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.HashSet;
65 import java.util.LinkedHashMap;
66 import java.util.LinkedHashSet;
67 import java.util.List;
68 import java.util.Map;
69 import java.util.Objects;
70 import java.util.Optional;
71 import java.util.Set;
72 import java.util.stream.Collectors;
73
74 import jdk.internal.constant.ConstantUtils;
75 import jdk.internal.javac.PreviewFeature;
76 import jdk.internal.loader.BootLoader;
77 import jdk.internal.loader.BuiltinClassLoader;
78 import jdk.internal.misc.PreviewFeatures;
79 import jdk.internal.misc.Unsafe;
80 import jdk.internal.module.Resources;
81 import jdk.internal.reflect.CallerSensitive;
82 import jdk.internal.reflect.CallerSensitiveAdapter;
83 import jdk.internal.reflect.ConstantPool;
84 import jdk.internal.reflect.Reflection;
85 import jdk.internal.reflect.ReflectionFactory;
86 import jdk.internal.vm.annotation.IntrinsicCandidate;
87 import jdk.internal.vm.annotation.Stable;
88
89 import sun.invoke.util.Wrapper;
90 import sun.reflect.generics.factory.CoreReflectionFactory;
91 import sun.reflect.generics.factory.GenericsFactory;
92 import sun.reflect.generics.repository.ClassRepository;
93 import sun.reflect.generics.repository.MethodRepository;
94 import sun.reflect.generics.repository.ConstructorRepository;
95 import sun.reflect.generics.scope.ClassScope;
96 import sun.reflect.annotation.*;
97
98 /**
99 * Instances of the class {@code Class} represent classes and
100 * interfaces in a running Java application. An enum class and a record
101 * class are kinds of class; an annotation interface is a kind of
102 * interface. Every array also belongs to a class that is reflected as
103 * a {@code Class} object that is shared by all arrays with the same
104 * element type and number of dimensions. The primitive Java types
105 * ({@code boolean}, {@code byte}, {@code char}, {@code short}, {@code
106 * int}, {@code long}, {@code float}, and {@code double}), and the
107 * keyword {@code void} are also represented as {@code Class} objects.
108 *
109 * <p> {@code Class} has no public constructor. Instead a {@code Class}
110 * object is constructed automatically by the Java Virtual Machine when
111 * a class is derived from the bytes of a {@code class} file through
112 * the invocation of one of the following methods:
113 * <ul>
114 * <li> {@link ClassLoader#defineClass(String, byte[], int, int) ClassLoader::defineClass}
115 * <li> {@link java.lang.invoke.MethodHandles.Lookup#defineClass(byte[])
116 * java.lang.invoke.MethodHandles.Lookup::defineClass}
117 * <li> {@link java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
118 * java.lang.invoke.MethodHandles.Lookup::defineHiddenClass}
119 * </ul>
120 *
121 * <p> The methods of class {@code Class} expose many characteristics of a
122 * class or interface. Most characteristics are derived from the {@code class}
123 * file that the class loader passed to the Java Virtual Machine or
124 * from the {@code class} file passed to {@code Lookup::defineClass}
125 * or {@code Lookup::defineHiddenClass}.
126 * A few characteristics are determined by the class loading environment
127 * at run time, such as the module returned by {@link #getModule() getModule()}.
128 *
129 * <p> The following example uses a {@code Class} object to print the
130 * class name of an object:
131 *
132 * {@snippet lang="java" :
133 * void printClassName(Object obj) {
134 * System.out.println("The class of " + obj +
135 * " is " + obj.getClass().getName());
136 * }}
137 *
138 * It is also possible to get the {@code Class} object for a named
139 * class or interface (or for {@code void}) using a <dfn>class literal</dfn>
140 * (JLS {@jls 15.8.2}).
141 * For example:
142 *
143 * {@snippet lang="java" :
144 * System.out.println("The name of class Foo is: " + Foo.class.getName()); // @highlight substring="Foo.class"
145 * }
146 *
147 * <p> Some methods of class {@code Class} expose whether the declaration of
148 * a class or interface in Java source code was <em>enclosed</em> within
149 * another declaration. Other methods describe how a class or interface
150 * is situated in a <dfn>{@index "nest"}</dfn>. A nest is a set of
151 * classes and interfaces, in the same run-time package, that
152 * allow mutual access to their {@code private} members.
153 * The classes and interfaces are known as <dfn>{@index "nestmates"}</dfn>
154 * (JVMS {@jvms 4.7.29}).
155 * One nestmate acts as the
156 * <dfn>nest host</dfn> (JVMS {@jvms 4.7.28}), and enumerates the other nestmates which
157 * belong to the nest; each of them in turn records it as the nest host.
158 * The classes and interfaces which belong to a nest, including its host, are
159 * determined when
160 * {@code class} files are generated, for example, a Java compiler
161 * will typically record a top-level class as the host of a nest where the
162 * other members are the classes and interfaces whose declarations are
163 * enclosed within the top-level class declaration.
164 *
165 * <h2><a id=hiddenClasses>Hidden Classes</a></h2>
166 * A class or interface created by the invocation of
167 * {@link java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
168 * Lookup::defineHiddenClass} is a {@linkplain Class#isHidden() <dfn>hidden</dfn>}
169 * class or interface.
170 * All kinds of class, including enum classes and record classes, may be
171 * hidden classes; all kinds of interface, including annotation interfaces,
172 * may be hidden interfaces.
173 *
174 * The {@linkplain #getName() name of a hidden class or interface} is
175 * not a {@linkplain ClassLoader##binary-name binary name},
176 * which means the following:
177 * <ul>
178 * <li>A hidden class or interface cannot be referenced by the constant pools
179 * of other classes and interfaces.
180 * <li>A hidden class or interface cannot be described in
181 * {@linkplain java.lang.constant.ConstantDesc <em>nominal form</em>} by
182 * {@link #describeConstable() Class::describeConstable},
183 * {@link ClassDesc#of(String) ClassDesc::of}, or
184 * {@link ClassDesc#ofDescriptor(String) ClassDesc::ofDescriptor}.
185 * <li>A hidden class or interface cannot be discovered by {@link #forName Class::forName}
186 * or {@link ClassLoader#loadClass(String, boolean) ClassLoader::loadClass}.
187 * </ul>
188 *
189 * A hidden class or interface is never an array class, but may be
190 * the element type of an array. In all other respects, the fact that
191 * a class or interface is hidden has no bearing on the characteristics
192 * exposed by the methods of class {@code Class}.
193 *
194 * <h2><a id=implicitClasses>Implicitly Declared Classes</a></h2>
195 *
196 * Conventionally, a Java compiler, starting from a source file for an
197 * implicitly declared class, say {@code HelloWorld.java}, creates a
198 * similarly-named {@code class} file, {@code HelloWorld.class}, where
199 * the class stored in that {@code class} file is named {@code
200 * "HelloWorld"}, matching the base names of the source and {@code
201 * class} files.
202 *
203 * For the {@code Class} object of an implicitly declared class {@code
204 * HelloWorld}, the methods to get the {@linkplain #getName name} and
205 * {@linkplain #getTypeName type name} return results
206 * equal to {@code "HelloWorld"}. The {@linkplain #getSimpleName
207 * simple name} of such an implicitly declared class is {@code "HelloWorld"} and
208 * the {@linkplain #getCanonicalName canonical name} is {@code "HelloWorld"}.
209 *
210 * @param <T> the type of the class modeled by this {@code Class}
211 * object. For example, the type of {@code String.class} is {@code
212 * Class<String>}. Use {@code Class<?>} if the class being modeled is
213 * unknown.
214 *
215 * @see java.lang.ClassLoader#defineClass(byte[], int, int)
216 * @since 1.0
217 */
218 public final class Class<T> implements java.io.Serializable,
219 GenericDeclaration,
220 Type,
221 AnnotatedElement,
222 TypeDescriptor.OfField<Class<?>>,
223 Constable {
224 private static final int ANNOTATION = 0x00002000;
225 private static final int ENUM = 0x00004000;
226 private static final int SYNTHETIC = 0x00001000;
227
228 private static native void registerNatives();
229 static {
230 runtimeSetup();
231 }
232
233 // Called from JVM when loading an AOT cache
234 private static void runtimeSetup() {
235 registerNatives();
236 }
237
238 /*
239 * Private constructor. Only the Java Virtual Machine creates Class objects.
240 * This constructor is not used and prevents the default constructor being
241 * generated.
242 */
243 private Class(ClassLoader loader, Class<?> arrayComponentType, char mods, ProtectionDomain pd, boolean isPrim) {
244 // Initialize final field for classLoader. The initialization value of non-null
245 // prevents future JIT optimizations from assuming this final field is null.
246 // The following assignments are done directly by the VM without calling this constructor.
247 classLoader = loader;
248 componentType = arrayComponentType;
249 modifiers = mods;
250 protectionDomain = pd;
251 primitive = isPrim;
252 }
253
254 /**
255 * Converts the object to a string. The string representation is the
256 * string "class" or "interface", followed by a space, and then by the
257 * name of the class in the format returned by {@code getName}.
258 * If this {@code Class} object represents a primitive type,
259 * this method returns the name of the primitive type. If
260 * this {@code Class} object represents void this method returns
261 * "void". If this {@code Class} object represents an array type,
262 * this method returns "class " followed by {@code getName}.
263 *
264 * @return a string representation of this {@code Class} object.
265 */
266 public String toString() {
267 String kind = isInterface() ? "interface " : isPrimitive() ? "" : "class ";
268 return kind.concat(getName());
269 }
270
271 /**
272 * Returns a string describing this {@code Class}, including
273 * information about modifiers, {@link #isSealed() sealed}/{@code
274 * non-sealed} status, and type parameters.
275 *
276 * The string is formatted as a list of type modifiers, if any,
277 * followed by the kind of type (empty string for primitive types
278 * and {@code class}, {@code enum}, {@code interface},
279 * {@code @interface}, or {@code record} as appropriate), followed
280 * by the type's name, followed by an angle-bracketed
281 * comma-separated list of the type's type parameters, if any,
282 * including informative bounds on the type parameters, if any.
283 *
284 * A space is used to separate modifiers from one another and to
285 * separate any modifiers from the kind of type. The modifiers
286 * occur in canonical order. If there are no type parameters, the
287 * type parameter list is elided.
288 *
289 * For an array type, the string starts with the type name,
290 * followed by an angle-bracketed comma-separated list of the
291 * type's type parameters, if any, followed by a sequence of
292 * {@code []} characters, one set of brackets per dimension of
293 * the array.
294 *
295 * <p>Note that since information about the runtime representation
296 * of a type is being generated, modifiers not present on the
297 * originating source code or illegal on the originating source
298 * code may be present.
299 *
300 * @return a string describing this {@code Class}, including
301 * information about modifiers and type parameters
302 *
303 * @since 1.8
304 */
305 public String toGenericString() {
306 if (isPrimitive()) {
307 return toString();
308 } else {
309 StringBuilder sb = new StringBuilder();
310 Class<?> component = this;
311 int arrayDepth = 0;
312
313 if (isArray()) {
314 do {
315 arrayDepth++;
316 component = component.getComponentType();
317 } while (component.isArray());
318 sb.append(component.getName());
319 } else {
320 // Class modifiers are a superset of interface modifiers
321 int modifiers = getModifiers() & Modifier.classModifiers();
322 // Modifier.toString() below mis-interprets SYNCHRONIZED, STRICT, and VOLATILE bits
323 modifiers &= ~(Modifier.SYNCHRONIZED | Modifier.STRICT | Modifier.VOLATILE);
324 if (modifiers != 0) {
325 sb.append(Modifier.toString(modifiers));
326 sb.append(' ');
327 }
328
329 // A class cannot be strictfp and sealed/non-sealed so
330 // it is sufficient to check for sealed-ness after all
331 // modifiers are printed.
332 addSealingInfo(modifiers, sb);
333
334 if (isAnnotation()) {
335 sb.append('@');
336 }
337 if (isInterface()) { // Note: all annotation interfaces are interfaces
338 sb.append("interface");
339 } else {
340 if (isEnum())
341 sb.append("enum");
342 else {
343 if (isValue()) {
344 sb.append("value ");
345 }
346 if (isRecord())
347 sb.append("record");
348 else
349 sb.append("class");
350 }
351 }
352 sb.append(' ');
353 sb.append(getName());
354 }
355
356 TypeVariable<?>[] typeparms = component.getTypeParameters();
357 if (typeparms.length > 0) {
358 sb.append(Arrays.stream(typeparms)
359 .map(Class::typeVarBounds)
360 .collect(Collectors.joining(",", "<", ">")));
361 }
362
363 if (arrayDepth > 0) sb.append("[]".repeat(arrayDepth));
364
365 return sb.toString();
366 }
367 }
368
369 private void addSealingInfo(int modifiers, StringBuilder sb) {
370 // A class can be final XOR sealed XOR non-sealed.
371 if (Modifier.isFinal(modifiers)) {
372 return; // no-op
373 } else {
374 if (isSealed()) {
375 sb.append("sealed ");
376 return;
377 } else {
378 // Check for sealed ancestor, which implies this class
379 // is non-sealed.
380 if (hasSealedAncestor(this)) {
381 sb.append("non-sealed ");
382 }
383 }
384 }
385 }
386
387 private boolean hasSealedAncestor(Class<?> clazz) {
388 // From JLS 8.1.1.2:
389 // "It is a compile-time error if a class has a sealed direct
390 // superclass or a sealed direct superinterface, and is not
391 // declared final, sealed, or non-sealed either explicitly or
392 // implicitly.
393 // Thus, an effect of the sealed keyword is to force all
394 // direct subclasses to explicitly declare whether they are
395 // final, sealed, or non-sealed. This avoids accidentally
396 // exposing a sealed class hierarchy to unwanted subclassing."
397
398 // Therefore, will just check direct superclass and
399 // superinterfaces.
400 var superclass = clazz.getSuperclass();
401 if (superclass != null && superclass.isSealed()) {
402 return true;
403 }
404 for (var superinterface : clazz.getInterfaces()) {
405 if (superinterface.isSealed()) {
406 return true;
407 }
408 }
409 return false;
410 }
411
412 static String typeVarBounds(TypeVariable<?> typeVar) {
413 Type[] bounds = typeVar.getBounds();
414 if (bounds.length == 1 && bounds[0].equals(Object.class)) {
415 return typeVar.getName();
416 } else {
417 return typeVar.getName() + " extends " +
418 Arrays.stream(bounds)
419 .map(Type::getTypeName)
420 .collect(Collectors.joining(" & "));
421 }
422 }
423
424 /**
425 * Returns the {@code Class} object associated with the class or
426 * interface with the given string name. Invoking this method is
427 * equivalent to:
428 *
429 * {@snippet lang="java" :
430 * Class.forName(className, true, currentLoader)
431 * }
432 *
433 * where {@code currentLoader} denotes the defining class loader of
434 * the current class.
435 *
436 * <p> For example, the following code fragment returns the
437 * runtime {@code Class} object for the class named
438 * {@code java.lang.Thread}:
439 *
440 * {@snippet lang="java" :
441 * Class<?> t = Class.forName("java.lang.Thread");
442 * }
443 * <p>
444 * A call to {@code forName("X")} causes the class named
445 * {@code X} to be initialized.
446 *
447 * <p>
448 * In cases where this method is called from a context where there is no
449 * caller frame on the stack (e.g. when called directly from a JNI
450 * attached thread), the system class loader is used.
451 *
452 * @param className the {@linkplain ClassLoader##binary-name binary name}
453 * of the class or the string representing an array type
454 * @return the {@code Class} object for the class with the
455 * specified name.
456 * @throws LinkageError if the linkage fails
457 * @throws ExceptionInInitializerError if the initialization provoked
458 * by this method fails
459 * @throws ClassNotFoundException if the class cannot be located
460 *
461 * @jls 12.2 Loading of Classes and Interfaces
462 * @jls 12.3 Linking of Classes and Interfaces
463 * @jls 12.4 Initialization of Classes and Interfaces
464 */
465 @CallerSensitive
466 public static Class<?> forName(String className)
467 throws ClassNotFoundException {
468 Class<?> caller = Reflection.getCallerClass();
469 return forName(className, caller);
470 }
471
472 // Caller-sensitive adapter method for reflective invocation
473 @CallerSensitiveAdapter
474 private static Class<?> forName(String className, Class<?> caller)
475 throws ClassNotFoundException {
476 ClassLoader loader = (caller == null) ? ClassLoader.getSystemClassLoader()
477 : ClassLoader.getClassLoader(caller);
478 return forName0(className, true, loader, caller);
479 }
480
481 /**
482 * Returns the {@code Class} object associated with the class or
483 * interface with the given string name, using the given class loader.
484 * Given the {@linkplain ClassLoader##binary-name binary name} for a class or interface,
485 * this method attempts to locate and load the class or interface. The specified
486 * class loader is used to load the class or interface. If the parameter
487 * {@code loader} is {@code null}, the class is loaded through the bootstrap
488 * class loader. The class is initialized only if the
489 * {@code initialize} parameter is {@code true} and if it has
490 * not been initialized earlier.
491 *
492 * <p> This method cannot be used to obtain any of the {@code Class} objects
493 * representing primitive types or void, hidden classes or interfaces,
494 * or array classes whose element type is a hidden class or interface.
495 * If {@code name} denotes a primitive type or void, for example {@code I},
496 * an attempt will be made to locate a user-defined class in the unnamed package
497 * whose name is {@code I} instead.
498 * To obtain a {@code Class} object for a named primitive type
499 * such as {@code int} or {@code long} use {@link
500 * #forPrimitiveName(String)}.
501 *
502 * <p> To obtain the {@code Class} object associated with an array class,
503 * the name consists of one or more {@code '['} representing the depth
504 * of the array nesting, followed by the element type as encoded in
505 * {@linkplain ##nameFormat the table} specified in {@code Class.getName()}.
506 *
507 * <p> Examples:
508 * {@snippet lang="java" :
509 * Class<?> threadClass = Class.forName("java.lang.Thread", false, currentLoader);
510 * Class<?> stringArrayClass = Class.forName("[Ljava.lang.String;", false, currentLoader);
511 * Class<?> intArrayClass = Class.forName("[[[I", false, currentLoader); // Class of int[][][]
512 * Class<?> nestedClass = Class.forName("java.lang.Character$UnicodeBlock", false, currentLoader);
513 * Class<?> fooClass = Class.forName("Foo", true, currentLoader);
514 * }
515 *
516 * <p> A call to {@code getName()} on the {@code Class} object returned
517 * from {@code forName(}<i>N</i>{@code )} returns <i>N</i>.
518 *
519 * <p> A call to {@code forName("[L}<i>N</i>{@code ;")} causes the element type
520 * named <i>N</i> to be loaded but not initialized regardless of the value
521 * of the {@code initialize} parameter.
522 *
523 * @apiNote
524 * This method throws errors related to loading, linking or initializing
525 * as specified in Sections {@jls 12.2}, {@jls 12.3}, and {@jls 12.4} of
526 * <cite>The Java Language Specification</cite>.
527 * In addition, this method does not check whether the requested class
528 * is accessible to its caller.
529 *
530 * @param name the {@linkplain ClassLoader##binary-name binary name}
531 * of the class or the string representing an array class
532 *
533 * @param initialize if {@code true} the class will be initialized
534 * (which implies linking). See Section {@jls
535 * 12.4} of <cite>The Java Language
536 * Specification</cite>.
537 * @param loader class loader from which the class must be loaded
538 * @return class object representing the desired class
539 *
540 * @throws LinkageError if the linkage fails
541 * @throws ExceptionInInitializerError if the initialization provoked
542 * by this method fails
543 * @throws ClassNotFoundException if the class cannot be located by
544 * the specified class loader
545 *
546 * @see java.lang.Class#forName(String)
547 * @see java.lang.ClassLoader
548 *
549 * @jls 12.2 Loading of Classes and Interfaces
550 * @jls 12.3 Linking of Classes and Interfaces
551 * @jls 12.4 Initialization of Classes and Interfaces
552 * @jls 13.1 The Form of a Binary
553 * @since 1.2
554 */
555 public static Class<?> forName(String name, boolean initialize, ClassLoader loader)
556 throws ClassNotFoundException
557 {
558 return forName0(name, initialize, loader, null);
559 }
560
561 /** Called after security check for system loader access checks have been made. */
562 private static native Class<?> forName0(String name, boolean initialize,
563 ClassLoader loader,
564 Class<?> caller)
565 throws ClassNotFoundException;
566
567
568 /**
569 * Returns the {@code Class} with the given {@linkplain ClassLoader##binary-name
570 * binary name} in the given module.
