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.Constructor;
42 import java.lang.reflect.Executable;
43 import java.lang.reflect.Field;
44 import java.lang.reflect.GenericArrayType;
45 import java.lang.reflect.GenericDeclaration;
46 import java.lang.reflect.InvocationTargetException;
47 import java.lang.reflect.Member;
48 import java.lang.reflect.Method;
49 import java.lang.reflect.Modifier;
50 import java.lang.reflect.RecordComponent;
51 import java.lang.reflect.Type;
52 import java.lang.reflect.TypeVariable;
53 import java.lang.constant.Constable;
54 import java.net.URL;
55 import java.security.AllPermission;
56 import java.security.Permissions;
57 import java.security.ProtectionDomain;
58 import java.util.ArrayList;
59 import java.util.Arrays;
60 import java.util.Collection;
61 import java.util.HashMap;
62 import java.util.LinkedHashMap;
63 import java.util.LinkedHashSet;
64 import java.util.List;
65 import java.util.Map;
66 import java.util.Objects;
67 import java.util.Optional;
68 import java.util.Set;
69 import java.util.stream.Collectors;
70
71 import jdk.internal.constant.ConstantUtils;
72 import jdk.internal.loader.BootLoader;
73 import jdk.internal.loader.BuiltinClassLoader;
74 import jdk.internal.misc.Unsafe;
75 import jdk.internal.module.Resources;
76 import jdk.internal.reflect.CallerSensitive;
77 import jdk.internal.reflect.CallerSensitiveAdapter;
78 import jdk.internal.reflect.ConstantPool;
79 import jdk.internal.reflect.Reflection;
80 import jdk.internal.reflect.ReflectionFactory;
81 import jdk.internal.vm.annotation.AOTRuntimeSetup;
82 import jdk.internal.vm.annotation.AOTSafeClassInitializer;
83 import jdk.internal.vm.annotation.IntrinsicCandidate;
84 import jdk.internal.vm.annotation.Stable;
85
86 import sun.invoke.util.Wrapper;
87 import sun.reflect.generics.factory.CoreReflectionFactory;
88 import sun.reflect.generics.factory.GenericsFactory;
89 import sun.reflect.generics.repository.ClassRepository;
90 import sun.reflect.generics.repository.MethodRepository;
91 import sun.reflect.generics.repository.ConstructorRepository;
92 import sun.reflect.generics.scope.ClassScope;
93 import sun.reflect.annotation.*;
94
95 /**
96 * Instances of the class {@code Class} represent classes and
97 * interfaces in a running Java application. An enum class and a record
98 * class are kinds of class; an annotation interface is a kind of
99 * interface. Every array also belongs to a class that is reflected as
100 * a {@code Class} object that is shared by all arrays with the same
101 * element type and number of dimensions. The primitive Java types
102 * ({@code boolean}, {@code byte}, {@code char}, {@code short}, {@code
103 * int}, {@code long}, {@code float}, and {@code double}), and the
104 * keyword {@code void} are also represented as {@code Class} objects.
105 *
106 * <p> {@code Class} has no public constructor. Instead a {@code Class}
107 * object is constructed automatically by the Java Virtual Machine when
108 * a class is derived from the bytes of a {@code class} file through
109 * the invocation of one of the following methods:
110 * <ul>
111 * <li> {@link ClassLoader#defineClass(String, byte[], int, int) ClassLoader::defineClass}
112 * <li> {@link java.lang.invoke.MethodHandles.Lookup#defineClass(byte[])
113 * java.lang.invoke.MethodHandles.Lookup::defineClass}
114 * <li> {@link java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
115 * java.lang.invoke.MethodHandles.Lookup::defineHiddenClass}
116 * </ul>
117 *
118 * <p> The methods of class {@code Class} expose many characteristics of a
119 * class or interface. Most characteristics are derived from the {@code class}
120 * file that the class loader passed to the Java Virtual Machine or
121 * from the {@code class} file passed to {@code Lookup::defineClass}
122 * or {@code Lookup::defineHiddenClass}.
123 * A few characteristics are determined by the class loading environment
124 * at run time, such as the module returned by {@link #getModule() getModule()}.
125 *
126 * <p> The following example uses a {@code Class} object to print the
127 * class name of an object:
128 *
129 * {@snippet lang="java" :
130 * void printClassName(Object obj) {
131 * System.out.println("The class of " + obj +
132 * " is " + obj.getClass().getName());
133 * }}
134 *
135 * It is also possible to get the {@code Class} object for a named
136 * class or interface (or for {@code void}) using a <dfn>class literal</dfn>
137 * (JLS {@jls 15.8.2}).
138 * For example:
139 *
140 * {@snippet lang="java" :
141 * System.out.println("The name of class Foo is: " + Foo.class.getName()); // @highlight substring="Foo.class"
142 * }
143 *
144 * <p> Some methods of class {@code Class} expose whether the declaration of
145 * a class or interface in Java source code was <em>enclosed</em> within
146 * another declaration. Other methods describe how a class or interface
147 * is situated in a <dfn>{@index "nest"}</dfn>. A nest is a set of
148 * classes and interfaces, in the same run-time package, that
149 * allow mutual access to their {@code private} members.
150 * The classes and interfaces are known as <dfn>{@index "nestmates"}</dfn>
151 * (JVMS {@jvms 4.7.29}).
152 * One nestmate acts as the
153 * <dfn>nest host</dfn> (JVMS {@jvms 4.7.28}), and enumerates the other nestmates which
154 * belong to the nest; each of them in turn records it as the nest host.
155 * The classes and interfaces which belong to a nest, including its host, are
156 * determined when
157 * {@code class} files are generated, for example, a Java compiler
158 * will typically record a top-level class as the host of a nest where the
159 * other members are the classes and interfaces whose declarations are
160 * enclosed within the top-level class declaration.
161 *
162 * <h2><a id=hiddenClasses>Hidden Classes</a></h2>
163 * A class or interface created by the invocation of
164 * {@link java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
165 * Lookup::defineHiddenClass} is a {@linkplain Class#isHidden() <dfn>hidden</dfn>}
166 * class or interface.
167 * All kinds of class, including enum classes and record classes, may be
168 * hidden classes; all kinds of interface, including annotation interfaces,
169 * may be hidden interfaces.
170 *
171 * The {@linkplain #getName() name of a hidden class or interface} is
172 * not a {@linkplain ClassLoader##binary-name binary name},
173 * which means the following:
174 * <ul>
175 * <li>A hidden class or interface cannot be referenced by the constant pools
176 * of other classes and interfaces.
177 * <li>A hidden class or interface cannot be described in
178 * {@linkplain java.lang.constant.ConstantDesc <em>nominal form</em>} by
179 * {@link #describeConstable() Class::describeConstable},
180 * {@link ClassDesc#of(String) ClassDesc::of}, or
181 * {@link ClassDesc#ofDescriptor(String) ClassDesc::ofDescriptor}.
182 * <li>A hidden class or interface cannot be discovered by {@link #forName Class::forName}
183 * or {@link ClassLoader#loadClass(String, boolean) ClassLoader::loadClass}.
184 * </ul>
185 *
186 * A hidden class or interface is never an array class, but may be
187 * the element type of an array. In all other respects, the fact that
188 * a class or interface is hidden has no bearing on the characteristics
189 * exposed by the methods of class {@code Class}.
190 *
191 * <h2><a id=implicitClasses>Implicitly Declared Classes</a></h2>
192 *
193 * Conventionally, a Java compiler, starting from a source file for an
194 * implicitly declared class, say {@code HelloWorld.java}, creates a
195 * similarly-named {@code class} file, {@code HelloWorld.class}, where
196 * the class stored in that {@code class} file is named {@code
197 * "HelloWorld"}, matching the base names of the source and {@code
198 * class} files.
199 *
200 * For the {@code Class} object of an implicitly declared class {@code
201 * HelloWorld}, the methods to get the {@linkplain #getName name} and
202 * {@linkplain #getTypeName type name} return results
203 * equal to {@code "HelloWorld"}. The {@linkplain #getSimpleName
204 * simple name} of such an implicitly declared class is {@code "HelloWorld"} and
205 * the {@linkplain #getCanonicalName canonical name} is {@code "HelloWorld"}.
206 *
207 * @param <T> the type of the class modeled by this {@code Class}
208 * object. For example, the type of {@code String.class} is {@code
209 * Class<String>}. Use {@code Class<?>} if the class being modeled is
210 * unknown.
211 *
212 * @see java.lang.ClassLoader#defineClass(byte[], int, int)
213 * @since 1.0
214 */
215 @AOTSafeClassInitializer
216 public final class Class<T> implements java.io.Serializable,
217 GenericDeclaration,
218 Type,
219 AnnotatedElement,
220 TypeDescriptor.OfField<Class<?>>,
221 Constable {
222 private static final int ANNOTATION= 0x00002000;
223 private static final int ENUM = 0x00004000;
224 private static final int SYNTHETIC = 0x00001000;
225
226 private static native void registerNatives();
227 static {
228 runtimeSetup();
229 }
230
231 /// No significant static final fields; [#resetArchivedStates()] handles
232 /// prevents storing [#reflectionFactory] into AOT image.
233 @AOTRuntimeSetup
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, char flags) {
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 classFileAccessFlags = flags;
253 }
254
255 /**
256 * Converts the object to a string. The string representation is the
257 * string "class" or "interface", followed by a space, and then by the
258 * name of the class in the format returned by {@code getName}.
259 * If this {@code Class} object represents a primitive type,
260 * this method returns the name of the primitive type. If
261 * this {@code Class} object represents void this method returns
262 * "void". If this {@code Class} object represents an array type,
263 * this method returns "class " followed by {@code getName}.
264 *
265 * @return a string representation of this {@code Class} object.
266 */
267 public String toString() {
268 String kind = isInterface() ? "interface " : isPrimitive() ? "" : "class ";
269 return kind.concat(getName());
270 }
271
272 /**
273 * Returns a string describing this {@code Class}, including
274 * information about modifiers, {@link #isSealed() sealed}/{@code
275 * non-sealed} status, and type parameters.
276 *
277 * The string is formatted as a list of type modifiers, if any,
278 * followed by the kind of type (empty string for primitive types
279 * and {@code class}, {@code enum}, {@code interface},
280 * {@code @interface}, or {@code record} as appropriate), followed
281 * by the type's name, followed by an angle-bracketed
282 * comma-separated list of the type's type parameters, if any,
283 * including informative bounds on the type parameters, if any.
284 *
285 * A space is used to separate modifiers from one another and to
286 * separate any modifiers from the kind of type. The modifiers
287 * occur in canonical order. If there are no type parameters, the
288 * type parameter list is elided.
289 *
290 * For an array type, the string starts with the type name,
291 * followed by an angle-bracketed comma-separated list of the
292 * type's type parameters, if any, followed by a sequence of
293 * {@code []} characters, one set of brackets per dimension of
294 * the array.
295 *
296 * <p>Note that since information about the runtime representation
297 * of a type is being generated, modifiers not present on the
298 * originating source code or illegal on the originating source
299 * code may be present.
300 *
301 * @return a string describing this {@code Class}, including
302 * information about modifiers and type parameters
303 *
304 * @since 1.8
305 */
306 public String toGenericString() {
307 if (isPrimitive()) {
308 return toString();
309 } else {
310 StringBuilder sb = new StringBuilder();
311 Class<?> component = this;
312 int arrayDepth = 0;
313
314 if (isArray()) {
315 do {
316 arrayDepth++;
317 component = component.getComponentType();
318 } while (component.isArray());
319 sb.append(component.getName());
320 } else {
321 // Class modifiers are a superset of interface modifiers
322 int modifiers = getModifiers() & Modifier.classModifiers();
323 if (modifiers != 0) {
324 sb.append(Modifier.toString(modifiers));
325 sb.append(' ');
326 }
327
328 // A class cannot be strictfp and sealed/non-sealed so
329 // it is sufficient to check for sealed-ness after all
330 // modifiers are printed.
331 addSealingInfo(modifiers, sb);
332
333 if (isAnnotation()) {
334 sb.append('@');
335 }
336 if (isInterface()) { // Note: all annotation interfaces are interfaces
337 sb.append("interface");
338 } else {
339 if (isEnum())
340 sb.append("enum");
341 else if (isRecord())
342 sb.append("record");
343 else
344 sb.append("class");
345 }
346 sb.append(' ');
347 sb.append(getName());
348 }
349
350 TypeVariable<?>[] typeparms = component.getTypeParameters();
351 if (typeparms.length > 0) {
352 sb.append(Arrays.stream(typeparms)
353 .map(Class::typeVarBounds)
354 .collect(Collectors.joining(",", "<", ">")));
355 }
356
357 if (arrayDepth > 0) sb.append("[]".repeat(arrayDepth));
358
359 return sb.toString();
360 }
361 }
362
363 private void addSealingInfo(int modifiers, StringBuilder sb) {
364 // A class can be final XOR sealed XOR non-sealed.
365 if (Modifier.isFinal(modifiers)) {
366 return; // no-op
367 } else {
368 if (isSealed()) {
369 sb.append("sealed ");
370 return;
371 } else {
372 // Check for sealed ancestor, which implies this class
373 // is non-sealed.
374 if (hasSealedAncestor(this)) {
375 sb.append("non-sealed ");
376 }
377 }
378 }
379 }
380
381 private boolean hasSealedAncestor(Class<?> clazz) {
382 // From JLS 8.1.1.2:
383 // "It is a compile-time error if a class has a sealed direct
384 // superclass or a sealed direct superinterface, and is not
385 // declared final, sealed, or non-sealed either explicitly or
386 // implicitly.
387 // Thus, an effect of the sealed keyword is to force all
388 // direct subclasses to explicitly declare whether they are
389 // final, sealed, or non-sealed. This avoids accidentally
390 // exposing a sealed class hierarchy to unwanted subclassing."
391
392 // Therefore, will just check direct superclass and
393 // superinterfaces.
394 var superclass = clazz.getSuperclass();
395 if (superclass != null && superclass.isSealed()) {
396 return true;
397 }
398 for (var superinterface : clazz.getInterfaces()) {
399 if (superinterface.isSealed()) {
400 return true;
401 }
402 }
403 return false;
404 }
405
406 static String typeVarBounds(TypeVariable<?> typeVar) {
407 Type[] bounds = typeVar.getBounds();
408 if (bounds.length == 1 && bounds[0].equals(Object.class)) {
409 return typeVar.getName();
410 } else {
411 return typeVar.getName() + " extends " +
412 Arrays.stream(bounds)
413 .map(Type::getTypeName)
414 .collect(Collectors.joining(" & "));
415 }
416 }
417
418 /**
419 * Returns the {@code Class} object associated with the class or
420 * interface with the given string name. Invoking this method is
421 * equivalent to:
422 *
423 * {@snippet lang="java" :
424 * Class.forName(className, true, currentLoader)
425 * }
426 *
427 * where {@code currentLoader} denotes the defining class loader of
428 * the current class.
429 *
430 * <p> For example, the following code fragment returns the
431 * runtime {@code Class} object for the class named
432 * {@code java.lang.Thread}:
433 *
434 * {@snippet lang="java" :
435 * Class<?> t = Class.forName("java.lang.Thread");
436 * }
437 * <p>
438 * A call to {@code forName("X")} causes the class named
439 * {@code X} to be initialized.
440 *
441 * <p>
442 * In cases where this method is called from a context where there is no
443 * caller frame on the stack (e.g. when called directly from a JNI
444 * attached thread), the system class loader is used.
445 *
446 * @param className the {@linkplain ClassLoader##binary-name binary name}
447 * of the class or the string representing an array type
448 * @return the {@code Class} object for the class with the
449 * specified name.
450 * @throws LinkageError if the linkage fails
451 * @throws ExceptionInInitializerError if the initialization provoked
452 * by this method fails
453 * @throws ClassNotFoundException if the class cannot be located
454 *
455 * @jls 12.2 Loading of Classes and Interfaces
456 * @jls 12.3 Linking of Classes and Interfaces
457 * @jls 12.4 Initialization of Classes and Interfaces
458 */
459 @CallerSensitive
460 public static Class<?> forName(String className)
461 throws ClassNotFoundException {
462 Class<?> caller = Reflection.getCallerClass();
463 return forName(className, caller);
464 }
465
466 // Caller-sensitive adapter method for reflective invocation
467 @CallerSensitiveAdapter
468 private static Class<?> forName(String className, Class<?> caller)
469 throws ClassNotFoundException {
470 ClassLoader loader = (caller == null) ? ClassLoader.getSystemClassLoader()
471 : ClassLoader.getClassLoader(caller);
472 if (loader instanceof BuiltinClassLoader bcl) {
473 if (bcl.usePositiveCache) {
474 Class<?> result = bcl.checkPositiveLookupCache(className);
475 if (result != null) {
476 // forName(String, Class) API will always initialize the class
477 Unsafe.getUnsafe().ensureClassInitialized(result);
478 return result;
479 }
480 }
481 if (bcl.useNegativeCache && bcl.checkNegativeLookupCache(className)) {
482 throw new ClassNotFoundException(className);
483 }
484 }
485 return forName0(className, true, loader, caller);
486 }
487
488 /**
489 * Returns the {@code Class} object associated with the class or
490 * interface with the given string name, using the given class loader.
491 * Given the {@linkplain ClassLoader##binary-name binary name} for a class or interface,
492 * this method attempts to locate and load the class or interface. The specified
493 * class loader is used to load the class or interface. If the parameter
494 * {@code loader} is {@code null}, the class is loaded through the bootstrap
495 * class loader. The class is initialized only if the
496 * {@code initialize} parameter is {@code true} and if it has
497 * not been initialized earlier.
498 *
499 * <p> This method cannot be used to obtain any of the {@code Class} objects
500 * representing primitive types or void, hidden classes or interfaces,
501 * or array classes whose element type is a hidden class or interface.
502 * If {@code name} denotes a primitive type or void, for example {@code I},
503 * an attempt will be made to locate a user-defined class in the unnamed package
504 * whose name is {@code I} instead.
505 * To obtain a {@code Class} object for a named primitive type
506 * such as {@code int} or {@code long} use {@link
507 * #forPrimitiveName(String)}.
508 *
509 * <p> To obtain the {@code Class} object associated with an array class,
510 * the name consists of one or more {@code '['} representing the depth
511 * of the array nesting, followed by the element type as encoded in
512 * {@linkplain ##nameFormat the table} specified in {@code Class.getName()}.
513 *
514 * <p> Examples:
515 * {@snippet lang="java" :
516 * Class<?> threadClass = Class.forName("java.lang.Thread", false, currentLoader);
517 * Class<?> stringArrayClass = Class.forName("[Ljava.lang.String;", false, currentLoader);
518 * Class<?> intArrayClass = Class.forName("[[[I", false, currentLoader); // Class of int[][][]
519 * Class<?> nestedClass = Class.forName("java.lang.Character$UnicodeBlock", false, currentLoader);
520 * Class<?> fooClass = Class.forName("Foo", true, currentLoader);
521 * }
522 *
523 * <p> A call to {@code getName()} on the {@code Class} object returned
524 * from {@code forName(}<i>N</i>{@code )} returns <i>N</i>.
525 *
526 * <p> A call to {@code forName("[L}<i>N</i>{@code ;")} causes the element type
527 * named <i>N</i> to be loaded but not initialized regardless of the value
528 * of the {@code initialize} parameter.
529 *
530 * @apiNote
531 * This method throws errors related to loading, linking or initializing
532 * as specified in Sections {@jls 12.2}, {@jls 12.3}, and {@jls 12.4} of
533 * <cite>The Java Language Specification</cite>.
534 * In addition, this method does not check whether the requested class
535 * is accessible to its caller.
536 *
537 * @param name the {@linkplain ClassLoader##binary-name binary name}
538 * of the class or the string representing an array class
539 *
540 * @param initialize if {@code true} the class will be initialized
541 * (which implies linking). See Section {@jls
542 * 12.4} of <cite>The Java Language
543 * Specification</cite>.
