 * <p>Note that any annotations returned by this method are
3682 * declaration annotations.
3683 *
3684 * @throws NullPointerException {@inheritDoc}
3685 * @since 1.8
3686 */
3687 @Override
3688 public <A extends Annotation> A[] getDeclaredAnnotationsByType(Class<A> annotationClass) {
3689 Objects.requireNonNull(annotationClass);
3690
3691 return AnnotationSupport.getDirectlyAndIndirectlyPresent(annotationData().declaredAnnotations,
3692 annotationClass);
3693 }
3694
3695 /**
3696 * {@inheritDoc}
3697 * <p>Note that any annotations returned by this method are
3698 * declaration annotations.
3699 *
3700 * @since 1.5
3701 */
3702 @Override
3703 public Annotation[] getDeclaredAnnotations() {
3704 return AnnotationParser.toArray(annotationData().declaredAnnotations);
3705 }
3706
3707 // annotation data that might get invalidated when JVM TI RedefineClasses() is called
3708 private static class AnnotationData {
3709 final Map<Class<? extends Annotation>, Annotation> annotations;
3710 final Map<Class<? extends Annotation>, Annotation> declaredAnnotations;
3711
3712 // Value of classRedefinedCount when we created this AnnotationData instance
3713 final int redefinedCount;
3714
3715 AnnotationData(Map<Class<? extends Annotation>, Annotation> annotations,
3716 Map<Class<? extends Annotation>, Annotation> declaredAnnotations,
3717 int redefinedCount) {
3718 this.annotations = annotations;
3719 this.declaredAnnotations = declaredAnnotations;
3720 this.redefinedCount = redefinedCount;
3721 }
3722 }
3723
3724 // Annotations cache
3725 @SuppressWarnings("UnusedDeclaration")
3726 private transient volatile AnnotationData annotationData;
3727
3728 private AnnotationData annotationData() {
3729 while (true) { // retry loop
3730 AnnotationData annotationData = this.annotationData;
3731 int classRedefinedCount = this.classRedefinedCount;
3732 if (annotationData != null &&
3733 annotationData.redefinedCount == classRedefinedCount) {
3734 return annotationData;
3735 }
3736 // null or stale annotationData -> optimistically create new instance
3737 AnnotationData newAnnotationData = createAnnotationData(classRedefinedCount);
3738 // try to install it
3739 if (Atomic.casAnnotationData(this, annotationData, newAnnotationData)) {
3740 // successfully installed new AnnotationData
3741 return newAnnotationData;
3742 }
3743 }
3744 }
3745
3746 private AnnotationData createAnnotationData(int classRedefinedCount) {
3747 Map<Class<? extends Annotation>, Annotation> declaredAnnotations =
3748 AnnotationParser.parseAnnotations(getRawAnnotations(), getConstantPool(), this);
3749 Class<?> superClass = getSuperclass();
3750 Map<Class<? extends Annotation>, Annotation> annotations = null;
3751 if (superClass != null) {
3752 Map<Class<? extends Annotation>, Annotation> superAnnotations =
3753 superClass.annotationData().annotations;
3754 for (Map.Entry<Class<? extends Annotation>, Annotation> e : superAnnotations.entrySet()) {
3755 Class<? extends Annotation> annotationClass = e.getKey();
3756 if (AnnotationType.getInstance(annotationClass).isInherited()) {
3757 if (annotations == null) { // lazy construction
3758 annotations = LinkedHashMap.newLinkedHashMap(Math.max(
3759 declaredAnnotations.size(),
3760 Math.min(12, declaredAnnotations.size() + superAnnotations.size())
3761 )
3762 );
3763 }
3764 annotations.put(annotationClass, e.getValue());
3765 }
3766 }
3767 }
3768 if (annotations == null) {
3769 // no inherited annotations -> share the Map with declaredAnnotations
3770 annotations = declaredAnnotations;
3771 } else {
3772 // at least one inherited annotation -> declared may override inherited
3773 annotations.putAll(declaredAnnotations);
3774 }
3775 return new AnnotationData(annotations, declaredAnnotations, classRedefinedCount);
3776 }
3777
3778 // Annotation interfaces cache their internal (AnnotationType) form
3779
3780 @SuppressWarnings("UnusedDeclaration")
3781 private transient volatile AnnotationType annotationType;
3782
3783 boolean casAnnotationType(AnnotationType oldType, AnnotationType newType) {
3784 return Atomic.casAnnotationType(this, oldType, newType);
3785 }
3786
3787 AnnotationType getAnnotationType() {
3788 return annotationType;
3789 }
3790
3791 Map<Class<? extends Annotation>, Annotation> getDeclaredAnnotationMap() {
3792 return annotationData().declaredAnnotations;
3793 }
3794
3795 /* Backing store of user-defined values pertaining to this class.