571 *
572 * <p> This method attempts to locate and load the class or interface.
573 * It does not link the class, and does not run the class initializer.
574 * If the class is not found, this method returns {@code null}. </p>
575 *
576 * <p> If the class loader of the given module defines other modules and
577 * the given name is a class defined in a different module, this method
578 * returns {@code null} after the class is loaded. </p>
579 *
580 * <p> This method does not check whether the requested class is
581 * accessible to its caller. </p>
582 *
583 * @apiNote
584 * This method does not support loading of array types, unlike
585 * {@link #forName(String, boolean, ClassLoader)}. The class name must be
586 * a binary name. This method returns {@code null} on failure rather than
587 * throwing a {@link ClassNotFoundException}, as is done by
588 * the {@link #forName(String, boolean, ClassLoader)} method.
589 *
590 * @param module A module
591 * @param name The {@linkplain ClassLoader##binary-name binary name}
592 * of the class
593 * @return {@code Class} object of the given name defined in the given module;
594 * {@code null} if not found.
595 *
596 * @throws NullPointerException if the given module or name is {@code null}
597 *
598 * @throws LinkageError if the linkage fails
599 *
600 * @jls 12.2 Loading of Classes and Interfaces
601 * @jls 12.3 Linking of Classes and Interfaces
602 * @since 9
603 */
604 public static Class<?> forName(Module module, String name) {
605 Objects.requireNonNull(module);
606 Objects.requireNonNull(name);
607
608 ClassLoader cl = module.getClassLoader();
609 if (cl != null) {
610 return cl.loadClass(module, name);
611 } else {
612 return BootLoader.loadClass(module, name);
613 }
614 }
615
616 /**
617 * {@return {@code true} if this {@code Class} object represents an identity class,
618 * otherwise {@code false}}
619 *
620 * <ul>
621 * <li>
622 * If this {@code Class} object represents an array type this method returns {@code true}.
623 * <li>
624 * If this {@code Class} object represents an interface, a primitive type,
625 * or {@code void} this method returns {@code false}.
626 * <li>
627 * For all other {@code Class} objects, this method returns {@code true} if either
628 * preview features are disabled or {@linkplain Modifier#IDENTITY} is set in the
629 * {@linkplain #getModifiers() class modifiers}.
630 * </ul>
631 * @see AccessFlag#IDENTITY
632 * @since Valhalla
633 */
634 @PreviewFeature(feature = PreviewFeature.Feature.VALUE_OBJECTS, reflective=true)
635 public boolean isIdentity() {
636 if (isPrimitive()) {
637 return false;
638 } else if (PreviewFeatures.isEnabled()) {
639 return isArray() || Modifier.isIdentity(modifiers);
640 } else {
641 return !isInterface();
642 }
643 }
644
645 /**
646 * {@return {@code true} if this {@code Class} object represents a value class,
647 * otherwise {@code false}}
648 * <ul>
649 * <li>
650 * If this {@code Class} object represents an array type this method returns {@code false}.
651 * <li>
652 * If this {@code Class} object represents an interface, a primitive type,
653 * or {@code void} this method returns {@code true} only if preview features are enabled.
654 * <li>
655 * For all other {@code Class} objects, this method returns {@code true} only if
656 * preview features are enabled and {@linkplain Modifier#IDENTITY} is not set in the
657 * {@linkplain #getModifiers() class modifiers}.
658 * </ul>
659 * @see AccessFlag#IDENTITY
660 * @since Valhalla
661 */
662 @PreviewFeature(feature = PreviewFeature.Feature.VALUE_OBJECTS, reflective=true)
663 public boolean isValue() {
664 if (!PreviewFeatures.isEnabled()) {
665 return false;
666 }
667 return !isIdentity();
668 }
669
670 /**
671 * {@return the {@code Class} object associated with the
672 * {@linkplain #isPrimitive() primitive type} of the given name}
673 * If the argument is not the name of a primitive type, {@code
674 * null} is returned.
675 *
676 * @param primitiveName the name of the primitive type to find
677 *
678 * @throws NullPointerException if the argument is {@code null}
679 *
680 * @jls 4.2 Primitive Types and Values
681 * @jls 15.8.2 Class Literals
682 * @since 22
683 */
684 public static Class<?> forPrimitiveName(String primitiveName) {
685 return switch(primitiveName) {
686 // Integral types
687 case "int" -> int.class;
688 case "long" -> long.class;
689 case "short" -> short.class;
690 case "char" -> char.class;
691 case "byte" -> byte.class;
692
693 // Floating-point types
694 case "float" -> float.class;
695 case "double" -> double.class;
696
697 // Other types
698 case "boolean" -> boolean.class;
699 case "void" -> void.class;
700
701 default -> null;
702 };
703 }
704
705 /**
706 * Creates a new instance of the class represented by this {@code Class}
707 * object. The class is instantiated as if by a {@code new}
708 * expression with an empty argument list. The class is initialized if it
709 * has not already been initialized.
710 *
711 * @deprecated This method propagates any exception thrown by the
712 * nullary constructor, including a checked exception. Use of
713 * this method effectively bypasses the compile-time exception
714 * checking that would otherwise be performed by the compiler.
715 * The {@link
716 * java.lang.reflect.Constructor#newInstance(java.lang.Object...)
717 * Constructor.newInstance} method avoids this problem by wrapping
718 * any exception thrown by the constructor in a (checked) {@link
719 * java.lang.reflect.InvocationTargetException}.
720 *
721 * <p>The call
722 *
723 * {@snippet lang="java" :
724 * clazz.newInstance()
725 * }
726 *
727 * can be replaced by
728 *
729 * {@snippet lang="java" :
730 * clazz.getDeclaredConstructor().newInstance()
731 * }
732 *
733 * The latter sequence of calls is inferred to be able to throw
734 * the additional exception types {@link
735 * InvocationTargetException} and {@link
736 * NoSuchMethodException}. Both of these exception types are
737 * subclasses of {@link ReflectiveOperationException}.
738 *
739 * @return a newly allocated instance of the class represented by this
740 * object.
741 * @throws IllegalAccessException if the class or its nullary
742 * constructor is not accessible.
743 * @throws InstantiationException
744 * if this {@code Class} represents an abstract class,
745 * an interface, an array class, a primitive type, or void;
746 * or if the class has no nullary constructor;
747 * or if the instantiation fails for some other reason.
748 * @throws ExceptionInInitializerError if the initialization
749 * provoked by this method fails.
750 */
751 @CallerSensitive
752 @Deprecated(since="9")
753 public T newInstance()
754 throws InstantiationException, IllegalAccessException
755 {
756 // Constructor lookup
757 Constructor<T> tmpConstructor = cachedConstructor;
758 if (tmpConstructor == null) {
759 if (this == Class.class) {
760 throw new IllegalAccessException(
761 "Can not call newInstance() on the Class for java.lang.Class"
762 );
763 }
764 try {
765 Class<?>[] empty = {};
766 final Constructor<T> c = getReflectionFactory().copyConstructor(
767 getConstructor0(empty, Member.DECLARED));
768 // Disable accessibility checks on the constructor
769 // access check is done with the true caller
770 c.setAccessible(true);
771 cachedConstructor = tmpConstructor = c;
772 } catch (NoSuchMethodException e) {
773 throw (InstantiationException)
774 new InstantiationException(getName()).initCause(e);
775 }
776 }
777
778 try {
779 Class<?> caller = Reflection.getCallerClass();
780 return getReflectionFactory().newInstance(tmpConstructor, null, caller);
781 } catch (InvocationTargetException e) {
782 Unsafe.getUnsafe().throwException(e.getTargetException());
783 // Not reached
784 return null;
785 }
786 }
787
788 private transient volatile Constructor<T> cachedConstructor;
789
790 /**
791 * Determines if the specified {@code Object} is assignment-compatible
792 * with the object represented by this {@code Class}. This method is
793 * the dynamic equivalent of the Java language {@code instanceof}
794 * operator. The method returns {@code true} if the specified
795 * {@code Object} argument is non-null and can be cast to the
796 * reference type represented by this {@code Class} object without
797 * raising a {@code ClassCastException.} It returns {@code false}
798 * otherwise.
799 *
800 * <p> Specifically, if this {@code Class} object represents a
801 * declared class, this method returns {@code true} if the specified
802 * {@code Object} argument is an instance of the represented class (or
803 * of any of its subclasses); it returns {@code false} otherwise. If
804 * this {@code Class} object represents an array class, this method
805 * returns {@code true} if the specified {@code Object} argument
806 * can be converted to an object of the array class by an identity
807 * conversion or by a widening reference conversion; it returns
808 * {@code false} otherwise. If this {@code Class} object
809 * represents an interface, this method returns {@code true} if the
810 * class or any superclass of the specified {@code Object} argument
811 * implements this interface; it returns {@code false} otherwise. If
812 * this {@code Class} object represents a primitive type, this method
813 * returns {@code false}.
814 *
815 * @param obj the object to check
816 * @return true if {@code obj} is an instance of this class
817 *
818 * @since 1.1
819 */
820 @IntrinsicCandidate
821 public native boolean isInstance(Object obj);
822
823
824 /**
825 * Determines if the class or interface represented by this
826 * {@code Class} object is either the same as, or is a superclass or
827 * superinterface of, the class or interface represented by the specified
828 * {@code Class} parameter. It returns {@code true} if so;
829 * otherwise it returns {@code false}. If this {@code Class}
830 * object represents a primitive type, this method returns
831 * {@code true} if the specified {@code Class} parameter is
832 * exactly this {@code Class} object; otherwise it returns
833 * {@code false}.
834 *
835 * <p> Specifically, this method tests whether the type represented by the
836 * specified {@code Class} parameter can be converted to the type
837 * represented by this {@code Class} object via an identity conversion
838 * or via a widening reference conversion. See <cite>The Java Language
839 * Specification</cite>, sections {@jls 5.1.1} and {@jls 5.1.4},
840 * for details.
841 *
842 * @param cls the {@code Class} object to be checked
843 * @return the {@code boolean} value indicating whether objects of the
844 * type {@code cls} can be assigned to objects of this class
845 * @throws NullPointerException if the specified Class parameter is
846 * null.
847 * @since 1.1
848 */
849 @IntrinsicCandidate
850 public native boolean isAssignableFrom(Class<?> cls);
851
852
853 /**
854 * Determines if this {@code Class} object represents an
855 * interface type.
856 *
857 * @return {@code true} if this {@code Class} object represents an interface;
858 * {@code false} otherwise.
859 */
860 public boolean isInterface() {
861 return Modifier.isInterface(modifiers);
862 }
863
864
865 /**
866 * Determines if this {@code Class} object represents an array class.
867 *
868 * @return {@code true} if this {@code Class} object represents an array class;
869 * {@code false} otherwise.
870 * @since 1.1
871 */
872 public boolean isArray() {
873 return componentType != null;
874 }
875
876
877 /**
878 * Determines if this {@code Class} object represents a primitive
879 * type or void.
880 *
881 * <p> There are nine predefined {@code Class} objects to
882 * represent the eight primitive types and void. These are
883 * created by the Java Virtual Machine, and have the same
884 * {@linkplain #getName() names} as the primitive types that they
885 * represent, namely {@code boolean}, {@code byte}, {@code char},
886 * {@code short}, {@code int}, {@code long}, {@code float}, and
887 * {@code double}.
888 *
889 * <p>No other class objects are considered primitive.
890 *
891 * @apiNote
892 * A {@code Class} object represented by a primitive type can be
893 * accessed via the {@code TYPE} public static final variables
894 * defined in the primitive wrapper classes such as {@link
895 * java.lang.Integer#TYPE Integer.TYPE}. In the Java programming
896 * language, the objects may be referred to by a class literal
897 * expression such as {@code int.class}. The {@code Class} object
898 * for void can be expressed as {@code void.class} or {@link
899 * java.lang.Void#TYPE Void.TYPE}.
900 *
901 * @return true if and only if this class represents a primitive type
902 *
903 * @see java.lang.Boolean#TYPE
904 * @see java.lang.Character#TYPE
905 * @see java.lang.Byte#TYPE
906 * @see java.lang.Short#TYPE
907 * @see java.lang.Integer#TYPE
908 * @see java.lang.Long#TYPE
909 * @see java.lang.Float#TYPE
910 * @see java.lang.Double#TYPE
911 * @see java.lang.Void#TYPE
912 * @since 1.1
913 * @jls 15.8.2 Class Literals
914 */
915 public boolean isPrimitive() {
916 return primitive;
917 }
918
919 /**
920 * Returns true if this {@code Class} object represents an annotation
921 * interface. Note that if this method returns true, {@link #isInterface()}
922 * would also return true, as all annotation interfaces are also interfaces.
923 *
924 * @return {@code true} if this {@code Class} object represents an annotation
925 * interface; {@code false} otherwise
926 * @since 1.5
927 */
928 public boolean isAnnotation() {
929 return (getModifiers() & ANNOTATION) != 0;
930 }
931
932 /**
933 *{@return {@code true} if and only if this class has the synthetic modifier
934 * bit set}
935 *
936 * @jls 13.1 The Form of a Binary
937 * @jvms 4.1 The {@code ClassFile} Structure
938 * @see <a
939 * href="{@docRoot}/java.base/java/lang/reflect/package-summary.html#LanguageJvmModel">Java
940 * programming language and JVM modeling in core reflection</a>
941 * @since 1.5
942 */
943 public boolean isSynthetic() {
944 return (getModifiers() & SYNTHETIC) != 0;
945 }
946
947 /**
948 * Returns the name of the entity (class, interface, array class,
949 * primitive type, or void) represented by this {@code Class} object.
950 *
951 * <p> If this {@code Class} object represents a class or interface,
952 * not an array class, then:
953 * <ul>
954 * <li> If the class or interface is not {@linkplain #isHidden() hidden},
955 * then the {@linkplain ClassLoader##binary-name binary name}
956 * of the class or interface is returned.
957 * <li> If the class or interface is hidden, then the result is a string
958 * of the form: {@code N + '/' + <suffix>}
959 * where {@code N} is the {@linkplain ClassLoader##binary-name binary name}
960 * indicated by the {@code class} file passed to
961 * {@link java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
962 * Lookup::defineHiddenClass}, and {@code <suffix>} is an unqualified name.
963 * </ul>
964 *
965 * <p> If this {@code Class} object represents an array class, then
966 * the result is a string consisting of one or more '{@code [}' characters
967 * representing the depth of the array nesting, followed by the element
968 * type as encoded using the following table:
969 *
970 * <blockquote><table class="striped" id="nameFormat">
971 * <caption style="display:none">Element types and encodings</caption>
972 * <thead>
973 * <tr><th scope="col"> Element Type <th scope="col"> Encoding
974 * </thead>
975 * <tbody style="text-align:left">
976 * <tr><th scope="row"> {@code boolean} <td style="text-align:center"> {@code Z}
977 * <tr><th scope="row"> {@code byte} <td style="text-align:center"> {@code B}
978 * <tr><th scope="row"> {@code char} <td style="text-align:center"> {@code C}
979 * <tr><th scope="row"> class or interface with {@linkplain ClassLoader##binary-name binary name} <i>N</i>
980 * <td style="text-align:center"> {@code L}<em>N</em>{@code ;}
981 * <tr><th scope="row"> {@code double} <td style="text-align:center"> {@code D}
982 * <tr><th scope="row"> {@code float} <td style="text-align:center"> {@code F}
983 * <tr><th scope="row"> {@code int} <td style="text-align:center"> {@code I}
984 * <tr><th scope="row"> {@code long} <td style="text-align:center"> {@code J}
985 * <tr><th scope="row"> {@code short} <td style="text-align:center"> {@code S}
986 * </tbody>
987 * </table></blockquote>
988 *
989 * <p> If this {@code Class} object represents a primitive type or {@code void},
990 * then the result is a string with the same spelling as the Java language
991 * keyword which corresponds to the primitive type or {@code void}.
992 *
993 * <p> Examples:
994 * <blockquote><pre>
995 * String.class.getName()
996 * returns "java.lang.String"
997 * Character.UnicodeBlock.class.getName()
998 * returns "java.lang.Character$UnicodeBlock"
999 * byte.class.getName()
1000 * returns "byte"
1001 * (new Object[3]).getClass().getName()
1002 * returns "[Ljava.lang.Object;"
1003 * (new int[3][4][5][6][7][8][9]).getClass().getName()
1004 * returns "[[[[[[[I"
1005 * </pre></blockquote>
1006 *
1007 * @apiNote
1008 * Distinct class objects can have the same name but different class loaders.
1009 *
1010 * @return the name of the class, interface, or other entity
1011 * represented by this {@code Class} object.
1012 * @jls 13.1 The Form of a Binary
1013 */
1014 public String getName() {
1015 String name = this.name;
1016 return name != null ? name : initClassName();
1017 }
1018
1019 // Cache the name to reduce the number of calls into the VM.
1020 // This field would be set by VM itself during initClassName call.
1021 private transient String name;
1022 private native String initClassName();
1023
1024 /**
1025 * Returns the class loader for the class. Some implementations may use
1026 * null to represent the bootstrap class loader. This method will return
1027 * null in such implementations if this class was loaded by the bootstrap
1028 * class loader.
1029 *
1030 * <p>If this {@code Class} object
1031 * represents a primitive type or void, null is returned.
1032 *
1033 * @return the class loader that loaded the class or interface
1034 * represented by this {@code Class} object.
1035 * @see java.lang.ClassLoader
1036 */
1037 public ClassLoader getClassLoader() {
1038 return classLoader;
1039 }
1040
1041 // Package-private to allow ClassLoader access
1042 ClassLoader getClassLoader0() { return classLoader; }
1043
1044 /**
1045 * Returns the module that this class or interface is a member of.
1046 *
1047 * If this class represents an array type then this method returns the
1048 * {@code Module} for the element type. If this class represents a
1049 * primitive type or void, then the {@code Module} object for the
1050 * {@code java.base} module is returned.
1051 *
1052 * If this class is in an unnamed module then the {@linkplain
1053 * ClassLoader#getUnnamedModule() unnamed} {@code Module} of the class
1054 * loader for this class is returned.
1055 *
1056 * @return the module that this class or interface is a member of
1057 *
1058 * @since 9
1059 */
1060 public Module getModule() {
1061 return module;
1062 }
1063
1064 // set by VM
1065 @Stable
1066 private transient Module module;
1067
1068 // Initialized in JVM not by private constructor
1069 // This field is filtered from reflection access, i.e. getDeclaredField
1070 // will throw NoSuchFieldException
1071 private final ClassLoader classLoader;
1072
1073 private transient Object classData; // Set by VM
1074 private transient Object[] signers; // Read by VM, mutable
1075 private final transient char modifiers; // Set by the VM
1076 private final transient boolean primitive; // Set by the VM if the Class is a primitive type.
1077
1078 // package-private
1079 Object getClassData() {
1080 return classData;
1081 }
1082
1083 /**
1084 * Returns an array of {@code TypeVariable} objects that represent the
1085 * type variables declared by the generic declaration represented by this
1086 * {@code GenericDeclaration} object, in declaration order. Returns an
1087 * array of length 0 if the underlying generic declaration declares no type
1088 * variables.
1089 *
1090 * @return an array of {@code TypeVariable} objects that represent
1091 * the type variables declared by this generic declaration
1092 * @throws java.lang.reflect.GenericSignatureFormatError if the generic
1093 * signature of this generic declaration does not conform to
1094 * the format specified in section {@jvms 4.7.9} of
1095 * <cite>The Java Virtual Machine Specification</cite>
1096 * @since 1.5
1097 */
1098 @SuppressWarnings("unchecked")
1099 public TypeVariable<Class<T>>[] getTypeParameters() {
1100 ClassRepository info = getGenericInfo();
1101 if (info != null)
1102 return (TypeVariable<Class<T>>[])info.getTypeParameters();
1103 else
1104 return (TypeVariable<Class<T>>[])new TypeVariable<?>[0];
1105 }
1106
1107
1108 /**
1109 * Returns the {@code Class} representing the direct superclass of the
1110 * entity (class, interface, primitive type or void) represented by
1111 * this {@code Class}. If this {@code Class} represents either the
1112 * {@code Object} class, an interface, a primitive type, or void, then
1113 * null is returned. If this {@code Class} object represents an array class
1114 * then the {@code Class} object representing the {@code Object} class is
1115 * returned.