544 * @param loader class loader from which the class must be loaded
545 * @return class object representing the desired class
546 *
547 * @throws LinkageError if the linkage fails
548 * @throws ExceptionInInitializerError if the initialization provoked
549 * by this method fails
550 * @throws ClassNotFoundException if the class cannot be located by
551 * the specified class loader
552 *
553 * @see java.lang.Class#forName(String)
554 * @see java.lang.ClassLoader
555 *
556 * @jls 12.2 Loading of Classes and Interfaces
557 * @jls 12.3 Linking of Classes and Interfaces
558 * @jls 12.4 Initialization of Classes and Interfaces
559 * @jls 13.1 The Form of a Binary
560 * @since 1.2
561 */
562 public static Class<?> forName(String name, boolean initialize, ClassLoader loader)
563 throws ClassNotFoundException
564 {
565 if (loader instanceof BuiltinClassLoader bcl) {
566 if (bcl.usePositiveCache) {
567 Class<?> result = bcl.checkPositiveLookupCache(name);
568 if (result != null) {
569 if (initialize) {
570 Unsafe.getUnsafe().ensureClassInitialized(result);
571 }
572 return result;
573 }
574 }
575 if (bcl.useNegativeCache && bcl.checkNegativeLookupCache(name)) {
576 throw new ClassNotFoundException(name);
577 }
578 }
579 return forName0(name, initialize, loader, null);
580 }
581
582 /** Called after security check for system loader access checks have been made. */
583 private static native Class<?> forName0(String name, boolean initialize,
584 ClassLoader loader,
585 Class<?> caller)
586 throws ClassNotFoundException;
587
588
589 /**
590 * Returns the {@code Class} with the given {@linkplain ClassLoader##binary-name
591 * binary name} in the given module.
592 *
593 * <p> This method attempts to locate and load the class or interface.
594 * It does not link the class, and does not run the class initializer.
595 * If the class is not found, this method returns {@code null}. </p>
596 *
597 * <p> If the class loader of the given module defines other modules and
598 * the given name is a class defined in a different module, this method
599 * returns {@code null} after the class is loaded. </p>
600 *
601 * <p> This method does not check whether the requested class is
602 * accessible to its caller. </p>
603 *
604 * @apiNote
605 * This method does not support loading of array types, unlike
606 * {@link #forName(String, boolean, ClassLoader)}. The class name must be
607 * a binary name. This method returns {@code null} on failure rather than
608 * throwing a {@link ClassNotFoundException}, as is done by
609 * the {@link #forName(String, boolean, ClassLoader)} method.
610 *
611 * @param module A module
612 * @param name The {@linkplain ClassLoader##binary-name binary name}
613 * of the class
614 * @return {@code Class} object of the given name defined in the given module;
615 * {@code null} if not found.
616 *
617 * @throws NullPointerException if the given module or name is {@code null}
618 *
619 * @throws LinkageError if the linkage fails
620 *
621 * @jls 12.2 Loading of Classes and Interfaces
622 * @jls 12.3 Linking of Classes and Interfaces
623 * @since 9
624 */
625 public static Class<?> forName(Module module, String name) {
626 Objects.requireNonNull(module);
627 Objects.requireNonNull(name);
628
629 ClassLoader cl = module.getClassLoader();
630 if (cl != null) {
631 return cl.loadClass(module, name);
632 } else {
633 return BootLoader.loadClass(module, name);
634 }
635 }
636
637 /**
638 * {@return the {@code Class} object associated with the
639 * {@linkplain #isPrimitive() primitive type} of the given name}
640 * If the argument is not the name of a primitive type, {@code
641 * null} is returned.
642 *
643 * @param primitiveName the name of the primitive type to find
644 *
645 * @throws NullPointerException if the argument is {@code null}
646 *
647 * @jls 4.2 Primitive Types and Values
648 * @jls 15.8.2 Class Literals
649 * @since 22
650 */
651 public static Class<?> forPrimitiveName(String primitiveName) {
652 return switch(primitiveName) {
653 // Integral types
654 case "int" -> int.class;
655 case "long" -> long.class;
656 case "short" -> short.class;
657 case "char" -> char.class;
658 case "byte" -> byte.class;
659
660 // Floating-point types
661 case "float" -> float.class;
662 case "double" -> double.class;
663
664 // Other types
665 case "boolean" -> boolean.class;
666 case "void" -> void.class;
667
668 default -> null;
669 };
670 }
671
672 /**
673 * Creates a new instance of the class represented by this {@code Class}
674 * object. The class is instantiated as if by a {@code new}
675 * expression with an empty argument list. The class is initialized if it
676 * has not already been initialized.
677 *
678 * @deprecated This method propagates any exception thrown by the
679 * nullary constructor, including a checked exception. Use of
680 * this method effectively bypasses the compile-time exception
681 * checking that would otherwise be performed by the compiler.
682 * The {@link
683 * java.lang.reflect.Constructor#newInstance(java.lang.Object...)
684 * Constructor.newInstance} method avoids this problem by wrapping
685 * any exception thrown by the constructor in a (checked) {@link
686 * java.lang.reflect.InvocationTargetException}.
687 *
688 * <p>The call
689 *
690 * {@snippet lang="java" :
691 * clazz.newInstance()
692 * }
693 *
694 * can be replaced by
695 *
696 * {@snippet lang="java" :
697 * clazz.getDeclaredConstructor().newInstance()
698 * }
699 *
700 * The latter sequence of calls is inferred to be able to throw
701 * the additional exception types {@link
702 * InvocationTargetException} and {@link
703 * NoSuchMethodException}. Both of these exception types are
704 * subclasses of {@link ReflectiveOperationException}.
705 *
706 * @return a newly allocated instance of the class represented by this
707 * object.
708 * @throws IllegalAccessException if the class or its nullary
709 * constructor is not accessible.
710 * @throws InstantiationException
711 * if this {@code Class} represents an abstract class,
712 * an interface, an array class, a primitive type, or void;
713 * or if the class has no nullary constructor;
714 * or if the instantiation fails for some other reason.
715 * @throws ExceptionInInitializerError if the initialization
716 * provoked by this method fails.
717 */
718 @CallerSensitive
719 @Deprecated(since="9")
720 public T newInstance()
721 throws InstantiationException, IllegalAccessException
722 {
723 // Constructor lookup
724 Constructor<T> tmpConstructor = cachedConstructor;
725 if (tmpConstructor == null) {
726 if (this == Class.class) {
727 throw new IllegalAccessException(
728 "Can not call newInstance() on the Class for java.lang.Class"
729 );
730 }
731 try {
732 Class<?>[] empty = {};
733 final Constructor<T> c = getReflectionFactory().copyConstructor(
734 getConstructor0(empty, Member.DECLARED));
735 // Disable accessibility checks on the constructor
736 // access check is done with the true caller
737 c.setAccessible(true);
738 cachedConstructor = tmpConstructor = c;
739 } catch (NoSuchMethodException e) {
740 throw (InstantiationException)
741 new InstantiationException(getName()).initCause(e);
742 }
743 }
744
745 try {
746 Class<?> caller = Reflection.getCallerClass();
747 return getReflectionFactory().newInstance(tmpConstructor, null, caller);
748 } catch (InvocationTargetException e) {
749 Unsafe.getUnsafe().throwException(e.getTargetException());
750 // Not reached
751 return null;
752 }
753 }
754
755 private transient volatile Constructor<T> cachedConstructor;
756
757 /**
758 * Determines if the specified {@code Object} is assignment-compatible
759 * with the object represented by this {@code Class}. This method is
760 * the dynamic equivalent of the Java language {@code instanceof}
761 * operator. The method returns {@code true} if the specified
762 * {@code Object} argument is non-null and can be cast to the
763 * reference type represented by this {@code Class} object without
764 * raising a {@code ClassCastException.} It returns {@code false}
765 * otherwise.
766 *
767 * <p> Specifically, if this {@code Class} object represents a
768 * declared class, this method returns {@code true} if the specified
769 * {@code Object} argument is an instance of the represented class (or
770 * of any of its subclasses); it returns {@code false} otherwise. If
771 * this {@code Class} object represents an array class, this method
772 * returns {@code true} if the specified {@code Object} argument
773 * can be converted to an object of the array class by an identity
774 * conversion or by a widening reference conversion; it returns
775 * {@code false} otherwise. If this {@code Class} object
776 * represents an interface, this method returns {@code true} if the
777 * class or any superclass of the specified {@code Object} argument
778 * implements this interface; it returns {@code false} otherwise. If
779 * this {@code Class} object represents a primitive type, this method
780 * returns {@code false}.
781 *
782 * @param obj the object to check
783 * @return true if {@code obj} is an instance of this class
784 *
785 * @since 1.1
786 */
787 @IntrinsicCandidate
788 public native boolean isInstance(Object obj);
789
790
791 /**
792 * Determines if the class or interface represented by this
793 * {@code Class} object is either the same as, or is a superclass or
794 * superinterface of, the class or interface represented by the specified
795 * {@code Class} parameter. It returns {@code true} if so;
796 * otherwise it returns {@code false}. If this {@code Class}
797 * object represents a primitive type, this method returns
798 * {@code true} if the specified {@code Class} parameter is
799 * exactly this {@code Class} object; otherwise it returns
800 * {@code false}.
801 *
802 * <p> Specifically, this method tests whether the type represented by the
803 * specified {@code Class} parameter can be converted to the type
804 * represented by this {@code Class} object via an identity conversion
805 * or via a widening reference conversion. See <cite>The Java Language
806 * Specification</cite>, sections {@jls 5.1.1} and {@jls 5.1.4},
807 * for details.
808 *
809 * @param cls the {@code Class} object to be checked
810 * @return the {@code boolean} value indicating whether objects of the
811 * type {@code cls} can be assigned to objects of this class
812 * @throws NullPointerException if the specified Class parameter is
813 * null.
814 * @since 1.1
815 */
816 @IntrinsicCandidate
817 public native boolean isAssignableFrom(Class<?> cls);
818
819
820 /**
821 * Determines if this {@code Class} object represents an
822 * interface type.
823 *
824 * @return {@code true} if this {@code Class} object represents an interface;
825 * {@code false} otherwise.
826 */
827 public boolean isInterface() {
828 return Modifier.isInterface(modifiers);
829 }
830
831
832 /**
833 * Determines if this {@code Class} object represents an array class.
834 *
835 * @return {@code true} if this {@code Class} object represents an array class;
836 * {@code false} otherwise.
837 * @since 1.1
838 */
839 public boolean isArray() {
840 return componentType != null;
841 }
842
843
844 /**
845 * Determines if this {@code Class} object represents a primitive
846 * type or void.
847 *
848 * <p> There are nine predefined {@code Class} objects to
849 * represent the eight primitive types and void. These are
850 * created by the Java Virtual Machine, and have the same
851 * {@linkplain #getName() names} as the primitive types that they
852 * represent, namely {@code boolean}, {@code byte}, {@code char},
853 * {@code short}, {@code int}, {@code long}, {@code float}, and
854 * {@code double}.
855 *
856 * <p>No other class objects are considered primitive.
857 *
858 * @apiNote
859 * A {@code Class} object represented by a primitive type can be
860 * accessed via the {@code TYPE} public static final variables
861 * defined in the primitive wrapper classes such as {@link
862 * java.lang.Integer#TYPE Integer.TYPE}. In the Java programming
863 * language, the objects may be referred to by a class literal
864 * expression such as {@code int.class}. The {@code Class} object
865 * for void can be expressed as {@code void.class} or {@link
866 * java.lang.Void#TYPE Void.TYPE}.
867 *
868 * @return true if and only if this class represents a primitive type
869 *
870 * @see java.lang.Boolean#TYPE
871 * @see java.lang.Character#TYPE
872 * @see java.lang.Byte#TYPE
873 * @see java.lang.Short#TYPE
874 * @see java.lang.Integer#TYPE
875 * @see java.lang.Long#TYPE
876 * @see java.lang.Float#TYPE
877 * @see java.lang.Double#TYPE
878 * @see java.lang.Void#TYPE
879 * @since 1.1
880 * @jls 15.8.2 Class Literals
881 */
882 public boolean isPrimitive() {
883 return primitive;
884 }
885
886 /**
887 * Returns true if this {@code Class} object represents an annotation
888 * interface. Note that if this method returns true, {@link #isInterface()}
889 * would also return true, as all annotation interfaces are also interfaces.
890 *
891 * @return {@code true} if this {@code Class} object represents an annotation
892 * interface; {@code false} otherwise
893 * @since 1.5
894 */
895 public boolean isAnnotation() {
896 return (getModifiers() & ANNOTATION) != 0;
897 }
898
899 /**
900 *{@return {@code true} if and only if this class has the synthetic modifier
901 * bit set}
902 *
903 * @jls 13.1 The Form of a Binary
904 * @jvms 4.1 The {@code ClassFile} Structure
905 * @see <a
906 * href="{@docRoot}/java.base/java/lang/reflect/package-summary.html#LanguageJvmModel">Java
907 * programming language and JVM modeling in core reflection</a>
908 * @since 1.5
909 */
910 public boolean isSynthetic() {
911 return (getModifiers() & SYNTHETIC) != 0;
912 }
913
914 /**
915 * Returns the name of the entity (class, interface, array class,
916 * primitive type, or void) represented by this {@code Class} object.
917 *
918 * <p> If this {@code Class} object represents a class or interface,
919 * not an array class, then:
920 * <ul>
921 * <li> If the class or interface is not {@linkplain #isHidden() hidden},
922 * then the {@linkplain ClassLoader##binary-name binary name}
923 * of the class or interface is returned.
924 * <li> If the class or interface is hidden, then the result is a string
925 * of the form: {@code N + '/' + <suffix>}
926 * where {@code N} is the {@linkplain ClassLoader##binary-name binary name}
927 * indicated by the {@code class} file passed to
928 * {@link java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
929 * Lookup::defineHiddenClass}, and {@code <suffix>} is an unqualified name.
930 * </ul>
931 *
932 * <p> If this {@code Class} object represents an array class, then
933 * the result is a string consisting of one or more '{@code [}' characters
934 * representing the depth of the array nesting, followed by the element
935 * type as encoded using the following table:
936 *
937 * <blockquote><table class="striped" id="nameFormat">
938 * <caption style="display:none">Element types and encodings</caption>
939 * <thead>
940 * <tr><th scope="col"> Element Type <th scope="col"> Encoding
941 * </thead>
942 * <tbody style="text-align:left">
943 * <tr><th scope="row"> {@code boolean} <td style="text-align:center"> {@code Z}
944 * <tr><th scope="row"> {@code byte} <td style="text-align:center"> {@code B}
945 * <tr><th scope="row"> {@code char} <td style="text-align:center"> {@code C}
946 * <tr><th scope="row"> class or interface with {@linkplain ClassLoader##binary-name binary name} <i>N</i>
947 * <td style="text-align:center"> {@code L}<em>N</em>{@code ;}
948 * <tr><th scope="row"> {@code double} <td style="text-align:center"> {@code D}
949 * <tr><th scope="row"> {@code float} <td style="text-align:center"> {@code F}
950 * <tr><th scope="row"> {@code int} <td style="text-align:center"> {@code I}
951 * <tr><th scope="row"> {@code long} <td style="text-align:center"> {@code J}
952 * <tr><th scope="row"> {@code short} <td style="text-align:center"> {@code S}
953 * </tbody>
954 * </table></blockquote>
955 *
956 * <p> If this {@code Class} object represents a primitive type or {@code void},
957 * then the result is a string with the same spelling as the Java language
958 * keyword which corresponds to the primitive type or {@code void}.
959 *
960 * <p> Examples:
961 * <blockquote><pre>
962 * String.class.getName()
963 * returns "java.lang.String"
964 * Character.UnicodeBlock.class.getName()
965 * returns "java.lang.Character$UnicodeBlock"
966 * byte.class.getName()
967 * returns "byte"
968 * (new Object[3]).getClass().getName()
969 * returns "[Ljava.lang.Object;"
970 * (new int[3][4][5][6][7][8][9]).getClass().getName()
971 * returns "[[[[[[[I"
972 * </pre></blockquote>
973 *
974 * @apiNote
975 * Distinct class objects can have the same name but different class loaders.
976 *
977 * @return the name of the class, interface, or other entity
978 * represented by this {@code Class} object.
979 * @jls 13.1 The Form of a Binary
980 */
981 public String getName() {
982 String name = this.name;
983 return name != null ? name : initClassName();
984 }
985
986 // Cache the name to reduce the number of calls into the VM.
987 // This field would be set by VM itself during initClassName call.
988 private transient String name;
989 private native String initClassName();
990
991 /**
992 * Returns the class loader for the class. Some implementations may use
993 * null to represent the bootstrap class loader. This method will return
994 * null in such implementations if this class was loaded by the bootstrap
995 * class loader.
996 *
997 * <p>If this {@code Class} object
998 * represents a primitive type or void, null is returned.
999 *
1000 * @return the class loader that loaded the class or interface
1001 * represented by this {@code Class} object.
1002 * @see java.lang.ClassLoader
1003 */
1004 public ClassLoader getClassLoader() {
1005 return classLoader;
1006 }
1007
1008 // Package-private to allow ClassLoader access
1009 ClassLoader getClassLoader0() { return classLoader; }
1010
1011 /**
1012 * Returns the module that this class or interface is a member of.
1013 *
1014 * If this class represents an array type then this method returns the
1015 * {@code Module} for the element type. If this class represents a
1016 * primitive type or void, then the {@code Module} object for the
1017 * {@code java.base} module is returned.
1018 *
1019 * If this class is in an unnamed module then the {@linkplain
1020 * ClassLoader#getUnnamedModule() unnamed} {@code Module} of the class
1021 * loader for this class is returned.
1022 *
1023 * @return the module that this class or interface is a member of
1024 *
1025 * @since 9
1026 */
1027 public Module getModule() {
1028 return module;
1029 }
1030
1031 // set by VM
1032 @Stable
1033 private transient Module module;
1034
1035 // Initialized in JVM not by private constructor
1036 // This field is filtered from reflection access, i.e. getDeclaredField
1037 // will throw NoSuchFieldException
1038 private final ClassLoader classLoader;
1039
1040 private transient Object classData; // Set by VM
1041 private transient Object[] signers; // Read by VM, mutable
1042 private final transient char modifiers; // Set by the VM
1043 private final transient char classFileAccessFlags; // Set by the VM
1044 private final transient boolean primitive; // Set by the VM if the Class is a primitive type.
1045
1046 // package-private
1047 Object getClassData() {
1048 return classData;
1049 }
1050
1051 /**
1052 * Returns an array of {@code TypeVariable} objects that represent the
1053 * type variables declared by the generic declaration represented by this
1054 * {@code GenericDeclaration} object, in declaration order. Returns an
1055 * array of length 0 if the underlying generic declaration declares no type
1056 * variables.
1057 *
1058 * @return an array of {@code TypeVariable} objects that represent
1059 * the type variables declared by this generic declaration
1060 * @throws java.lang.reflect.GenericSignatureFormatError if the generic
1061 * signature of this generic declaration does not conform to
1062 * the format specified in section {@jvms 4.7.9} of
1063 * <cite>The Java Virtual Machine Specification</cite>
1064 * @since 1.5
1065 */
1066 @SuppressWarnings("unchecked")
1067 public TypeVariable<Class<T>>[] getTypeParameters() {
1068 ClassRepository info = getGenericInfo();
1069 if (info != null)
1070 return (TypeVariable<Class<T>>[])info.getTypeParameters();
1071 else
1072 return (TypeVariable<Class<T>>[])new TypeVariable<?>[0];
1073 }
1074
1075
1076 /**
1077 * Returns the {@code Class} representing the direct superclass of the
1078 * entity (class, interface, primitive type or void) represented by
1079 * this {@code Class}. If this {@code Class} represents either the
1080 * {@code Object} class, an interface, a primitive type, or void, then
1081 * null is returned. If this {@code Class} object represents an array class
1082 * then the {@code Class} object representing the {@code Object} class is
1083 * returned.
1084 *
1085 * @return the direct superclass of the class represented by this {@code Class} object
1086 */
1087 @IntrinsicCandidate
1088 public native Class<? super T> getSuperclass();
1089
1090
1091 /**
1092 * Returns the {@code Type} representing the direct superclass of
1093 * the entity (class, interface, primitive type or void) represented by
1094 * this {@code Class} object.
1095 *
1096 * <p>If the superclass is a parameterized type, the {@code Type}
1097 * object returned must accurately reflect the actual type
1098 * arguments used in the source code. The parameterized type
1099 * representing the superclass is created if it had not been
1100 * created before. See the declaration of {@link
1101 * java.lang.reflect.ParameterizedType ParameterizedType} for the
1102 * semantics of the creation process for parameterized types. If
1103 * this {@code Class} object represents either the {@code Object}
1104 * class, an interface, a primitive type, or void, then null is
1105 * returned. If this {@code Class} object represents an array class
1106 * then the {@code Class} object representing the {@code Object} class is
1107 * returned.