3796 * Maintained by the ClassValue class.
3797 */
3798 transient ClassValue.ClassValueMap classValueMap;
3799
3800 /**
3801 * Returns an {@code AnnotatedType} object that represents the use of a
3802 * type to specify the superclass of the entity represented by this {@code
3803 * Class} object. (The <em>use</em> of type Foo to specify the superclass
3804 * in '... extends Foo' is distinct from the <em>declaration</em> of class
3805 * Foo.)
3806 *
3807 * <p> If this {@code Class} object represents a class whose declaration
3808 * does not explicitly indicate an annotated superclass, then the return
3809 * value is an {@code AnnotatedType} object representing an element with no
3810 * annotations.
3811 *
3812 * <p> If this {@code Class} represents either the {@code Object} class, an
3813 * interface type, an array type, a primitive type, or void, the return
3814 * value is {@code null}.
3815 *
3816 * @return an object representing the superclass
3817 * @since 1.8
3818 */
3819 public AnnotatedType getAnnotatedSuperclass() {
3820 if (this == Object.class ||
3821 isInterface() ||
3822 isArray() ||
3823 isPrimitive() ||
3824 this == Void.TYPE) {
3825 return null;
3826 }
3827
3828 return TypeAnnotationParser.buildAnnotatedSuperclass(getRawTypeAnnotations(), getConstantPool(), this);
3829 }
3830
3831 /**
3832 * Returns an array of {@code AnnotatedType} objects that represent the use
3833 * of types to specify superinterfaces of the entity represented by this
3834 * {@code Class} object. (The <em>use</em> of type Foo to specify a
3835 * superinterface in '... implements Foo' is distinct from the
3836 * <em>declaration</em> of interface Foo.)
3837 *
3838 * <p> If this {@code Class} object represents a class, the return value is
3839 * an array containing objects representing the uses of interface types to
3840 * specify interfaces implemented by the class. The order of the objects in
3841 * the array corresponds to the order of the interface types used in the
3842 * 'implements' clause of the declaration of this {@code Class} object.
3843 *
3844 * <p> If this {@code Class} object represents an interface, the return
3845 * value is an array containing objects representing the uses of interface
3846 * types to specify interfaces directly extended by the interface. The
3847 * order of the objects in the array corresponds to the order of the
3848 * interface types used in the 'extends' clause of the declaration of this
3849 * {@code Class} object.
3850 *
3851 * <p> If this {@code Class} object represents a class or interface whose
3852 * declaration does not explicitly indicate any annotated superinterfaces,
3853 * the return value is an array of length 0.
3854 *
3855 * <p> If this {@code Class} object represents either the {@code Object}
3856 * class, an array type, a primitive type, or void, the return value is an
3857 * array of length 0.
3858 *
3859 * @return an array representing the superinterfaces
3860 * @since 1.8
3861 */
3862 public AnnotatedType[] getAnnotatedInterfaces() {
3863 return TypeAnnotationParser.buildAnnotatedInterfaces(getRawTypeAnnotations(), getConstantPool(), this);
3864 }
3865
3866 private native Class<?> getNestHost0();
3867
3868 /**
3869 * Returns the nest host of the <a href=#nest>nest</a> to which the class
3870 * or interface represented by this {@code Class} object belongs.
3871 * Every class and interface belongs to exactly one nest.
3872 *
3873 * If the nest host of this class or interface has previously
3874 * been determined, then this method returns the nest host.
3875 * If the nest host of this class or interface has
3876 * not previously been determined, then this method determines the nest
3877 * host using the algorithm of JVMS 5.4.4, and returns it.
3878 *
3879 * Often, a class or interface belongs to a nest consisting only of itself,
3880 * in which case this method returns {@code this} to indicate that the class
3881 * or interface is the nest host.
3882 *
3883 * <p>If this {@code Class} object represents a primitive type, an array type,
3884 * or {@code void}, then this method returns {@code this},
3885 * indicating that the represented entity belongs to the nest consisting only of
3886 * itself, and is the nest host.
3887 *
3888 * @return the nest host of this class or interface
3889 *
3890 * @since 11
3891 * @jvms 4.7.28 The {@code NestHost} Attribute
3892 * @jvms 4.7.29 The {@code NestMembers} Attribute
3893 * @jvms 5.4.4 Access Control
3894 */
3895 public Class<?> getNestHost() {
3896 if (isPrimitive() || isArray()) {
3897 return this;
3898 }
3899 return getNestHost0();
3900 }
3901
3902 /**
3903 * Determines if the given {@code Class} is a nestmate of the
3904 * class or interface represented by this {@code Class} object.
