1 /*
2 * Copyright (c) 1994, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package java.lang;
27
28 import java.lang.annotation.Annotation;
29 import java.lang.constant.ClassDesc;
30 import java.lang.constant.ConstantDescs;
31 import java.lang.invoke.TypeDescriptor;
32 import java.lang.invoke.MethodHandles;
33 import java.lang.ref.SoftReference;
34 import java.io.IOException;
35 import java.io.InputStream;
36 import java.io.ObjectStreamField;
37 import java.lang.reflect.AnnotatedElement;
38 import java.lang.reflect.AnnotatedType;
39 import java.lang.reflect.AccessFlag;
40 import java.lang.reflect.Array;
41 import java.lang.reflect.ClassFileFormatVersion;
42 import java.lang.reflect.Constructor;
43 import java.lang.reflect.Executable;
44 import java.lang.reflect.Field;
45 import java.lang.reflect.GenericArrayType;
46 import java.lang.reflect.GenericDeclaration;
47 import java.lang.reflect.InvocationTargetException;
48 import java.lang.reflect.Member;
49 import java.lang.reflect.Method;
50 import java.lang.reflect.Modifier;
51 import java.lang.reflect.RecordComponent;
52 import java.lang.reflect.Type;
53 import java.lang.reflect.TypeVariable;
54 import java.lang.constant.Constable;
55 import java.net.URL;
56 import java.security.AllPermission;
57 import java.security.Permissions;
58 import java.security.ProtectionDomain;
59 import java.util.ArrayList;
60 import java.util.Arrays;
61 import java.util.Collection;
62 import java.util.HashMap;
63 import java.util.HashSet;
64 import java.util.LinkedHashMap;
65 import java.util.LinkedHashSet;
66 import java.util.List;
67 import java.util.Map;
68 import java.util.Objects;
69 import java.util.Optional;
70 import java.util.Set;
71 import java.util.stream.Collectors;
72
73 import jdk.internal.constant.ConstantUtils;
74 import jdk.internal.javac.PreviewFeature;
75 import jdk.internal.loader.BootLoader;
76 import jdk.internal.loader.BuiltinClassLoader;
77 import jdk.internal.misc.PreviewFeatures;
78 import jdk.internal.misc.Unsafe;
79 import jdk.internal.module.Resources;
80 import jdk.internal.reflect.CallerSensitive;
81 import jdk.internal.reflect.CallerSensitiveAdapter;
82 import jdk.internal.reflect.ConstantPool;
83 import jdk.internal.reflect.Reflection;
84 import jdk.internal.reflect.ReflectionFactory;
85 import jdk.internal.util.ModifiedUtf;
86 import jdk.internal.vm.annotation.AOTRuntimeSetup;
87 import jdk.internal.vm.annotation.AOTSafeClassInitializer;
88 import jdk.internal.vm.annotation.IntrinsicCandidate;
89 import jdk.internal.vm.annotation.Stable;
90
91 import sun.invoke.util.BytecodeDescriptor;
92 import sun.invoke.util.Wrapper;
93 import sun.reflect.generics.factory.CoreReflectionFactory;
94 import sun.reflect.generics.factory.GenericsFactory;
95 import sun.reflect.generics.repository.ClassRepository;
96 import sun.reflect.generics.scope.ClassScope;
97 import sun.reflect.annotation.*;
98
99 /**
100 * Instances of the class {@code Class} represent classes and
101 * interfaces in a running Java application. An enum class and a record
102 * class are kinds of class; an annotation interface is a kind of
103 * interface. Every array also belongs to a class that is reflected as
104 * a {@code Class} object that is shared by all arrays with the same
105 * element type and number of dimensions. The primitive Java types
106 * ({@code boolean}, {@code byte}, {@code char}, {@code short}, {@code
107 * int}, {@code long}, {@code float}, and {@code double}), and the
108 * keyword {@code void} are also represented as {@code Class} objects.
109 *
110 * <p> {@code Class} has no public constructor. Instead a {@code Class}
111 * object is constructed automatically by the Java Virtual Machine when
112 * a class is derived from the bytes of a {@code class} file through
113 * the invocation of one of the following methods:
114 * <ul>
115 * <li> {@link ClassLoader#defineClass(String, byte[], int, int) ClassLoader::defineClass}
116 * <li> {@link java.lang.invoke.MethodHandles.Lookup#defineClass(byte[])
117 * java.lang.invoke.MethodHandles.Lookup::defineClass}
118 * <li> {@link java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
119 * java.lang.invoke.MethodHandles.Lookup::defineHiddenClass}
120 * </ul>
121 *
122 * <p> The methods of class {@code Class} expose many characteristics of a
123 * class or interface. Most characteristics are derived from the {@code class}
124 * file that the class loader passed to the Java Virtual Machine or
125 * from the {@code class} file passed to {@code Lookup::defineClass}
126 * or {@code Lookup::defineHiddenClass}.
127 * A few characteristics are determined by the class loading environment
128 * at run time, such as the module returned by {@link #getModule() getModule()}.