1108 *
1109 * @throws java.lang.reflect.GenericSignatureFormatError if the generic
1110 * class signature does not conform to the format specified in
1111 * section {@jvms 4.7.9} of <cite>The Java Virtual
1112 * Machine Specification</cite>
1113 * @throws TypeNotPresentException if the generic superclass
1114 * refers to a non-existent type declaration
1115 * @throws java.lang.reflect.MalformedParameterizedTypeException if the
1116 * generic superclass refers to a parameterized type that cannot be
1117 * instantiated for any reason
1118 * @return the direct superclass of the class represented by this {@code Class} object
1119 * @since 1.5
1120 */
1121 public Type getGenericSuperclass() {
1122 ClassRepository info = getGenericInfo();
1123 if (info == null) {
1124 return getSuperclass();
1125 }
1126
1127 // Historical irregularity:
1128 // Generic signature marks interfaces with superclass = Object
1129 // but this API returns null for interfaces
1130 if (isInterface()) {
1131 return null;
1132 }
1133
1134 return info.getSuperclass();
1135 }
1136
1137 /**
1138 * Gets the package of this class.
1139 *
1140 * <p>If this class represents an array type, a primitive type or void,
1141 * this method returns {@code null}.
1142 *
1143 * @return the package of this class.
1144 */
1145 public Package getPackage() {
1146 if (isPrimitive() || isArray()) {
1147 return null;
1148 }
1149 ClassLoader cl = classLoader;
1150 return cl != null ? cl.definePackage(this)
1151 : BootLoader.definePackage(this);
1152 }
1153
1154 /**
1155 * Returns the fully qualified package name.
1156 *
1157 * <p> If this class is a top level class, then this method returns the fully
1158 * qualified name of the package that the class is a member of, or the
1159 * empty string if the class is in an unnamed package.
1160 *
1161 * <p> If this class is a member class, then this method is equivalent to
1162 * invoking {@code getPackageName()} on the {@linkplain #getEnclosingClass
1163 * enclosing class}.
1164 *
1165 * <p> If this class is a {@linkplain #isLocalClass local class} or an {@linkplain
1166 * #isAnonymousClass() anonymous class}, then this method is equivalent to
1167 * invoking {@code getPackageName()} on the {@linkplain #getDeclaringClass
1168 * declaring class} of the {@linkplain #getEnclosingMethod enclosing method} or
1169 * {@linkplain #getEnclosingConstructor enclosing constructor}.
1170 *
1171 * <p> If this class represents an array type then this method returns the
1172 * package name of the element type. If this class represents a primitive
1173 * type or void then the package name "{@code java.lang}" is returned.
1174 *
1175 * @return the fully qualified package name
1176 *
1177 * @since 9
1178 * @jls 6.7 Fully Qualified Names and Canonical Names
1179 */
1180 public String getPackageName() {
1181 String pn = this.packageName;
1182 if (pn == null) {
1183 Class<?> c = isArray() ? elementType() : this;
1184 if (c.isPrimitive()) {
1185 pn = "java.lang";
1186 } else {
1187 String cn = c.getName();
1188 int dot = cn.lastIndexOf('.');
1189 pn = (dot != -1) ? cn.substring(0, dot).intern() : "";
1190 }
1191 this.packageName = pn;
1192 }
1193 return pn;
1194 }
1195
1196 // cached package name
1197 private transient String packageName;
1198
1199 /**
1200 * Returns the interfaces directly implemented by the class or interface
1201 * represented by this {@code Class} object.
1202 *
1203 * <p>If this {@code Class} object represents a class, the return value is an array
1204 * containing objects representing all interfaces directly implemented by
1205 * the class. The order of the interface objects in the array corresponds
1206 * to the order of the interface names in the {@code implements} clause of
1207 * the declaration of the class represented by this {@code Class} object. For example,
1208 * given the declaration:
1209 * <blockquote>
1210 * {@code class Shimmer implements FloorWax, DessertTopping { ... }}
1211 * </blockquote>
1212 * suppose the value of {@code s} is an instance of
1213 * {@code Shimmer}; the value of the expression:
1214 * <blockquote>
1215 * {@code s.getClass().getInterfaces()[0]}
1216 * </blockquote>
1217 * is the {@code Class} object that represents interface
1218 * {@code FloorWax}; and the value of:
1219 * <blockquote>
1220 * {@code s.getClass().getInterfaces()[1]}
1221 * </blockquote>
1222 * is the {@code Class} object that represents interface
1223 * {@code DessertTopping}.
1224 *
1225 * <p>If this {@code Class} object represents an interface, the array contains objects
1226 * representing all interfaces directly extended by the interface. The
1227 * order of the interface objects in the array corresponds to the order of
1228 * the interface names in the {@code extends} clause of the declaration of
1229 * the interface represented by this {@code Class} object.
1230 *
1231 * <p>If this {@code Class} object represents a class or interface that implements no
1232 * interfaces, the method returns an array of length 0.
1233 *
1234 * <p>If this {@code Class} object represents a primitive type or void, the method
1235 * returns an array of length 0.
1236 *
1237 * <p>If this {@code Class} object represents an array type, the
1238 * interfaces {@code Cloneable} and {@code java.io.Serializable} are
1239 * returned in that order.
1240 *
1241 * @return an array of interfaces directly implemented by this class
1242 */
1243 public Class<?>[] getInterfaces() {
1244 // defensively copy before handing over to user code
1245 return getInterfaces(true);
1246 }
1247
1248 private Class<?>[] getInterfaces(boolean cloneArray) {
1249 ReflectionData<T> rd = reflectionData();
1250 Class<?>[] interfaces = rd.interfaces;
1251 if (interfaces == null) {
1252 interfaces = getInterfaces0();
1253 rd.interfaces = interfaces;
1254 }
1255 // defensively copy if requested
1256 return cloneArray ? interfaces.clone() : interfaces;
1257 }
1258
1259 private native Class<?>[] getInterfaces0();
1260
1261 /**
1262 * Returns the {@code Type}s representing the interfaces
1263 * directly implemented by the class or interface represented by
1264 * this {@code Class} object.
1265 *
1266 * <p>If a superinterface is a parameterized type, the
1267 * {@code Type} object returned for it must accurately reflect
1268 * the actual type arguments used in the source code. The
1269 * parameterized type representing each superinterface is created
1270 * if it had not been created before. See the declaration of
1271 * {@link java.lang.reflect.ParameterizedType ParameterizedType}
1272 * for the semantics of the creation process for parameterized
1273 * types.
1274 *
1275 * <p>If this {@code Class} object represents a class, the return value is an array
1276 * containing objects representing all interfaces directly implemented by
1277 * the class. The order of the interface objects in the array corresponds
1278 * to the order of the interface names in the {@code implements} clause of
1279 * the declaration of the class represented by this {@code Class} object.
1280 *
1281 * <p>If this {@code Class} object represents an interface, the array contains objects
1282 * representing all interfaces directly extended by the interface. The
1283 * order of the interface objects in the array corresponds to the order of
1284 * the interface names in the {@code extends} clause of the declaration of
1285 * the interface represented by this {@code Class} object.
1286 *
1287 * <p>If this {@code Class} object represents a class or interface that implements no
1288 * interfaces, the method returns an array of length 0.
1289 *
1290 * <p>If this {@code Class} object represents a primitive type or void, the method
1291 * returns an array of length 0.
1292 *
1293 * <p>If this {@code Class} object represents an array type, the
1294 * interfaces {@code Cloneable} and {@code java.io.Serializable} are
1295 * returned in that order.
1296 *
1297 * @throws java.lang.reflect.GenericSignatureFormatError
1298 * if the generic class signature does not conform to the
1299 * format specified in section {@jvms 4.7.9} of <cite>The
1300 * Java Virtual Machine Specification</cite>
1301 * @throws TypeNotPresentException if any of the generic
1302 * superinterfaces refers to a non-existent type declaration
1303 * @throws java.lang.reflect.MalformedParameterizedTypeException
1304 * if any of the generic superinterfaces refer to a parameterized
1305 * type that cannot be instantiated for any reason
1306 * @return an array of interfaces directly implemented by this class
1307 * @since 1.5
1308 */
1309 public Type[] getGenericInterfaces() {
1310 ClassRepository info = getGenericInfo();
1311 return (info == null) ? getInterfaces() : info.getSuperInterfaces();
1312 }
1313
1314
1315 /**
1316 * Returns the {@code Class} representing the component type of an
1317 * array. If this class does not represent an array class this method
1318 * returns null.
1319 *
1320 * @return the {@code Class} representing the component type of this
1321 * class if this class is an array
1322 * @see java.lang.reflect.Array
1323 * @since 1.1
1324 */
1325 public Class<?> getComponentType() {
1326 return componentType;
1327 }
1328
1329 // The componentType field's null value is the sole indication that the class
1330 // is an array - see isArray().
1331 private transient final Class<?> componentType;
1332
1333 /*
1334 * Returns the {@code Class} representing the element type of an array class.
1335 * If this class does not represent an array class, then this method returns
1336 * {@code null}.
1337 */
1338 private Class<?> elementType() {
1339 if (!isArray()) return null;
1340
1341 Class<?> c = this;
1342 while (c.isArray()) {
1343 c = c.getComponentType();
1344 }
1345 return c;
1346 }
1347
1348 /**
1349 * Returns the Java language modifiers for this class or interface, encoded
1350 * in an integer. The modifiers consist of the Java Virtual Machine's
1351 * constants for {@code public}, {@code protected},
1352 * {@code private}, {@code final}, {@code static},
1353 * {@code abstract} and {@code interface}; they should be decoded
1354 * using the methods of class {@code Modifier}.
1355 *
1356 * <p> If the underlying class is an array class:
1357 * <ul>
1358 * <li> its {@code public}, {@code private} and {@code protected}
1359 * modifiers are the same as those of its component type
1360 * <li> its {@code abstract} and {@code final} modifiers are always
1361 * {@code true}
1362 * <li> its interface modifier is always {@code false}, even when
1363 * the component type is an interface
1364 * </ul>
1365 * If this {@code Class} object represents a primitive type or
1366 * void, its {@code public}, {@code abstract}, and {@code final}
1367 * modifiers are always {@code true}.
1368 * For {@code Class} objects representing void, primitive types, and
1369 * arrays, the values of other modifiers are {@code false} other
1370 * than as specified above.
1371 *
1372 * <p> The modifier encodings are defined in section {@jvms 4.1}
1373 * of <cite>The Java Virtual Machine Specification</cite>.
1374 *
1375 * @return the {@code int} representing the modifiers for this class
1376 * @see java.lang.reflect.Modifier
1377 * @see #accessFlags()
1378 * @see <a
1379 * href="{@docRoot}/java.base/java/lang/reflect/package-summary.html#LanguageJvmModel">Java
1380 * programming language and JVM modeling in core reflection</a>
1381 * @since 1.1
1382 * @jls 8.1.1 Class Modifiers
1383 * @jls 9.1.1 Interface Modifiers
1384 * @jvms 4.1 The {@code ClassFile} Structure
1385 */
1386 public int getModifiers() { return modifiers; }
1387
1388 /**
1389 * {@return an unmodifiable set of the {@linkplain AccessFlag access
1390 * flags} for this class, possibly empty}
1391 *
1392 * <p> If the underlying class is an array class:
1393 * <ul>
1394 * <li> its {@code PUBLIC}, {@code PRIVATE} and {@code PROTECTED}
1395 * access flags are the same as those of its component type
1396 * <li> its {@code ABSTRACT} and {@code FINAL} flags are present
1397 * <li> its {@code INTERFACE} flag is absent, even when the
1398 * component type is an interface
1399 * </ul>
1400 * If this {@code Class} object represents a primitive type or
1401 * void, the flags are {@code PUBLIC}, {@code ABSTRACT}, and
1402 * {@code FINAL}.
1403 * For {@code Class} objects representing void, primitive types, and
1404 * arrays, access flags are absent other than as specified above.
1405 *
1406 * @see #getModifiers()
1407 * @jvms 4.1 The ClassFile Structure
1408 * @jvms 4.7.6 The InnerClasses Attribute
1409 * @since 20
1410 */
1411 public Set<AccessFlag> accessFlags() {
1412 // Location.CLASS allows SUPER and AccessFlag.MODULE which
1413 // INNER_CLASS forbids. INNER_CLASS allows PRIVATE, PROTECTED,
1414 // and STATIC, which are not allowed on Location.CLASS.
1415 // Use getClassFileAccessFlags to expose SUPER status.
1416 var location = (isMemberClass() || isLocalClass() ||
1417 isAnonymousClass() || isArray()) ?
1418 AccessFlag.Location.INNER_CLASS :
1419 AccessFlag.Location.CLASS;
1420 return getReflectionFactory().parseAccessFlags((location == AccessFlag.Location.CLASS) ?
1421 getClassFileAccessFlags() : getModifiers(), location, this);
1422 }
1423
1424 /**
1425 * Gets the signers of this class.
1426 *
1427 * @return the signers of this class, or null if there are no signers. In
1428 * particular, this method returns null if this {@code Class} object represents
1429 * a primitive type or void.
1430 * @since 1.1
1431 */
1432 public Object[] getSigners() {
1433 var signers = this.signers;
1434 return signers == null ? null : signers.clone();
1435 }
1436
1437 /**
1438 * Set the signers of this class.
1439 */
1440 void setSigners(Object[] signers) {
1441 if (!isPrimitive() && !isArray()) {
1442 this.signers = signers;
1443 }
1444 }
1445
1446 /**
1447 * If this {@code Class} object represents a local or anonymous
1448 * class within a method, returns a {@link
1449 * java.lang.reflect.Method Method} object representing the
1450 * immediately enclosing method of the underlying class. Returns
1451 * {@code null} otherwise.
1452 *
1453 * In particular, this method returns {@code null} if the underlying
1454 * class is a local or anonymous class immediately enclosed by a class or
1455 * interface declaration, instance initializer or static initializer.
1456 *
1457 * @return the immediately enclosing method of the underlying class, if
1458 * that class is a local or anonymous class; otherwise {@code null}.
1459 *
1460 * @since 1.5
1461 */
1462 public Method getEnclosingMethod() {
1463 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1464
1465 if (enclosingInfo == null)
1466 return null;
1467 else {
1468 if (!enclosingInfo.isMethod())
1469 return null;
1470
1471 MethodRepository typeInfo = MethodRepository.make(enclosingInfo.getDescriptor(),
1472 getFactory());
1473 Class<?> returnType = toClass(typeInfo.getReturnType());
1474 Type [] parameterTypes = typeInfo.getParameterTypes();
1475 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length];
1476
1477 // Convert Types to Classes; returned types *should*
1478 // be class objects since the methodDescriptor's used
1479 // don't have generics information
1480 for(int i = 0; i < parameterClasses.length; i++)
1481 parameterClasses[i] = toClass(parameterTypes[i]);
1482
1483 final Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass();
1484 Method[] candidates = enclosingCandidate.privateGetDeclaredMethods(false);
1485
1486 /*
1487 * Loop over all declared methods; match method name,
1488 * number of and type of parameters, *and* return
1489 * type. Matching return type is also necessary
1490 * because of covariant returns, etc.
1491 */
1492 ReflectionFactory fact = getReflectionFactory();
1493 for (Method m : candidates) {
1494 if (m.getName().equals(enclosingInfo.getName()) &&
1495 arrayContentsEq(parameterClasses,
1496 fact.getExecutableSharedParameterTypes(m))) {
1497 // finally, check return type
1498 if (m.getReturnType().equals(returnType)) {
1499 return fact.copyMethod(m);
1500 }
1501 }
1502 }
1503
1504 throw new InternalError("Enclosing method not found");
1505 }
1506 }
1507
1508 private native Object[] getEnclosingMethod0();
1509
1510 private EnclosingMethodInfo getEnclosingMethodInfo() {
1511 Object[] enclosingInfo = getEnclosingMethod0();
1512 if (enclosingInfo == null)
1513 return null;
1514 else {
1515 return new EnclosingMethodInfo(enclosingInfo);
1516 }
1517 }
1518
1519 private static final class EnclosingMethodInfo {
1520 private final Class<?> enclosingClass;
1521 private final String name;
1522 private final String descriptor;
1523
1524 static void validate(Object[] enclosingInfo) {
1525 if (enclosingInfo.length != 3)
1526 throw new InternalError("Malformed enclosing method information");
1527 try {
1528 // The array is expected to have three elements:
1529
1530 // the immediately enclosing class
1531 Class<?> enclosingClass = (Class<?>)enclosingInfo[0];
1532 assert(enclosingClass != null);
1533
1534 // the immediately enclosing method or constructor's
1535 // name (can be null).
1536 String name = (String)enclosingInfo[1];
1537
1538 // the immediately enclosing method or constructor's
1539 // descriptor (null iff name is).
1540 String descriptor = (String)enclosingInfo[2];
1541 assert((name != null && descriptor != null) || name == descriptor);
1542 } catch (ClassCastException cce) {
1543 throw new InternalError("Invalid type in enclosing method information", cce);
1544 }
1545 }
1546
1547 EnclosingMethodInfo(Object[] enclosingInfo) {
1548 validate(enclosingInfo);
1549 this.enclosingClass = (Class<?>)enclosingInfo[0];
1550 this.name = (String)enclosingInfo[1];
1551 this.descriptor = (String)enclosingInfo[2];
1552 }
1553
1554 boolean isPartial() {
1555 return enclosingClass == null || name == null || descriptor == null;
1556 }
1557
1558 boolean isConstructor() { return !isPartial() && ConstantDescs.INIT_NAME.equals(name); }
1559
1560 boolean isMethod() { return !isPartial() && !isConstructor() && !ConstantDescs.CLASS_INIT_NAME.equals(name); }
1561
1562 Class<?> getEnclosingClass() { return enclosingClass; }
1563
1564 String getName() { return name; }
1565
1566 String getDescriptor() { return descriptor; }
1567
1568 }
1569
1570 private static Class<?> toClass(Type o) {
1571 if (o instanceof GenericArrayType gat)
1572 return toClass(gat.getGenericComponentType()).arrayType();
1573 return (Class<?>)o;
1574 }
1575
1576 /**
1577 * If this {@code Class} object represents a local or anonymous
1578 * class within a constructor, returns a {@link
1579 * java.lang.reflect.Constructor Constructor} object representing
1580 * the immediately enclosing constructor of the underlying
1581 * class. Returns {@code null} otherwise. In particular, this
1582 * method returns {@code null} if the underlying class is a local
1583 * or anonymous class immediately enclosed by a class or
1584 * interface declaration, instance initializer or static initializer.
1585 *
1586 * @return the immediately enclosing constructor of the underlying class, if
1587 * that class is a local or anonymous class; otherwise {@code null}.
1588 *
1589 * @since 1.5
1590 */
1591 public Constructor<?> getEnclosingConstructor() {
1592 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1593
1594 if (enclosingInfo == null)
1595 return null;
1596 else {
1597 if (!enclosingInfo.isConstructor())
1598 return null;
1599
1600 ConstructorRepository typeInfo = ConstructorRepository.make(enclosingInfo.getDescriptor(),
1601 getFactory());
1602 Type [] parameterTypes = typeInfo.getParameterTypes();
1603 Class<?>[] parameterClasses = new Class<?>[parameterTypes.length];
1604
1605 // Convert Types to Classes; returned types *should*
1606 // be class objects since the methodDescriptor's used
1607 // don't have generics information
1608 for (int i = 0; i < parameterClasses.length; i++)
1609 parameterClasses[i] = toClass(parameterTypes[i]);
1610
1611
1612 final Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass();
1613 Constructor<?>[] candidates = enclosingCandidate
1614 .privateGetDeclaredConstructors(false);
1615 /*
1616 * Loop over all declared constructors; match number
1617 * of and type of parameters.
1618 */
1619 ReflectionFactory fact = getReflectionFactory();
1620 for (Constructor<?> c : candidates) {
1621 if (arrayContentsEq(parameterClasses,
1622 fact.getExecutableSharedParameterTypes(c))) {
1623 return fact.copyConstructor(c);
1624 }
1625 }
1626
1627 throw new InternalError("Enclosing constructor not found");
1628 }
1629 }
1630
1631
1632 /**
1633 * If the class or interface represented by this {@code Class} object
1634 * is a member of another class, returns the {@code Class} object
1635 * representing the class in which it was declared. This method returns
1636 * null if this class or interface is not a member of any other class. If
1637 * this {@code Class} object represents an array class, a primitive
1638 * type, or void, then this method returns null.