3905 * Two classes or interfaces are nestmates
3906 * if they have the same {@linkplain #getNestHost() nest host}.
3907 *
3908 * @param c the class to check
3909 * @return {@code true} if this class and {@code c} are members of
3910 * the same nest; and {@code false} otherwise.
3911 *
3912 * @since 11
3913 */
3914 public boolean isNestmateOf(Class<?> c) {
3915 if (this == c) {
3916 return true;
3917 }
3918 if (isPrimitive() || isArray() ||
3919 c.isPrimitive() || c.isArray()) {
3920 return false;
3921 }
3922
3923 return getNestHost() == c.getNestHost();
3924 }
3925
3926 private native Class<?>[] getNestMembers0();
3927
3928 /**
3929 * Returns an array containing {@code Class} objects representing all the
3930 * classes and interfaces that are members of the nest to which the class
3931 * or interface represented by this {@code Class} object belongs.
3932 *
3933 * First, this method obtains the {@linkplain #getNestHost() nest host},
3934 * {@code H}, of the nest to which the class or interface represented by
3935 * this {@code Class} object belongs. The zeroth element of the returned
3936 * array is {@code H}.
3937 *
3938 * Then, for each class or interface {@code C} which is recorded by {@code H}
3939 * as being a member of its nest, this method attempts to obtain the {@code Class}
3940 * object for {@code C} (using {@linkplain #getClassLoader() the defining class
3941 * loader} of the current {@code Class} object), and then obtains the
3942 * {@linkplain #getNestHost() nest host} of the nest to which {@code C} belongs.
3943 * The classes and interfaces which are recorded by {@code H} as being members
3944 * of its nest, and for which {@code H} can be determined as their nest host,
3945 * are indicated by subsequent elements of the returned array. The order of
3946 * such elements is unspecified. Duplicates are permitted.
3947 *
3948 * <p>If this {@code Class} object represents a primitive type, an array type,
3949 * or {@code void}, then this method returns a single-element array containing
3950 * {@code this}.
3951 *
3952 * @apiNote
3953 * The returned array includes only the nest members recorded in the {@code NestMembers}
3954 * attribute, and not any hidden classes that were added to the nest via
3955 * {@link MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
3956 * Lookup::defineHiddenClass}.
3957 *
3958 * @return an array of all classes and interfaces in the same nest as
3959 * this class or interface
3960 *
3961 * @since 11
3962 * @see #getNestHost()
3963 * @jvms 4.7.28 The {@code NestHost} Attribute
3964 * @jvms 4.7.29 The {@code NestMembers} Attribute
3965 */
3966 public Class<?>[] getNestMembers() {
3967 if (isPrimitive() || isArray()) {
3968 return new Class<?>[] { this };
3969 }
3970 Class<?>[] members = getNestMembers0();
3971 // Can't actually enable this due to bootstrapping issues
3972 // assert(members.length != 1 || members[0] == this); // expected invariant from VM
3973 return members;
3974 }
3975
3976 /**
3977 * Returns the descriptor string of the entity (class, interface, array class,
3978 * primitive type, or {@code void}) represented by this {@code Class} object.
3979 *
3980 * <p> If this {@code Class} object represents a class or interface,
3981 * not an array class, then:
3982 * <ul>
3983 * <li> If the class or interface is not {@linkplain Class#isHidden() hidden},
3984 * then the result is a field descriptor (JVMS {@jvms 4.3.2})
3985 * for the class or interface. Calling
3986 * {@link ClassDesc#ofDescriptor(String) ClassDesc::ofDescriptor}
3987 * with the result descriptor string produces a {@link ClassDesc ClassDesc}
3988 * describing this class or interface.
3989 * <li> If the class or interface is {@linkplain Class#isHidden() hidden},
3990 * then the result is a string of the form:
3991 * <blockquote>
3992 * {@code "L" +} <em>N</em> {@code + "." + <suffix> + ";"}
3993 * </blockquote>
3994 * where <em>N</em> is the {@linkplain ClassLoader##binary-name binary name}
3995 * encoded in internal form indicated by the {@code class} file passed to
3996 * {@link MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
3997 * Lookup::defineHiddenClass}, and {@code <suffix>} is an unqualified name.
3998 * A hidden class or interface has no {@linkplain ClassDesc nominal descriptor}.