1116 *
1117 * @return the direct superclass of the class represented by this {@code Class} object
1118 */
1119 @IntrinsicCandidate
1120 public native Class<? super T> getSuperclass();
1121
1122
1123 /**
1124 * Returns the {@code Type} representing the direct superclass of
1125 * the entity (class, interface, primitive type or void) represented by
1126 * this {@code Class} object.
1127 *
1128 * <p>If the superclass is a parameterized type, the {@code Type}
1129 * object returned must accurately reflect the actual type
1130 * arguments used in the source code. The parameterized type
1131 * representing the superclass is created if it had not been
1132 * created before. See the declaration of {@link
1133 * java.lang.reflect.ParameterizedType ParameterizedType} for the
1134 * semantics of the creation process for parameterized types. If
1135 * this {@code Class} object represents either the {@code Object}
1136 * class, an interface, a primitive type, or void, then null is
1137 * returned. If this {@code Class} object represents an array class
1138 * then the {@code Class} object representing the {@code Object} class is
1139 * returned.
1140 *
1141 * @throws java.lang.reflect.GenericSignatureFormatError if the generic
1142 * class signature does not conform to the format specified in
1143 * section {@jvms 4.7.9} of <cite>The Java Virtual
1144 * Machine Specification</cite>
1145 * @throws TypeNotPresentException if the generic superclass
1146 * refers to a non-existent type declaration
1147 * @throws java.lang.reflect.MalformedParameterizedTypeException if the
1148 * generic superclass refers to a parameterized type that cannot be
1149 * instantiated for any reason
1150 * @return the direct superclass of the class represented by this {@code Class} object
1151 * @since 1.5
1152 */
1153 public Type getGenericSuperclass() {
1154 ClassRepository info = getGenericInfo();
1155 if (info == null) {
1156 return getSuperclass();
1157 }
1158
1159 // Historical irregularity:
1160 // Generic signature marks interfaces with superclass = Object
1161 // but this API returns null for interfaces
1162 if (isInterface()) {
1163 return null;
1164 }
1165
1166 return info.getSuperclass();
1167 }
1168
1169 /**
1170 * Gets the package of this class.
1171 *
1172 * <p>If this class represents an array type, a primitive type or void,
1173 * this method returns {@code null}.
1174 *
1175 * @return the package of this class.
1176 */
1177 public Package getPackage() {
1178 if (isPrimitive() || isArray()) {
1179 return null;
1180 }
1181 ClassLoader cl = classLoader;
1182 return cl != null ? cl.definePackage(this)
1183 : BootLoader.definePackage(this);
1184 }
1185
1186 /**
1187 * Returns the fully qualified package name.
1188 *
1189 * <p> If this class is a top level class, then this method returns the fully
1190 * qualified name of the package that the class is a member of, or the
1191 * empty string if the class is in an unnamed package.
1192 *
1193 * <p> If this class is a member class, then this method is equivalent to
1194 * invoking {@code getPackageName()} on the {@linkplain #getEnclosingClass
1195 * enclosing class}.
1196 *
1197 * <p> If this class is a {@linkplain #isLocalClass local class} or an {@linkplain
1198 * #isAnonymousClass() anonymous class}, then this method is equivalent to
1199 * invoking {@code getPackageName()} on the {@linkplain #getDeclaringClass
1200 * declaring class} of the {@linkplain #getEnclosingMethod enclosing method} or
1201 * {@linkplain #getEnclosingConstructor enclosing constructor}.
1202 *
1203 * <p> If this class represents an array type then this method returns the
1204 * package name of the element type. If this class represents a primitive
1205 * type or void then the package name "{@code java.lang}" is returned.
1206 *
1207 * @return the fully qualified package name
1208 *
1209 * @since 9
1210 * @jls 6.7 Fully Qualified Names and Canonical Names
1211 */
1212 public String getPackageName() {
1213 String pn = this.packageName;
1214 if (pn == null) {
1215 Class<?> c = isArray() ? elementType() : this;
1216 if (c.isPrimitive()) {
1217 pn = "java.lang";
1218 } else {
1219 String cn = c.getName();
1220 int dot = cn.lastIndexOf('.');
1221 pn = (dot != -1) ? cn.substring(0, dot).intern() : "";
1222 }
1223 this.packageName = pn;
1224 }
1225 return pn;
1226 }
1227
1228 // cached package name
1229 private transient String packageName;
1230
1231 /**
1232 * Returns the interfaces directly implemented by the class or interface
1233 * represented by this {@code Class} object.
1234 *
1235 * <p>If this {@code Class} object represents a class, the return value is an array
1236 * containing objects representing all interfaces directly implemented by
1237 * the class. The order of the interface objects in the array corresponds
1238 * to the order of the interface names in the {@code implements} clause of
1239 * the declaration of the class represented by this {@code Class} object. For example,
1240 * given the declaration:
1241 * <blockquote>
1242 * {@code class Shimmer implements FloorWax, DessertTopping { ... }}
1243 * </blockquote>
1244 * suppose the value of {@code s} is an instance of
1245 * {@code Shimmer}; the value of the expression:
1246 * <blockquote>
1247 * {@code s.getClass().getInterfaces()[0]}
1248 * </blockquote>
1249 * is the {@code Class} object that represents interface
1250 * {@code FloorWax}; and the value of:
1251 * <blockquote>
1252 * {@code s.getClass().getInterfaces()[1]}
1253 * </blockquote>
1254 * is the {@code Class} object that represents interface
1255 * {@code DessertTopping}.
1256 *
1257 * <p>If this {@code Class} object represents an interface, the array contains objects
1258 * representing all interfaces directly extended by the interface. The
1259 * order of the interface objects in the array corresponds to the order of
1260 * the interface names in the {@code extends} clause of the declaration of
1261 * the interface represented by this {@code Class} object.
1262 *
1263 * <p>If this {@code Class} object represents a class or interface that implements no
1264 * interfaces, the method returns an array of length 0.
1265 *
1266 * <p>If this {@code Class} object represents a primitive type or void, the method
1267 * returns an array of length 0.
1268 *
1269 * <p>If this {@code Class} object represents an array type, the
1270 * interfaces {@code Cloneable} and {@code java.io.Serializable} are
1271 * returned in that order.
1272 *
1273 * @return an array of interfaces directly implemented by this class
1274 */
1275 public Class<?>[] getInterfaces() {
1276 // defensively copy before handing over to user code
1277 return getInterfaces(true);
1278 }
1279
1280 private Class<?>[] getInterfaces(boolean cloneArray) {
1281 ReflectionData<T> rd = reflectionData();
1282 Class<?>[] interfaces = rd.interfaces;
1283 if (interfaces == null) {
1284 interfaces = getInterfaces0();
1285 rd.interfaces = interfaces;
1286 }
1287 // defensively copy if requested
1288 return cloneArray ? interfaces.clone() : interfaces;
1289 }
1290
1291 private native Class<?>[] getInterfaces0();
1292
1293 /**
1294 * Returns the {@code Type}s representing the interfaces
1295 * directly implemented by the class or interface represented by
1296 * this {@code Class} object.
1297 *
1298 * <p>If a superinterface is a parameterized type, the
1299 * {@code Type} object returned for it must accurately reflect
1300 * the actual type arguments used in the source code. The
1301 * parameterized type representing each superinterface is created
1302 * if it had not been created before. See the declaration of
1303 * {@link java.lang.reflect.ParameterizedType ParameterizedType}
1304 * for the semantics of the creation process for parameterized
1305 * types.
1306 *
1307 * <p>If this {@code Class} object represents a class, the return value is an array
1308 * containing objects representing all interfaces directly implemented by
1309 * the class. The order of the interface objects in the array corresponds
1310 * to the order of the interface names in the {@code implements} clause of
1311 * the declaration of the class represented by this {@code Class} object.
1312 *
1313 * <p>If this {@code Class} object represents an interface, the array contains objects
1314 * representing all interfaces directly extended by the interface. The
1315 * order of the interface objects in the array corresponds to the order of
1316 * the interface names in the {@code extends} clause of the declaration of
1317 * the interface represented by this {@code Class} object.
1318 *
1319 * <p>If this {@code Class} object represents a class or interface that implements no
1320 * interfaces, the method returns an array of length 0.
1321 *
1322 * <p>If this {@code Class} object represents a primitive type or void, the method
1323 * returns an array of length 0.
1324 *
1325 * <p>If this {@code Class} object represents an array type, the
1326 * interfaces {@code Cloneable} and {@code java.io.Serializable} are
1327 * returned in that order.
1328 *
1329 * @throws java.lang.reflect.GenericSignatureFormatError
1330 * if the generic class signature does not conform to the
1331 * format specified in section {@jvms 4.7.9} of <cite>The
1332 * Java Virtual Machine Specification</cite>
1333 * @throws TypeNotPresentException if any of the generic
1334 * superinterfaces refers to a non-existent type declaration
1335 * @throws java.lang.reflect.MalformedParameterizedTypeException
1336 * if any of the generic superinterfaces refer to a parameterized
1337 * type that cannot be instantiated for any reason
1338 * @return an array of interfaces directly implemented by this class
1339 * @since 1.5
1340 */
1341 public Type[] getGenericInterfaces() {
1342 ClassRepository info = getGenericInfo();
1343 return (info == null) ? getInterfaces() : info.getSuperInterfaces();
1344 }
1345
1346
1347 /**
1348 * Returns the {@code Class} representing the component type of an
1349 * array. If this class does not represent an array class this method
1350 * returns null.
1351 *
1352 * @return the {@code Class} representing the component type of this
1353 * class if this class is an array
1354 * @see java.lang.reflect.Array
1355 * @since 1.1
1356 */
1357 public Class<?> getComponentType() {
1358 return componentType;
1359 }
1360
1361 // The componentType field's null value is the sole indication that the class
1362 // is an array - see isArray().
1363 private transient final Class<?> componentType;
1364
1365 /*
1366 * Returns the {@code Class} representing the element type of an array class.
1367 * If this class does not represent an array class, then this method returns
1368 * {@code null}.
1369 */
1370 private Class<?> elementType() {
1371 if (!isArray()) return null;
1372
1373 Class<?> c = this;
1374 while (c.isArray()) {
1375 c = c.getComponentType();
1376 }
1377 return c;
1378 }
1379
1380 /**
1381 * Returns the Java language modifiers for this class or interface, encoded
1382 * in an integer. The modifiers consist of the Java Virtual Machine's
1383 * constants for {@code public}, {@code protected},
1384 * {@code private}, {@code final}, {@code static},
1385 * {@code abstract} and {@code interface}; they should be decoded
1386 * using the methods of class {@code Modifier}.
1387 *
1388 * <p> If the underlying class is an array class:
1389 * <ul>
1390 * <li> its {@code public}, {@code private} and {@code protected}
1391 * modifiers are the same as those of its component type
1392 * <li> its {@code abstract} and {@code final} modifiers are always
1393 * {@code true}
1394 * <li> its interface modifier is always {@code false}, even when
1395 * the component type is an interface
1396 * <li> its {@code identity} modifier is always true
1397 * </ul>
1398 * If this {@code Class} object represents a primitive type or
1399 * void, its {@code public}, {@code abstract}, and {@code final}
1400 * modifiers are always {@code true}.
1401 * For {@code Class} objects representing void, primitive types, and
1402 * arrays, the values of other modifiers are {@code false} other
1403 * than as specified above.
1404 *
1405 * <p> The modifier encodings are defined in section {@jvms 4.1}
1406 * of <cite>The Java Virtual Machine Specification</cite>.
1407 *
1408 * @return the {@code int} representing the modifiers for this class
1409 * @see java.lang.reflect.Modifier
1410 * @see #accessFlags()
1411 * @see <a
1412 * href="{@docRoot}/java.base/java/lang/reflect/package-summary.html#LanguageJvmModel">Java
1413 * programming language and JVM modeling in core reflection</a>
1414 * @since 1.1
1415 * @jls 8.1.1 Class Modifiers
1416 * @jls 9.1.1 Interface Modifiers
1417 * @jvms 4.1 The {@code ClassFile} Structure
1418 */
1419 public int getModifiers() { return modifiers; }
1420
1421 /**
1422 * {@return an unmodifiable set of the {@linkplain AccessFlag access
1423 * flags} for this class, possibly empty}
1424 * The {@code AccessFlags} may depend on the class file format version of the class.
1425 *
1426 * <p> If the underlying class is an array class:
1427 * <ul>
1428 * <li> its {@code PUBLIC}, {@code PRIVATE} and {@code PROTECTED}
1429 * access flags are the same as those of its component type
1430 * <li> its {@code ABSTRACT} and {@code FINAL} flags are present
1431 * <li> its {@code INTERFACE} flag is absent, even when the
1432 * component type is an interface
1433 * <li> its {@code identity} modifier is always true
1434 * </ul>
1435 * If this {@code Class} object represents a primitive type or
1436 * void, the flags are {@code PUBLIC}, {@code ABSTRACT}, and
1437 * {@code FINAL}.
1438 * For {@code Class} objects representing void, primitive types, and
1439 * arrays, access flags are absent other than as specified above.
1440 *
1441 * @see #getModifiers()
1442 * @jvms 4.1 The ClassFile Structure
1443 * @jvms 4.7.6 The InnerClasses Attribute
1444 * @since 20
1445 */
1446 public Set<AccessFlag> accessFlags() {
1447 // Location.CLASS allows SUPER and AccessFlag.MODULE which
1448 // INNER_CLASS forbids. INNER_CLASS allows PRIVATE, PROTECTED,
1449 // and STATIC, which are not allowed on Location.CLASS.
1450 // Use getClassAccessFlagsRaw to expose SUPER status.
1451 // Arrays need to use PRIVATE/PROTECTED from its component modifiers.
1452 var location = (isMemberClass() || isLocalClass() ||
1453 isAnonymousClass() || isArray()) ?
1454 AccessFlag.Location.INNER_CLASS :
1455 AccessFlag.Location.CLASS;
1456 int accessFlags = location == AccessFlag.Location.CLASS ? getClassAccessFlagsRaw() : getModifiers();
1457 var reflectionFactory = getReflectionFactory();
1458 var ans = reflectionFactory.parseAccessFlags(accessFlags, location, this);
1459 if (PreviewFeatures.isEnabled() && reflectionFactory.classFileFormatVersion(this) != ClassFileFormatVersion.CURRENT_PREVIEW_FEATURES
1460 && isIdentity()) {
1461 var set = new HashSet<>(ans);
1462 set.add(AccessFlag.IDENTITY);
1463 return Set.copyOf(set);
1464 }
1465 return ans;
1466 }
1467
1468 /**
1469 * Gets the signers of this class.
1470 *
1471 * @return the signers of this class, or null if there are no signers. In
1472 * particular, this method returns null if this {@code Class} object represents
1473 * a primitive type or void.
1474 * @since 1.1
1475 */
1476
1477 public Object[] getSigners() {
1478 var signers = this.signers;
1479 return signers == null ? null : signers.clone();
1480 }
1481
1482 /**
1483 * Set the signers of this class.
1484 */
1485 void setSigners(Object[] signers) {
1486 if (!isPrimitive() && !isArray()) {
1487 this.signers = signers;
1488 }
1489 }
1490
1491 /**
1492 * If this {@code Class} object represents a local or anonymous
1493 * class within a method, returns a {@link
1494 * java.lang.reflect.Method Method} object representing the
1495 * immediately enclosing method of the underlying class. Returns
1496 * {@code null} otherwise.
1497 *
1498 * In particular, this method returns {@code null} if the underlying
1499 * class is a local or anonymous class immediately enclosed by a class or
1500 * interface declaration, instance initializer or static initializer.
1501 *
1502 * @return the immediately enclosing method of the underlying class, if
1503 * that class is a local or anonymous class; otherwise {@code null}.
1504 *
1505 * @since 1.5
1506 */
1507 public Method getEnclosingMethod() {
1508 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1509
1510 if (enclosingInfo == null)
1511 return null;
1512 else {
1513 if (!enclosingInfo.isMethod())
1514 return null;
1515
1516 MethodRepository typeInfo = MethodRepository.make(enclosingInfo.getDescriptor(),
1517 getFactory());
1518 Class<?> returnType = toClass(typeInfo.getReturnType());
1519 Type [] parameterTypes = typeInfo.getParameterTypes();
1520 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length];
1521
1522 // Convert Types to Classes; returned types *should*
1523 // be class objects since the methodDescriptor's used
1524 // don't have generics information
1525 for(int i = 0; i < parameterClasses.length; i++)
1526 parameterClasses[i] = toClass(parameterTypes[i]);
1527
1528 final Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass();
1529 Method[] candidates = enclosingCandidate.privateGetDeclaredMethods(false);
1530
1531 /*
1532 * Loop over all declared methods; match method name,
1533 * number of and type of parameters, *and* return
1534 * type. Matching return type is also necessary
1535 * because of covariant returns, etc.
1536 */
1537 ReflectionFactory fact = getReflectionFactory();
1538 for (Method m : candidates) {
1539 if (m.getName().equals(enclosingInfo.getName()) &&
1540 arrayContentsEq(parameterClasses,
1541 fact.getExecutableSharedParameterTypes(m))) {
1542 // finally, check return type
1543 if (m.getReturnType().equals(returnType)) {
1544 return fact.copyMethod(m);
1545 }
1546 }
1547 }
1548
1549 throw new InternalError("Enclosing method not found");
1550 }
1551 }
1552
1553 private native Object[] getEnclosingMethod0();
1554
1555 private EnclosingMethodInfo getEnclosingMethodInfo() {
1556 Object[] enclosingInfo = getEnclosingMethod0();
1557 if (enclosingInfo == null)
1558 return null;
1559 else {
1560 return new EnclosingMethodInfo(enclosingInfo);
1561 }
1562 }
1563
1564 private static final class EnclosingMethodInfo {
1565 private final Class<?> enclosingClass;
1566 private final String name;
1567 private final String descriptor;
1568
1569 static void validate(Object[] enclosingInfo) {
1570 if (enclosingInfo.length != 3)
1571 throw new InternalError("Malformed enclosing method information");
1572 try {
1573 // The array is expected to have three elements:
1574
1575 // the immediately enclosing class
1576 Class<?> enclosingClass = (Class<?>)enclosingInfo[0];
1577 assert(enclosingClass != null);
1578
1579 // the immediately enclosing method or constructor's
1580 // name (can be null).
1581 String name = (String)enclosingInfo[1];
1582
1583 // the immediately enclosing method or constructor's
1584 // descriptor (null iff name is).
1585 String descriptor = (String)enclosingInfo[2];
1586 assert((name != null && descriptor != null) || name == descriptor);
1587 } catch (ClassCastException cce) {
1588 throw new InternalError("Invalid type in enclosing method information", cce);
1589 }
1590 }
1591
1592 EnclosingMethodInfo(Object[] enclosingInfo) {
1593 validate(enclosingInfo);
1594 this.enclosingClass = (Class<?>)enclosingInfo[0];
1595 this.name = (String)enclosingInfo[1];
1596 this.descriptor = (String)enclosingInfo[2];
1597 }
1598
1599 boolean isPartial() {
1600 return enclosingClass == null || name == null || descriptor == null;
1601 }
1602
1603 boolean isConstructor() { return !isPartial() && ConstantDescs.INIT_NAME.equals(name); }
1604
1605 boolean isMethod() { return !isPartial() && !isConstructor() && !ConstantDescs.CLASS_INIT_NAME.equals(name); }
1606
1607 Class<?> getEnclosingClass() { return enclosingClass; }
1608
1609 String getName() { return name; }
1610
1611 String getDescriptor() { return descriptor; }
1612
1613 }
1614
1615 private static Class<?> toClass(Type o) {
1616 if (o instanceof GenericArrayType gat)
1617 return toClass(gat.getGenericComponentType()).arrayType();
1618 return (Class<?>)o;
1619 }
1620
1621 /**
1622 * If this {@code Class} object represents a local or anonymous
1623 * class within a constructor, returns a {@link
1624 * java.lang.reflect.Constructor Constructor} object representing
1625 * the immediately enclosing constructor of the underlying
1626 * class. Returns {@code null} otherwise. In particular, this
1627 * method returns {@code null} if the underlying class is a local
1628 * or anonymous class immediately enclosed by a class or
1629 * interface declaration, instance initializer or static initializer.