1639 *
1640 * @return the declaring class for this class
1641 * @since 1.1
1642 */
1643 public Class<?> getDeclaringClass() {
1644 return getDeclaringClass0();
1645 }
1646
1647 private native Class<?> getDeclaringClass0();
1648
1649
1650 /**
1651 * Returns the immediately enclosing class of the underlying
1652 * class. If the underlying class is a top level class this
1653 * method returns {@code null}.
1654 * @return the immediately enclosing class of the underlying class
1655 * @since 1.5
1656 */
1657 public Class<?> getEnclosingClass() {
1658 // There are five kinds of classes (or interfaces):
1659 // a) Top level classes
1660 // b) Nested classes (static member classes)
1661 // c) Inner classes (non-static member classes)
1662 // d) Local classes (named classes declared within a method)
1663 // e) Anonymous classes
1664
1665
1666 // JVM Spec 4.7.7: A class must have an EnclosingMethod
1667 // attribute if and only if it is a local class or an
1668 // anonymous class.
1669 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1670 Class<?> enclosingCandidate;
1671
1672 if (enclosingInfo == null) {
1673 // This is a top level or a nested class or an inner class (a, b, or c)
1674 enclosingCandidate = getDeclaringClass0();
1675 } else {
1676 Class<?> enclosingClass = enclosingInfo.getEnclosingClass();
1677 // This is a local class or an anonymous class (d or e)
1678 if (enclosingClass == this || enclosingClass == null)
1679 throw new InternalError("Malformed enclosing method information");
1680 else
1681 enclosingCandidate = enclosingClass;
1682 }
1683 return enclosingCandidate;
1684 }
1685
1686 /**
1687 * Returns the simple name of the underlying class as given in the
1688 * source code. An empty string is returned if the underlying class is
1689 * {@linkplain #isAnonymousClass() anonymous}.
1690 * A {@linkplain #isSynthetic() synthetic class}, one not present
1691 * in source code, can have a non-empty name including special
1692 * characters, such as "{@code $}".
1693 *
1694 * <p>The simple name of an {@linkplain #isArray() array class} is the simple name of the
1695 * component type with "[]" appended. In particular the simple
1696 * name of an array class whose component type is anonymous is "[]".
1697 *
1698 * @return the simple name of the underlying class
1699 * @since 1.5
1700 */
1701 public String getSimpleName() {
1702 ReflectionData<T> rd = reflectionData();
1703 String simpleName = rd.simpleName;
1704 if (simpleName == null) {
1705 rd.simpleName = simpleName = getSimpleName0();
1706 }
1707 return simpleName;
1708 }
1709
1710 private String getSimpleName0() {
1711 if (isArray()) {
1712 return getComponentType().getSimpleName().concat("[]");
1713 }
1714 String simpleName = getSimpleBinaryName();
1715 if (simpleName == null) { // top level class
1716 simpleName = getName();
1717 simpleName = simpleName.substring(simpleName.lastIndexOf('.') + 1); // strip the package name
1718 }
1719 return simpleName;
1720 }
1721
1722 /**
1723 * Return an informative string for the name of this class or interface.
1724 *
1725 * @return an informative string for the name of this class or interface
1726 * @since 1.8
1727 */
1728 public String getTypeName() {
1729 if (isArray()) {
1730 try {
1731 Class<?> cl = this;
1732 int dimensions = 0;
1733 do {
1734 dimensions++;
1735 cl = cl.getComponentType();
1736 } while (cl.isArray());
1737 return cl.getName().concat("[]".repeat(dimensions));
1738 } catch (Throwable e) { /*FALLTHRU*/ }
1739 }
1740 return getName();
1741 }
1742
1743 /**
1744 * Returns the canonical name of the underlying class as
1745 * defined by <cite>The Java Language Specification</cite>.
1746 * Returns {@code null} if the underlying class does not have a canonical
1747 * name. Classes without canonical names include:
1748 * <ul>
1749 * <li>a {@linkplain #isLocalClass() local class}
1750 * <li>a {@linkplain #isAnonymousClass() anonymous class}
1751 * <li>a {@linkplain #isHidden() hidden class}
1752 * <li>an array whose component type does not have a canonical name</li>
1753 * </ul>
1754 *
1755 * The canonical name for a primitive class is the keyword for the
1756 * corresponding primitive type ({@code byte}, {@code short},
1757 * {@code char}, {@code int}, and so on).
1758 *
1759 * <p>An array type has a canonical name if and only if its
1760 * component type has a canonical name. When an array type has a
1761 * canonical name, it is equal to the canonical name of the
1762 * component type followed by "{@code []}".
1763 *
1764 * @return the canonical name of the underlying class if it exists, and
1765 * {@code null} otherwise.
1766 * @jls 6.7 Fully Qualified Names and Canonical Names
1767 * @since 1.5
1768 */
1769 public String getCanonicalName() {
1770 ReflectionData<T> rd = reflectionData();
1771 String canonicalName = rd.canonicalName;
1772 if (canonicalName == null) {
1773 rd.canonicalName = canonicalName = getCanonicalName0();
1774 }
1775 return canonicalName == ReflectionData.NULL_SENTINEL? null : canonicalName;
1776 }
1777
1778 private String getCanonicalName0() {
1779 if (isArray()) {
1780 String canonicalName = getComponentType().getCanonicalName();
1781 if (canonicalName != null)
1782 return canonicalName.concat("[]");
1783 else
1784 return ReflectionData.NULL_SENTINEL;
1785 }
1786 if (isHidden() || isLocalOrAnonymousClass())
1787 return ReflectionData.NULL_SENTINEL;
1788 Class<?> enclosingClass = getEnclosingClass();
1789 if (enclosingClass == null) { // top level class
1790 return getName();
1791 } else {
1792 String enclosingName = enclosingClass.getCanonicalName();
1793 if (enclosingName == null)
1794 return ReflectionData.NULL_SENTINEL;
1795 String simpleName = getSimpleName();
1796 return new StringBuilder(enclosingName.length() + simpleName.length() + 1)
1797 .append(enclosingName)
1798 .append('.')
1799 .append(simpleName)
1800 .toString();
1801 }
1802 }
1803
1804 /**
1805 * Returns {@code true} if and only if the underlying class
1806 * is an anonymous class.
1807 *
1808 * @apiNote
1809 * An anonymous class is not a {@linkplain #isHidden() hidden class}.
1810 *
1811 * @return {@code true} if and only if this class is an anonymous class.
1812 * @since 1.5
1813 * @jls 15.9.5 Anonymous Class Declarations
1814 */
1815 public boolean isAnonymousClass() {
1816 return !isArray() && isLocalOrAnonymousClass() &&
1817 getSimpleBinaryName0() == null;
1818 }
1819
1820 /**
1821 * Returns {@code true} if and only if the underlying class
1822 * is a local class.
1823 *
1824 * @return {@code true} if and only if this class is a local class.
1825 * @since 1.5
1826 * @jls 14.3 Local Class and Interface Declarations
1827 */
1828 public boolean isLocalClass() {
1829 return isLocalOrAnonymousClass() &&
1830 (isArray() || getSimpleBinaryName0() != null);
1831 }
1832
1833 /**
1834 * Returns {@code true} if and only if the underlying class
1835 * is a member class.
1836 *
1837 * @return {@code true} if and only if this class is a member class.
1838 * @since 1.5
1839 * @jls 8.5 Member Class and Interface Declarations
1840 */
1841 public boolean isMemberClass() {
1842 return !isLocalOrAnonymousClass() && getDeclaringClass0() != null;
1843 }
1844
1845 /**
1846 * Returns the "simple binary name" of the underlying class, i.e.,
1847 * the binary name without the leading enclosing class name.
1848 * Returns {@code null} if the underlying class is a top level
1849 * class.
1850 */
1851 private String getSimpleBinaryName() {
1852 if (isTopLevelClass())
1853 return null;
1854 String name = getSimpleBinaryName0();
1855 if (name == null) // anonymous class
1856 return "";
1857 return name;
1858 }
1859
1860 private native String getSimpleBinaryName0();
1861
1862 /**
1863 * Returns {@code true} if this is a top level class. Returns {@code false}
1864 * otherwise.
1865 */
1866 private boolean isTopLevelClass() {
1867 return !isLocalOrAnonymousClass() && getDeclaringClass0() == null;
1868 }
1869
1870 /**
1871 * Returns {@code true} if this is a local class or an anonymous
1872 * class. Returns {@code false} otherwise.
1873 */
1874 private boolean isLocalOrAnonymousClass() {
1875 // JVM Spec 4.7.7: A class must have an EnclosingMethod
1876 // attribute if and only if it is a local class or an
1877 // anonymous class.
1878 return hasEnclosingMethodInfo();
1879 }
1880
1881 private boolean hasEnclosingMethodInfo() {
1882 Object[] enclosingInfo = getEnclosingMethod0();
1883 if (enclosingInfo != null) {
1884 EnclosingMethodInfo.validate(enclosingInfo);
1885 return true;
1886 }
1887 return false;
1888 }
1889
1890 /**
1891 * Returns an array containing {@code Class} objects representing all
1892 * the public classes and interfaces that are members of the class
1893 * represented by this {@code Class} object. This includes public
1894 * class and interface members inherited from superclasses and public class
1895 * and interface members declared by the class. This method returns an
1896 * array of length 0 if this {@code Class} object has no public member
1897 * classes or interfaces. This method also returns an array of length 0 if
1898 * this {@code Class} object represents a primitive type, an array
1899 * class, or void.
1900 *
1901 * @return the array of {@code Class} objects representing the public
1902 * members of this class
1903 * @since 1.1
1904 */
1905 public Class<?>[] getClasses() {
1906 List<Class<?>> list = new ArrayList<>();
1907 Class<?> currentClass = Class.this;
1908 while (currentClass != null) {
1909 for (Class<?> m : currentClass.getDeclaredClasses()) {
1910 if (Modifier.isPublic(m.getModifiers())) {
1911 list.add(m);
1912 }
1913 }
1914 currentClass = currentClass.getSuperclass();
1915 }
1916 return list.toArray(new Class<?>[0]);
1917 }
1918
1919
1920 /**
1921 * Returns an array containing {@code Field} objects reflecting all
1922 * the accessible public fields of the class or interface represented by
1923 * this {@code Class} object.
1924 *
1925 * <p> If this {@code Class} object represents a class or interface with
1926 * no accessible public fields, then this method returns an array of length
1927 * 0.
1928 *
1929 * <p> If this {@code Class} object represents a class, then this method
1930 * returns the public fields of the class and of all its superclasses and
1931 * superinterfaces.
1932 *
1933 * <p> If this {@code Class} object represents an interface, then this
1934 * method returns the fields of the interface and of all its
1935 * superinterfaces.
1936 *
1937 * <p> If this {@code Class} object represents an array type, a primitive
1938 * type, or void, then this method returns an array of length 0.
1939 *
1940 * <p> The elements in the returned array are not sorted and are not in any
1941 * particular order.
1942 *
1943 * @return the array of {@code Field} objects representing the
1944 * public fields
1945 *
1946 * @since 1.1
1947 * @jls 8.2 Class Members
1948 * @jls 8.3 Field Declarations
1949 */
1950 public Field[] getFields() {
1951 return copyFields(privateGetPublicFields());
1952 }
1953
1954
1955 /**
1956 * Returns an array containing {@code Method} objects reflecting all the
1957 * public methods of the class or interface represented by this {@code
1958 * Class} object, including those declared by the class or interface and
1959 * those inherited from superclasses and superinterfaces.
1960 *
1961 * <p> If this {@code Class} object represents an array type, then the
1962 * returned array has a {@code Method} object for each of the public
1963 * methods inherited by the array type from {@code Object}. It does not
1964 * contain a {@code Method} object for {@code clone()}.
1965 *
1966 * <p> If this {@code Class} object represents an interface then the
1967 * returned array does not contain any implicitly declared methods from
1968 * {@code Object}. Therefore, if no methods are explicitly declared in
1969 * this interface or any of its superinterfaces then the returned array
1970 * has length 0. (Note that a {@code Class} object which represents a class
1971 * always has public methods, inherited from {@code Object}.)
1972 *
1973 * <p> The returned array never contains methods with names {@value
1974 * ConstantDescs#INIT_NAME} or {@value ConstantDescs#CLASS_INIT_NAME}.
1975 *
1976 * <p> The elements in the returned array are not sorted and are not in any
1977 * particular order.
1978 *
1979 * <p> Generally, the result is computed as with the following 4 step algorithm.
1980 * Let C be the class or interface represented by this {@code Class} object:
1981 * <ol>
1982 * <li> A union of methods is composed of:
1983 * <ol type="a">
1984 * <li> C's declared public instance and static methods as returned by
1985 * {@link #getDeclaredMethods()} and filtered to include only public
1986 * methods.</li>
1987 * <li> If C is a class other than {@code Object}, then include the result
1988 * of invoking this algorithm recursively on the superclass of C.</li>
1989 * <li> Include the results of invoking this algorithm recursively on all
1990 * direct superinterfaces of C, but include only instance methods.</li>
1991 * </ol></li>
1992 * <li> Union from step 1 is partitioned into subsets of methods with same
1993 * signature (name, parameter types) and return type.</li>
1994 * <li> Within each such subset only the most specific methods are selected.
1995 * Let method M be a method from a set of methods with same signature
1996 * and return type. M is most specific if there is no such method
1997 * N != M from the same set, such that N is more specific than M.
1998 * N is more specific than M if:
1999 * <ol type="a">
2000 * <li> N is declared by a class and M is declared by an interface; or</li>
2001 * <li> N and M are both declared by classes or both by interfaces and
2002 * N's declaring type is the same as or a subtype of M's declaring type
2003 * (clearly, if M's and N's declaring types are the same type, then
2004 * M and N are the same method).</li>
2005 * </ol></li>
2006 * <li> The result of this algorithm is the union of all selected methods from
2007 * step 3.</li>
2008 * </ol>
2009 *
2010 * @apiNote There may be more than one method with a particular name
2011 * and parameter types in a class because while the Java language forbids a
2012 * class to declare multiple methods with the same signature but different
2013 * return types, the Java virtual machine does not. This
2014 * increased flexibility in the virtual machine can be used to
2015 * implement various language features. For example, covariant
2016 * returns can be implemented with {@linkplain
2017 * java.lang.reflect.Method#isBridge bridge methods}; the bridge
2018 * method and the overriding method would have the same
2019 * signature but different return types.
2020 *
2021 * @return the array of {@code Method} objects representing the
2022 * public methods of this class
2023 *
2024 * @jls 8.2 Class Members
2025 * @jls 8.4 Method Declarations
2026 * @since 1.1
2027 */
2028 public Method[] getMethods() {
2029 return copyMethods(privateGetPublicMethods());
2030 }
2031
2032
2033 /**
2034 * Returns an array containing {@code Constructor} objects reflecting
2035 * all the public constructors of the class represented by this
2036 * {@code Class} object. An array of length 0 is returned if the
2037 * class has no public constructors, or if the class is an array class, or
2038 * if the class reflects a primitive type or void.
2039 *
2040 * @apiNote
2041 * While this method returns an array of {@code
2042 * Constructor<T>} objects (that is an array of constructors from
2043 * this class), the return type of this method is {@code
2044 * Constructor<?>[]} and <em>not</em> {@code Constructor<T>[]} as
2045 * might be expected. This less informative return type is
2046 * necessary since after being returned from this method, the
2047 * array could be modified to hold {@code Constructor} objects for
2048 * different classes, which would violate the type guarantees of
2049 * {@code Constructor<T>[]}.
2050 *
2051 * @return the array of {@code Constructor} objects representing the
2052 * public constructors of this class
2053 *
2054 * @see #getDeclaredConstructors()
2055 * @since 1.1
2056 */
2057 public Constructor<?>[] getConstructors() {
2058 return copyConstructors(privateGetDeclaredConstructors(true));
2059 }
2060
2061
2062 /**
2063 * Returns a {@code Field} object that reflects the specified public member
2064 * field of the class or interface represented by this {@code Class}
2065 * object. The {@code name} parameter is a {@code String} specifying the
2066 * simple name of the desired field.
2067 *
2068 * <p> The field to be reflected is determined by the algorithm that
2069 * follows. Let C be the class or interface represented by this {@code Class} object:
2070 *
2071 * <OL>
2072 * <LI> If C declares a public field with the name specified, that is the
2073 * field to be reflected.</LI>
2074 * <LI> If no field was found in step 1 above, this algorithm is applied
2075 * recursively to each direct superinterface of C. The direct
2076 * superinterfaces are searched in the order they were declared.</LI>
2077 * <LI> If no field was found in steps 1 and 2 above, and C has a
2078 * superclass S, then this algorithm is invoked recursively upon S.
2079 * If C has no superclass, then a {@code NoSuchFieldException}
2080 * is thrown.</LI>
2081 * </OL>
2082 *
2083 * <p> If this {@code Class} object represents an array type, then this
2084 * method does not find the {@code length} field of the array type.
2085 *
2086 * @param name the field name
2087 * @return the {@code Field} object of this class specified by
2088 * {@code name}
2089 * @throws NoSuchFieldException if a field with the specified name is
2090 * not found.
2091 * @throws NullPointerException if {@code name} is {@code null}
2092 *
2093 * @since 1.1
2094 * @jls 8.2 Class Members
2095 * @jls 8.3 Field Declarations
2096 */
2097 public Field getField(String name) throws NoSuchFieldException {
2098 Objects.requireNonNull(name);
2099 Field field = getField0(name);
2100 if (field == null) {
2101 throw new NoSuchFieldException(name);
2102 }
2103 return getReflectionFactory().copyField(field);
2104 }
2105
2106
2107 /**
2108 * Returns a {@code Method} object that reflects the specified public
2109 * member method of the class or interface represented by this
2110 * {@code Class} object. The {@code name} parameter is a
2111 * {@code String} specifying the simple name of the desired method. The
2112 * {@code parameterTypes} parameter is an array of {@code Class}
2113 * objects that identify the method's formal parameter types, in declared
2114 * order. If {@code parameterTypes} is {@code null}, it is
2115 * treated as if it were an empty array.
2116 *
2117 * <p> If this {@code Class} object represents an array type, then this
2118 * method finds any public method inherited by the array type from
2119 * {@code Object} except method {@code clone()}.
2120 *
2121 * <p> If this {@code Class} object represents an interface then this
2122 * method does not find any implicitly declared method from
2123 * {@code Object}. Therefore, if no methods are explicitly declared in
2124 * this interface or any of its superinterfaces, then this method does not
2125 * find any method.
2126 *
2127 * <p> This method does not find any method with name {@value
2128 * ConstantDescs#INIT_NAME} or {@value ConstantDescs#CLASS_INIT_NAME}.
2129 *
2130 * <p> Generally, the method to be reflected is determined by the 4 step
2131 * algorithm that follows.
2132 * Let C be the class or interface represented by this {@code Class} object:
2133 * <ol>
2134 * <li> A union of methods is composed of:
2135 * <ol type="a">
2136 * <li> C's declared public instance and static methods as returned by
2137 * {@link #getDeclaredMethods()} and filtered to include only public
2138 * methods that match given {@code name} and {@code parameterTypes}</li>
2139 * <li> If C is a class other than {@code Object}, then include the result
2140 * of invoking this algorithm recursively on the superclass of C.</li>
2141 * <li> Include the results of invoking this algorithm recursively on all
2142 * direct superinterfaces of C, but include only instance methods.</li>
2143 * </ol></li>
2144 * <li> This union is partitioned into subsets of methods with same
2145 * return type (the selection of methods from step 1 also guarantees that
2146 * they have the same method name and parameter types).</li>
2147 * <li> Within each such subset only the most specific methods are selected.
2148 * Let method M be a method from a set of methods with same VM
2149 * signature (return type, name, parameter types).
2150 * M is most specific if there is no such method N != M from the same
2151 * set, such that N is more specific than M. N is more specific than M
2152 * if:
2153 * <ol type="a">
2154 * <li> N is declared by a class and M is declared by an interface; or</li>
2155 * <li> N and M are both declared by classes or both by interfaces and
2156 * N's declaring type is the same as or a subtype of M's declaring type
2157 * (clearly, if M's and N's declaring types are the same type, then
2158 * M and N are the same method).</li>
2159 * </ol></li>
2160 * <li> The result of this algorithm is chosen arbitrarily from the methods
2161 * with most specific return type among all selected methods from step 3.