3999 * The result string is not a type descriptor.
4000 * </ul>
4001 *
4002 * <p> If this {@code Class} object represents an array class, then
4003 * the result is a string consisting of one or more '{@code [}' characters
4004 * representing the depth of the array nesting, followed by the
4005 * descriptor string of the element type.
4006 * <ul>
4007 * <li> If the element type is not a {@linkplain Class#isHidden() hidden} class
4008 * or interface, then this array class can be described nominally.
4009 * Calling {@link ClassDesc#ofDescriptor(String) ClassDesc::ofDescriptor}
4010 * with the result descriptor string produces a {@link ClassDesc ClassDesc}
4011 * describing this array class.
4012 * <li> If the element type is a {@linkplain Class#isHidden() hidden} class or
4013 * interface, then this array class cannot be described nominally.
4014 * The result string is not a type descriptor.
4015 * </ul>
4016 *
4017 * <p> If this {@code Class} object represents a primitive type or
4018 * {@code void}, then the result is a field descriptor string which
4019 * is a one-letter code corresponding to a primitive type or {@code void}
4020 * ({@code "B", "C", "D", "F", "I", "J", "S", "Z", "V"}) (JVMS {@jvms 4.3.2}).
4021 *
4022 * @return the descriptor string for this {@code Class} object
4023 * @jvms 4.3.2 Field Descriptors
4024 * @since 12
4025 */
4026 @Override
4027 public String descriptorString() {
4028 if (isPrimitive())
4029 return Wrapper.forPrimitiveType(this).basicTypeString();
4030
4031 if (isArray()) {
4032 return "[".concat(componentType.descriptorString());
4033 } else if (isHidden()) {
4034 String name = getName();
4035 int index = name.indexOf('/');
4036 return new StringBuilder(name.length() + 2)
4037 .append('L')
4038 .append(name.substring(0, index).replace('.', '/'))
4039 .append('.')
4040 .append(name, index + 1, name.length())
4041 .append(';')
4042 .toString();
4043 } else {
4044 String name = getName().replace('.', '/');
4045 return StringConcatHelper.concat("L", name, ";");
4046 }
4047 }
4048
4049 /**
4050 * Returns the component type of this {@code Class}, if it describes
4051 * an array type, or {@code null} otherwise.
4052 *
4053 * @implSpec
4054 * Equivalent to {@link Class#getComponentType()}.
4055 *
4056 * @return a {@code Class} describing the component type, or {@code null}
4057 * if this {@code Class} does not describe an array type
4058 * @since 12
4059 */
4060 @Override
4061 public Class<?> componentType() {
4062 return isArray() ? componentType : null;
4063 }
4064
4065 /**
4066 * Returns a {@code Class} for an array type whose component type
4067 * is described by this {@linkplain Class}.
4068 *
4069 * @throws UnsupportedOperationException if this component type is {@linkplain
4070 * Void#TYPE void} or if the number of dimensions of the resulting array
4071 * type would exceed 255.
4072 * @return a {@code Class} describing the array type
4073 * @jvms 4.3.2 Field Descriptors
4074 * @jvms 4.4.1 The {@code CONSTANT_Class_info} Structure
4075 * @since 12
4076 */
4077 @Override
4078 public Class<?> arrayType() {
4079 try {
4080 return Array.newInstance(this, 0).getClass();
4081 } catch (IllegalArgumentException iae) {
4082 throw new UnsupportedOperationException(iae);
4083 }
4084 }
4085
4086 /**
4087 * Returns a nominal descriptor for this instance, if one can be
4088 * constructed, or an empty {@link Optional} if one cannot be.
4089 *
4090 * @return An {@link Optional} containing the resulting nominal descriptor,
4091 * or an empty {@link Optional} if one cannot be constructed.
4092 * @since 12
4093 */
4094 @Override
4095 public Optional<ClassDesc> describeConstable() {
4096 Class<?> c = isArray() ? elementType() : this;
4097 return c.isHidden() ? Optional.empty()
4098 : Optional.of(ConstantUtils.classDesc(this));
4099 }
4100
4101 /**
4102 * Returns {@code true} if and only if the underlying class is a hidden class.
4103 *
4104 * @return {@code true} if and only if this class is a hidden class.