1630 *
1631 * @return the immediately enclosing constructor of the underlying class, if
1632 * that class is a local or anonymous class; otherwise {@code null}.
1633 *
1634 * @since 1.5
1635 */
1636 public Constructor<?> getEnclosingConstructor() {
1637 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1638
1639 if (enclosingInfo == null)
1640 return null;
1641 else {
1642 if (!enclosingInfo.isConstructor())
1643 return null;
1644
1645 ConstructorRepository typeInfo = ConstructorRepository.make(enclosingInfo.getDescriptor(),
1646 getFactory());
1647 Type [] parameterTypes = typeInfo.getParameterTypes();
1648 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length];
1649
1650 // Convert Types to Classes; returned types *should*
1651 // be class objects since the methodDescriptor's used
1652 // don't have generics information
1653 for (int i = 0; i < parameterClasses.length; i++)
1654 parameterClasses[i] = toClass(parameterTypes[i]);
1655
1656
1657 final Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass();
1658 Constructor<?>[] candidates = enclosingCandidate
1659 .privateGetDeclaredConstructors(false);
1660 /*
1661 * Loop over all declared constructors; match number
1662 * of and type of parameters.
1663 */
1664 ReflectionFactory fact = getReflectionFactory();
1665 for (Constructor<?> c : candidates) {
1666 if (arrayContentsEq(parameterClasses,
1667 fact.getExecutableSharedParameterTypes(c))) {
1668 return fact.copyConstructor(c);
1669 }
1670 }
1671
1672 throw new InternalError("Enclosing constructor not found");
1673 }
1674 }
1675
1676
1677 /**
1678 * If the class or interface represented by this {@code Class} object
1679 * is a member of another class, returns the {@code Class} object
1680 * representing the class in which it was declared. This method returns
1681 * null if this class or interface is not a member of any other class. If
1682 * this {@code Class} object represents an array class, a primitive
1683 * type, or void, then this method returns null.
1684 *
1685 * @return the declaring class for this class
1686 * @since 1.1
1687 */
1688 public Class<?> getDeclaringClass() {
1689 return getDeclaringClass0();
1690 }
1691
1692 private native Class<?> getDeclaringClass0();
1693
1694
1695 /**
1696 * Returns the immediately enclosing class of the underlying
1697 * class. If the underlying class is a top level class this
1698 * method returns {@code null}.
1699 * @return the immediately enclosing class of the underlying class
1700 * @since 1.5
1701 */
1702 public Class<?> getEnclosingClass() {
1703 // There are five kinds of classes (or interfaces):
1704 // a) Top level classes
1705 // b) Nested classes (static member classes)
1706 // c) Inner classes (non-static member classes)
1707 // d) Local classes (named classes declared within a method)
1708 // e) Anonymous classes
1709
1710
1711 // JVM Spec 4.7.7: A class must have an EnclosingMethod
1712 // attribute if and only if it is a local class or an
1713 // anonymous class.
1714 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1715 Class<?> enclosingCandidate;
1716
1717 if (enclosingInfo == null) {
1718 // This is a top level or a nested class or an inner class (a, b, or c)
1719 enclosingCandidate = getDeclaringClass0();
1720 } else {
1721 Class<?> enclosingClass = enclosingInfo.getEnclosingClass();
1722 // This is a local class or an anonymous class (d or e)
1723 if (enclosingClass == this || enclosingClass == null)
1724 throw new InternalError("Malformed enclosing method information");
1725 else
1726 enclosingCandidate = enclosingClass;
1727 }
1728 return enclosingCandidate;
1729 }
1730
1731 /**
1732 * Returns the simple name of the underlying class as given in the
1733 * source code. An empty string is returned if the underlying class is
1734 * {@linkplain #isAnonymousClass() anonymous}.
1735 * A {@linkplain #isSynthetic() synthetic class}, one not present
1736 * in source code, can have a non-empty name including special
1737 * characters, such as "{@code $}".
1738 *
1739 * <p>The simple name of an {@linkplain #isArray() array class} is the simple name of the
1740 * component type with "[]" appended. In particular the simple
1741 * name of an array class whose component type is anonymous is "[]".
1742 *
1743 * @return the simple name of the underlying class
1744 * @since 1.5
1745 */
1746 public String getSimpleName() {
1747 ReflectionData<T> rd = reflectionData();
1748 String simpleName = rd.simpleName;
1749 if (simpleName == null) {
1750 rd.simpleName = simpleName = getSimpleName0();
1751 }
1752 return simpleName;
1753 }
1754
1755 private String getSimpleName0() {
1756 if (isArray()) {
1757 return getComponentType().getSimpleName().concat("[]");
1758 }
1759 String simpleName = getSimpleBinaryName();
1760 if (simpleName == null) { // top level class
1761 simpleName = getName();
1762 simpleName = simpleName.substring(simpleName.lastIndexOf('.') + 1); // strip the package name
1763 }
1764 return simpleName;
1765 }
1766
1767 /**
1768 * Return an informative string for the name of this class or interface.
1769 *
1770 * @return an informative string for the name of this class or interface
1771 * @since 1.8
1772 */
1773 public String getTypeName() {
1774 if (isArray()) {
1775 try {
1776 Class<?> cl = this;
1777 int dimensions = 0;
1778 do {
1779 dimensions++;
1780 cl = cl.getComponentType();
1781 } while (cl.isArray());
1782 return cl.getName().concat("[]".repeat(dimensions));
1783 } catch (Throwable e) { /*FALLTHRU*/ }
1784 }
1785 return getName();
1786 }
1787
1788 /**
1789 * Returns the canonical name of the underlying class as
1790 * defined by <cite>The Java Language Specification</cite>.
1791 * Returns {@code null} if the underlying class does not have a canonical
1792 * name. Classes without canonical names include:
1793 * <ul>
1794 * <li>a {@linkplain #isLocalClass() local class}
1795 * <li>a {@linkplain #isAnonymousClass() anonymous class}
1796 * <li>a {@linkplain #isHidden() hidden class}
1797 * <li>an array whose component type does not have a canonical name</li>
1798 * </ul>
1799 *
1800 * The canonical name for a primitive class is the keyword for the
1801 * corresponding primitive type ({@code byte}, {@code short},
1802 * {@code char}, {@code int}, and so on).
1803 *
1804 * <p>An array type has a canonical name if and only if its
1805 * component type has a canonical name. When an array type has a
1806 * canonical name, it is equal to the canonical name of the
1807 * component type followed by "{@code []}".
1808 *
1809 * @return the canonical name of the underlying class if it exists, and
1810 * {@code null} otherwise.
1811 * @jls 6.7 Fully Qualified Names and Canonical Names
1812 * @since 1.5
1813 */
1814 public String getCanonicalName() {
1815 ReflectionData<T> rd = reflectionData();
1816 String canonicalName = rd.canonicalName;
1817 if (canonicalName == null) {
1818 rd.canonicalName = canonicalName = getCanonicalName0();
1819 }
1820 return canonicalName == ReflectionData.NULL_SENTINEL? null : canonicalName;
1821 }
1822
1823 private String getCanonicalName0() {
1824 if (isArray()) {
1825 String canonicalName = getComponentType().getCanonicalName();
1826 if (canonicalName != null)
1827 return canonicalName.concat("[]");
1828 else
1829 return ReflectionData.NULL_SENTINEL;
1830 }
1831 if (isHidden() || isLocalOrAnonymousClass())
1832 return ReflectionData.NULL_SENTINEL;
1833 Class<?> enclosingClass = getEnclosingClass();
1834 if (enclosingClass == null) { // top level class
1835 return getName();
1836 } else {
1837 String enclosingName = enclosingClass.getCanonicalName();
1838 if (enclosingName == null)
1839 return ReflectionData.NULL_SENTINEL;
1840 String simpleName = getSimpleName();
1841 return new StringBuilder(enclosingName.length() + simpleName.length() + 1)
1842 .append(enclosingName)
1843 .append('.')
1844 .append(simpleName)
1845 .toString();
1846 }
1847 }
1848
1849 /**
1850 * Returns {@code true} if and only if the underlying class
1851 * is an anonymous class.
1852 *
1853 * @apiNote
1854 * An anonymous class is not a {@linkplain #isHidden() hidden class}.
1855 *
1856 * @return {@code true} if and only if this class is an anonymous class.
1857 * @since 1.5
1858 * @jls 15.9.5 Anonymous Class Declarations
1859 */
1860 public boolean isAnonymousClass() {
1861 return !isArray() && isLocalOrAnonymousClass() &&
1862 getSimpleBinaryName0() == null;
1863 }
1864
1865 /**
1866 * Returns {@code true} if and only if the underlying class
1867 * is a local class.
1868 *
1869 * @return {@code true} if and only if this class is a local class.
1870 * @since 1.5
1871 * @jls 14.3 Local Class and Interface Declarations
1872 */
1873 public boolean isLocalClass() {
1874 return isLocalOrAnonymousClass() &&
1875 (isArray() || getSimpleBinaryName0() != null);
1876 }
1877
1878 /**
1879 * Returns {@code true} if and only if the underlying class
1880 * is a member class.
1881 *
1882 * @return {@code true} if and only if this class is a member class.
1883 * @since 1.5
1884 * @jls 8.5 Member Class and Interface Declarations
1885 */
1886 public boolean isMemberClass() {
1887 return !isLocalOrAnonymousClass() && getDeclaringClass0() != null;
1888 }
1889
1890 /**
1891 * Returns the "simple binary name" of the underlying class, i.e.,
1892 * the binary name without the leading enclosing class name.
1893 * Returns {@code null} if the underlying class is a top level
1894 * class.
1895 */
1896 private String getSimpleBinaryName() {
1897 if (isTopLevelClass())
1898 return null;
1899 String name = getSimpleBinaryName0();
1900 if (name == null) // anonymous class
1901 return "";
1902 return name;
1903 }
1904
1905 private native String getSimpleBinaryName0();
1906
1907 /**
1908 * Returns {@code true} if this is a top level class. Returns {@code false}
1909 * otherwise.
1910 */
1911 private boolean isTopLevelClass() {
1912 return !isLocalOrAnonymousClass() && getDeclaringClass0() == null;
1913 }
1914
1915 /**
1916 * Returns {@code true} if this is a local class or an anonymous
1917 * class. Returns {@code false} otherwise.
1918 */
1919 private boolean isLocalOrAnonymousClass() {
1920 // JVM Spec 4.7.7: A class must have an EnclosingMethod
1921 // attribute if and only if it is a local class or an
1922 // anonymous class.
1923 return hasEnclosingMethodInfo();
1924 }
1925
1926 private boolean hasEnclosingMethodInfo() {
1927 Object[] enclosingInfo = getEnclosingMethod0();
1928 if (enclosingInfo != null) {
1929 EnclosingMethodInfo.validate(enclosingInfo);
1930 return true;
1931 }
1932 return false;
1933 }
1934
1935 /**
1936 * Returns an array containing {@code Class} objects representing all
1937 * the public classes and interfaces that are members of the class
1938 * represented by this {@code Class} object. This includes public
1939 * class and interface members inherited from superclasses and public class
1940 * and interface members declared by the class. This method returns an
1941 * array of length 0 if this {@code Class} object has no public member
1942 * classes or interfaces. This method also returns an array of length 0 if
1943 * this {@code Class} object represents a primitive type, an array
1944 * class, or void.
1945 *
1946 * @return the array of {@code Class} objects representing the public
1947 * members of this class
1948 * @since 1.1
1949 */
1950 public Class<?>[] getClasses() {
1951 List<Class<?>> list = new ArrayList<>();
1952 Class<?> currentClass = Class.this;
1953 while (currentClass != null) {
1954 for (Class<?> m : currentClass.getDeclaredClasses()) {
1955 if (Modifier.isPublic(m.getModifiers())) {
1956 list.add(m);
1957 }
1958 }
1959 currentClass = currentClass.getSuperclass();
1960 }
1961 return list.toArray(new Class<?>[0]);
1962 }
1963
1964
1965 /**
1966 * Returns an array containing {@code Field} objects reflecting all
1967 * the accessible public fields of the class or interface represented by
1968 * this {@code Class} object.
1969 *
1970 * <p> If this {@code Class} object represents a class or interface with
1971 * no accessible public fields, then this method returns an array of length
1972 * 0.
1973 *
1974 * <p> If this {@code Class} object represents a class, then this method
1975 * returns the public fields of the class and of all its superclasses and
1976 * superinterfaces.
1977 *
1978 * <p> If this {@code Class} object represents an interface, then this
1979 * method returns the fields of the interface and of all its
1980 * superinterfaces.
1981 *
1982 * <p> If this {@code Class} object represents an array type, a primitive
1983 * type, or void, then this method returns an array of length 0.
1984 *
1985 * <p> The elements in the returned array are not sorted and are not in any
1986 * particular order.
1987 *
1988 * @return the array of {@code Field} objects representing the
1989 * public fields
1990 *
1991 * @since 1.1
1992 * @jls 8.2 Class Members
1993 * @jls 8.3 Field Declarations
1994 */
1995 public Field[] getFields() {
1996 return copyFields(privateGetPublicFields());
1997 }
1998
1999
2000 /**
2001 * Returns an array containing {@code Method} objects reflecting all the
2002 * public methods of the class or interface represented by this {@code
2003 * Class} object, including those declared by the class or interface and
2004 * those inherited from superclasses and superinterfaces.
2005 *
2006 * <p> If this {@code Class} object represents an array type, then the
2007 * returned array has a {@code Method} object for each of the public
2008 * methods inherited by the array type from {@code Object}. It does not
2009 * contain a {@code Method} object for {@code clone()}.
2010 *
2011 * <p> If this {@code Class} object represents an interface then the
2012 * returned array does not contain any implicitly declared methods from
2013 * {@code Object}. Therefore, if no methods are explicitly declared in
2014 * this interface or any of its superinterfaces then the returned array
2015 * has length 0. (Note that a {@code Class} object which represents a class
2016 * always has public methods, inherited from {@code Object}.)
2017 *
2018 * <p> The returned array never contains methods with names {@value
2019 * ConstantDescs#INIT_NAME} or {@value ConstantDescs#CLASS_INIT_NAME}.
2020 *
2021 * <p> The elements in the returned array are not sorted and are not in any
2022 * particular order.
2023 *
2024 * <p> Generally, the result is computed as with the following 4 step algorithm.
2025 * Let C be the class or interface represented by this {@code Class} object:
2026 * <ol>
2027 * <li> A union of methods is composed of:
2028 * <ol type="a">
2029 * <li> C's declared public instance and static methods as returned by
2030 * {@link #getDeclaredMethods()} and filtered to include only public
2031 * methods.</li>
2032 * <li> If C is a class other than {@code Object}, then include the result
2033 * of invoking this algorithm recursively on the superclass of C.</li>
2034 * <li> Include the results of invoking this algorithm recursively on all
2035 * direct superinterfaces of C, but include only instance methods.</li>
2036 * </ol></li>
2037 * <li> Union from step 1 is partitioned into subsets of methods with same
2038 * signature (name, parameter types) and return type.</li>
2039 * <li> Within each such subset only the most specific methods are selected.
2040 * Let method M be a method from a set of methods with same signature
2041 * and return type. M is most specific if there is no such method
2042 * N != M from the same set, such that N is more specific than M.
2043 * N is more specific than M if:
2044 * <ol type="a">
2045 * <li> N is declared by a class and M is declared by an interface; or</li>
2046 * <li> N and M are both declared by classes or both by interfaces and
2047 * N's declaring type is the same as or a subtype of M's declaring type
2048 * (clearly, if M's and N's declaring types are the same type, then
2049 * M and N are the same method).</li>
2050 * </ol></li>
2051 * <li> The result of this algorithm is the union of all selected methods from
2052 * step 3.</li>
2053 * </ol>
2054 *
2055 * @apiNote There may be more than one method with a particular name
2056 * and parameter types in a class because while the Java language forbids a
2057 * class to declare multiple methods with the same signature but different
2058 * return types, the Java virtual machine does not. This
2059 * increased flexibility in the virtual machine can be used to
2060 * implement various language features. For example, covariant
2061 * returns can be implemented with {@linkplain
2062 * java.lang.reflect.Method#isBridge bridge methods}; the bridge
2063 * method and the overriding method would have the same
2064 * signature but different return types.
2065 *
2066 * @return the array of {@code Method} objects representing the
2067 * public methods of this class
2068 *
2069 * @jls 8.2 Class Members
2070 * @jls 8.4 Method Declarations
2071 * @since 1.1
2072 */
2073 public Method[] getMethods() {
2074 return copyMethods(privateGetPublicMethods());
2075 }
2076
2077
2078 /**
2079 * Returns an array containing {@code Constructor} objects reflecting
2080 * all the public constructors of the class represented by this
2081 * {@code Class} object. An array of length 0 is returned if the
2082 * class has no public constructors, or if the class is an array class, or
2083 * if the class reflects a primitive type or void.
2084 *
2085 * @apiNote
2086 * While this method returns an array of {@code
2087 * Constructor<T>} objects (that is an array of constructors from
2088 * this class), the return type of this method is {@code
2089 * Constructor<?>[]} and <em>not</em> {@code Constructor<T>[]} as
2090 * might be expected. This less informative return type is
2091 * necessary since after being returned from this method, the
2092 * array could be modified to hold {@code Constructor} objects for
2093 * different classes, which would violate the type guarantees of
2094 * {@code Constructor<T>[]}.
2095 *
2096 * @return the array of {@code Constructor} objects representing the
2097 * public constructors of this class
2098 *
2099 * @see #getDeclaredConstructors()
2100 * @since 1.1
2101 */
2102 public Constructor<?>[] getConstructors() {
2103 return copyConstructors(privateGetDeclaredConstructors(true));
2104 }
2105
2106
2107 /**
2108 * Returns a {@code Field} object that reflects the specified public member
2109 * field of the class or interface represented by this {@code Class}
2110 * object. The {@code name} parameter is a {@code String} specifying the
2111 * simple name of the desired field.
2112 *
2113 * <p> The field to be reflected is determined by the algorithm that
2114 * follows. Let C be the class or interface represented by this {@code Class} object:
2115 *
2116 * <OL>
2117 * <LI> If C declares a public field with the name specified, that is the
2118 * field to be reflected.</LI>
2119 * <LI> If no field was found in step 1 above, this algorithm is applied
2120 * recursively to each direct superinterface of C. The direct
2121 * superinterfaces are searched in the order they were declared.</LI>
2122 * <LI> If no field was found in steps 1 and 2 above, and C has a
2123 * superclass S, then this algorithm is invoked recursively upon S.
2124 * If C has no superclass, then a {@code NoSuchFieldException}
2125 * is thrown.</LI>
2126 * </OL>
2127 *
2128 * <p> If this {@code Class} object represents an array type, then this
2129 * method does not find the {@code length} field of the array type.
2130 *
2131 * @param name the field name
2132 * @return the {@code Field} object of this class specified by
2133 * {@code name}
2134 * @throws NoSuchFieldException if a field with the specified name is
2135 * not found.
2136 * @throws NullPointerException if {@code name} is {@code null}
2137 *
2138 * @since 1.1
2139 * @jls 8.2 Class Members
2140 * @jls 8.3 Field Declarations
2141 */
2142 public Field getField(String name) throws NoSuchFieldException {
2143 Objects.requireNonNull(name);
2144 Field field = getField0(name);
2145 if (field == null) {
2146 throw new NoSuchFieldException(name);
2147 }
2148 return getReflectionFactory().copyField(field);
2149 }
2150
2151
2152 /**
2153 * Returns a {@code Method} object that reflects the specified public
2154 * member method of the class or interface represented by this
2155 * {@code Class} object. The {@code name} parameter is a
2156 * {@code String} specifying the simple name of the desired method. The
2157 * {@code parameterTypes} parameter is an array of {@code Class}
2158 * objects that identify the method's formal parameter types, in declared
2159 * order. If {@code parameterTypes} is {@code null}, it is
2160 * treated as if it were an empty array.