2162 * Let R be a return type of a method M from the set of all selected methods
2163 * from step 3. M is a method with most specific return type if there is
2164 * no such method N != M from the same set, having return type S != R,
2165 * such that S is a subtype of R as determined by
2166 * R.class.{@link #isAssignableFrom}(S.class).
2167 * </ol>
2168 *
2169 * @apiNote There may be more than one method with matching name and
2170 * parameter types in a class because while the Java language forbids a
2171 * class to declare multiple methods with the same signature but different
2172 * return types, the Java virtual machine does not. This
2173 * increased flexibility in the virtual machine can be used to
2174 * implement various language features. For example, covariant
2175 * returns can be implemented with {@linkplain
2176 * java.lang.reflect.Method#isBridge bridge methods}; the bridge
2177 * method and the overriding method would have the same
2178 * signature but different return types. This method would return the
2179 * overriding method as it would have a more specific return type.
2180 *
2181 * @param name the name of the method
2182 * @param parameterTypes the list of parameters
2183 * @return the {@code Method} object that matches the specified
2184 * {@code name} and {@code parameterTypes}
2185 * @throws NoSuchMethodException if a matching method is not found
2186 * or if the name is {@value ConstantDescs#INIT_NAME} or
2187 * {@value ConstantDescs#CLASS_INIT_NAME}.
2188 * @throws NullPointerException if {@code name} is {@code null}
2189 *
2190 * @jls 8.2 Class Members
2191 * @jls 8.4 Method Declarations
2192 * @since 1.1
2193 */
2194 public Method getMethod(String name, Class<?>... parameterTypes)
2195 throws NoSuchMethodException {
2196 Objects.requireNonNull(name);
2197 Method method = getMethod0(name, parameterTypes);
2198 if (method == null) {
2199 throw new NoSuchMethodException(methodToString(name, parameterTypes));
2200 }
2201 return getReflectionFactory().copyMethod(method);
2202 }
2203
2204 /**
2205 * Returns a {@code Constructor} object that reflects the specified
2206 * public constructor of the class represented by this {@code Class}
2207 * object. The {@code parameterTypes} parameter is an array of
2208 * {@code Class} objects that identify the constructor's formal
2209 * parameter types, in declared order.
2210 *
2211 * If this {@code Class} object represents an inner class
2212 * declared in a non-static context, the formal parameter types
2213 * include the explicit enclosing instance as the first parameter.
2214 *
2215 * <p> The constructor to reflect is the public constructor of the class
2216 * represented by this {@code Class} object whose formal parameter
2217 * types match those specified by {@code parameterTypes}.
2218 *
2219 * @param parameterTypes the parameter array
2220 * @return the {@code Constructor} object of the public constructor that
2221 * matches the specified {@code parameterTypes}
2222 * @throws NoSuchMethodException if a matching constructor is not found,
2223 * including when this {@code Class} object represents
2224 * an interface, a primitive type, an array class, or void.
2225 *
2226 * @see #getDeclaredConstructor(Class[])
2227 * @since 1.1
2228 */
2229 public Constructor<T> getConstructor(Class<?>... parameterTypes)
2230 throws NoSuchMethodException {
2231 return getReflectionFactory().copyConstructor(
2232 getConstructor0(parameterTypes, Member.PUBLIC));
2233 }
2234
2235
2236 /**
2237 * Returns an array of {@code Class} objects reflecting all the
2238 * classes and interfaces declared as members of the class represented by
2239 * this {@code Class} object. This includes public, protected, default
2240 * (package) access, and private classes and interfaces declared by the
2241 * class, but excludes inherited classes and interfaces. This method
2242 * returns an array of length 0 if the class declares no classes or
2243 * interfaces as members, or if this {@code Class} object represents a
2244 * primitive type, an array class, or void.
2245 *
2246 * @return the array of {@code Class} objects representing all the
2247 * declared members of this class
2248 *
2249 * @since 1.1
2250 * @jls 8.5 Member Class and Interface Declarations
2251 */
2252 public Class<?>[] getDeclaredClasses() {
2253 return getDeclaredClasses0();
2254 }
2255
2256
2257 /**
2258 * Returns an array of {@code Field} objects reflecting all the fields
2259 * declared by the class or interface represented by this
2260 * {@code Class} object. This includes public, protected, default
2261 * (package) access, and private fields, but excludes inherited fields.
2262 *
2263 * <p> If this {@code Class} object represents a class or interface with no
2264 * declared fields, then this method returns an array of length 0.
2265 *
2266 * <p> If this {@code Class} object represents an array type, a primitive
2267 * type, or void, then this method returns an array of length 0.
2268 *
2269 * <p> The elements in the returned array are not sorted and are not in any
2270 * particular order.
2271 *
2272 * @return the array of {@code Field} objects representing all the
2273 * declared fields of this class
2274 *
2275 * @since 1.1
2276 * @jls 8.2 Class Members
2277 * @jls 8.3 Field Declarations
2278 */
2279 public Field[] getDeclaredFields() {
2280 return copyFields(privateGetDeclaredFields(false));
2281 }
2282
2283 /**
2284 * Returns an array of {@code RecordComponent} objects representing all the
2285 * record components of this record class, or {@code null} if this class is
2286 * not a record class.
2287 *
2288 * <p> The components are returned in the same order that they are declared
2289 * in the record header. The array is empty if this record class has no
2290 * components. If the class is not a record class, that is {@link
2291 * #isRecord()} returns {@code false}, then this method returns {@code null}.
2292 * Conversely, if {@link #isRecord()} returns {@code true}, then this method
2293 * returns a non-null value.
2294 *
2295 * @apiNote
2296 * <p> The following method can be used to find the record canonical constructor:
2297 *
2298 * {@snippet lang="java" :
2299 * static <T extends Record> Constructor<T> getCanonicalConstructor(Class<T> cls)
2300 * throws NoSuchMethodException {
2301 * Class<?>[] paramTypes =
2302 * Arrays.stream(cls.getRecordComponents())
2303 * .map(RecordComponent::getType)
2304 * .toArray(Class<?>[]::new);
2305 * return cls.getDeclaredConstructor(paramTypes);
2306 * }}
2307 *
2308 * @return An array of {@code RecordComponent} objects representing all the
2309 * record components of this record class, or {@code null} if this
2310 * class is not a record class
2311 *
2312 * @jls 8.10 Record Classes
2313 * @since 16
2314 */
2315 public RecordComponent[] getRecordComponents() {
2316 if (!isRecord()) {
2317 return null;
2318 }
2319 return getRecordComponents0();
2320 }
2321
2322 /**
2323 * Returns an array containing {@code Method} objects reflecting all the
2324 * declared methods of the class or interface represented by this {@code
2325 * Class} object, including public, protected, default (package)
2326 * access, and private methods, but excluding inherited methods.
2327 * The declared methods may include methods <em>not</em> in the
2328 * source of the class or interface, including {@linkplain
2329 * Method#isBridge bridge methods} and other {@linkplain
2330 * Executable#isSynthetic synthetic} methods added by compilers.
2331 *
2332 * <p> If this {@code Class} object represents a class or interface that
2333 * has multiple declared methods with the same name and parameter types,
2334 * but different return types, then the returned array has a {@code Method}
2335 * object for each such method.
2336 *
2337 * <p> If this {@code Class} object represents a class or interface that
2338 * has a class initialization method {@value ConstantDescs#CLASS_INIT_NAME},
2339 * then the returned array does <em>not</em> have a corresponding {@code
2340 * Method} object.
2341 *
2342 * <p> If this {@code Class} object represents a class or interface with no
2343 * declared methods, then the returned array has length 0.
2344 *
2345 * <p> If this {@code Class} object represents an array type, a primitive
2346 * type, or void, then the returned array has length 0.
2347 *
2348 * <p> The elements in the returned array are not sorted and are not in any
2349 * particular order.
2350 *
2351 * @return the array of {@code Method} objects representing all the
2352 * declared methods of this class
2353 *
2354 * @jls 8.2 Class Members
2355 * @jls 8.4 Method Declarations
2356 * @see <a
2357 * href="{@docRoot}/java.base/java/lang/reflect/package-summary.html#LanguageJvmModel">Java
2358 * programming language and JVM modeling in core reflection</a>
2359 * @since 1.1
2360 */
2361 public Method[] getDeclaredMethods() {
2362 return copyMethods(privateGetDeclaredMethods(false));
2363 }
2364
2365 /**
2366 * Returns an array of {@code Constructor} objects reflecting all the
2367 * constructors implicitly or explicitly declared by the class represented by this
2368 * {@code Class} object. These are public, protected, default
2369 * (package) access, and private constructors. The elements in the array
2370 * returned are not sorted and are not in any particular order. If the
2371 * class has a default constructor (JLS {@jls 8.8.9}), it is included in the returned array.
2372 * If a record class has a canonical constructor (JLS {@jls
2373 * 8.10.4.1}, {@jls 8.10.4.2}), it is included in the returned array.
2374 *
2375 * This method returns an array of length 0 if this {@code Class}
2376 * object represents an interface, a primitive type, an array class, or
2377 * void.
2378 *
2379 * @return the array of {@code Constructor} objects representing all the
2380 * declared constructors of this class
2381 *
2382 * @since 1.1
2383 * @see #getConstructors()
2384 * @jls 8.8 Constructor Declarations
2385 */
2386 public Constructor<?>[] getDeclaredConstructors() {
2387 return copyConstructors(privateGetDeclaredConstructors(false));
2388 }
2389
2390
2391 /**
2392 * Returns a {@code Field} object that reflects the specified declared
2393 * field of the class or interface represented by this {@code Class}
2394 * object. The {@code name} parameter is a {@code String} that specifies
2395 * the simple name of the desired field.
2396 *
2397 * <p> If this {@code Class} object represents an array type, then this
2398 * method does not find the {@code length} field of the array type.
2399 *
2400 * @param name the name of the field
2401 * @return the {@code Field} object for the specified field in this
2402 * class
2403 * @throws NoSuchFieldException if a field with the specified name is
2404 * not found.
2405 * @throws NullPointerException if {@code name} is {@code null}
2406 *
2407 * @since 1.1
2408 * @jls 8.2 Class Members
2409 * @jls 8.3 Field Declarations
2410 */
2411 public Field getDeclaredField(String name) throws NoSuchFieldException {
2412 Objects.requireNonNull(name);
2413 Field field = searchFields(privateGetDeclaredFields(false), name);
2414 if (field == null) {
2415 throw new NoSuchFieldException(name);
2416 }
2417 return getReflectionFactory().copyField(field);
2418 }
2419
2420
2421 /**
2422 * Returns a {@code Method} object that reflects the specified
2423 * declared method of the class or interface represented by this
2424 * {@code Class} object. The {@code name} parameter is a
2425 * {@code String} that specifies the simple name of the desired
2426 * method, and the {@code parameterTypes} parameter is an array of
2427 * {@code Class} objects that identify the method's formal parameter
2428 * types, in declared order. If more than one method with the same
2429 * parameter types is declared in a class, and one of these methods has a
2430 * return type that is more specific than any of the others, that method is
2431 * returned; otherwise one of the methods is chosen arbitrarily. If the
2432 * name is {@value ConstantDescs#INIT_NAME} or {@value
2433 * ConstantDescs#CLASS_INIT_NAME} a {@code NoSuchMethodException}
2434 * is raised.
2435 *
2436 * <p> If this {@code Class} object represents an array type, then this
2437 * method does not find the {@code clone()} method.
2438 *
2439 * @param name the name of the method
2440 * @param parameterTypes the parameter array
2441 * @return the {@code Method} object for the method of this class
2442 * matching the specified name and parameters
2443 * @throws NoSuchMethodException if a matching method is not found.
2444 * @throws NullPointerException if {@code name} is {@code null}
2445 *
2446 * @jls 8.2 Class Members
2447 * @jls 8.4 Method Declarations
2448 * @since 1.1
2449 */
2450 public Method getDeclaredMethod(String name, Class<?>... parameterTypes)
2451 throws NoSuchMethodException {
2452 Objects.requireNonNull(name);
2453 Method method = searchMethods(privateGetDeclaredMethods(false), name, parameterTypes);
2454 if (method == null) {
2455 throw new NoSuchMethodException(methodToString(name, parameterTypes));
2456 }
2457 return getReflectionFactory().copyMethod(method);
2458 }
2459
2460 /**
2461 * Returns the list of {@code Method} objects for the declared public
2462 * methods of this class or interface that have the specified method name
2463 * and parameter types.
2464 *
2465 * @param name the name of the method
2466 * @param parameterTypes the parameter array
2467 * @return the list of {@code Method} objects for the public methods of
2468 * this class matching the specified name and parameters
2469 */
2470 List<Method> getDeclaredPublicMethods(String name, Class<?>... parameterTypes) {
2471 Method[] methods = privateGetDeclaredMethods(/* publicOnly */ true);
2472 ReflectionFactory factory = getReflectionFactory();
2473 List<Method> result = new ArrayList<>();
2474 for (Method method : methods) {
2475 if (method.getName().equals(name)
2476 && Arrays.equals(
2477 factory.getExecutableSharedParameterTypes(method),
2478 parameterTypes)) {
2479 result.add(factory.copyMethod(method));
2480 }
2481 }
2482 return result;
2483 }
2484
2485 /**
2486 * Returns the most specific {@code Method} object of this class, super class or
2487 * interface that have the specified method name and parameter types.
2488 *
2489 * @param publicOnly true if only public methods are examined, otherwise all methods
2490 * @param name the name of the method
2491 * @param parameterTypes the parameter array
2492 * @return the {@code Method} object for the method found from this class matching
2493 * the specified name and parameters, or null if not found
2494 */
2495 Method findMethod(boolean publicOnly, String name, Class<?>... parameterTypes) {
2496 PublicMethods.MethodList res = getMethodsRecursive(name, parameterTypes, true, publicOnly);
2497 return res == null ? null : getReflectionFactory().copyMethod(res.getMostSpecific());
2498 }
2499
2500 /**
2501 * Returns a {@code Constructor} object that reflects the specified
2502 * constructor of the class represented by this
2503 * {@code Class} object. The {@code parameterTypes} parameter is
2504 * an array of {@code Class} objects that identify the constructor's
2505 * formal parameter types, in declared order.
2506 *
2507 * If this {@code Class} object represents an inner class
2508 * declared in a non-static context, the formal parameter types
2509 * include the explicit enclosing instance as the first parameter.
2510 *
2511 * @param parameterTypes the parameter array
2512 * @return The {@code Constructor} object for the constructor with the
2513 * specified parameter list
2514 * @throws NoSuchMethodException if a matching constructor is not found,
2515 * including when this {@code Class} object represents
2516 * an interface, a primitive type, an array class, or void.
2517 *
2518 * @see #getConstructor(Class[])
2519 * @since 1.1
2520 */
2521 public Constructor<T> getDeclaredConstructor(Class<?>... parameterTypes)
2522 throws NoSuchMethodException {
2523 return getReflectionFactory().copyConstructor(
2524 getConstructor0(parameterTypes, Member.DECLARED));
2525 }
2526
2527 /**
2528 * Finds a resource with a given name.
2529 *
2530 * <p> If this class is in a named {@link Module Module} then this method
2531 * will attempt to find the resource in the module. This is done by
2532 * delegating to the module's class loader {@link
2533 * ClassLoader#findResource(String,String) findResource(String,String)}
2534 * method, invoking it with the module name and the absolute name of the
2535 * resource. Resources in named modules are subject to the rules for
2536 * encapsulation specified in the {@code Module} {@link
2537 * Module#getResourceAsStream getResourceAsStream} method and so this
2538 * method returns {@code null} when the resource is a
2539 * non-"{@code .class}" resource in a package that is not open to the
2540 * caller's module.
2541 *
2542 * <p> Otherwise, if this class is not in a named module then the rules for
2543 * searching resources associated with a given class are implemented by the
2544 * defining {@linkplain ClassLoader class loader} of the class. This method
2545 * delegates to this {@code Class} object's class loader.
2546 * If this {@code Class} object was loaded by the bootstrap class loader,
2547 * the method delegates to {@link ClassLoader#getSystemResourceAsStream}.
2548 *
2549 * <p> Before delegation, an absolute resource name is constructed from the
2550 * given resource name using this algorithm:
2551 *
2552 * <ul>
2553 *
2554 * <li> If the {@code name} begins with a {@code '/'}
2555 * (<code>'\u002f'</code>), then the absolute name of the resource is the
2556 * portion of the {@code name} following the {@code '/'}.
2557 *
2558 * <li> Otherwise, the absolute name is of the following form:
2559 *
2560 * <blockquote>
2561 * {@code modified_package_name/name}
2562 * </blockquote>
2563 *
2564 * <p> Where the {@code modified_package_name} is the package name of this
2565 * object with {@code '/'} substituted for {@code '.'}
2566 * (<code>'\u002e'</code>).
2567 *
2568 * </ul>
2569 *
2570 * @param name name of the desired resource
2571 * @return A {@link java.io.InputStream} object; {@code null} if no
2572 * resource with this name is found, or the resource is in a package
2573 * that is not {@linkplain Module#isOpen(String, Module) open} to at
2574 * least the caller module.
2575 * @throws NullPointerException If {@code name} is {@code null}
2576 *
2577 * @see Module#getResourceAsStream(String)
2578 * @since 1.1
2579 */
2580 @CallerSensitive
2581 public InputStream getResourceAsStream(String name) {
2582 name = resolveName(name);
2583
2584 Module thisModule = getModule();
2585 if (thisModule.isNamed()) {
2586 // check if resource can be located by caller
2587 if (Resources.canEncapsulate(name)
2588 && !isOpenToCaller(name, Reflection.getCallerClass())) {
2589 return null;
2590 }
2591
2592 // resource not encapsulated or in package open to caller
2593 String mn = thisModule.getName();
2594 ClassLoader cl = classLoader;
2595 try {
2596
2597 // special-case built-in class loaders to avoid the
2598 // need for a URL connection
2599 if (cl == null) {
2600 return BootLoader.findResourceAsStream(mn, name);
2601 } else if (cl instanceof BuiltinClassLoader bcl) {
2602 return bcl.findResourceAsStream(mn, name);
2603 } else {
2604 URL url = cl.findResource(mn, name);
2605 return (url != null) ? url.openStream() : null;
2606 }
2607
2608 } catch (IOException | SecurityException e) {
2609 return null;
2610 }
2611 }
2612
2613 // unnamed module
2614 ClassLoader cl = classLoader;
2615 if (cl == null) {
2616 return ClassLoader.getSystemResourceAsStream(name);
2617 } else {
2618 return cl.getResourceAsStream(name);
2619 }
2620 }
2621
2622 /**
2623 * Finds a resource with a given name.
2624 *
2625 * <p> If this class is in a named {@link Module Module} then this method
2626 * will attempt to find the resource in the module. This is done by
2627 * delegating to the module's class loader {@link
2628 * ClassLoader#findResource(String,String) findResource(String,String)}
2629 * method, invoking it with the module name and the absolute name of the
2630 * resource. Resources in named modules are subject to the rules for
2631 * encapsulation specified in the {@code Module} {@link
2632 * Module#getResourceAsStream getResourceAsStream} method and so this
2633 * method returns {@code null} when the resource is a
2634 * non-"{@code .class}" resource in a package that is not open to the
2635 * caller's module.
2636 *
2637 * <p> Otherwise, if this class is not in a named module then the rules for
2638 * searching resources associated with a given class are implemented by the
2639 * defining {@linkplain ClassLoader class loader} of the class. This method
2640 * delegates to this {@code Class} object's class loader.
2641 * If this {@code Class} object was loaded by the bootstrap class loader,
2642 * the method delegates to {@link ClassLoader#getSystemResource}.
2643 *
2644 * <p> Before delegation, an absolute resource name is constructed from the
2645 * given resource name using this algorithm:
2646 *
2647 * <ul>
2648 *
2649 * <li> If the {@code name} begins with a {@code '/'}
2650 * (<code>'\u002f'</code>), then the absolute name of the resource is the
2651 * portion of the {@code name} following the {@code '/'}.
2652 *
2653 * <li> Otherwise, the absolute name is of the following form:
2654 *
2655 * <blockquote>
2656 * {@code modified_package_name/name}
2657 * </blockquote>
2658 *
2659 * <p> Where the {@code modified_package_name} is the package name of this
2660 * object with {@code '/'} substituted for {@code '.'}
2661 * (<code>'\u002e'</code>).