129 *
130 * <p> The following example uses a {@code Class} object to print the
131 * class name of an object:
132 *
133 * {@snippet lang="java" :
134 * void printClassName(Object obj) {
135 * System.out.println("The class of " + obj +
136 * " is " + obj.getClass().getName());
137 * }}
138 *
139 * It is also possible to get the {@code Class} object for a named
140 * class or interface (or for {@code void}) using a <dfn>class literal</dfn>
141 * (JLS {@jls 15.8.2}).
142 * For example:
143 *
144 * {@snippet lang="java" :
145 * System.out.println("The name of class Foo is: " + Foo.class.getName()); // @highlight substring="Foo.class"
146 * }
147 *
148 * <p> Some methods of class {@code Class} expose whether the declaration of
149 * a class or interface in Java source code was <em>enclosed</em> within
150 * another declaration. Other methods describe how a class or interface
151 * is situated in a <dfn>{@index "nest"}</dfn>. A nest is a set of
152 * classes and interfaces, in the same run-time package, that
153 * allow mutual access to their {@code private} members.
154 * The classes and interfaces are known as <dfn>{@index "nestmates"}</dfn>
155 * (JVMS {@jvms 4.7.29}).
156 * One nestmate acts as the
157 * <dfn>nest host</dfn> (JVMS {@jvms 4.7.28}), and enumerates the other nestmates which
158 * belong to the nest; each of them in turn records it as the nest host.
159 * The classes and interfaces which belong to a nest, including its host, are
160 * determined when
161 * {@code class} files are generated, for example, a Java compiler
162 * will typically record a top-level class as the host of a nest where the
163 * other members are the classes and interfaces whose declarations are
164 * enclosed within the top-level class declaration.
165 *
166 * <h2><a id=hiddenClasses>Hidden Classes</a></h2>
167 * A class or interface created by the invocation of
168 * {@link java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
169 * Lookup::defineHiddenClass} is a {@linkplain Class#isHidden() <dfn>hidden</dfn>}
170 * class or interface.
171 * All kinds of class, including enum classes and record classes, may be
172 * hidden classes; all kinds of interface, including annotation interfaces,
173 * may be hidden interfaces.
174 *
175 * The {@linkplain #getName() name of a hidden class or interface} is
176 * not a {@linkplain ClassLoader##binary-name binary name},
177 * which means the following:
178 * <ul>
179 * <li>A hidden class or interface cannot be referenced by the constant pools
180 * of other classes and interfaces.
181 * <li>A hidden class or interface cannot be described in
182 * {@linkplain java.lang.constant.ConstantDesc <em>nominal form</em>} by
183 * {@link #describeConstable() Class::describeConstable},
184 * {@link ClassDesc#of(String) ClassDesc::of}, or
185 * {@link ClassDesc#ofDescriptor(String) ClassDesc::ofDescriptor}.
186 * <li>A hidden class or interface cannot be discovered by {@link #forName Class::forName}
187 * or {@link ClassLoader#loadClass(String, boolean) ClassLoader::loadClass}.
188 * </ul>
189 *
190 * A hidden class or interface is never an array class, but may be
191 * the element type of an array. In all other respects, the fact that
192 * a class or interface is hidden has no bearing on the characteristics
193 * exposed by the methods of class {@code Class}.
194 *
195 * <h2><a id=implicitClasses>Implicitly Declared Classes</a></h2>
196 *
197 * Conventionally, a Java compiler, starting from a source file for an
198 * implicitly declared class, say {@code HelloWorld.java}, creates a
199 * similarly-named {@code class} file, {@code HelloWorld.class}, where
200 * the class stored in that {@code class} file is named {@code
201 * "HelloWorld"}, matching the base names of the source and {@code
202 * class} files.
203 *
204 * For the {@code Class} object of an implicitly declared class {@code
205 * HelloWorld}, the methods to get the {@linkplain #getName name} and
206 * {@linkplain #getTypeName type name} return results
207 * equal to {@code "HelloWorld"}. The {@linkplain #getSimpleName
208 * simple name} of such an implicitly declared class is {@code "HelloWorld"} and
209 * the {@linkplain #getCanonicalName canonical name} is {@code "HelloWorld"}.
210 *
211 * @param <T> the type of the class modeled by this {@code Class}
212 * object. For example, the type of {@code String.class} is {@code
213 * Class<String>}. Use {@code Class<?>} if the class being modeled is
214 * unknown.
215 *
216 * @see java.lang.ClassLoader#defineClass(byte[], int, int)
217 * @since 1.0
218 */
219 @AOTSafeClassInitializer
220 public final class Class<T> implements java.io.Serializable,
221 GenericDeclaration,
222 Type,
223 AnnotatedElement,
224 TypeDescriptor.OfField<Class<?>>,
225 Constable {
226 private static final int ANNOTATION = 0x00002000;
227 private static final int ENUM = 0x00004000;
228 private static final int SYNTHETIC = 0x00001000;
229
230 private static native void registerNatives();
231 static {
232 runtimeSetup();
233 }
234
235 /// No significant static final fields; [#resetArchivedStates()] handles
236 /// prevents storing [#reflectionFactory] into AOT image.