2161 *
2162 * <p> If this {@code Class} object represents an array type, then this
2163 * method finds any public method inherited by the array type from
2164 * {@code Object} except method {@code clone()}.
2165 *
2166 * <p> If this {@code Class} object represents an interface then this
2167 * method does not find any implicitly declared method from
2168 * {@code Object}. Therefore, if no methods are explicitly declared in
2169 * this interface or any of its superinterfaces, then this method does not
2170 * find any method.
2171 *
2172 * <p> This method does not find any method with name {@value
2173 * ConstantDescs#INIT_NAME} or {@value ConstantDescs#CLASS_INIT_NAME}.
2174 *
2175 * <p> Generally, the method to be reflected is determined by the 4 step
2176 * algorithm that follows.
2177 * Let C be the class or interface represented by this {@code Class} object:
2178 * <ol>
2179 * <li> A union of methods is composed of:
2180 * <ol type="a">
2181 * <li> C's declared public instance and static methods as returned by
2182 * {@link #getDeclaredMethods()} and filtered to include only public
2183 * methods that match given {@code name} and {@code parameterTypes}</li>
2184 * <li> If C is a class other than {@code Object}, then include the result
2185 * of invoking this algorithm recursively on the superclass of C.</li>
2186 * <li> Include the results of invoking this algorithm recursively on all
2187 * direct superinterfaces of C, but include only instance methods.</li>
2188 * </ol></li>
2189 * <li> This union is partitioned into subsets of methods with same
2190 * return type (the selection of methods from step 1 also guarantees that
2191 * they have the same method name and parameter types).</li>
2192 * <li> Within each such subset only the most specific methods are selected.
2193 * Let method M be a method from a set of methods with same VM
2194 * signature (return type, name, parameter types).
2195 * M is most specific if there is no such method N != M from the same
2196 * set, such that N is more specific than M. N is more specific than M
2197 * if:
2198 * <ol type="a">
2199 * <li> N is declared by a class and M is declared by an interface; or</li>
2200 * <li> N and M are both declared by classes or both by interfaces and
2201 * N's declaring type is the same as or a subtype of M's declaring type
2202 * (clearly, if M's and N's declaring types are the same type, then
2203 * M and N are the same method).</li>
2204 * </ol></li>
2205 * <li> The result of this algorithm is chosen arbitrarily from the methods
2206 * with most specific return type among all selected methods from step 3.
2207 * Let R be a return type of a method M from the set of all selected methods
2208 * from step 3. M is a method with most specific return type if there is
2209 * no such method N != M from the same set, having return type S != R,
2210 * such that S is a subtype of R as determined by
2211 * R.class.{@link #isAssignableFrom}(S.class).
2212 * </ol>
2213 *
2214 * @apiNote There may be more than one method with matching name and
2215 * parameter types in a class because while the Java language forbids a
2216 * class to declare multiple methods with the same signature but different
2217 * return types, the Java virtual machine does not. This
2218 * increased flexibility in the virtual machine can be used to
2219 * implement various language features. For example, covariant
2220 * returns can be implemented with {@linkplain
2221 * java.lang.reflect.Method#isBridge bridge methods}; the bridge
2222 * method and the overriding method would have the same
2223 * signature but different return types. This method would return the
2224 * overriding method as it would have a more specific return type.
2225 *
2226 * @param name the name of the method
2227 * @param parameterTypes the list of parameters
2228 * @return the {@code Method} object that matches the specified
2229 * {@code name} and {@code parameterTypes}
2230 * @throws NoSuchMethodException if a matching method is not found
2231 * or if the name is {@value ConstantDescs#INIT_NAME} or
2232 * {@value ConstantDescs#CLASS_INIT_NAME}.
2233 * @throws NullPointerException if {@code name} is {@code null}
2234 *
2235 * @jls 8.2 Class Members
2236 * @jls 8.4 Method Declarations
2237 * @since 1.1
2238 */
2239 public Method getMethod(String name, Class<?>... parameterTypes)
2240 throws NoSuchMethodException {
2241 Objects.requireNonNull(name);
2242 Method method = getMethod0(name, parameterTypes);
2243 if (method == null) {
2244 throw new NoSuchMethodException(methodToString(name, parameterTypes));
2245 }
2246 return getReflectionFactory().copyMethod(method);
2247 }
2248
2249 /**
2250 * Returns a {@code Constructor} object that reflects the specified
2251 * public constructor of the class represented by this {@code Class}
2252 * object. The {@code parameterTypes} parameter is an array of
2253 * {@code Class} objects that identify the constructor's formal
2254 * parameter types, in declared order.
2255 *
2256 * If this {@code Class} object represents an inner class
2257 * declared in a non-static context, the formal parameter types
2258 * include the explicit enclosing instance as the first parameter.
2259 *
2260 * <p> The constructor to reflect is the public constructor of the class
2261 * represented by this {@code Class} object whose formal parameter
2262 * types match those specified by {@code parameterTypes}.
2263 *
2264 * @param parameterTypes the parameter array
2265 * @return the {@code Constructor} object of the public constructor that
2266 * matches the specified {@code parameterTypes}
2267 * @throws NoSuchMethodException if a matching constructor is not found,
2268 * including when this {@code Class} object represents
2269 * an interface, a primitive type, an array class, or void.
2270 *
2271 * @see #getDeclaredConstructor(Class[])
2272 * @since 1.1
2273 */
2274 public Constructor<T> getConstructor(Class<?>... parameterTypes)
2275 throws NoSuchMethodException {
2276 return getReflectionFactory().copyConstructor(
2277 getConstructor0(parameterTypes, Member.PUBLIC));
2278 }
2279
2280
2281 /**
2282 * Returns an array of {@code Class} objects reflecting all the
2283 * classes and interfaces declared as members of the class represented by
2284 * this {@code Class} object. This includes public, protected, default
2285 * (package) access, and private classes and interfaces declared by the
2286 * class, but excludes inherited classes and interfaces. This method
2287 * returns an array of length 0 if the class declares no classes or
2288 * interfaces as members, or if this {@code Class} object represents a
2289 * primitive type, an array class, or void.
2290 *
2291 * @return the array of {@code Class} objects representing all the
2292 * declared members of this class
2293 *
2294 * @since 1.1
2295 * @jls 8.5 Member Class and Interface Declarations
2296 */
2297 public Class<?>[] getDeclaredClasses() {
2298 return getDeclaredClasses0();
2299 }
2300
2301
2302 /**
2303 * Returns an array of {@code Field} objects reflecting all the fields
2304 * declared by the class or interface represented by this
2305 * {@code Class} object. This includes public, protected, default
2306 * (package) access, and private fields, but excludes inherited fields.
2307 *
2308 * <p> If this {@code Class} object represents a class or interface with no
2309 * declared fields, then this method returns an array of length 0.
2310 *
2311 * <p> If this {@code Class} object represents an array type, a primitive
2312 * type, or void, then this method returns an array of length 0.
2313 *
2314 * <p> The elements in the returned array are not sorted and are not in any
2315 * particular order.
2316 *
2317 * @return the array of {@code Field} objects representing all the
2318 * declared fields of this class
2319 *
2320 * @since 1.1
2321 * @jls 8.2 Class Members
2322 * @jls 8.3 Field Declarations
2323 */
2324 public Field[] getDeclaredFields() {
2325 return copyFields(privateGetDeclaredFields(false));
2326 }
2327
2328 /**
2329 * Returns an array of {@code RecordComponent} objects representing all the
2330 * record components of this record class, or {@code null} if this class is
2331 * not a record class.
2332 *
2333 * <p> The components are returned in the same order that they are declared
2334 * in the record header. The array is empty if this record class has no
2335 * components. If the class is not a record class, that is {@link
2336 * #isRecord()} returns {@code false}, then this method returns {@code null}.
2337 * Conversely, if {@link #isRecord()} returns {@code true}, then this method
2338 * returns a non-null value.
2339 *
2340 * @apiNote
2341 * <p> The following method can be used to find the record canonical constructor:
2342 *
2343 * {@snippet lang="java" :
2344 * static <T extends Record> Constructor<T> getCanonicalConstructor(Class<T> cls)
2345 * throws NoSuchMethodException {
2346 * Class<?>[] paramTypes =
2347 * Arrays.stream(cls.getRecordComponents())
2348 * .map(RecordComponent::getType)
2349 * .toArray(Class<?>[]::new);
2350 * return cls.getDeclaredConstructor(paramTypes);
2351 * }}
2352 *
2353 * @return An array of {@code RecordComponent} objects representing all the
2354 * record components of this record class, or {@code null} if this
2355 * class is not a record class
2356 *
2357 * @jls 8.10 Record Classes
2358 * @since 16
2359 */
2360 public RecordComponent[] getRecordComponents() {
2361 if (!isRecord()) {
2362 return null;
2363 }
2364 return getRecordComponents0();
2365 }
2366
2367 /**
2368 * Returns an array containing {@code Method} objects reflecting all the
2369 * declared methods of the class or interface represented by this {@code
2370 * Class} object, including public, protected, default (package)
2371 * access, and private methods, but excluding inherited methods.
2372 * The declared methods may include methods <em>not</em> in the
2373 * source of the class or interface, including {@linkplain
2374 * Method#isBridge bridge methods} and other {@linkplain
2375 * Executable#isSynthetic synthetic} methods added by compilers.
2376 *
2377 * <p> If this {@code Class} object represents a class or interface that
2378 * has multiple declared methods with the same name and parameter types,
2379 * but different return types, then the returned array has a {@code Method}
2380 * object for each such method.
2381 *
2382 * <p> If this {@code Class} object represents a class or interface that
2383 * has a class initialization method {@value ConstantDescs#CLASS_INIT_NAME},
2384 * then the returned array does <em>not</em> have a corresponding {@code
2385 * Method} object.
2386 *
2387 * <p> If this {@code Class} object represents a class or interface with no
2388 * declared methods, then the returned array has length 0.
2389 *
2390 * <p> If this {@code Class} object represents an array type, a primitive
2391 * type, or void, then the returned array has length 0.
2392 *
2393 * <p> The elements in the returned array are not sorted and are not in any
2394 * particular order.
2395 *
2396 * @return the array of {@code Method} objects representing all the
2397 * declared methods of this class
2398 *
2399 * @jls 8.2 Class Members
2400 * @jls 8.4 Method Declarations
2401 * @see <a
2402 * href="{@docRoot}/java.base/java/lang/reflect/package-summary.html#LanguageJvmModel">Java
2403 * programming language and JVM modeling in core reflection</a>
2404 * @since 1.1
2405 */
2406 public Method[] getDeclaredMethods() {
2407 return copyMethods(privateGetDeclaredMethods(false));
2408 }
2409
2410 /**
2411 * Returns an array of {@code Constructor} objects reflecting all the
2412 * constructors implicitly or explicitly declared by the class represented by this
2413 * {@code Class} object. These are public, protected, default
2414 * (package) access, and private constructors. The elements in the array
2415 * returned are not sorted and are not in any particular order. If the
2416 * class has a default constructor (JLS {@jls 8.8.9}), it is included in the returned array.
2417 * If a record class has a canonical constructor (JLS {@jls
2418 * 8.10.4.1}, {@jls 8.10.4.2}), it is included in the returned array.
2419 *
2420 * This method returns an array of length 0 if this {@code Class}
2421 * object represents an interface, a primitive type, an array class, or
2422 * void.
2423 *
2424 * @return the array of {@code Constructor} objects representing all the
2425 * declared constructors of this class
2426 *
2427 * @since 1.1
2428 * @see #getConstructors()
2429 * @jls 8.8 Constructor Declarations
2430 */
2431 public Constructor<?>[] getDeclaredConstructors() {
2432 return copyConstructors(privateGetDeclaredConstructors(false));
2433 }
2434
2435
2436 /**
2437 * Returns a {@code Field} object that reflects the specified declared
2438 * field of the class or interface represented by this {@code Class}
2439 * object. The {@code name} parameter is a {@code String} that specifies
2440 * the simple name of the desired field.
2441 *
2442 * <p> If this {@code Class} object represents an array type, then this
2443 * method does not find the {@code length} field of the array type.
2444 *
2445 * @param name the name of the field
2446 * @return the {@code Field} object for the specified field in this
2447 * class
2448 * @throws NoSuchFieldException if a field with the specified name is
2449 * not found.
2450 * @throws NullPointerException if {@code name} is {@code null}
2451 *
2452 * @since 1.1
2453 * @jls 8.2 Class Members
2454 * @jls 8.3 Field Declarations
2455 */
2456 public Field getDeclaredField(String name) throws NoSuchFieldException {
2457 Objects.requireNonNull(name);
2458 Field field = searchFields(privateGetDeclaredFields(false), name);
2459 if (field == null) {
2460 throw new NoSuchFieldException(name);
2461 }
2462 return getReflectionFactory().copyField(field);
2463 }
2464
2465
2466 /**
2467 * Returns a {@code Method} object that reflects the specified
2468 * declared method of the class or interface represented by this
2469 * {@code Class} object. The {@code name} parameter is a
2470 * {@code String} that specifies the simple name of the desired
2471 * method, and the {@code parameterTypes} parameter is an array of
2472 * {@code Class} objects that identify the method's formal parameter
2473 * types, in declared order. If more than one method with the same
2474 * parameter types is declared in a class, and one of these methods has a
2475 * return type that is more specific than any of the others, that method is
2476 * returned; otherwise one of the methods is chosen arbitrarily. If the
2477 * name is {@value ConstantDescs#INIT_NAME} or {@value
2478 * ConstantDescs#CLASS_INIT_NAME} a {@code NoSuchMethodException}
2479 * is raised.
2480 *
2481 * <p> If this {@code Class} object represents an array type, then this
2482 * method does not find the {@code clone()} method.
2483 *
2484 * @param name the name of the method
2485 * @param parameterTypes the parameter array
2486 * @return the {@code Method} object for the method of this class
2487 * matching the specified name and parameters
2488 * @throws NoSuchMethodException if a matching method is not found.
2489 * @throws NullPointerException if {@code name} is {@code null}
2490 *
2491 * @jls 8.2 Class Members
2492 * @jls 8.4 Method Declarations
2493 * @since 1.1
2494 */
2495 public Method getDeclaredMethod(String name, Class<?>... parameterTypes)
2496 throws NoSuchMethodException {
2497 Objects.requireNonNull(name);
2498 Method method = searchMethods(privateGetDeclaredMethods(false), name, parameterTypes);
2499 if (method == null) {
2500 throw new NoSuchMethodException(methodToString(name, parameterTypes));
2501 }
2502 return getReflectionFactory().copyMethod(method);
2503 }
2504
2505 /**
2506 * Returns the list of {@code Method} objects for the declared public
2507 * methods of this class or interface that have the specified method name
2508 * and parameter types.
2509 *
2510 * @param name the name of the method
2511 * @param parameterTypes the parameter array
2512 * @return the list of {@code Method} objects for the public methods of
2513 * this class matching the specified name and parameters
2514 */
2515 List<Method> getDeclaredPublicMethods(String name, Class<?>... parameterTypes) {
2516 Method[] methods = privateGetDeclaredMethods(/* publicOnly */ true);
2517 ReflectionFactory factory = getReflectionFactory();
2518 List<Method> result = new ArrayList<>();
2519 for (Method method : methods) {
2520 if (method.getName().equals(name)
2521 && Arrays.equals(
2522 factory.getExecutableSharedParameterTypes(method),
2523 parameterTypes)) {
2524 result.add(factory.copyMethod(method));
2525 }
2526 }
2527 return result;
2528 }
2529
2530 /**
2531 * Returns the most specific {@code Method} object of this class, super class or
2532 * interface that have the specified method name and parameter types.
2533 *
2534 * @param publicOnly true if only public methods are examined, otherwise all methods
2535 * @param name the name of the method
2536 * @param parameterTypes the parameter array
2537 * @return the {@code Method} object for the method found from this class matching
2538 * the specified name and parameters, or null if not found
2539 */
2540 Method findMethod(boolean publicOnly, String name, Class<?>... parameterTypes) {
2541 PublicMethods.MethodList res = getMethodsRecursive(name, parameterTypes, true, publicOnly);
2542 return res == null ? null : getReflectionFactory().copyMethod(res.getMostSpecific());
2543 }
2544
2545 /**
2546 * Returns a {@code Constructor} object that reflects the specified
2547 * constructor of the class represented by this
2548 * {@code Class} object. The {@code parameterTypes} parameter is
2549 * an array of {@code Class} objects that identify the constructor's
2550 * formal parameter types, in declared order.
2551 *
2552 * If this {@code Class} object represents an inner class
2553 * declared in a non-static context, the formal parameter types
2554 * include the explicit enclosing instance as the first parameter.
2555 *
2556 * @param parameterTypes the parameter array
2557 * @return The {@code Constructor} object for the constructor with the
2558 * specified parameter list
2559 * @throws NoSuchMethodException if a matching constructor is not found,
2560 * including when this {@code Class} object represents
2561 * an interface, a primitive type, an array class, or void.
2562 *
2563 * @see #getConstructor(Class[])
2564 * @since 1.1
2565 */
2566 public Constructor<T> getDeclaredConstructor(Class<?>... parameterTypes)
2567 throws NoSuchMethodException {
2568 return getReflectionFactory().copyConstructor(
2569 getConstructor0(parameterTypes, Member.DECLARED));
2570 }
2571
2572 /**
2573 * Finds a resource with a given name.
2574 *
2575 * <p> If this class is in a named {@link Module Module} then this method
2576 * will attempt to find the resource in the module. This is done by
2577 * delegating to the module's class loader {@link
2578 * ClassLoader#findResource(String,String) findResource(String,String)}
2579 * method, invoking it with the module name and the absolute name of the
2580 * resource. Resources in named modules are subject to the rules for
2581 * encapsulation specified in the {@code Module} {@link
2582 * Module#getResourceAsStream getResourceAsStream} method and so this
2583 * method returns {@code null} when the resource is a
2584 * non-"{@code .class}" resource in a package that is not open to the
2585 * caller's module.
2586 *
2587 * <p> Otherwise, if this class is not in a named module then the rules for
2588 * searching resources associated with a given class are implemented by the
2589 * defining {@linkplain ClassLoader class loader} of the class. This method
2590 * delegates to this {@code Class} object's class loader.
2591 * If this {@code Class} object was loaded by the bootstrap class loader,
2592 * the method delegates to {@link ClassLoader#getSystemResourceAsStream}.
2593 *
2594 * <p> Before delegation, an absolute resource name is constructed from the
2595 * given resource name using this algorithm:
2596 *
2597 * <ul>
2598 *
2599 * <li> If the {@code name} begins with a {@code '/'}
2600 * (<code>'\u002f'</code>), then the absolute name of the resource is the
2601 * portion of the {@code name} following the {@code '/'}.
2602 *
2603 * <li> Otherwise, the absolute name is of the following form:
2604 *
2605 * <blockquote>
2606 * {@code modified_package_name/name}
2607 * </blockquote>
2608 *
2609 * <p> Where the {@code modified_package_name} is the package name of this
2610 * object with {@code '/'} substituted for {@code '.'}
2611 * (<code>'\u002e'</code>).
2612 *
2613 * </ul>
2614 *
2615 * @param name name of the desired resource
2616 * @return A {@link java.io.InputStream} object; {@code null} if no
2617 * resource with this name is found, or the resource is in a package
2618 * that is not {@linkplain Module#isOpen(String, Module) open} to at
2619 * least the caller module.