2662 *
2663 * </ul>
2664 *
2665 * @param name name of the desired resource
2666 * @return A {@link java.net.URL} object; {@code null} if no resource with
2667 * this name is found, the resource cannot be located by a URL, or the
2668 * resource is in a package that is not
2669 * {@linkplain Module#isOpen(String, Module) open} to at least the caller
2670 * module.
2671 * @throws NullPointerException If {@code name} is {@code null}
2672 * @since 1.1
2673 */
2674 @CallerSensitive
2675 public URL getResource(String name) {
2676 name = resolveName(name);
2677
2678 Module thisModule = getModule();
2679 if (thisModule.isNamed()) {
2680 // check if resource can be located by caller
2681 if (Resources.canEncapsulate(name)
2682 && !isOpenToCaller(name, Reflection.getCallerClass())) {
2683 return null;
2684 }
2685
2686 // resource not encapsulated or in package open to caller
2687 String mn = thisModule.getName();
2688 ClassLoader cl = classLoader;
2689 try {
2690 if (cl == null) {
2691 return BootLoader.findResource(mn, name);
2692 } else {
2693 return cl.findResource(mn, name);
2694 }
2695 } catch (IOException ioe) {
2696 return null;
2697 }
2698 }
2699
2700 // unnamed module
2701 ClassLoader cl = classLoader;
2702 if (cl == null) {
2703 return ClassLoader.getSystemResource(name);
2704 } else {
2705 return cl.getResource(name);
2706 }
2707 }
2708
2709 /**
2710 * Returns true if a resource with the given name can be located by the
2711 * given caller. All resources in a module can be located by code in
2712 * the module. For other callers, then the package needs to be open to
2713 * the caller.
2714 */
2715 private boolean isOpenToCaller(String name, Class<?> caller) {
2716 // assert getModule().isNamed();
2717 Module thisModule = getModule();
2718 Module callerModule = (caller != null) ? caller.getModule() : null;
2719 if (callerModule != thisModule) {
2720 String pn = Resources.toPackageName(name);
2721 if (thisModule.getDescriptor().packages().contains(pn)) {
2722 if (callerModule == null) {
2723 // no caller, return true if the package is open to all modules
2724 return thisModule.isOpen(pn);
2725 }
2726 if (!thisModule.isOpen(pn, callerModule)) {
2727 // package not open to caller
2728 return false;
2729 }
2730 }
2731 }
2732 return true;
2733 }
2734
2735 private transient final ProtectionDomain protectionDomain;
2736
2737 /** Holder for the protection domain returned when the internal domain is null */
2738 private static class Holder {
2739 private static final ProtectionDomain allPermDomain;
2740 static {
2741 Permissions perms = new Permissions();
2742 perms.add(new AllPermission());
2743 allPermDomain = new ProtectionDomain(null, perms);
2744 }
2745 }
2746
2747 /**
2748 * Returns the {@code ProtectionDomain} of this class.
2749 *
2750 * @return the ProtectionDomain of this class
2751 *
2752 * @see java.security.ProtectionDomain
2753 * @since 1.2
2754 */
2755 public ProtectionDomain getProtectionDomain() {
2756 if (protectionDomain == null) {
2757 return Holder.allPermDomain;
2758 } else {
2759 return protectionDomain;
2760 }
2761 }
2762
2763 /*
2764 * Returns the Class object for the named primitive type. Type parameter T
2765 * avoids redundant casts for trusted code.
2766 */
2767 static native <T> Class<T> getPrimitiveClass(String name);
2768
2769 /**
2770 * Add a package name prefix if the name is not absolute. Remove leading "/"
2771 * if name is absolute
2772 */
2773 private String resolveName(String name) {
2774 if (!name.startsWith("/")) {
2775 String baseName = getPackageName();
2776 if (!baseName.isEmpty()) {
2777 int len = baseName.length() + 1 + name.length();
2778 StringBuilder sb = new StringBuilder(len);
2779 name = sb.append(baseName.replace('.', '/'))
2780 .append('/')
2781 .append(name)
2782 .toString();
2783 }
2784 } else {
2785 name = name.substring(1);
2786 }
2787 return name;
2788 }
2789
2790 /**
2791 * Atomic operations support.
2792 */
2793 private static class Atomic {
2794 // initialize Unsafe machinery here, since we need to call Class.class instance method
2795 // and have to avoid calling it in the static initializer of the Class class...
2796 private static final Unsafe unsafe = Unsafe.getUnsafe();
2797 // offset of Class.reflectionData instance field
2798 private static final long reflectionDataOffset
2799 = unsafe.objectFieldOffset(Class.class, "reflectionData");
2800 // offset of Class.annotationType instance field
2801 private static final long annotationTypeOffset
2802 = unsafe.objectFieldOffset(Class.class, "annotationType");
2803 // offset of Class.annotationData instance field
2804 private static final long annotationDataOffset
2805 = unsafe.objectFieldOffset(Class.class, "annotationData");
2806
2807 static <T> boolean casReflectionData(Class<?> clazz,
2808 ReflectionData<T> oldData,
2809 ReflectionData<T> newData) {
2810 return unsafe.compareAndSetReference(clazz, reflectionDataOffset, oldData, newData);
2811 }
2812
2813 static boolean casAnnotationType(Class<?> clazz,
2814 AnnotationType oldType,
2815 AnnotationType newType) {
2816 return unsafe.compareAndSetReference(clazz, annotationTypeOffset, oldType, newType);
2817 }
2818
2819 static boolean casAnnotationData(Class<?> clazz,
2820 AnnotationData oldData,
2821 AnnotationData newData) {
2822 return unsafe.compareAndSetReference(clazz, annotationDataOffset, oldData, newData);
2823 }
2824 }
2825
2826 /**
2827 * Reflection support.
2828 */
2829
2830 // Reflection data caches various derived names and reflective members. Cached
2831 // values may be invalidated when JVM TI RedefineClasses() is called
2832 private static class ReflectionData<T> {
2833 volatile Field[] declaredFields;
2834 volatile Field[] publicFields;
2835 volatile Method[] declaredMethods;
2836 volatile Method[] publicMethods;
2837 volatile Constructor<T>[] declaredConstructors;
2838 volatile Constructor<T>[] publicConstructors;
2839 // Intermediate results for getFields and getMethods
2840 volatile Field[] declaredPublicFields;
2841 volatile Method[] declaredPublicMethods;
2842 volatile Class<?>[] interfaces;
2843
2844 // Cached names
2845 String simpleName;
2846 String canonicalName;
2847 static final String NULL_SENTINEL = new String();
2848
2849 // Value of classRedefinedCount when we created this ReflectionData instance
2850 final int redefinedCount;
2851
2852 ReflectionData(int redefinedCount) {
2853 this.redefinedCount = redefinedCount;
2854 }
2855 }
2856
2857 private transient volatile ReflectionData<T> reflectionData;
2858
2859 // Incremented by the VM on each call to JVM TI RedefineClasses()
2860 // that redefines this class or a superclass.
2861 private transient volatile int classRedefinedCount;
2862
2863 // Lazily create and cache ReflectionData
2864 private ReflectionData<T> reflectionData() {
2865 ReflectionData<T> reflectionData = this.reflectionData;
2866 int classRedefinedCount = this.classRedefinedCount;
2867 if (reflectionData != null &&
2868 reflectionData.redefinedCount == classRedefinedCount) {
2869 return reflectionData;
2870 }
2871 // else no SoftReference or cleared SoftReference or stale ReflectionData
2872 // -> create and replace new instance
2873 return newReflectionData(reflectionData, classRedefinedCount);
2874 }
2875
2876 private ReflectionData<T> newReflectionData(ReflectionData<T> oldReflectionData,
2877 int classRedefinedCount) {
2878 while (true) {
2879 ReflectionData<T> rd = new ReflectionData<>(classRedefinedCount);
2880 // try to CAS it...
2881 if (Atomic.casReflectionData(this, oldReflectionData, rd)) {
2882 return rd;
2883 }
2884 // else retry
2885 oldReflectionData = this.reflectionData;
2886 classRedefinedCount = this.classRedefinedCount;
2887 if (oldReflectionData != null && oldReflectionData.redefinedCount == classRedefinedCount) {
2888 return rd;
2889 }
2890 }
2891 }
2892
2893 // Generic signature handling
2894 private native String getGenericSignature0();
2895
2896 // Generic info repository; lazily initialized
2897 private transient volatile ClassRepository genericInfo;
2898
2899 // accessor for factory
2900 private GenericsFactory getFactory() {
2901 // create scope and factory
2902 return CoreReflectionFactory.make(this, ClassScope.make(this));
2903 }
2904
2905 // accessor for generic info repository;
2906 // generic info is lazily initialized
2907 private ClassRepository getGenericInfo() {
2908 ClassRepository genericInfo = this.genericInfo;
2909 if (genericInfo == null) {
2910 String signature = getGenericSignature0();
2911 if (signature == null) {
2912 genericInfo = ClassRepository.NONE;
2913 } else {
2914 genericInfo = ClassRepository.make(signature, getFactory());
2915 }
2916 this.genericInfo = genericInfo;
2917 }
2918 return (genericInfo != ClassRepository.NONE) ? genericInfo : null;
2919 }
2920
2921 // Annotations handling
2922 native byte[] getRawAnnotations();
2923 // Since 1.8
2924 native byte[] getRawTypeAnnotations();
2925 static byte[] getExecutableTypeAnnotationBytes(Executable ex) {
2926 return getReflectionFactory().getExecutableTypeAnnotationBytes(ex);
2927 }
2928
2929 native ConstantPool getConstantPool();
2930
2931 //
2932 //
2933 // java.lang.reflect.Field handling
2934 //
2935 //
2936
2937 // Returns an array of "root" fields. These Field objects must NOT
2938 // be propagated to the outside world, but must instead be copied
2939 // via ReflectionFactory.copyField.
2940 private Field[] privateGetDeclaredFields(boolean publicOnly) {
2941 Field[] res;
2942 ReflectionData<T> rd = reflectionData();
2943 res = publicOnly ? rd.declaredPublicFields : rd.declaredFields;
2944 if (res != null) return res;
2945 // No cached value available; request value from VM
2946 res = Reflection.filterFields(this, getDeclaredFields0(publicOnly));
2947 if (publicOnly) {
2948 rd.declaredPublicFields = res;
2949 } else {
2950 rd.declaredFields = res;
2951 }
2952 return res;
2953 }
2954
2955 // Returns an array of "root" fields. These Field objects must NOT
2956 // be propagated to the outside world, but must instead be copied
2957 // via ReflectionFactory.copyField.
2958 private Field[] privateGetPublicFields() {
2959 Field[] res;
2960 ReflectionData<T> rd = reflectionData();
2961 res = rd.publicFields;
2962 if (res != null) return res;
2963
2964 // Use a linked hash set to ensure order is preserved and
2965 // fields from common super interfaces are not duplicated
2966 LinkedHashSet<Field> fields = new LinkedHashSet<>();
2967
2968 // Local fields
2969 addAll(fields, privateGetDeclaredFields(true));
2970
2971 // Direct superinterfaces, recursively
2972 for (Class<?> si : getInterfaces(/* cloneArray */ false)) {
2973 addAll(fields, si.privateGetPublicFields());
2974 }
2975
2976 // Direct superclass, recursively
2977 Class<?> sc = getSuperclass();
2978 if (sc != null) {
2979 addAll(fields, sc.privateGetPublicFields());
2980 }
2981
2982 res = fields.toArray(new Field[0]);
2983 rd.publicFields = res;
2984 return res;
2985 }
2986
2987 private static void addAll(Collection<Field> c, Field[] o) {
2988 for (Field f : o) {
2989 c.add(f);
2990 }
2991 }
2992
2993
2994 //
2995 //
2996 // java.lang.reflect.Constructor handling
2997 //
2998 //
2999
3000 // Returns an array of "root" constructors. These Constructor
3001 // objects must NOT be propagated to the outside world, but must
3002 // instead be copied via ReflectionFactory.copyConstructor.
3003 private Constructor<T>[] privateGetDeclaredConstructors(boolean publicOnly) {
3004 Constructor<T>[] res;
3005 ReflectionData<T> rd = reflectionData();
3006 res = publicOnly ? rd.publicConstructors : rd.declaredConstructors;
3007 if (res != null) return res;
3008 // No cached value available; request value from VM
3009 if (isInterface()) {
3010 @SuppressWarnings("unchecked")
3011 Constructor<T>[] temporaryRes = (Constructor<T>[]) new Constructor<?>[0];
3012 res = temporaryRes;
3013 } else {
3014 res = getDeclaredConstructors0(publicOnly);
3015 }
3016 if (publicOnly) {
3017 rd.publicConstructors = res;
3018 } else {
3019 rd.declaredConstructors = res;
3020 }
3021 return res;
3022 }
3023
3024 //
3025 //
3026 // java.lang.reflect.Method handling
3027 //
3028 //
3029
3030 // Returns an array of "root" methods. These Method objects must NOT
3031 // be propagated to the outside world, but must instead be copied
3032 // via ReflectionFactory.copyMethod.
3033 private Method[] privateGetDeclaredMethods(boolean publicOnly) {
3034 Method[] res;
3035 ReflectionData<T> rd = reflectionData();
3036 res = publicOnly ? rd.declaredPublicMethods : rd.declaredMethods;
3037 if (res != null) return res;
3038 // No cached value available; request value from VM
3039 res = Reflection.filterMethods(this, getDeclaredMethods0(publicOnly));
3040 if (publicOnly) {
3041 rd.declaredPublicMethods = res;
3042 } else {
3043 rd.declaredMethods = res;
3044 }
3045 return res;
3046 }
3047
3048 // Returns an array of "root" methods. These Method objects must NOT
3049 // be propagated to the outside world, but must instead be copied
3050 // via ReflectionFactory.copyMethod.
3051 private Method[] privateGetPublicMethods() {
3052 Method[] res;
3053 ReflectionData<T> rd = reflectionData();
3054 res = rd.publicMethods;
3055 if (res != null) return res;
3056
3057 // No cached value available; compute value recursively.
3058 // Start by fetching public declared methods...
3059 PublicMethods pms = new PublicMethods();
3060 for (Method m : privateGetDeclaredMethods(/* publicOnly */ true)) {
3061 pms.merge(m);
3062 }
3063 // ...then recur over superclass methods...
3064 Class<?> sc = getSuperclass();
3065 if (sc != null) {
3066 for (Method m : sc.privateGetPublicMethods()) {
3067 pms.merge(m);
3068 }
3069 }
3070 // ...and finally over direct superinterfaces.
3071 for (Class<?> intf : getInterfaces(/* cloneArray */ false)) {
3072 for (Method m : intf.privateGetPublicMethods()) {
3073 // static interface methods are not inherited
3074 if (!Modifier.isStatic(m.getModifiers())) {
3075 pms.merge(m);
3076 }
3077 }
3078 }
3079
3080 res = pms.toArray();
3081 rd.publicMethods = res;
3082 return res;
3083 }
3084
3085
3086 //
3087 // Helpers for fetchers of one field, method, or constructor
3088 //
3089
3090 // This method does not copy the returned Field object!
3091 private static Field searchFields(Field[] fields, String name) {
3092 for (Field field : fields) {
3093 if (field.getName().equals(name)) {
3094 return field;
3095 }
3096 }
3097 return null;
3098 }
3099
3100 // Returns a "root" Field object. This Field object must NOT
3101 // be propagated to the outside world, but must instead be copied
3102 // via ReflectionFactory.copyField.
3103 private Field getField0(String name) {
3104 // Note: the intent is that the search algorithm this routine
3105 // uses be equivalent to the ordering imposed by
3106 // privateGetPublicFields(). It fetches only the declared
3107 // public fields for each class, however, to reduce the number
3108 // of Field objects which have to be created for the common
3109 // case where the field being requested is declared in the
3110 // class which is being queried.
3111 Field res;
3112 // Search declared public fields
3113 if ((res = searchFields(privateGetDeclaredFields(true), name)) != null) {
3114 return res;
3115 }
3116 // Direct superinterfaces, recursively
3117 Class<?>[] interfaces = getInterfaces(/* cloneArray */ false);
3118 for (Class<?> c : interfaces) {
3119 if ((res = c.getField0(name)) != null) {
3120 return res;
3121 }
3122 }
3123 // Direct superclass, recursively
3124 if (!isInterface()) {
3125 Class<?> c = getSuperclass();
3126 if (c != null) {
3127 if ((res = c.getField0(name)) != null) {
3128 return res;
3129 }
3130 }
3131 }
3132 return null;
3133 }
3134
3135 // This method does not copy the returned Method object!
3136 private static Method searchMethods(Method[] methods,
3137 String name,
3138 Class<?>[] parameterTypes)
3139 {
3140 ReflectionFactory fact = getReflectionFactory();
3141 Method res = null;
3142 for (Method m : methods) {
3143 if (m.getName().equals(name)
3144 && arrayContentsEq(parameterTypes,
3145 fact.getExecutableSharedParameterTypes(m))
3146 && (res == null
3147 || (res.getReturnType() != m.getReturnType()
3148 && res.getReturnType().isAssignableFrom(m.getReturnType()))))
3149 res = m;
3150 }
3151 return res;
3152 }
3153
3154 private static final Class<?>[] EMPTY_CLASS_ARRAY = new Class<?>[0];
3155
3156 // Returns a "root" Method object. This Method object must NOT
3157 // be propagated to the outside world, but must instead be copied
3158 // via ReflectionFactory.copyMethod.
3159 private Method getMethod0(String name, Class<?>[] parameterTypes) {
3160 PublicMethods.MethodList res = getMethodsRecursive(
3161 name,
3162 parameterTypes == null ? EMPTY_CLASS_ARRAY : parameterTypes,
3163 /* includeStatic */ true, /* publicOnly */ true);
3164 return res == null ? null : res.getMostSpecific();
3165 }
3166
3167 // Returns a list of "root" Method objects. These Method objects must NOT
3168 // be propagated to the outside world, but must instead be copied
3169 // via ReflectionFactory.copyMethod.
3170 private PublicMethods.MethodList getMethodsRecursive(String name,
3171 Class<?>[] parameterTypes,
3172 boolean includeStatic,
3173 boolean publicOnly) {
3174 // 1st check declared methods
3175 Method[] methods = privateGetDeclaredMethods(publicOnly);
3176 PublicMethods.MethodList res = PublicMethods.MethodList
3177 .filter(methods, name, parameterTypes, includeStatic);
3178 // if there is at least one match among declared methods, we need not
3179 // search any further as such match surely overrides matching methods
3180 // declared in superclass(es) or interface(s).
3181 if (res != null) {
3182 return res;
3183 }
3184
3185 // if there was no match among declared methods,
3186 // we must consult the superclass (if any) recursively...
3187 Class<?> sc = getSuperclass();
3188 if (sc != null) {
3189 res = sc.getMethodsRecursive(name, parameterTypes, includeStatic, publicOnly);
3190 }
3191
3192 // ...and coalesce the superclass methods with methods obtained
3193 // from directly implemented interfaces excluding static methods...
3194 for (Class<?> intf : getInterfaces(/* cloneArray */ false)) {
3195 res = PublicMethods.MethodList.merge(
3196 res, intf.getMethodsRecursive(name, parameterTypes, /* includeStatic */ false, publicOnly));
3197 }
3198
3199 return res;
3200 }
3201
3202 // Returns a "root" Constructor object. This Constructor object must NOT
3203 // be propagated to the outside world, but must instead be copied
3204 // via ReflectionFactory.copyConstructor.