4105 *
4106 * @since 15
4107 * @see MethodHandles.Lookup#defineHiddenClass
4108 * @see Class##hiddenClasses Hidden Classes
4109 */
4110 @IntrinsicCandidate
4111 public native boolean isHidden();
4112
4113 /**
4114 * Returns an array containing {@code Class} objects representing the
4115 * direct subinterfaces or subclasses permitted to extend or
4116 * implement this class or interface if it is sealed. The order of such elements
4117 * is unspecified. The array is empty if this sealed class or interface has no
4118 * permitted subclass. If this {@code Class} object represents a primitive type,
4119 * {@code void}, an array type, or a class or interface that is not sealed,
4120 * that is {@link #isSealed()} returns {@code false}, then this method returns {@code null}.
4121 * Conversely, if {@link #isSealed()} returns {@code true}, then this method
4122 * returns a non-null value.
4123 *
4124 * For each class or interface {@code C} which is recorded as a permitted
4125 * direct subinterface or subclass of this class or interface,
4126 * this method attempts to obtain the {@code Class}
4127 * object for {@code C} (using {@linkplain #getClassLoader() the defining class
4128 * loader} of the current {@code Class} object).
4129 * The {@code Class} objects which can be obtained and which are direct
4130 * subinterfaces or subclasses of this class or interface,
4131 * are indicated by elements of the returned array. If a {@code Class} object
4132 * cannot be obtained, it is silently ignored, and not included in the result
4133 * array.
4134 *
4135 * @return an array of {@code Class} objects of the permitted subclasses of this class
4136 * or interface, or {@code null} if this class or interface is not sealed.
4137 *
4138 * @jls 8.1 Class Declarations
4139 * @jls 9.1 Interface Declarations
4140 * @since 17
4141 */
4142 public Class<?>[] getPermittedSubclasses() {
4143 Class<?>[] subClasses;
4144 if (isArray() || isPrimitive() || (subClasses = getPermittedSubclasses0()) == null) {
4145 return null;
4146 }
4147 if (subClasses.length > 0) {
4148 if (Arrays.stream(subClasses).anyMatch(c -> !isDirectSubType(c))) {
4149 subClasses = Arrays.stream(subClasses)
4150 .filter(this::isDirectSubType)
4151 .toArray(s -> new Class<?>[s]);
4152 }
4153 }
4154 return subClasses;
4155 }
4156
4157 private boolean isDirectSubType(Class<?> c) {
4158 if (isInterface()) {
4159 for (Class<?> i : c.getInterfaces(/* cloneArray */ false)) {
4160 if (i == this) {
4161 return true;
4162 }
4163 }
4164 } else {
4165 return c.getSuperclass() == this;
4166 }
4167 return false;
4168 }
4169
4170 /**
4171 * Returns {@code true} if and only if this {@code Class} object represents
4172 * a sealed class or interface. If this {@code Class} object represents a
4173 * primitive type, {@code void}, or an array type, this method returns
4174 * {@code false}. A sealed class or interface has (possibly zero) permitted
4175 * subclasses; {@link #getPermittedSubclasses()} returns a non-null but
4176 * possibly empty value for a sealed class or interface.
4177 *
4178 * @return {@code true} if and only if this {@code Class} object represents
4179 * a sealed class or interface.
4180 *
4181 * @jls 8.1 Class Declarations
4182 * @jls 9.1 Interface Declarations
4183 * @since 17
4184 */
4185 public boolean isSealed() {
4186 if (isArray() || isPrimitive()) {
4187 return false;
4188 }
4189 return getPermittedSubclasses() != null;
4190 }
4191
4192 private native Class<?>[] getPermittedSubclasses0();
4193
4194 /*
4195 * Return the class's major and minor class file version packed into an int.
4196 * The high order 16 bits contain the class's minor version. The low order
4197 * 16 bits contain the class's major version.
4198 *
4199 * If the class is an array type then the class file version of its element
4200 * type is returned. If the class is a primitive type then the latest class
4201 * file major version is returned and zero is returned for the minor version.
4202 */
4203 /* package-private */
4204 int getClassFileVersion() {
4205 Class<?> c = isArray() ? elementType() : this;
4206 return c.getClassFileVersion0();
4207 }
4208
4209 private native int getClassFileVersion0();
4210
4211 /*
4212 * Return the access flags as they were in the class's bytecode, including
4213 * the original setting of ACC_SUPER.
4214 *
4215 * If the class is an array type then the access flags of the element type is
4216 * returned. If the class is a primitive then ACC_ABSTRACT | ACC_FINAL | ACC_PUBLIC.
4217 */
4218 private int getClassAccessFlagsRaw() {
4219 Class<?> c = isArray() ? elementType() : this;
4220 return c.getClassAccessFlagsRaw0();
4221 }
4222
4223 private native int getClassAccessFlagsRaw0();
4224 }