2620 * @throws NullPointerException If {@code name} is {@code null}
2621 *
2622 * @see Module#getResourceAsStream(String)
2623 * @since 1.1
2624 */
2625 @CallerSensitive
2626 public InputStream getResourceAsStream(String name) {
2627 name = resolveName(name);
2628
2629 Module thisModule = getModule();
2630 if (thisModule.isNamed()) {
2631 // check if resource can be located by caller
2632 if (Resources.canEncapsulate(name)
2633 && !isOpenToCaller(name, Reflection.getCallerClass())) {
2634 return null;
2635 }
2636
2637 // resource not encapsulated or in package open to caller
2638 String mn = thisModule.getName();
2639 ClassLoader cl = classLoader;
2640 try {
2641
2642 // special-case built-in class loaders to avoid the
2643 // need for a URL connection
2644 if (cl == null) {
2645 return BootLoader.findResourceAsStream(mn, name);
2646 } else if (cl instanceof BuiltinClassLoader bcl) {
2647 return bcl.findResourceAsStream(mn, name);
2648 } else {
2649 URL url = cl.findResource(mn, name);
2650 return (url != null) ? url.openStream() : null;
2651 }
2652
2653 } catch (IOException | SecurityException e) {
2654 return null;
2655 }
2656 }
2657
2658 // unnamed module
2659 ClassLoader cl = classLoader;
2660 if (cl == null) {
2661 return ClassLoader.getSystemResourceAsStream(name);
2662 } else {
2663 return cl.getResourceAsStream(name);
2664 }
2665 }
2666
2667 /**
2668 * Finds a resource with a given name.
2669 *
2670 * <p> If this class is in a named {@link Module Module} then this method
2671 * will attempt to find the resource in the module. This is done by
2672 * delegating to the module's class loader {@link
2673 * ClassLoader#findResource(String,String) findResource(String,String)}
2674 * method, invoking it with the module name and the absolute name of the
2675 * resource. Resources in named modules are subject to the rules for
2676 * encapsulation specified in the {@code Module} {@link
2677 * Module#getResourceAsStream getResourceAsStream} method and so this
2678 * method returns {@code null} when the resource is a
2679 * non-"{@code .class}" resource in a package that is not open to the
2680 * caller's module.
2681 *
2682 * <p> Otherwise, if this class is not in a named module then the rules for
2683 * searching resources associated with a given class are implemented by the
2684 * defining {@linkplain ClassLoader class loader} of the class. This method
2685 * delegates to this {@code Class} object's class loader.
2686 * If this {@code Class} object was loaded by the bootstrap class loader,
2687 * the method delegates to {@link ClassLoader#getSystemResource}.
2688 *
2689 * <p> Before delegation, an absolute resource name is constructed from the
2690 * given resource name using this algorithm:
2691 *
2692 * <ul>
2693 *
2694 * <li> If the {@code name} begins with a {@code '/'}
2695 * (<code>'\u002f'</code>), then the absolute name of the resource is the
2696 * portion of the {@code name} following the {@code '/'}.
2697 *
2698 * <li> Otherwise, the absolute name is of the following form:
2699 *
2700 * <blockquote>
2701 * {@code modified_package_name/name}
2702 * </blockquote>
2703 *
2704 * <p> Where the {@code modified_package_name} is the package name of this
2705 * object with {@code '/'} substituted for {@code '.'}
2706 * (<code>'\u002e'</code>).
2707 *
2708 * </ul>
2709 *
2710 * @param name name of the desired resource
2711 * @return A {@link java.net.URL} object; {@code null} if no resource with
2712 * this name is found, the resource cannot be located by a URL, or the
2713 * resource is in a package that is not
2714 * {@linkplain Module#isOpen(String, Module) open} to at least the caller
2715 * module.
2716 * @throws NullPointerException If {@code name} is {@code null}
2717 * @since 1.1
2718 */
2719 @CallerSensitive
2720 public URL getResource(String name) {
2721 name = resolveName(name);
2722
2723 Module thisModule = getModule();
2724 if (thisModule.isNamed()) {
2725 // check if resource can be located by caller
2726 if (Resources.canEncapsulate(name)
2727 && !isOpenToCaller(name, Reflection.getCallerClass())) {
2728 return null;
2729 }
2730
2731 // resource not encapsulated or in package open to caller
2732 String mn = thisModule.getName();
2733 ClassLoader cl = classLoader;
2734 try {
2735 if (cl == null) {
2736 return BootLoader.findResource(mn, name);
2737 } else {
2738 return cl.findResource(mn, name);
2739 }
2740 } catch (IOException ioe) {
2741 return null;
2742 }
2743 }
2744
2745 // unnamed module
2746 ClassLoader cl = classLoader;
2747 if (cl == null) {
2748 return ClassLoader.getSystemResource(name);
2749 } else {
2750 return cl.getResource(name);
2751 }
2752 }
2753
2754 /**
2755 * Returns true if a resource with the given name can be located by the
2756 * given caller. All resources in a module can be located by code in
2757 * the module. For other callers, then the package needs to be open to
2758 * the caller.
2759 */
2760 private boolean isOpenToCaller(String name, Class<?> caller) {
2761 // assert getModule().isNamed();
2762 Module thisModule = getModule();
2763 Module callerModule = (caller != null) ? caller.getModule() : null;
2764 if (callerModule != thisModule) {
2765 String pn = Resources.toPackageName(name);
2766 if (thisModule.getDescriptor().packages().contains(pn)) {
2767 if (callerModule == null) {
2768 // no caller, return true if the package is open to all modules
2769 return thisModule.isOpen(pn);
2770 }
2771 if (!thisModule.isOpen(pn, callerModule)) {
2772 // package not open to caller
2773 return false;
2774 }
2775 }
2776 }
2777 return true;
2778 }
2779
2780 private transient final ProtectionDomain protectionDomain;
2781
2782 /** Holder for the protection domain returned when the internal domain is null */
2783 private static class Holder {
2784 private static final ProtectionDomain allPermDomain;
2785 static {
2786 Permissions perms = new Permissions();
2787 perms.add(new AllPermission());
2788 allPermDomain = new ProtectionDomain(null, perms);
2789 }
2790 }
2791
2792 /**
2793 * Returns the {@code ProtectionDomain} of this class.
2794 *
2795 * @return the ProtectionDomain of this class
2796 *
2797 * @see java.security.ProtectionDomain
2798 * @since 1.2
2799 */
2800 public ProtectionDomain getProtectionDomain() {
2801 if (protectionDomain == null) {
2802 return Holder.allPermDomain;
2803 } else {
2804 return protectionDomain;
2805 }
2806 }
2807
2808 /*
2809 * Returns the Class object for the named primitive type. Type parameter T
2810 * avoids redundant casts for trusted code.
2811 */
2812 static native <T> Class<T> getPrimitiveClass(String name);
2813
2814 /**
2815 * Add a package name prefix if the name is not absolute. Remove leading "/"
2816 * if name is absolute
2817 */
2818 private String resolveName(String name) {
2819 if (!name.startsWith("/")) {
2820 String baseName = getPackageName();
2821 if (!baseName.isEmpty()) {
2822 int len = baseName.length() + 1 + name.length();
2823 StringBuilder sb = new StringBuilder(len);
2824 name = sb.append(baseName.replace('.', '/'))
2825 .append('/')
2826 .append(name)
2827 .toString();
2828 }
2829 } else {
2830 name = name.substring(1);
2831 }
2832 return name;
2833 }
2834
2835 /**
2836 * Atomic operations support.
2837 */
2838 private static class Atomic {
2839 // initialize Unsafe machinery here, since we need to call Class.class instance method
2840 // and have to avoid calling it in the static initializer of the Class class...
2841 private static final Unsafe unsafe = Unsafe.getUnsafe();
2842 // offset of Class.reflectionData instance field
2843 private static final long reflectionDataOffset
2844 = unsafe.objectFieldOffset(Class.class, "reflectionData");
2845 // offset of Class.annotationType instance field
2846 private static final long annotationTypeOffset
2847 = unsafe.objectFieldOffset(Class.class, "annotationType");
2848 // offset of Class.annotationData instance field
2849 private static final long annotationDataOffset
2850 = unsafe.objectFieldOffset(Class.class, "annotationData");
2851
2852 static <T> boolean casReflectionData(Class<?> clazz,
2853 SoftReference<ReflectionData<T>> oldData,
2854 SoftReference<ReflectionData<T>> newData) {
2855 return unsafe.compareAndSetReference(clazz, reflectionDataOffset, oldData, newData);
2856 }
2857
2858 static boolean casAnnotationType(Class<?> clazz,
2859 AnnotationType oldType,
2860 AnnotationType newType) {
2861 return unsafe.compareAndSetReference(clazz, annotationTypeOffset, oldType, newType);
2862 }
2863
2864 static boolean casAnnotationData(Class<?> clazz,
2865 AnnotationData oldData,
2866 AnnotationData newData) {
2867 return unsafe.compareAndSetReference(clazz, annotationDataOffset, oldData, newData);
2868 }
2869 }
2870
2871 /**
2872 * Reflection support.
2873 */
2874
2875 // Reflection data caches various derived names and reflective members. Cached
2876 // values may be invalidated when JVM TI RedefineClasses() is called
2877 private static class ReflectionData<T> {
2878 volatile Field[] declaredFields;
2879 volatile Field[] publicFields;
2880 volatile Method[] declaredMethods;
2881 volatile Method[] publicMethods;
2882 volatile Constructor<T>[] declaredConstructors;
2883 volatile Constructor<T>[] publicConstructors;
2884 // Intermediate results for getFields and getMethods
2885 volatile Field[] declaredPublicFields;
2886 volatile Method[] declaredPublicMethods;
2887 volatile Class<?>[] interfaces;
2888
2889 // Cached names
2890 String simpleName;
2891 String canonicalName;
2892 static final String NULL_SENTINEL = new String();
2893
2894 // Value of classRedefinedCount when we created this ReflectionData instance
2895 final int redefinedCount;
2896
2897 ReflectionData(int redefinedCount) {
2898 this.redefinedCount = redefinedCount;
2899 }
2900 }
2901
2902 private transient volatile SoftReference<ReflectionData<T>> reflectionData;
2903
2904 // Incremented by the VM on each call to JVM TI RedefineClasses()
2905 // that redefines this class or a superclass.
2906 private transient volatile int classRedefinedCount;
2907
2908 // Lazily create and cache ReflectionData
2909 private ReflectionData<T> reflectionData() {
2910 SoftReference<ReflectionData<T>> reflectionData = this.reflectionData;
2911 int classRedefinedCount = this.classRedefinedCount;
2912 ReflectionData<T> rd;
2913 if (reflectionData != null &&
2914 (rd = reflectionData.get()) != null &&
2915 rd.redefinedCount == classRedefinedCount) {
2916 return rd;
2917 }
2918 // else no SoftReference or cleared SoftReference or stale ReflectionData
2919 // -> create and replace new instance
2920 return newReflectionData(reflectionData, classRedefinedCount);
2921 }
2922
2923 private ReflectionData<T> newReflectionData(SoftReference<ReflectionData<T>> oldReflectionData,
2924 int classRedefinedCount) {
2925 while (true) {
2926 ReflectionData<T> rd = new ReflectionData<>(classRedefinedCount);
2927 // try to CAS it...
2928 if (Atomic.casReflectionData(this, oldReflectionData, new SoftReference<>(rd))) {
2929 return rd;
2930 }
2931 // else retry
2932 oldReflectionData = this.reflectionData;
2933 classRedefinedCount = this.classRedefinedCount;
2934 if (oldReflectionData != null &&
2935 (rd = oldReflectionData.get()) != null &&
2936 rd.redefinedCount == classRedefinedCount) {
2937 return rd;
2938 }
2939 }
2940 }
2941
2942 // Generic signature handling
2943 private native String getGenericSignature0();
2944
2945 // Generic info repository; lazily initialized
2946 private transient volatile ClassRepository genericInfo;
2947
2948 // accessor for factory
2949 private GenericsFactory getFactory() {
2950 // create scope and factory
2951 return CoreReflectionFactory.make(this, ClassScope.make(this));
2952 }
2953
2954 // accessor for generic info repository;
2955 // generic info is lazily initialized
2956 private ClassRepository getGenericInfo() {
2957 ClassRepository genericInfo = this.genericInfo;
2958 if (genericInfo == null) {
2959 String signature = getGenericSignature0();
2960 if (signature == null) {
2961 genericInfo = ClassRepository.NONE;
2962 } else {
2963 genericInfo = ClassRepository.make(signature, getFactory());
2964 }
2965 this.genericInfo = genericInfo;
2966 }
2967 return (genericInfo != ClassRepository.NONE) ? genericInfo : null;
2968 }
2969
2970 // Annotations handling
2971 native byte[] getRawAnnotations();
2972 // Since 1.8
2973 native byte[] getRawTypeAnnotations();
2974 static byte[] getExecutableTypeAnnotationBytes(Executable ex) {
2975 return getReflectionFactory().getExecutableTypeAnnotationBytes(ex);
2976 }
2977
2978 native ConstantPool getConstantPool();
2979
2980 //
2981 //
2982 // java.lang.reflect.Field handling
2983 //
2984 //
2985
2986 // Returns an array of "root" fields. These Field objects must NOT
2987 // be propagated to the outside world, but must instead be copied
2988 // via ReflectionFactory.copyField.
2989 private Field[] privateGetDeclaredFields(boolean publicOnly) {
2990 Field[] res;
2991 ReflectionData<T> rd = reflectionData();
2992 res = publicOnly ? rd.declaredPublicFields : rd.declaredFields;
2993 if (res != null) return res;
2994 // No cached value available; request value from VM
2995 res = Reflection.filterFields(this, getDeclaredFields0(publicOnly));
2996 if (publicOnly) {
2997 rd.declaredPublicFields = res;
2998 } else {
2999 rd.declaredFields = res;
3000 }
3001 return res;
3002 }
3003
3004 // Returns an array of "root" fields. These Field objects must NOT
3005 // be propagated to the outside world, but must instead be copied
3006 // via ReflectionFactory.copyField.
3007 private Field[] privateGetPublicFields() {
3008 Field[] res;
3009 ReflectionData<T> rd = reflectionData();
3010 res = rd.publicFields;
3011 if (res != null) return res;
3012
3013 // Use a linked hash set to ensure order is preserved and
3014 // fields from common super interfaces are not duplicated
3015 LinkedHashSet<Field> fields = new LinkedHashSet<>();
3016
3017 // Local fields
3018 addAll(fields, privateGetDeclaredFields(true));
3019
3020 // Direct superinterfaces, recursively
3021 for (Class<?> si : getInterfaces(/* cloneArray */ false)) {
3022 addAll(fields, si.privateGetPublicFields());
3023 }
3024
3025 // Direct superclass, recursively
3026 Class<?> sc = getSuperclass();
3027 if (sc != null) {
3028 addAll(fields, sc.privateGetPublicFields());
3029 }
3030
3031 res = fields.toArray(new Field[0]);
3032 rd.publicFields = res;
3033 return res;
3034 }
3035
3036 private static void addAll(Collection<Field> c, Field[] o) {
3037 for (Field f : o) {
3038 c.add(f);
3039 }
3040 }
3041
3042
3043 //
3044 //
3045 // java.lang.reflect.Constructor handling
3046 //
3047 //
3048
3049 // Returns an array of "root" constructors. These Constructor
3050 // objects must NOT be propagated to the outside world, but must
3051 // instead be copied via ReflectionFactory.copyConstructor.
3052 private Constructor<T>[] privateGetDeclaredConstructors(boolean publicOnly) {
3053 Constructor<T>[] res;
3054 ReflectionData<T> rd = reflectionData();
3055 res = publicOnly ? rd.publicConstructors : rd.declaredConstructors;
3056 if (res != null) return res;
3057 // No cached value available; request value from VM
3058 if (isInterface()) {
3059 @SuppressWarnings("unchecked")
3060 Constructor<T>[] temporaryRes = (Constructor<T>[]) new Constructor<?>[0];
3061 res = temporaryRes;
3062 } else {
3063 res = getDeclaredConstructors0(publicOnly);
3064 }
3065 if (publicOnly) {
3066 rd.publicConstructors = res;
3067 } else {
3068 rd.declaredConstructors = res;
3069 }
3070 return res;
3071 }
3072
3073 //
3074 //
3075 // java.lang.reflect.Method handling
3076 //
3077 //
3078
3079 // Returns an array of "root" methods. These Method objects must NOT
3080 // be propagated to the outside world, but must instead be copied
3081 // via ReflectionFactory.copyMethod.
3082 private Method[] privateGetDeclaredMethods(boolean publicOnly) {
3083 Method[] res;
3084 ReflectionData<T> rd = reflectionData();
3085 res = publicOnly ? rd.declaredPublicMethods : rd.declaredMethods;
3086 if (res != null) return res;
3087 // No cached value available; request value from VM
3088 res = Reflection.filterMethods(this, getDeclaredMethods0(publicOnly));
3089 if (publicOnly) {
3090 rd.declaredPublicMethods = res;
3091 } else {
3092 rd.declaredMethods = res;
3093 }
3094 return res;
3095 }
3096
3097 // Returns an array of "root" methods. These Method objects must NOT
3098 // be propagated to the outside world, but must instead be copied
3099 // via ReflectionFactory.copyMethod.
3100 private Method[] privateGetPublicMethods() {
3101 Method[] res;
3102 ReflectionData<T> rd = reflectionData();
3103 res = rd.publicMethods;
3104 if (res != null) return res;
3105
3106 // No cached value available; compute value recursively.
3107 // Start by fetching public declared methods...
3108 PublicMethods pms = new PublicMethods();
3109 for (Method m : privateGetDeclaredMethods(/* publicOnly */ true)) {
3110 pms.merge(m);
3111 }
3112 // ...then recur over superclass methods...
3113 Class<?> sc = getSuperclass();
3114 if (sc != null) {
3115 for (Method m : sc.privateGetPublicMethods()) {
3116 pms.merge(m);
3117 }
3118 }
3119 // ...and finally over direct superinterfaces.
3120 for (Class<?> intf : getInterfaces(/* cloneArray */ false)) {
3121 for (Method m : intf.privateGetPublicMethods()) {
3122 // static interface methods are not inherited
3123 if (!Modifier.isStatic(m.getModifiers())) {
3124 pms.merge(m);
3125 }
3126 }
3127 }
3128
3129 res = pms.toArray();
3130 rd.publicMethods = res;
3131 return res;
3132 }
3133
3134
3135 //
3136 // Helpers for fetchers of one field, method, or constructor
3137 //
3138
3139 // This method does not copy the returned Field object!
3140 private static Field searchFields(Field[] fields, String name) {
3141 for (Field field : fields) {
3142 if (field.getName().equals(name)) {
3143 return field;
3144 }
3145 }
3146 return null;
3147 }
3148
3149 // Returns a "root" Field object. This Field object must NOT
3150 // be propagated to the outside world, but must instead be copied
3151 // via ReflectionFactory.copyField.
3152 private Field getField0(String name) {
3153 // Note: the intent is that the search algorithm this routine
3154 // uses be equivalent to the ordering imposed by
3155 // privateGetPublicFields(). It fetches only the declared
3156 // public fields for each class, however, to reduce the number
3157 // of Field objects which have to be created for the common
3158 // case where the field being requested is declared in the
3159 // class which is being queried.
3160 Field res;
3161 // Search declared public fields
3162 if ((res = searchFields(privateGetDeclaredFields(true), name)) != null) {
3163 return res;
3164 }
3165 // Direct superinterfaces, recursively
3166 Class<?>[] interfaces = getInterfaces(/* cloneArray */ false);
3167 for (Class<?> c : interfaces) {
3168 if ((res = c.getField0(name)) != null) {
3169 return res;
3170 }
3171 }
3172 // Direct superclass, recursively
3173 if (!isInterface()) {
3174 Class<?> c = getSuperclass();
3175 if (c != null) {
3176 if ((res = c.getField0(name)) != null) {
3177 return res;
3178 }
3179 }
3180 }
3181 return null;
3182 }
3183
3184 // This method does not copy the returned Method object!
3185 private static Method searchMethods(Method[] methods,
3186 String name,
3187 Class<?>[] parameterTypes)
3188 {
3189 ReflectionFactory fact = getReflectionFactory();
3190 Method res = null;
3191 for (Method m : methods) {
3192 if (m.getName().equals(name)
3193 && arrayContentsEq(parameterTypes,
3194 fact.getExecutableSharedParameterTypes(m))
3195 && (res == null
3196 || (res.getReturnType() != m.getReturnType()
3197 && res.getReturnType().isAssignableFrom(m.getReturnType()))))
3198 res = m;
3199 }
3200 return res;
3201 }
3202
3203 private static final Class<?>[] EMPTY_CLASS_ARRAY = new Class<?>[0];
3204
3205 // Returns a "root" Method object. This Method object must NOT
3206 // be propagated to the outside world, but must instead be copied
3207 // via ReflectionFactory.copyMethod.