3205 private Constructor<T> getConstructor0(Class<?>[] parameterTypes,
3206 int which) throws NoSuchMethodException
3207 {
3208 ReflectionFactory fact = getReflectionFactory();
3209 Constructor<T>[] constructors = privateGetDeclaredConstructors((which == Member.PUBLIC));
3210 for (Constructor<T> constructor : constructors) {
3211 if (arrayContentsEq(parameterTypes,
3212 fact.getExecutableSharedParameterTypes(constructor))) {
3213 return constructor;
3214 }
3215 }
3216 throw new NoSuchMethodException(methodToString("<init>", parameterTypes));
3217 }
3218
3219 //
3220 // Other helpers and base implementation
3221 //
3222
3223 private static boolean arrayContentsEq(Object[] a1, Object[] a2) {
3224 if (a1 == null) {
3225 return a2 == null || a2.length == 0;
3226 }
3227
3228 if (a2 == null) {
3229 return a1.length == 0;
3230 }
3231
3232 if (a1.length != a2.length) {
3233 return false;
3234 }
3235
3236 for (int i = 0; i < a1.length; i++) {
3237 if (a1[i] != a2[i]) {
3238 return false;
3239 }
3240 }
3241
3242 return true;
3243 }
3244
3245 private static Field[] copyFields(Field[] arg) {
3246 Field[] out = new Field[arg.length];
3247 ReflectionFactory fact = getReflectionFactory();
3248 for (int i = 0; i < arg.length; i++) {
3249 out[i] = fact.copyField(arg[i]);
3250 }
3251 return out;
3252 }
3253
3254 private static Method[] copyMethods(Method[] arg) {
3255 Method[] out = new Method[arg.length];
3256 ReflectionFactory fact = getReflectionFactory();
3257 for (int i = 0; i < arg.length; i++) {
3258 out[i] = fact.copyMethod(arg[i]);
3259 }
3260 return out;
3261 }
3262
3263 private static <U> Constructor<U>[] copyConstructors(Constructor<U>[] arg) {
3264 Constructor<U>[] out = arg.clone();
3265 ReflectionFactory fact = getReflectionFactory();
3266 for (int i = 0; i < out.length; i++) {
3267 out[i] = fact.copyConstructor(out[i]);
3268 }
3269 return out;
3270 }
3271
3272 private native Field[] getDeclaredFields0(boolean publicOnly);
3273 private native Method[] getDeclaredMethods0(boolean publicOnly);
3274 private native Constructor<T>[] getDeclaredConstructors0(boolean publicOnly);
3275 private native Class<?>[] getDeclaredClasses0();
3276
3277 /*
3278 * Returns an array containing the components of the Record attribute,
3279 * or null if the attribute is not present.
3280 *
3281 * Note that this method returns non-null array on a class with
3282 * the Record attribute even if this class is not a record.
3283 */
3284 private native RecordComponent[] getRecordComponents0();
3285 private native boolean isRecord0();
3286
3287 /**
3288 * Helper method to get the method name from arguments.
3289 */
3290 private String methodToString(String name, Class<?>[] argTypes) {
3291 return getName() + '.' + name +
3292 ((argTypes == null || argTypes.length == 0) ?
3293 "()" :
3294 Arrays.stream(argTypes)
3295 .map(c -> c == null ? "null" : c.getName())
3296 .collect(Collectors.joining(",", "(", ")")));
3297 }
3298
3299 /** use serialVersionUID from JDK 1.1 for interoperability */
3300 @java.io.Serial
3301 private static final long serialVersionUID = 3206093459760846163L;
3302
3303
3304 /**
3305 * Class Class is special cased within the Serialization Stream Protocol.
3306 *
3307 * A Class instance is written initially into an ObjectOutputStream in the
3308 * following format:
3309 * <pre>
3310 * {@code TC_CLASS} ClassDescriptor
3311 * A ClassDescriptor is a special cased serialization of
3312 * a {@code java.io.ObjectStreamClass} instance.
3313 * </pre>
3314 * A new handle is generated for the initial time the class descriptor
3315 * is written into the stream. Future references to the class descriptor
3316 * are written as references to the initial class descriptor instance.
3317 *
3318 * @see java.io.ObjectStreamClass
3319 */
3320 @java.io.Serial
3321 private static final ObjectStreamField[] serialPersistentFields =
3322 new ObjectStreamField[0];
3323
3324
3325 /**
3326 * Returns the assertion status that would be assigned to this
3327 * class if it were to be initialized at the time this method is invoked.
3328 * If this class has had its assertion status set, the most recent
3329 * setting will be returned; otherwise, if any package default assertion
3330 * status pertains to this class, the most recent setting for the most
3331 * specific pertinent package default assertion status is returned;
3332 * otherwise, if this class is not a system class (i.e., it has a
3333 * class loader) its class loader's default assertion status is returned;
3334 * otherwise, the system class default assertion status is returned.
3335 *
3336 * @apiNote
3337 * Few programmers will have any need for this method; it is provided
3338 * for the benefit of the JDK itself. (It allows a class to determine at
3339 * the time that it is initialized whether assertions should be enabled.)
3340 * Note that this method is not guaranteed to return the actual
3341 * assertion status that was (or will be) associated with the specified
3342 * class when it was (or will be) initialized.
3343 *
3344 * @return the desired assertion status of the specified class.
3345 * @see java.lang.ClassLoader#setClassAssertionStatus
3346 * @see java.lang.ClassLoader#setPackageAssertionStatus
3347 * @see java.lang.ClassLoader#setDefaultAssertionStatus
3348 * @since 1.4
3349 */
3350 public boolean desiredAssertionStatus() {
3351 ClassLoader loader = classLoader;
3352 // If the loader is null this is a system class, so ask the VM
3353 if (loader == null)
3354 return desiredAssertionStatus0(this);
3355
3356 // If the classloader has been initialized with the assertion
3357 // directives, ask it. Otherwise, ask the VM.
3358 synchronized(loader.assertionLock) {
3359 if (loader.classAssertionStatus != null) {
3360 return loader.desiredAssertionStatus(getName());
3361 }
3362 }
3363 return desiredAssertionStatus0(this);
3364 }
3365
3366 // Retrieves the desired assertion status of this class from the VM
3367 private static native boolean desiredAssertionStatus0(Class<?> clazz);
3368
3369 /**
3370 * Returns true if and only if this class was declared as an enum in the
3371 * source code.
3372 *
3373 * Note that {@link java.lang.Enum} is not itself an enum class.
3374 *
3375 * Also note that if an enum constant is declared with a class body,
3376 * the class of that enum constant object is an anonymous class
3377 * and <em>not</em> the class of the declaring enum class. The
3378 * {@link Enum#getDeclaringClass} method of an enum constant can
3379 * be used to get the class of the enum class declaring the
3380 * constant.
3381 *
3382 * @return true if and only if this class was declared as an enum in the
3383 * source code
3384 * @since 1.5
3385 * @jls 8.9.1 Enum Constants
3386 */
3387 public boolean isEnum() {
3388 // An enum must both directly extend java.lang.Enum and have
3389 // the ENUM bit set; classes for specialized enum constants
3390 // don't do the former.
3391 return (this.getModifiers() & ENUM) != 0 &&
3392 this.getSuperclass() == java.lang.Enum.class;
3393 }
3394
3395 /**
3396 * Returns {@code true} if and only if this class is a record class.
3397 *
3398 * <p> The {@linkplain #getSuperclass() direct superclass} of a record
3399 * class is {@code java.lang.Record}. A record class is {@linkplain
3400 * Modifier#FINAL final}. A record class has (possibly zero) record
3401 * components; {@link #getRecordComponents()} returns a non-null but
3402 * possibly empty value for a record.
3403 *
3404 * <p> Note that class {@link Record} is not a record class and thus
3405 * invoking this method on class {@code Record} returns {@code false}.
3406 *
3407 * @return true if and only if this class is a record class, otherwise false
3408 * @jls 8.10 Record Classes
3409 * @since 16
3410 */
3411 public boolean isRecord() {
3412 // this superclass and final modifier check is not strictly necessary
3413 // they are intrinsified and serve as a fast-path check
3414 return getSuperclass() == java.lang.Record.class &&
3415 (this.getModifiers() & Modifier.FINAL) != 0 &&
3416 isRecord0();
3417 }
3418
3419 // Fetches the factory for reflective objects
3420 private static ReflectionFactory getReflectionFactory() {
3421 var factory = reflectionFactory;
3422 if (factory != null) {
3423 return factory;
3424 }
3425 return reflectionFactory = ReflectionFactory.getReflectionFactory();
3426 }
3427 private static ReflectionFactory reflectionFactory;
3428
3429 /**
3430 * When CDS is enabled, the Class class may be aot-initialized. However,
3431 * we can't archive reflectionFactory, so we reset it to null, so it
3432 * will be allocated again at runtime.
3433 */
3434 private static void resetArchivedStates() {
3435 reflectionFactory = null;
3436 }
3437
3438 /**
3439 * Returns the elements of this enum class or null if this
3440 * Class object does not represent an enum class.
3441 *
3442 * @return an array containing the values comprising the enum class
3443 * represented by this {@code Class} object in the order they're
3444 * declared, or null if this {@code Class} object does not
3445 * represent an enum class
3446 * @since 1.5
3447 * @jls 8.9.1 Enum Constants
3448 */
3449 public T[] getEnumConstants() {
3450 T[] values = getEnumConstantsShared();
3451 return (values != null) ? values.clone() : null;
3452 }
3453
3454 /**
3455 * Returns the elements of this enum class or null if this
3456 * Class object does not represent an enum class;
3457 * identical to getEnumConstants except that the result is
3458 * uncloned, cached, and shared by all callers.
3459 */
3460 T[] getEnumConstantsShared() {
3461 T[] constants = enumConstants;
3462 if (constants == null) {
3463 if (!isEnum()) return null;
3464 try {
3465 final Method values = getMethod("values");
3466 values.setAccessible(true);
3467 @SuppressWarnings("unchecked")
3468 T[] temporaryConstants = (T[])values.invoke(null);
3469 enumConstants = constants = temporaryConstants;
3470 }
3471 // These can happen when users concoct enum-like classes
3472 // that don't comply with the enum spec.
3473 catch (InvocationTargetException | NoSuchMethodException |
3474 IllegalAccessException | NullPointerException |
3475 ClassCastException ex) { return null; }
3476 }
3477 return constants;
3478 }
3479 private transient volatile T[] enumConstants;
3480
3481 /**
3482 * Returns a map from simple name to enum constant. This package-private
3483 * method is used internally by Enum to implement
3484 * {@code public static <T extends Enum<T>> T valueOf(Class<T>, String)}
3485 * efficiently. Note that the map is returned by this method is
3486 * created lazily on first use. Typically it won't ever get created.
3487 */
3488 Map<String, T> enumConstantDirectory() {
3489 Map<String, T> directory = enumConstantDirectory;
3490 if (directory == null) {
3491 T[] universe = getEnumConstantsShared();
3492 if (universe == null)
3493 throw new IllegalArgumentException(
3494 getName() + " is not an enum class");
3495 directory = HashMap.newHashMap(universe.length);
3496 for (T constant : universe) {
3497 directory.put(((Enum<?>)constant).name(), constant);
3498 }
3499 enumConstantDirectory = directory;
3500 }
3501 return directory;
3502 }
3503 private transient volatile Map<String, T> enumConstantDirectory;
3504
3505 /**
3506 * Casts an object to the class or interface represented
3507 * by this {@code Class} object.
3508 *
3509 * @param obj the object to be cast
3510 * @return the object after casting, or null if obj is null
3511 *
3512 * @throws ClassCastException if the object is not
3513 * null and is not assignable to the type T.
3514 *
3515 * @since 1.5
3516 */
3517 @SuppressWarnings("unchecked")
3518 @IntrinsicCandidate
3519 public T cast(Object obj) {
3520 if (obj != null && !isInstance(obj))
3521 throw new ClassCastException(cannotCastMsg(obj));
3522 return (T) obj;
3523 }
3524
3525 private String cannotCastMsg(Object obj) {
3526 return "Cannot cast " + obj.getClass().getName() + " to " + getName();
3527 }
3528
3529 /**
3530 * Casts this {@code Class} object to represent a subclass of the class
3531 * represented by the specified class object. Checks that the cast
3532 * is valid, and throws a {@code ClassCastException} if it is not. If
3533 * this method succeeds, it always returns a reference to this {@code Class} object.
3534 *
3535 * <p>This method is useful when a client needs to "narrow" the type of
3536 * a {@code Class} object to pass it to an API that restricts the
3537 * {@code Class} objects that it is willing to accept. A cast would
3538 * generate a compile-time warning, as the correctness of the cast
3539 * could not be checked at runtime (because generic types are implemented
3540 * by erasure).
3541 *
3542 * @param <U> the type to cast this {@code Class} object to
3543 * @param clazz the class of the type to cast this {@code Class} object to
3544 * @return this {@code Class} object, cast to represent a subclass of
3545 * the specified class object.
3546 * @throws ClassCastException if this {@code Class} object does not
3547 * represent a subclass of the specified class (here "subclass" includes
3548 * the class itself).
3549 * @since 1.5
3550 */
3551 @SuppressWarnings("unchecked")
3552 public <U> Class<? extends U> asSubclass(Class<U> clazz) {
3553 if (clazz.isAssignableFrom(this))
3554 return (Class<? extends U>) this;
3555 else
3556 throw new ClassCastException(this.toString());
3557 }
3558
3559 /**
3560 * {@inheritDoc}
3561 * <p>Note that any annotation returned by this method is a
3562 * declaration annotation.
3563 *
3564 * @throws NullPointerException {@inheritDoc}
3565 * @since 1.5
3566 */
3567 @Override
3568 @SuppressWarnings("unchecked")
3569 public <A extends Annotation> A getAnnotation(Class<A> annotationClass) {
3570 Objects.requireNonNull(annotationClass);
3571
3572 return (A) annotationData().annotations.get(annotationClass);
3573 }
3574
3575 /**
3576 * {@inheritDoc}
3577 * @throws NullPointerException {@inheritDoc}
3578 * @since 1.5
3579 */
3580 @Override
3581 public boolean isAnnotationPresent(Class<? extends Annotation> annotationClass) {
3582 return GenericDeclaration.super.isAnnotationPresent(annotationClass);
3583 }
3584
3585 /**
3586 * {@inheritDoc}
3587 * <p>Note that any annotations returned by this method are
3588 * declaration annotations.
3589 *
3590 * @throws NullPointerException {@inheritDoc}
3591 * @since 1.8
3592 */
3593 @Override
3594 public <A extends Annotation> A[] getAnnotationsByType(Class<A> annotationClass) {
3595 Objects.requireNonNull(annotationClass);
3596
3597 AnnotationData annotationData = annotationData();
3598 return AnnotationSupport.getAssociatedAnnotations(annotationData.declaredAnnotations,
3599 this,
3600 annotationClass);
3601 }
3602
3603 /**
3604 * {@inheritDoc}
3605 * <p>Note that any annotations returned by this method are
3606 * declaration annotations.
3607 *
3608 * @since 1.5
3609 */
3610 @Override
3611 public Annotation[] getAnnotations() {
3612 return AnnotationParser.toArray(annotationData().annotations);
3613 }
3614
3615 /**
3616 * {@inheritDoc}
3617 * <p>Note that any annotation returned by this method is a
3618 * declaration annotation.
3619 *
3620 * @throws NullPointerException {@inheritDoc}
3621 * @since 1.8
3622 */
3623 @Override
3624 @SuppressWarnings("unchecked")
3625 public <A extends Annotation> A getDeclaredAnnotation(Class<A> annotationClass) {
3626 Objects.requireNonNull(annotationClass);
3627
3628 return (A) annotationData().declaredAnnotations.get(annotationClass);
3629 }
3630
3631 /**
3632 * {@inheritDoc}
3633 * <p>Note that any annotations returned by this method are
3634 * declaration annotations.
3635 *
3636 * @throws NullPointerException {@inheritDoc}
3637 * @since 1.8
3638 */
3639 @Override
3640 public <A extends Annotation> A[] getDeclaredAnnotationsByType(Class<A> annotationClass) {
3641 Objects.requireNonNull(annotationClass);
3642
3643 return AnnotationSupport.getDirectlyAndIndirectlyPresent(annotationData().declaredAnnotations,
3644 annotationClass);
3645 }
3646
3647 /**
3648 * {@inheritDoc}
3649 * <p>Note that any annotations returned by this method are
3650 * declaration annotations.
3651 *
3652 * @since 1.5
3653 */
3654 @Override
3655 public Annotation[] getDeclaredAnnotations() {
3656 return AnnotationParser.toArray(annotationData().declaredAnnotations);
3657 }
3658
3659 // annotation data that might get invalidated when JVM TI RedefineClasses() is called
3660 private static class AnnotationData {
3661 final Map<Class<? extends Annotation>, Annotation> annotations;
3662 final Map<Class<? extends Annotation>, Annotation> declaredAnnotations;
3663
3664 // Value of classRedefinedCount when we created this AnnotationData instance
3665 final int redefinedCount;
3666
3667 AnnotationData(Map<Class<? extends Annotation>, Annotation> annotations,
3668 Map<Class<? extends Annotation>, Annotation> declaredAnnotations,
3669 int redefinedCount) {
3670 this.annotations = annotations;
3671 this.declaredAnnotations = declaredAnnotations;
3672 this.redefinedCount = redefinedCount;
3673 }
3674 }
3675
3676 // Annotations cache
3677 @SuppressWarnings("UnusedDeclaration")
3678 private transient volatile AnnotationData annotationData;
3679
3680 private AnnotationData annotationData() {
3681 while (true) { // retry loop
3682 AnnotationData annotationData = this.annotationData;
3683 int classRedefinedCount = this.classRedefinedCount;
3684 if (annotationData != null &&
3685 annotationData.redefinedCount == classRedefinedCount) {
3686 return annotationData;
3687 }
3688 // null or stale annotationData -> optimistically create new instance
3689 AnnotationData newAnnotationData = createAnnotationData(classRedefinedCount);
3690 // try to install it
3691 if (Atomic.casAnnotationData(this, annotationData, newAnnotationData)) {
3692 // successfully installed new AnnotationData
3693 return newAnnotationData;
3694 }
3695 }
3696 }
3697
3698 private AnnotationData createAnnotationData(int classRedefinedCount) {
3699 Map<Class<? extends Annotation>, Annotation> declaredAnnotations =
3700 AnnotationParser.parseAnnotations(getRawAnnotations(), getConstantPool(), this);
3701 Class<?> superClass = getSuperclass();
3702 Map<Class<? extends Annotation>, Annotation> annotations = null;
3703 if (superClass != null) {
3704 Map<Class<? extends Annotation>, Annotation> superAnnotations =
3705 superClass.annotationData().annotations;
3706 for (Map.Entry<Class<? extends Annotation>, Annotation> e : superAnnotations.entrySet()) {
3707 Class<? extends Annotation> annotationClass = e.getKey();
3708 if (AnnotationType.getInstance(annotationClass).isInherited()) {
3709 if (annotations == null) { // lazy construction
3710 annotations = LinkedHashMap.newLinkedHashMap(Math.max(
3711 declaredAnnotations.size(),
3712 Math.min(12, declaredAnnotations.size() + superAnnotations.size())
3713 )
3714 );
3715 }
3716 annotations.put(annotationClass, e.getValue());
3717 }
3718 }
3719 }
3720 if (annotations == null) {
3721 // no inherited annotations -> share the Map with declaredAnnotations
3722 annotations = declaredAnnotations;
3723 } else {
3724 // at least one inherited annotation -> declared may override inherited
3725 annotations.putAll(declaredAnnotations);
3726 }
3727 return new AnnotationData(annotations, declaredAnnotations, classRedefinedCount);
3728 }
3729
3730 // Annotation interfaces cache their internal (AnnotationType) form
3731
3732 @SuppressWarnings("UnusedDeclaration")
3733 private transient volatile AnnotationType annotationType;
3734
3735 boolean casAnnotationType(AnnotationType oldType, AnnotationType newType) {
3736 return Atomic.casAnnotationType(this, oldType, newType);
3737 }
3738
3739 AnnotationType getAnnotationType() {
3740 return annotationType;
3741 }
3742
3743 Map<Class<? extends Annotation>, Annotation> getDeclaredAnnotationMap() {
3744 return annotationData().declaredAnnotations;
3745 }
3746
3747 /* Backing store of user-defined values pertaining to this class.
3748 * Maintained by the ClassValue class.
3749 */
3750 transient ClassValue.ClassValueMap classValueMap;
3751
3752 /**
3753 * Returns an {@code AnnotatedType} object that represents the use of a
3754 * type to specify the superclass of the entity represented by this {@code
3755 * Class} object. (The <em>use</em> of type Foo to specify the superclass
3756 * in '... extends Foo' is distinct from the <em>declaration</em> of class
3757 * Foo.)
3758 *
3759 * <p> If this {@code Class} object represents a class whose declaration
3760 * does not explicitly indicate an annotated superclass, then the return
3761 * value is an {@code AnnotatedType} object representing an element with no
3762 * annotations.
3763 *
3764 * <p> If this {@code Class} represents either the {@code Object} class, an
3765 * interface type, an array type, a primitive type, or void, the return
3766 * value is {@code null}.
3767 *
3768 * @return an object representing the superclass
3769 * @since 1.8
3770 */
3771 public AnnotatedType getAnnotatedSuperclass() {
3772 if (this == Object.class ||
3773 isInterface() ||
3774 isArray() ||
3775 isPrimitive() ||
3776 this == Void.TYPE) {
3777 return null;
3778 }
3779
3780 return TypeAnnotationParser.buildAnnotatedSuperclass(getRawTypeAnnotations(), getConstantPool(), this);
3781 }
3782
3783 /**
3784 * Returns an array of {@code AnnotatedType} objects that represent the use
3785 * of types to specify superinterfaces of the entity represented by this
3786 * {@code Class} object. (The <em>use</em> of type Foo to specify a
3787 * superinterface in '... implements Foo' is distinct from the
3788 * <em>declaration</em> of interface Foo.)
3789 *
3790 * <p> If this {@code Class} object represents a class, the return value is
3791 * an array containing objects representing the uses of interface types to
3792 * specify interfaces implemented by the class. The order of the objects in
3793 * the array corresponds to the order of the interface types used in the
3794 * 'implements' clause of the declaration of this {@code Class} object.
3795 *
3796 * <p> If this {@code Class} object represents an interface, the return
3797 * value is an array containing objects representing the uses of interface
3798 * types to specify interfaces directly extended by the interface. The
3799 * order of the objects in the array corresponds to the order of the
3800 * interface types used in the 'extends' clause of the declaration of this
3801 * {@code Class} object.
3802 *
3803 * <p> If this {@code Class} object represents a class or interface whose
3804 * declaration does not explicitly indicate any annotated superinterfaces,
3805 * the return value is an array of length 0.
3806 *
3807 * <p> If this {@code Class} object represents either the {@code Object}
3808 * class, an array type, a primitive type, or void, the return value is an
3809 * array of length 0.
3810 *
3811 * @return an array representing the superinterfaces
3812 * @since 1.8
3813 */
3814 public AnnotatedType[] getAnnotatedInterfaces() {
3815 return TypeAnnotationParser.buildAnnotatedInterfaces(getRawTypeAnnotations(), getConstantPool(), this);
3816 }
3817
3818 private native Class<?> getNestHost0();
3819
3820 /**
3821 * Returns the nest host of the <a href=#nest>nest</a> to which the class
3822 * or interface represented by this {@code Class} object belongs.
3823 * Every class and interface belongs to exactly one nest.
3824 *
3825 * If the nest host of this class or interface has previously
3826 * been determined, then this method returns the nest host.
3827 * If the nest host of this class or interface has
3828 * not previously been determined, then this method determines the nest
3829 * host using the algorithm of JVMS 5.4.4, and returns it.
3830 *
3831 * Often, a class or interface belongs to a nest consisting only of itself,
3832 * in which case this method returns {@code this} to indicate that the class
3833 * or interface is the nest host.
3834 *
3835 * <p>If this {@code Class} object represents a primitive type, an array type,
3836 * or {@code void}, then this method returns {@code this},
3837 * indicating that the represented entity belongs to the nest consisting only of
3838 * itself, and is the nest host.
3839 *
3840 * @return the nest host of this class or interface
3841 *
3842 * @since 11
3843 * @jvms 4.7.28 The {@code NestHost} Attribute
3844 * @jvms 4.7.29 The {@code NestMembers} Attribute
3845 * @jvms 5.4.4 Access Control
3846 */
3847 public Class<?> getNestHost() {
3848 if (isPrimitive() || isArray()) {
3849 return this;
3850 }
3851 return getNestHost0();
3852 }
3853
3854 /**
3855 * Determines if the given {@code Class} is a nestmate of the
3856 * class or interface represented by this {@code Class} object.
3857 * Two classes or interfaces are nestmates
3858 * if they have the same {@linkplain #getNestHost() nest host}.
3859 *
3860 * @param c the class to check
3861 * @return {@code true} if this class and {@code c} are members of
3862 * the same nest; and {@code false} otherwise.
3863 *
3864 * @since 11
3865 */
3866 public boolean isNestmateOf(Class<?> c) {
3867 if (this == c) {
3868 return true;
3869 }
3870 if (isPrimitive() || isArray() ||
3871 c.isPrimitive() || c.isArray()) {
3872 return false;
3873 }
3874
3875 return getNestHost() == c.getNestHost();
3876 }
3877
3878 private native Class<?>[] getNestMembers0();
3879
3880 /**
3881 * Returns an array containing {@code Class} objects representing all the
3882 * classes and interfaces that are members of the nest to which the class
3883 * or interface represented by this {@code Class} object belongs.
3884 *
3885 * First, this method obtains the {@linkplain #getNestHost() nest host},
3886 * {@code H}, of the nest to which the class or interface represented by
3887 * this {@code Class} object belongs. The zeroth element of the returned
3888 * array is {@code H}.
3889 *
3890 * Then, for each class or interface {@code C} which is recorded by {@code H}
3891 * as being a member of its nest, this method attempts to obtain the {@code Class}
3892 * object for {@code C} (using {@linkplain #getClassLoader() the defining class
3893 * loader} of the current {@code Class} object), and then obtains the
3894 * {@linkplain #getNestHost() nest host} of the nest to which {@code C} belongs.
3895 * The classes and interfaces which are recorded by {@code H} as being members
3896 * of its nest, and for which {@code H} can be determined as their nest host,
3897 * are indicated by subsequent elements of the returned array. The order of
3898 * such elements is unspecified. Duplicates are permitted.
3899 *
3900 * <p>If this {@code Class} object represents a primitive type, an array type,
3901 * or {@code void}, then this method returns a single-element array containing
3902 * {@code this}.
3903 *
3904 * @apiNote
3905 * The returned array includes only the nest members recorded in the {@code NestMembers}
3906 * attribute, and not any hidden classes that were added to the nest via
3907 * {@link MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
3908 * Lookup::defineHiddenClass}.
3909 *
3910 * @return an array of all classes and interfaces in the same nest as
3911 * this class or interface
3912 *
3913 * @since 11
3914 * @see #getNestHost()
3915 * @jvms 4.7.28 The {@code NestHost} Attribute
3916 * @jvms 4.7.29 The {@code NestMembers} Attribute
3917 */
3918 public Class<?>[] getNestMembers() {
3919 if (isPrimitive() || isArray()) {
3920 return new Class<?>[] { this };
3921 }
3922 Class<?>[] members = getNestMembers0();
3923 // Can't actually enable this due to bootstrapping issues
3924 // assert(members.length != 1 || members[0] == this); // expected invariant from VM
3925 return members;
3926 }
3927
3928 /**
3929 * Returns the descriptor string of the entity (class, interface, array class,
3930 * primitive type, or {@code void}) represented by this {@code Class} object.
3931 *
3932 * <p> If this {@code Class} object represents a class or interface,
3933 * not an array class, then:
3934 * <ul>
3935 * <li> If the class or interface is not {@linkplain Class#isHidden() hidden},
3936 * then the result is a field descriptor (JVMS {@jvms 4.3.2})
3937 * for the class or interface. Calling
3938 * {@link ClassDesc#ofDescriptor(String) ClassDesc::ofDescriptor}
3939 * with the result descriptor string produces a {@link ClassDesc ClassDesc}
3940 * describing this class or interface.
3941 * <li> If the class or interface is {@linkplain Class#isHidden() hidden},
3942 * then the result is a string of the form:
3943 * <blockquote>
3944 * {@code "L" +} <em>N</em> {@code + "." + <suffix> + ";"}
3945 * </blockquote>
3946 * where <em>N</em> is the {@linkplain ClassLoader##binary-name binary name}
3947 * encoded in internal form indicated by the {@code class} file passed to
3948 * {@link MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
3949 * Lookup::defineHiddenClass}, and {@code <suffix>} is an unqualified name.
3950 * A hidden class or interface has no {@linkplain ClassDesc nominal descriptor}.
3951 * The result string is not a type descriptor.
3952 * </ul>
3953 *
3954 * <p> If this {@code Class} object represents an array class, then
3955 * the result is a string consisting of one or more '{@code [}' characters
3956 * representing the depth of the array nesting, followed by the
3957 * descriptor string of the element type.
3958 * <ul>
3959 * <li> If the element type is not a {@linkplain Class#isHidden() hidden} class
3960 * or interface, then this array class can be described nominally.
3961 * Calling {@link ClassDesc#ofDescriptor(String) ClassDesc::ofDescriptor}
3962 * with the result descriptor string produces a {@link ClassDesc ClassDesc}
3963 * describing this array class.
3964 * <li> If the element type is a {@linkplain Class#isHidden() hidden} class or
3965 * interface, then this array class cannot be described nominally.
3966 * The result string is not a type descriptor.
3967 * </ul>
3968 *
3969 * <p> If this {@code Class} object represents a primitive type or
3970 * {@code void}, then the result is a field descriptor string which
3971 * is a one-letter code corresponding to a primitive type or {@code void}
3972 * ({@code "B", "C", "D", "F", "I", "J", "S", "Z", "V"}) (JVMS {@jvms 4.3.2}).
3973 *
3974 * @return the descriptor string for this {@code Class} object
3975 * @jvms 4.3.2 Field Descriptors
3976 * @since 12
3977 */
3978 @Override
3979 public String descriptorString() {
3980 if (isPrimitive())
3981 return Wrapper.forPrimitiveType(this).basicTypeString();
3982
3983 if (isArray()) {
3984 return "[".concat(componentType.descriptorString());
3985 } else if (isHidden()) {
3986 String name = getName();
3987 int index = name.indexOf('/');
3988 return new StringBuilder(name.length() + 2)
3989 .append('L')
3990 .append(name.substring(0, index).replace('.', '/'))
3991 .append('.')
3992 .append(name, index + 1, name.length())
3993 .append(';')
3994 .toString();
3995 } else {
3996 String name = getName().replace('.', '/');
3997 return StringConcatHelper.concat("L", name, ";");
3998 }
3999 }
4000
4001 /**
4002 * Returns the component type of this {@code Class}, if it describes
4003 * an array type, or {@code null} otherwise.
4004 *
4005 * @implSpec
4006 * Equivalent to {@link Class#getComponentType()}.
4007 *
4008 * @return a {@code Class} describing the component type, or {@code null}
4009 * if this {@code Class} does not describe an array type
4010 * @since 12
4011 */
4012 @Override
4013 public Class<?> componentType() {
4014 return getComponentType();
4015 }
4016
4017 /**
4018 * Returns a {@code Class} for an array type whose component type
4019 * is described by this {@linkplain Class}.
4020 *
4021 * @throws UnsupportedOperationException if this component type is {@linkplain
4022 * Void#TYPE void} or if the number of dimensions of the resulting array
4023 * type would exceed 255.
4024 * @return a {@code Class} describing the array type
4025 * @jvms 4.3.2 Field Descriptors
4026 * @jvms 4.4.1 The {@code CONSTANT_Class_info} Structure
4027 * @since 12
4028 */
4029 @Override
4030 public Class<?> arrayType() {
4031 try {
4032 return Array.newInstance(this, 0).getClass();
4033 } catch (IllegalArgumentException iae) {
4034 throw new UnsupportedOperationException(iae);
4035 }
4036 }
4037
4038 /**
4039 * Returns a nominal descriptor for this instance, if one can be
4040 * constructed, or an empty {@link Optional} if one cannot be.
4041 *
4042 * @return An {@link Optional} containing the resulting nominal descriptor,
4043 * or an empty {@link Optional} if one cannot be constructed.
4044 * @since 12
4045 */
4046 @Override
4047 public Optional<ClassDesc> describeConstable() {
4048 Class<?> c = isArray() ? elementType() : this;
4049 return c.isHidden() ? Optional.empty()
4050 : Optional.of(ConstantUtils.classDesc(this));
4051 }
4052
4053 /**
4054 * Returns {@code true} if and only if the underlying class is a hidden class.
4055 *
4056 * @return {@code true} if and only if this class is a hidden class.
4057 *
4058 * @since 15
4059 * @see MethodHandles.Lookup#defineHiddenClass
4060 * @see Class##hiddenClasses Hidden Classes
4061 */
4062 @IntrinsicCandidate
4063 public native boolean isHidden();
4064
4065 /**
4066 * Returns an array containing {@code Class} objects representing the
4067 * direct subinterfaces or subclasses permitted to extend or
4068 * implement this class or interface if it is sealed. The order of such elements
4069 * is unspecified. The array is empty if this sealed class or interface has no
4070 * permitted subclass. If this {@code Class} object represents a primitive type,
4071 * {@code void}, an array type, or a class or interface that is not sealed,
4072 * that is {@link #isSealed()} returns {@code false}, then this method returns {@code null}.
4073 * Conversely, if {@link #isSealed()} returns {@code true}, then this method
4074 * returns a non-null value.
4075 *
4076 * For each class or interface {@code C} which is recorded as a permitted
4077 * direct subinterface or subclass of this class or interface,
4078 * this method attempts to obtain the {@code Class}
4079 * object for {@code C} (using {@linkplain #getClassLoader() the defining class
4080 * loader} of the current {@code Class} object).
4081 * The {@code Class} objects which can be obtained and which are direct
4082 * subinterfaces or subclasses of this class or interface,
4083 * are indicated by elements of the returned array. If a {@code Class} object
4084 * cannot be obtained, it is silently ignored, and not included in the result
4085 * array.
4086 *
4087 * @return an array of {@code Class} objects of the permitted subclasses of this class
4088 * or interface, or {@code null} if this class or interface is not sealed.
4089 *
4090 * @jls 8.1 Class Declarations
4091 * @jls 9.1 Interface Declarations
4092 * @since 17
4093 */
4094 public Class<?>[] getPermittedSubclasses() {
4095 Class<?>[] subClasses;
4096 if (isArray() || isPrimitive() || (subClasses = getPermittedSubclasses0()) == null) {
4097 return null;
4098 }
4099 if (subClasses.length > 0) {
4100 if (Arrays.stream(subClasses).anyMatch(c -> !isDirectSubType(c))) {
4101 subClasses = Arrays.stream(subClasses)
4102 .filter(this::isDirectSubType)
4103 .toArray(s -> new Class<?>[s]);
4104 }
4105 }
4106 return subClasses;
4107 }
4108
4109 private boolean isDirectSubType(Class<?> c) {
4110 if (isInterface()) {
4111 for (Class<?> i : c.getInterfaces(/* cloneArray */ false)) {
4112 if (i == this) {
4113 return true;
4114 }
4115 }
4116 } else {
4117 return c.getSuperclass() == this;
4118 }
4119 return false;
4120 }
4121
4122 /**
4123 * Returns {@code true} if and only if this {@code Class} object represents
4124 * a sealed class or interface. If this {@code Class} object represents a
4125 * primitive type, {@code void}, or an array type, this method returns
4126 * {@code false}. A sealed class or interface has (possibly zero) permitted
4127 * subclasses; {@link #getPermittedSubclasses()} returns a non-null but
4128 * possibly empty value for a sealed class or interface.
4129 *
4130 * @return {@code true} if and only if this {@code Class} object represents
4131 * a sealed class or interface.
4132 *
4133 * @jls 8.1 Class Declarations
4134 * @jls 9.1 Interface Declarations
4135 * @since 17
4136 */
4137 public boolean isSealed() {
4138 if (isArray() || isPrimitive()) {
4139 return false;
4140 }
4141 return getPermittedSubclasses() != null;
4142 }
4143
4144 private native Class<?>[] getPermittedSubclasses0();
4145
4146 /*
4147 * Return the class's major and minor class file version packed into an int.
4148 * The high order 16 bits contain the class's minor version. The low order
4149 * 16 bits contain the class's major version.
4150 *
4151 * If the class is an array type then the class file version of its element
4152 * type is returned. If the class is a primitive type then the latest class
4153 * file major version is returned and zero is returned for the minor version.
4154 */
4155 int getClassFileVersion() {
4156 Class<?> c = isArray() ? elementType() : this;
4157 return c.getClassFileVersion0();
4158 }
4159
4160 private native int getClassFileVersion0();
4161
4162 /**
4163 * Return the access flags as they were in the class's bytecode, including
4164 * the original setting of ACC_SUPER.
4165 *
4166 * If this {@code Class} object represents a primitive type or
4167 * void, the flags are {@code PUBLIC}, {@code ABSTRACT}, and
4168 * {@code FINAL}.
4169 * If this {@code Class} object represents an array type, return 0.
4170 */
4171 int getClassFileAccessFlags() {
4172 return classFileAccessFlags;
4173 }
4174
4175 // Support for "OLD" CDS workflow -- {
4176 private static final int RD_PUBLIC_METHODS = (1 << 0);
4177 private static final int RD_PUBLIC_FIELDS = (1 << 1);
4178 private static final int RD_DECLARED_CTORS = (1 << 2);
4179 private static final int RD_PUBLIC_CTORS = (1 << 3);
4180 private static final int RD_DECLARED_METHODS = (1 << 4);
4181 private static final int RD_DECLARED_PUBLIC_METHODS = (1 << 5);
4182 private static final int RD_DECLARED_FIELDS = (1 << 6);
4183 private static final int RD_DECLARED_PUBLIC_FIELDS = (1 << 7);
4184 private static final int RD_DECLARED_INTERFACES = (1 << 8);
4185 private static final int RD_DECLARED_SIMPLE_NAME = (1 << 9);
4186 private static final int RD_DECLARED_CANONICAL_NAME = (1 << 10);
4187 private static final int CLS_NAME = (1 << 10);
4188
4189
4190 private int encodeReflectionData() {
4191 int flags = CLS_NAME;
4192 if (reflectionData != null) {
4193 flags = (reflectionData.publicMethods != null ? RD_PUBLIC_METHODS : 0) |
4194 (reflectionData.publicFields != null ? RD_PUBLIC_FIELDS : 0) |
4195 (reflectionData.declaredConstructors != null ? RD_DECLARED_CTORS : 0) |
4196 (reflectionData.publicConstructors != null ? RD_PUBLIC_CTORS : 0) |
4197 (reflectionData.declaredMethods != null ? RD_DECLARED_METHODS : 0) |
4198 (reflectionData.declaredPublicMethods != null ? RD_DECLARED_PUBLIC_METHODS : 0) |
4199 (reflectionData.declaredFields != null ? RD_DECLARED_FIELDS : 0) |
4200 (reflectionData.declaredPublicFields != null ? RD_DECLARED_PUBLIC_FIELDS : 0) |
4201 (reflectionData.interfaces != null ? RD_DECLARED_INTERFACES : 0) |
4202 (reflectionData.simpleName != null ? RD_DECLARED_SIMPLE_NAME : 0) |
4203 (reflectionData.canonicalName != null ? RD_DECLARED_CANONICAL_NAME : 0);
4204 }
4205 return flags;
4206 }
4207 private void generateReflectionData(int flags) {
4208 if ((flags & CLS_NAME ) != 0) { getName(); } // String name
4209 if ((flags & RD_PUBLIC_METHODS ) != 0) { privateGetPublicMethods(); } // Method[] publicMethods;
4210 if ((flags & RD_PUBLIC_FIELDS ) != 0) { privateGetPublicFields(); } // Field[] publicFields;
4211 if ((flags & RD_DECLARED_CTORS ) != 0) { privateGetDeclaredConstructors(false); } // Constructor<T>[] declaredConstructors;
4212 if ((flags & RD_PUBLIC_CTORS ) != 0) { privateGetDeclaredConstructors(true); } // Constructor<T>[] publicConstructors;
4213 if ((flags & RD_DECLARED_METHODS ) != 0) { privateGetDeclaredMethods(false); } // Method[] declaredMethods;
4214 if ((flags & RD_DECLARED_PUBLIC_METHODS) != 0) { privateGetDeclaredMethods(true); } // Method[] declaredPublicMethods;
4215 if ((flags & RD_DECLARED_FIELDS ) != 0) { privateGetDeclaredFields(false); } // Field[] declaredFields;
4216 if ((flags & RD_DECLARED_PUBLIC_FIELDS ) != 0) { privateGetDeclaredFields(true); } // Field[] declaredPublicFields;
4217 if ((flags & RD_DECLARED_INTERFACES ) != 0) { getInterfaces(false); } // Class<?>[] interfaces;
4218 if ((flags & RD_DECLARED_SIMPLE_NAME ) != 0) { getSimpleName(); } // String simpleName;
4219 if ((flags & RD_DECLARED_CANONICAL_NAME) != 0) { getCanonicalName(); } // String canonicalName;
4220 }
4221
4222 // -- }
4223 }