3208 private Method getMethod0(String name, Class<?>[] parameterTypes) {
3209 PublicMethods.MethodList res = getMethodsRecursive(
3210 name,
3211 parameterTypes == null ? EMPTY_CLASS_ARRAY : parameterTypes,
3212 /* includeStatic */ true, /* publicOnly */ true);
3213 return res == null ? null : res.getMostSpecific();
3214 }
3215
3216 // Returns a list of "root" Method objects. These Method objects must NOT
3217 // be propagated to the outside world, but must instead be copied
3218 // via ReflectionFactory.copyMethod.
3219 private PublicMethods.MethodList getMethodsRecursive(String name,
3220 Class<?>[] parameterTypes,
3221 boolean includeStatic,
3222 boolean publicOnly) {
3223 // 1st check declared methods
3224 Method[] methods = privateGetDeclaredMethods(publicOnly);
3225 PublicMethods.MethodList res = PublicMethods.MethodList
3226 .filter(methods, name, parameterTypes, includeStatic);
3227 // if there is at least one match among declared methods, we need not
3228 // search any further as such match surely overrides matching methods
3229 // declared in superclass(es) or interface(s).
3230 if (res != null) {
3231 return res;
3232 }
3233
3234 // if there was no match among declared methods,
3235 // we must consult the superclass (if any) recursively...
3236 Class<?> sc = getSuperclass();
3237 if (sc != null) {
3238 res = sc.getMethodsRecursive(name, parameterTypes, includeStatic, publicOnly);
3239 }
3240
3241 // ...and coalesce the superclass methods with methods obtained
3242 // from directly implemented interfaces excluding static methods...
3243 for (Class<?> intf : getInterfaces(/* cloneArray */ false)) {
3244 res = PublicMethods.MethodList.merge(
3245 res, intf.getMethodsRecursive(name, parameterTypes, /* includeStatic */ false, publicOnly));
3246 }
3247
3248 return res;
3249 }
3250
3251 // Returns a "root" Constructor object. This Constructor object must NOT
3252 // be propagated to the outside world, but must instead be copied
3253 // via ReflectionFactory.copyConstructor.
3254 private Constructor<T> getConstructor0(Class<?>[] parameterTypes,
3255 int which) throws NoSuchMethodException
3256 {
3257 ReflectionFactory fact = getReflectionFactory();
3258 Constructor<T>[] constructors = privateGetDeclaredConstructors((which == Member.PUBLIC));
3259 for (Constructor<T> constructor : constructors) {
3260 if (arrayContentsEq(parameterTypes,
3261 fact.getExecutableSharedParameterTypes(constructor))) {
3262 return constructor;
3263 }
3264 }
3265 throw new NoSuchMethodException(methodToString("<init>", parameterTypes));
3266 }
3267
3268 //
3269 // Other helpers and base implementation
3270 //
3271
3272 private static boolean arrayContentsEq(Object[] a1, Object[] a2) {
3273 if (a1 == null) {
3274 return a2 == null || a2.length == 0;
3275 }
3276
3277 if (a2 == null) {
3278 return a1.length == 0;
3279 }
3280
3281 if (a1.length != a2.length) {
3282 return false;
3283 }
3284
3285 for (int i = 0; i < a1.length; i++) {
3286 if (a1[i] != a2[i]) {
3287 return false;
3288 }
3289 }
3290
3291 return true;
3292 }
3293
3294 private static Field[] copyFields(Field[] arg) {
3295 Field[] out = new Field[arg.length];
3296 ReflectionFactory fact = getReflectionFactory();
3297 for (int i = 0; i < arg.length; i++) {
3298 out[i] = fact.copyField(arg[i]);
3299 }
3300 return out;
3301 }
3302
3303 private static Method[] copyMethods(Method[] arg) {
3304 Method[] out = new Method[arg.length];
3305 ReflectionFactory fact = getReflectionFactory();
3306 for (int i = 0; i < arg.length; i++) {
3307 out[i] = fact.copyMethod(arg[i]);
3308 }
3309 return out;
3310 }
3311
3312 private static <U> Constructor<U>[] copyConstructors(Constructor<U>[] arg) {
3313 Constructor<U>[] out = arg.clone();
3314 ReflectionFactory fact = getReflectionFactory();
3315 for (int i = 0; i < out.length; i++) {
3316 out[i] = fact.copyConstructor(out[i]);
3317 }
3318 return out;
3319 }
3320
3321 private native Field[] getDeclaredFields0(boolean publicOnly);
3322 private native Method[] getDeclaredMethods0(boolean publicOnly);
3323 private native Constructor<T>[] getDeclaredConstructors0(boolean publicOnly);
3324 private native Class<?>[] getDeclaredClasses0();
3325
3326 /*
3327 * Returns an array containing the components of the Record attribute,
3328 * or null if the attribute is not present.
3329 *
3330 * Note that this method returns non-null array on a class with
3331 * the Record attribute even if this class is not a record.
3332 */
3333 private native RecordComponent[] getRecordComponents0();
3334 private native boolean isRecord0();
3335
3336 /**
3337 * Helper method to get the method name from arguments.
3338 */
3339 private String methodToString(String name, Class<?>[] argTypes) {
3340 return getName() + '.' + name +
3341 ((argTypes == null || argTypes.length == 0) ?
3342 "()" :
3343 Arrays.stream(argTypes)
3344 .map(c -> c == null ? "null" : c.getName())
3345 .collect(Collectors.joining(",", "(", ")")));
3346 }
3347
3348 /** use serialVersionUID from JDK 1.1 for interoperability */
3349 @java.io.Serial
3350 private static final long serialVersionUID = 3206093459760846163L;
3351
3352
3353 /**
3354 * Class Class is special cased within the Serialization Stream Protocol.
3355 *
3356 * A Class instance is written initially into an ObjectOutputStream in the
3357 * following format:
3358 * <pre>
3359 * {@code TC_CLASS} ClassDescriptor
3360 * A ClassDescriptor is a special cased serialization of
3361 * a {@code java.io.ObjectStreamClass} instance.
3362 * </pre>
3363 * A new handle is generated for the initial time the class descriptor
3364 * is written into the stream. Future references to the class descriptor
3365 * are written as references to the initial class descriptor instance.
3366 *
3367 * @see java.io.ObjectStreamClass
3368 */
3369 @java.io.Serial
3370 private static final ObjectStreamField[] serialPersistentFields =
3371 new ObjectStreamField[0];
3372
3373
3374 /**
3375 * Returns the assertion status that would be assigned to this
3376 * class if it were to be initialized at the time this method is invoked.
3377 * If this class has had its assertion status set, the most recent
3378 * setting will be returned; otherwise, if any package default assertion
3379 * status pertains to this class, the most recent setting for the most
3380 * specific pertinent package default assertion status is returned;
3381 * otherwise, if this class is not a system class (i.e., it has a
3382 * class loader) its class loader's default assertion status is returned;
3383 * otherwise, the system class default assertion status is returned.
3384 *
3385 * @apiNote
3386 * Few programmers will have any need for this method; it is provided
3387 * for the benefit of the JDK itself. (It allows a class to determine at
3388 * the time that it is initialized whether assertions should be enabled.)
3389 * Note that this method is not guaranteed to return the actual
3390 * assertion status that was (or will be) associated with the specified
3391 * class when it was (or will be) initialized.
3392 *
3393 * @return the desired assertion status of the specified class.
3394 * @see java.lang.ClassLoader#setClassAssertionStatus
3395 * @see java.lang.ClassLoader#setPackageAssertionStatus
3396 * @see java.lang.ClassLoader#setDefaultAssertionStatus
3397 * @since 1.4
3398 */
3399 public boolean desiredAssertionStatus() {
3400 ClassLoader loader = classLoader;
3401 // If the loader is null this is a system class, so ask the VM
3402 if (loader == null)
3403 return desiredAssertionStatus0(this);
3404
3405 // If the classloader has been initialized with the assertion
3406 // directives, ask it. Otherwise, ask the VM.
3407 synchronized(loader.assertionLock) {
3408 if (loader.classAssertionStatus != null) {
3409 return loader.desiredAssertionStatus(getName());
3410 }
3411 }
3412 return desiredAssertionStatus0(this);
3413 }
3414
3415 // Retrieves the desired assertion status of this class from the VM
3416 private static native boolean desiredAssertionStatus0(Class<?> clazz);
3417
3418 /**
3419 * Returns true if and only if this class was declared as an enum in the
3420 * source code.
3421 *
3422 * Note that {@link java.lang.Enum} is not itself an enum class.
3423 *
3424 * Also note that if an enum constant is declared with a class body,
3425 * the class of that enum constant object is an anonymous class
3426 * and <em>not</em> the class of the declaring enum class. The
3427 * {@link Enum#getDeclaringClass} method of an enum constant can
3428 * be used to get the class of the enum class declaring the
3429 * constant.
3430 *
3431 * @return true if and only if this class was declared as an enum in the
3432 * source code
3433 * @since 1.5
3434 * @jls 8.9.1 Enum Constants
3435 */
3436 public boolean isEnum() {
3437 // An enum must both directly extend java.lang.Enum and have
3438 // the ENUM bit set; classes for specialized enum constants
3439 // don't do the former.
3440 return (this.getModifiers() & ENUM) != 0 &&
3441 this.getSuperclass() == java.lang.Enum.class;
3442 }
3443
3444 /**
3445 * Returns {@code true} if and only if this class is a record class.
3446 *
3447 * <p> The {@linkplain #getSuperclass() direct superclass} of a record
3448 * class is {@code java.lang.Record}. A record class is {@linkplain
3449 * Modifier#FINAL final}. A record class has (possibly zero) record
3450 * components; {@link #getRecordComponents()} returns a non-null but
3451 * possibly empty value for a record.
3452 *
3453 * <p> Note that class {@link Record} is not a record class and thus
3454 * invoking this method on class {@code Record} returns {@code false}.
3455 *
3456 * @return true if and only if this class is a record class, otherwise false
3457 * @jls 8.10 Record Classes
3458 * @since 16
3459 */
3460 public boolean isRecord() {
3461 // this superclass and final modifier check is not strictly necessary
3462 // they are intrinsified and serve as a fast-path check
3463 return getSuperclass() == java.lang.Record.class &&
3464 (this.getModifiers() & Modifier.FINAL) != 0 &&
3465 isRecord0();
3466 }
3467
3468 // Fetches the factory for reflective objects
3469 private static ReflectionFactory getReflectionFactory() {
3470 var factory = reflectionFactory;
3471 if (factory != null) {
3472 return factory;
3473 }
3474 return reflectionFactory = ReflectionFactory.getReflectionFactory();
3475 }
3476 private static ReflectionFactory reflectionFactory;
3477
3478 /**
3479 * When CDS is enabled, the Class class may be aot-initialized. However,
3480 * we can't archive reflectionFactory, so we reset it to null, so it
3481 * will be allocated again at runtime.
3482 */
3483 private static void resetArchivedStates() {
3484 reflectionFactory = null;
3485 }
3486
3487 /**
3488 * Returns the elements of this enum class or null if this
3489 * Class object does not represent an enum class.
3490 *
3491 * @return an array containing the values comprising the enum class
3492 * represented by this {@code Class} object in the order they're
3493 * declared, or null if this {@code Class} object does not
3494 * represent an enum class
3495 * @since 1.5
3496 * @jls 8.9.1 Enum Constants
3497 */
3498 public T[] getEnumConstants() {
3499 T[] values = getEnumConstantsShared();
3500 return (values != null) ? values.clone() : null;
3501 }
3502
3503 /**
3504 * Returns the elements of this enum class or null if this
3505 * Class object does not represent an enum class;
3506 * identical to getEnumConstants except that the result is
3507 * uncloned, cached, and shared by all callers.
3508 */
3509 T[] getEnumConstantsShared() {
3510 T[] constants = enumConstants;
3511 if (constants == null) {
3512 if (!isEnum()) return null;
3513 try {
3514 final Method values = getMethod("values");
3515 values.setAccessible(true);
3516 @SuppressWarnings("unchecked")
3517 T[] temporaryConstants = (T[])values.invoke(null);
3518 enumConstants = constants = temporaryConstants;
3519 }
3520 // These can happen when users concoct enum-like classes
3521 // that don't comply with the enum spec.
3522 catch (InvocationTargetException | NoSuchMethodException |
3523 IllegalAccessException | NullPointerException |
3524 ClassCastException ex) { return null; }
3525 }
3526 return constants;
3527 }
3528 private transient volatile T[] enumConstants;
3529
3530 /**
3531 * Returns a map from simple name to enum constant. This package-private
3532 * method is used internally by Enum to implement
3533 * {@code public static <T extends Enum<T>> T valueOf(Class<T>, String)}
3534 * efficiently. Note that the map is returned by this method is
3535 * created lazily on first use. Typically it won't ever get created.
3536 */
3537 Map<String, T> enumConstantDirectory() {
3538 Map<String, T> directory = enumConstantDirectory;
3539 if (directory == null) {
3540 T[] universe = getEnumConstantsShared();
3541 if (universe == null)
3542 throw new IllegalArgumentException(
3543 getName() + " is not an enum class");
3544 directory = HashMap.newHashMap(universe.length);
3545 for (T constant : universe) {
3546 directory.put(((Enum<?>)constant).name(), constant);
3547 }
3548 enumConstantDirectory = directory;
3549 }
3550 return directory;
3551 }
3552 private transient volatile Map<String, T> enumConstantDirectory;
3553
3554 /**
3555 * Casts an object to the class or interface represented
3556 * by this {@code Class} object.
3557 *
3558 * @param obj the object to be cast
3559 * @return the object after casting, or null if obj is null
3560 *
3561 * @throws ClassCastException if the object is not
3562 * null and is not assignable to the type T.
3563 *
3564 * @since 1.5
3565 */
3566 @SuppressWarnings("unchecked")
3567 @IntrinsicCandidate
3568 public T cast(Object obj) {
3569 if (obj != null && !isInstance(obj))
3570 throw new ClassCastException(cannotCastMsg(obj));
3571 return (T) obj;
3572 }
3573
3574 private String cannotCastMsg(Object obj) {
3575 return "Cannot cast " + obj.getClass().getName() + " to " + getName();
3576 }
3577
3578 /**
3579 * Casts this {@code Class} object to represent a subclass of the class
3580 * represented by the specified class object. Checks that the cast
3581 * is valid, and throws a {@code ClassCastException} if it is not. If
3582 * this method succeeds, it always returns a reference to this {@code Class} object.
3583 *
3584 * <p>This method is useful when a client needs to "narrow" the type of
3585 * a {@code Class} object to pass it to an API that restricts the
3586 * {@code Class} objects that it is willing to accept. A cast would
3587 * generate a compile-time warning, as the correctness of the cast
3588 * could not be checked at runtime (because generic types are implemented
3589 * by erasure).
3590 *
3591 * @param <U> the type to cast this {@code Class} object to
3592 * @param clazz the class of the type to cast this {@code Class} object to
3593 * @return this {@code Class} object, cast to represent a subclass of
3594 * the specified class object.
3595 * @throws ClassCastException if this {@code Class} object does not
3596 * represent a subclass of the specified class (here "subclass" includes
3597 * the class itself).
3598 * @since 1.5
3599 */
3600 @SuppressWarnings("unchecked")
3601 public <U> Class<? extends U> asSubclass(Class<U> clazz) {
3602 if (clazz.isAssignableFrom(this))
3603 return (Class<? extends U>) this;
3604 else
3605 throw new ClassCastException(this.toString());
3606 }
3607
3608 /**
3609 * {@inheritDoc}
3610 * <p>Note that any annotation returned by this method is a
3611 * declaration annotation.
3612 *
3613 * @throws NullPointerException {@inheritDoc}
3614 * @since 1.5
3615 */
3616 @Override
3617 @SuppressWarnings("unchecked")
3618 public <A extends Annotation> A getAnnotation(Class<A> annotationClass) {
3619 Objects.requireNonNull(annotationClass);
3620
3621 return (A) annotationData().annotations.get(annotationClass);
3622 }
3623
3624 /**
3625 * {@inheritDoc}
3626 * @throws NullPointerException {@inheritDoc}
3627 * @since 1.5
3628 */
3629 @Override
3630 public boolean isAnnotationPresent(Class<? extends Annotation> annotationClass) {
3631 return GenericDeclaration.super.isAnnotationPresent(annotationClass);
3632 }
3633
3634 /**
3635 * {@inheritDoc}
3636 * <p>Note that any annotations returned by this method are
3637 * declaration annotations.
3638 *
3639 * @throws NullPointerException {@inheritDoc}
3640 * @since 1.8
3641 */
3642 @Override
3643 public <A extends Annotation> A[] getAnnotationsByType(Class<A> annotationClass) {
3644 Objects.requireNonNull(annotationClass);
3645
3646 AnnotationData annotationData = annotationData();
3647 return AnnotationSupport.getAssociatedAnnotations(annotationData.declaredAnnotations,
3648 this,
3649 annotationClass);
3650 }
3651
3652 /**
3653 * {@inheritDoc}
3654 * <p>Note that any annotations returned by this method are
3655 * declaration annotations.
3656 *
3657 * @since 1.5
3658 */
3659 @Override
3660 public Annotation[] getAnnotations() {
3661 return AnnotationParser.toArray(annotationData().annotations);
3662 }
3663
3664 /**
3665 * {@inheritDoc}
3666 * <p>Note that any annotation returned by this method is a
3667 * declaration annotation.
3668 *
3669 * @throws NullPointerException {@inheritDoc}
3670 * @since 1.8
3671 */
3672 @Override
3673 @SuppressWarnings("unchecked")
3674 public <A extends Annotation> A getDeclaredAnnotation(Class<A> annotationClass) {
3675 Objects.requireNonNull(annotationClass);
3676
3677 return (A) annotationData().declaredAnnotations.get(annotationClass);
3678 }
3679
3680 /**
3681 * {@inheritDoc}
3682 * <p>Note that any annotations returned by this method are
3683 * declaration annotations.
3684 *
3685 * @throws NullPointerException {@inheritDoc}
3686 * @since 1.8
3687 */
3688 @Override
3689 public <A extends Annotation> A[] getDeclaredAnnotationsByType(Class<A> annotationClass) {
3690 Objects.requireNonNull(annotationClass);
3691
3692 return AnnotationSupport.getDirectlyAndIndirectlyPresent(annotationData().declaredAnnotations,
3693 annotationClass);
3694 }
3695
3696 /**
3697 * {@inheritDoc}
3698 * <p>Note that any annotations returned by this method are
3699 * declaration annotations.
3700 *
3701 * @since 1.5
3702 */
3703 @Override
3704 public Annotation[] getDeclaredAnnotations() {
3705 return AnnotationParser.toArray(annotationData().declaredAnnotations);
3706 }
3707
3708 // annotation data that might get invalidated when JVM TI RedefineClasses() is called
3709 private static class AnnotationData {
3710 final Map<Class<? extends Annotation>, Annotation> annotations;
3711 final Map<Class<? extends Annotation>, Annotation> declaredAnnotations;
3712
3713 // Value of classRedefinedCount when we created this AnnotationData instance
3714 final int redefinedCount;
3715
3716 AnnotationData(Map<Class<? extends Annotation>, Annotation> annotations,
3717 Map<Class<? extends Annotation>, Annotation> declaredAnnotations,
3718 int redefinedCount) {
3719 this.annotations = annotations;
3720 this.declaredAnnotations = declaredAnnotations;
3721 this.redefinedCount = redefinedCount;
3722 }
3723 }
3724
3725 // Annotations cache
3726 @SuppressWarnings("UnusedDeclaration")
3727 private transient volatile AnnotationData annotationData;
3728
3729 private AnnotationData annotationData() {
3730 while (true) { // retry loop
3731 AnnotationData annotationData = this.annotationData;
3732 int classRedefinedCount = this.classRedefinedCount;
3733 if (annotationData != null &&
3734 annotationData.redefinedCount == classRedefinedCount) {
3735 return annotationData;
3736 }
3737 // null or stale annotationData -> optimistically create new instance
3738 AnnotationData newAnnotationData = createAnnotationData(classRedefinedCount);
3739 // try to install it
3740 if (Atomic.casAnnotationData(this, annotationData, newAnnotationData)) {
3741 // successfully installed new AnnotationData
3742 return newAnnotationData;
3743 }
3744 }
3745 }
3746
3747 private AnnotationData createAnnotationData(int classRedefinedCount) {
3748 Map<Class<? extends Annotation>, Annotation> declaredAnnotations =
3749 AnnotationParser.parseAnnotations(getRawAnnotations(), getConstantPool(), this);
3750 Class<?> superClass = getSuperclass();
3751 Map<Class<? extends Annotation>, Annotation> annotations = null;
3752 if (superClass != null) {
3753 Map<Class<? extends Annotation>, Annotation> superAnnotations =
3754 superClass.annotationData().annotations;
3755 for (Map.Entry<Class<? extends Annotation>, Annotation> e : superAnnotations.entrySet()) {
3756 Class<? extends Annotation> annotationClass = e.getKey();
3757 if (AnnotationType.getInstance(annotationClass).isInherited()) {
3758 if (annotations == null) { // lazy construction
3759 annotations = LinkedHashMap.newLinkedHashMap(Math.max(
3760 declaredAnnotations.size(),
3761 Math.min(12, declaredAnnotations.size() + superAnnotations.size())
3762 )
3763 );
3764 }
3765 annotations.put(annotationClass, e.getValue());
3766 }
3767 }
3768 }
3769 if (annotations == null) {
3770 // no inherited annotations -> share the Map with declaredAnnotations
3771 annotations = declaredAnnotations;
3772 } else {
3773 // at least one inherited annotation -> declared may override inherited
3774 annotations.putAll(declaredAnnotations);
3775 }
3776 return new AnnotationData(annotations, declaredAnnotations, classRedefinedCount);
3777 }
3778
3779 // Annotation interfaces cache their internal (AnnotationType) form
3780
3781 @SuppressWarnings("UnusedDeclaration")
3782 private transient volatile AnnotationType annotationType;
3783
3784 boolean casAnnotationType(AnnotationType oldType, AnnotationType newType) {
3785 return Atomic.casAnnotationType(this, oldType, newType);
3786 }
3787
3788 AnnotationType getAnnotationType() {
3789 return annotationType;
3790 }
3791
3792 Map<Class<? extends Annotation>, Annotation> getDeclaredAnnotationMap() {
3793 return annotationData().declaredAnnotations;
3794 }
3795
3796 /* Backing store of user-defined values pertaining to this class.
3797 * Maintained by the ClassValue class.
3798 */
3799 transient ClassValue.ClassValueMap classValueMap;
3800
3801 /**
3802 * Returns an {@code AnnotatedType} object that represents the use of a
3803 * type to specify the superclass of the entity represented by this {@code
3804 * Class} object. (The <em>use</em> of type Foo to specify the superclass
3805 * in '... extends Foo' is distinct from the <em>declaration</em> of class
3806 * Foo.)
3807 *
3808 * <p> If this {@code Class} object represents a class whose declaration
3809 * does not explicitly indicate an annotated superclass, then the return
3810 * value is an {@code AnnotatedType} object representing an element with no
3811 * annotations.
3812 *
3813 * <p> If this {@code Class} represents either the {@code Object} class, an
3814 * interface type, an array type, a primitive type, or void, the return
3815 * value is {@code null}.
3816 *
3817 * @return an object representing the superclass
3818 * @since 1.8
3819 */
3820 public AnnotatedType getAnnotatedSuperclass() {
3821 if (this == Object.class ||
3822 isInterface() ||
3823 isArray() ||
3824 isPrimitive() ||
3825 this == Void.TYPE) {
3826 return null;
3827 }
3828
3829 return TypeAnnotationParser.buildAnnotatedSuperclass(getRawTypeAnnotations(), getConstantPool(), this);
3830 }
3831
3832 /**
3833 * Returns an array of {@code AnnotatedType} objects that represent the use
3834 * of types to specify superinterfaces of the entity represented by this
3835 * {@code Class} object. (The <em>use</em> of type Foo to specify a
3836 * superinterface in '... implements Foo' is distinct from the
3837 * <em>declaration</em> of interface Foo.)
3838 *
3839 * <p> If this {@code Class} object represents a class, the return value is
3840 * an array containing objects representing the uses of interface types to
3841 * specify interfaces implemented by the class. The order of the objects in
3842 * the array corresponds to the order of the interface types used in the
3843 * 'implements' clause of the declaration of this {@code Class} object.
3844 *
3845 * <p> If this {@code Class} object represents an interface, the return
3846 * value is an array containing objects representing the uses of interface
3847 * types to specify interfaces directly extended by the interface. The
3848 * order of the objects in the array corresponds to the order of the
3849 * interface types used in the 'extends' clause of the declaration of this
3850 * {@code Class} object.
3851 *
3852 * <p> If this {@code Class} object represents a class or interface whose
3853 * declaration does not explicitly indicate any annotated superinterfaces,
3854 * the return value is an array of length 0.
3855 *
3856 * <p> If this {@code Class} object represents either the {@code Object}
3857 * class, an array type, a primitive type, or void, the return value is an
3858 * array of length 0.
3859 *
3860 * @return an array representing the superinterfaces
3861 * @since 1.8
3862 */
3863 public AnnotatedType[] getAnnotatedInterfaces() {
3864 return TypeAnnotationParser.buildAnnotatedInterfaces(getRawTypeAnnotations(), getConstantPool(), this);
3865 }
3866
3867 private native Class<?> getNestHost0();
3868
3869 /**
3870 * Returns the nest host of the <a href=#nest>nest</a> to which the class
3871 * or interface represented by this {@code Class} object belongs.
3872 * Every class and interface belongs to exactly one nest.
3873 *
3874 * If the nest host of this class or interface has previously
3875 * been determined, then this method returns the nest host.
3876 * If the nest host of this class or interface has
3877 * not previously been determined, then this method determines the nest
3878 * host using the algorithm of JVMS 5.4.4, and returns it.
3879 *
3880 * Often, a class or interface belongs to a nest consisting only of itself,
3881 * in which case this method returns {@code this} to indicate that the class
3882 * or interface is the nest host.
3883 *
3884 * <p>If this {@code Class} object represents a primitive type, an array type,
3885 * or {@code void}, then this method returns {@code this},
3886 * indicating that the represented entity belongs to the nest consisting only of
3887 * itself, and is the nest host.
3888 *
3889 * @return the nest host of this class or interface
3890 *
3891 * @since 11
3892 * @jvms 4.7.28 The {@code NestHost} Attribute
3893 * @jvms 4.7.29 The {@code NestMembers} Attribute
3894 * @jvms 5.4.4 Access Control
3895 */
3896 public Class<?> getNestHost() {
3897 if (isPrimitive() || isArray()) {
3898 return this;
3899 }
3900 return getNestHost0();
3901 }
3902
3903 /**
3904 * Determines if the given {@code Class} is a nestmate of the
3905 * class or interface represented by this {@code Class} object.
3906 * Two classes or interfaces are nestmates
3907 * if they have the same {@linkplain #getNestHost() nest host}.
3908 *
3909 * @param c the class to check
3910 * @return {@code true} if this class and {@code c} are members of
3911 * the same nest; and {@code false} otherwise.
3912 *
3913 * @since 11
3914 */
3915 public boolean isNestmateOf(Class<?> c) {
3916 if (this == c) {
3917 return true;
3918 }
3919 if (isPrimitive() || isArray() ||
3920 c.isPrimitive() || c.isArray()) {
3921 return false;
3922 }
3923
3924 return getNestHost() == c.getNestHost();
3925 }
3926
3927 private native Class<?>[] getNestMembers0();
3928
3929 /**
3930 * Returns an array containing {@code Class} objects representing all the
3931 * classes and interfaces that are members of the nest to which the class
3932 * or interface represented by this {@code Class} object belongs.
3933 *
3934 * First, this method obtains the {@linkplain #getNestHost() nest host},
3935 * {@code H}, of the nest to which the class or interface represented by
3936 * this {@code Class} object belongs. The zeroth element of the returned
3937 * array is {@code H}.
3938 *
3939 * Then, for each class or interface {@code C} which is recorded by {@code H}
3940 * as being a member of its nest, this method attempts to obtain the {@code Class}
3941 * object for {@code C} (using {@linkplain #getClassLoader() the defining class
3942 * loader} of the current {@code Class} object), and then obtains the
3943 * {@linkplain #getNestHost() nest host} of the nest to which {@code C} belongs.
3944 * The classes and interfaces which are recorded by {@code H} as being members
3945 * of its nest, and for which {@code H} can be determined as their nest host,
3946 * are indicated by subsequent elements of the returned array. The order of
3947 * such elements is unspecified. Duplicates are permitted.
3948 *
3949 * <p>If this {@code Class} object represents a primitive type, an array type,
3950 * or {@code void}, then this method returns a single-element array containing
3951 * {@code this}.
3952 *
3953 * @apiNote
3954 * The returned array includes only the nest members recorded in the {@code NestMembers}
3955 * attribute, and not any hidden classes that were added to the nest via
3956 * {@link MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
3957 * Lookup::defineHiddenClass}.
3958 *
3959 * @return an array of all classes and interfaces in the same nest as
3960 * this class or interface
3961 *
3962 * @since 11
3963 * @see #getNestHost()
3964 * @jvms 4.7.28 The {@code NestHost} Attribute
3965 * @jvms 4.7.29 The {@code NestMembers} Attribute
3966 */
3967 public Class<?>[] getNestMembers() {
3968 if (isPrimitive() || isArray()) {
3969 return new Class<?>[] { this };
3970 }
3971 Class<?>[] members = getNestMembers0();
3972 // Can't actually enable this due to bootstrapping issues
3973 // assert(members.length != 1 || members[0] == this); // expected invariant from VM
3974 return members;
3975 }
3976
3977 /**
3978 * Returns the descriptor string of the entity (class, interface, array class,
3979 * primitive type, or {@code void}) represented by this {@code Class} object.
3980 *
3981 * <p> If this {@code Class} object represents a class or interface,
3982 * not an array class, then:
3983 * <ul>
3984 * <li> If the class or interface is not {@linkplain Class#isHidden() hidden},
3985 * then the result is a field descriptor (JVMS {@jvms 4.3.2})
3986 * for the class or interface. Calling
3987 * {@link ClassDesc#ofDescriptor(String) ClassDesc::ofDescriptor}
3988 * with the result descriptor string produces a {@link ClassDesc ClassDesc}
3989 * describing this class or interface.
3990 * <li> If the class or interface is {@linkplain Class#isHidden() hidden},
3991 * then the result is a string of the form:
3992 * <blockquote>
3993 * {@code "L" +} <em>N</em> {@code + "." + <suffix> + ";"}
3994 * </blockquote>
3995 * where <em>N</em> is the {@linkplain ClassLoader##binary-name binary name}
3996 * encoded in internal form indicated by the {@code class} file passed to
3997 * {@link MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
3998 * Lookup::defineHiddenClass}, and {@code <suffix>} is an unqualified name.
3999 * A hidden class or interface has no {@linkplain ClassDesc nominal descriptor}.
4000 * The result string is not a type descriptor.
4001 * </ul>
4002 *
4003 * <p> If this {@code Class} object represents an array class, then
4004 * the result is a string consisting of one or more '{@code [}' characters
4005 * representing the depth of the array nesting, followed by the
4006 * descriptor string of the element type.
4007 * <ul>
4008 * <li> If the element type is not a {@linkplain Class#isHidden() hidden} class
4009 * or interface, then this array class can be described nominally.
4010 * Calling {@link ClassDesc#ofDescriptor(String) ClassDesc::ofDescriptor}
4011 * with the result descriptor string produces a {@link ClassDesc ClassDesc}
4012 * describing this array class.
4013 * <li> If the element type is a {@linkplain Class#isHidden() hidden} class or
4014 * interface, then this array class cannot be described nominally.
4015 * The result string is not a type descriptor.
4016 * </ul>
4017 *
4018 * <p> If this {@code Class} object represents a primitive type or
4019 * {@code void}, then the result is a field descriptor string which
4020 * is a one-letter code corresponding to a primitive type or {@code void}
4021 * ({@code "B", "C", "D", "F", "I", "J", "S", "Z", "V"}) (JVMS {@jvms 4.3.2}).
4022 *
4023 * @return the descriptor string for this {@code Class} object
4024 * @jvms 4.3.2 Field Descriptors
4025 * @since 12
4026 */
4027 @Override
4028 public String descriptorString() {
4029 if (isPrimitive())
4030 return Wrapper.forPrimitiveType(this).basicTypeString();
4031
4032 if (isArray()) {
4033 return "[".concat(componentType.descriptorString());
4034 } else if (isHidden()) {
4035 String name = getName();
4036 int index = name.indexOf('/');
4037 return new StringBuilder(name.length() + 2)
4038 .append('L')
4039 .append(name.substring(0, index).replace('.', '/'))
4040 .append('.')
4041 .append(name, index + 1, name.length())
4042 .append(';')
4043 .toString();
4044 } else {
4045 String name = getName().replace('.', '/');
4046 return StringConcatHelper.concat("L", name, ";");
4047 }
4048 }
4049
4050 /**
4051 * Returns the component type of this {@code Class}, if it describes
4052 * an array type, or {@code null} otherwise.
4053 *
4054 * @implSpec
4055 * Equivalent to {@link Class#getComponentType()}.
4056 *
4057 * @return a {@code Class} describing the component type, or {@code null}
4058 * if this {@code Class} does not describe an array type
4059 * @since 12
4060 */
4061 @Override
4062 public Class<?> componentType() {
4063 return getComponentType();
4064 }
4065
4066 /**
4067 * Returns a {@code Class} for an array type whose component type
4068 * is described by this {@linkplain Class}.
4069 *
4070 * @throws UnsupportedOperationException if this component type is {@linkplain
4071 * Void#TYPE void} or if the number of dimensions of the resulting array
4072 * type would exceed 255.
4073 * @return a {@code Class} describing the array type
4074 * @jvms 4.3.2 Field Descriptors
4075 * @jvms 4.4.1 The {@code CONSTANT_Class_info} Structure
4076 * @since 12
4077 */
4078 @Override
4079 public Class<?> arrayType() {
4080 try {
4081 return Array.newInstance(this, 0).getClass();
4082 } catch (IllegalArgumentException iae) {
4083 throw new UnsupportedOperationException(iae);
4084 }
4085 }
4086
4087 /**
4088 * Returns a nominal descriptor for this instance, if one can be
4089 * constructed, or an empty {@link Optional} if one cannot be.
4090 *
4091 * @return An {@link Optional} containing the resulting nominal descriptor,
4092 * or an empty {@link Optional} if one cannot be constructed.
4093 * @since 12
4094 */
4095 @Override
4096 public Optional<ClassDesc> describeConstable() {
4097 Class<?> c = isArray() ? elementType() : this;
4098 return c.isHidden() ? Optional.empty()
4099 : Optional.of(ConstantUtils.classDesc(this));
4100 }
4101
4102 /**
4103 * Returns {@code true} if and only if the underlying class is a hidden class.
4104 *
4105 * @return {@code true} if and only if this class is a hidden class.
4106 *
4107 * @since 15
4108 * @see MethodHandles.Lookup#defineHiddenClass
4109 * @see Class##hiddenClasses Hidden Classes
4110 */
4111 @IntrinsicCandidate
4112 public native boolean isHidden();
4113
4114 /**
4115 * Returns an array containing {@code Class} objects representing the
4116 * direct subinterfaces or subclasses permitted to extend or
4117 * implement this class or interface if it is sealed. The order of such elements
4118 * is unspecified. The array is empty if this sealed class or interface has no
4119 * permitted subclass. If this {@code Class} object represents a primitive type,
4120 * {@code void}, an array type, or a class or interface that is not sealed,
4121 * that is {@link #isSealed()} returns {@code false}, then this method returns {@code null}.
4122 * Conversely, if {@link #isSealed()} returns {@code true}, then this method
4123 * returns a non-null value.
4124 *
4125 * For each class or interface {@code C} which is recorded as a permitted
4126 * direct subinterface or subclass of this class or interface,
4127 * this method attempts to obtain the {@code Class}
4128 * object for {@code C} (using {@linkplain #getClassLoader() the defining class
4129 * loader} of the current {@code Class} object).
4130 * The {@code Class} objects which can be obtained and which are direct
4131 * subinterfaces or subclasses of this class or interface,
4132 * are indicated by elements of the returned array. If a {@code Class} object
4133 * cannot be obtained, it is silently ignored, and not included in the result
4134 * array.
4135 *
4136 * @return an array of {@code Class} objects of the permitted subclasses of this class
4137 * or interface, or {@code null} if this class or interface is not sealed.
4138 *
4139 * @jls 8.1 Class Declarations
4140 * @jls 9.1 Interface Declarations
4141 * @since 17
4142 */
4143 public Class<?>[] getPermittedSubclasses() {
4144 Class<?>[] subClasses;
4145 if (isArray() || isPrimitive() || (subClasses = getPermittedSubclasses0()) == null) {
4146 return null;
4147 }
4148 if (subClasses.length > 0) {
4149 if (Arrays.stream(subClasses).anyMatch(c -> !isDirectSubType(c))) {
4150 subClasses = Arrays.stream(subClasses)
4151 .filter(this::isDirectSubType)
4152 .toArray(s -> new Class<?>[s]);
4153 }
4154 }
4155 return subClasses;
4156 }
4157
4158 private boolean isDirectSubType(Class<?> c) {
4159 if (isInterface()) {
4160 for (Class<?> i : c.getInterfaces(/* cloneArray */ false)) {
4161 if (i == this) {
4162 return true;
4163 }
4164 }
4165 } else {
4166 return c.getSuperclass() == this;
4167 }
4168 return false;
4169 }
4170
4171 /**
4172 * Returns {@code true} if and only if this {@code Class} object represents
4173 * a sealed class or interface. If this {@code Class} object represents a
4174 * primitive type, {@code void}, or an array type, this method returns
4175 * {@code false}. A sealed class or interface has (possibly zero) permitted
4176 * subclasses; {@link #getPermittedSubclasses()} returns a non-null but
4177 * possibly empty value for a sealed class or interface.
4178 *
4179 * @return {@code true} if and only if this {@code Class} object represents
4180 * a sealed class or interface.
4181 *
4182 * @jls 8.1 Class Declarations
4183 * @jls 9.1 Interface Declarations
4184 * @since 17
4185 */
4186 public boolean isSealed() {
4187 if (isArray() || isPrimitive()) {
4188 return false;
4189 }
4190 return getPermittedSubclasses() != null;
4191 }
4192
4193 private native Class<?>[] getPermittedSubclasses0();
4194
4195 /*
4196 * Return the class's major and minor class file version packed into an int.
4197 * The high order 16 bits contain the class's minor version. The low order
4198 * 16 bits contain the class's major version.
4199 *
4200 * If the class is an array type then the class file version of its element
4201 * type is returned. If the class is a primitive type then the latest class
4202 * file major version is returned and zero is returned for the minor version.
4203 */
4204 /* package-private */
4205 int getClassFileVersion() {
4206 Class<?> c = isArray() ? elementType() : this;
4207 return c.getClassFileVersion0();
4208 }
4209
4210 private native int getClassFileVersion0();
4211
4212 /*
4213 * Return the access flags as they were in the class's bytecode, including
4214 * the original setting of ACC_SUPER.
4215 *
4216 * If the class is an array type then the access flags of the element type is
4217 * returned. If the class is a primitive then ACC_ABSTRACT | ACC_FINAL | ACC_PUBLIC.
4218 */
4219 private int getClassAccessFlagsRaw() {
4220 Class<?> c = isArray() ? elementType() : this;
4221 return c.getClassAccessFlagsRaw0();
4222 }
4223
4224 private native int getClassAccessFlagsRaw0();
4225 }