237 @AOTRuntimeSetup
238 private static void runtimeSetup() {
239 registerNatives();
240 }
241
242 /*
243 * Private constructor. Only the Java Virtual Machine creates Class objects.
244 * This constructor is not used and prevents the default constructor being
245 * generated.
246 */
247 private Class(ClassLoader loader, Class<?> arrayComponentType, char mods, ProtectionDomain pd, boolean isPrim, char flags) {
248 // Initialize final field for classLoader. The initialization value of non-null
249 // prevents future JIT optimizations from assuming this final field is null.
250 // The following assignments are done directly by the VM without calling this constructor.
251 classLoader = loader;
252 componentType = arrayComponentType;
253 modifiers = mods;
254 protectionDomain = pd;
255 primitive = isPrim;
256 classFileAccessFlags = flags;
257 }
258
259 /**
260 * Converts the object to a string. The string representation is the
261 * string "class" or "interface", followed by a space, and then by the
262 * name of the class in the format returned by {@code getName}.
263 * If this {@code Class} object represents a primitive type,
264 * this method returns the name of the primitive type. If
265 * this {@code Class} object represents void this method returns
266 * "void". If this {@code Class} object represents an array type,
267 * this method returns "class " followed by {@code getName}.
268 *
269 * @return a string representation of this {@code Class} object.
270 */
271 public String toString() {
272 String kind = isInterface() ? "interface " : isPrimitive() ? "" : "class ";
273 return kind.concat(getName());
274 }
275
276 /**
277 * Returns a string describing this {@code Class}, including
278 * information about modifiers, {@link #isSealed() sealed}/{@code
279 * non-sealed} status, and type parameters.
280 *
281 * The string is formatted as a list of type modifiers, if any,
282 * followed by the kind of type (empty string for primitive types
283 * and {@code class}, {@code enum}, {@code interface},
284 * {@code @interface}, or {@code record} as appropriate), followed
285 * by the type's name, followed by an angle-bracketed
286 * comma-separated list of the type's type parameters, if any,
287 * including informative bounds on the type parameters, if any.
288 *
289 * A space is used to separate modifiers from one another and to
290 * separate any modifiers from the kind of type. The modifiers
291 * occur in canonical order. If there are no type parameters, the
292 * type parameter list is elided.
293 *
294 * For an array type, the string starts with the type name,
295 * followed by an angle-bracketed comma-separated list of the
296 * type's type parameters, if any, followed by a sequence of
297 * {@code []} characters, one set of brackets per dimension of
298 * the array.
299 *
300 * <p>Note that since information about the runtime representation
301 * of a type is being generated, modifiers not present on the
302 * originating source code or illegal on the originating source
303 * code may be present.
304 *
305 * @return a string describing this {@code Class}, including
306 * information about modifiers and type parameters
307 *
308 * @since 1.8
309 */
310 public String toGenericString() {
311 if (isPrimitive()) {
312 return toString();
313 } else {
314 StringBuilder sb = new StringBuilder();
315 Class<?> component = this;
316 int arrayDepth = 0;
317
318 if (isArray()) {
319 do {
320 arrayDepth++;
321 component = component.getComponentType();
322 } while (component.isArray());
323 sb.append(component.getName());
324 } else {
325 // Class modifiers are a superset of interface modifiers
326 int modifiers = getModifiers() & Modifier.classModifiers();
327 // Modifier.toString() below mis-interprets SYNCHRONIZED, STRICT, and VOLATILE bits
328 modifiers &= ~(Modifier.SYNCHRONIZED | Modifier.STRICT | Modifier.VOLATILE);
329 if (modifiers != 0) {
330 sb.append(Modifier.toString(modifiers));
331 sb.append(' ');
332 }
333
334 // A class cannot be strictfp and sealed/non-sealed so
335 // it is sufficient to check for sealed-ness after all
336 // modifiers are printed.
337 addSealingInfo(modifiers, sb);
338
339 if (isAnnotation()) {
340 sb.append('@');
341 }
342 if (isInterface()) { // Note: all annotation interfaces are interfaces
343 sb.append("interface");
344 } else {
345 if (isEnum())
346 sb.append("enum");
347 else {
348 if (isValue()) {
349 sb.append("value ");
350 }
351 if (isRecord())
352 sb.append("record");
353 else
354 sb.append("class");
355 }
356 }
357 sb.append(' ');
358 sb.append(getName());
359 }
360
361 TypeVariable<?>[] typeparms = component.getTypeParameters();
362 if (typeparms.length > 0) {
363 sb.append(Arrays.stream(typeparms)
364 .map(Class::typeVarBounds)
365 .collect(Collectors.joining(",", "<", ">")));
366 }
367
368 if (arrayDepth > 0) sb.append("[]".repeat(arrayDepth));
369
370 return sb.toString();
371 }
372 }
373
374 private void addSealingInfo(int modifiers, StringBuilder sb) {
375 // A class can be final XOR sealed XOR non-sealed.
376 if (Modifier.isFinal(modifiers)) {
377 return; // no-op
378 } else {
379 if (isSealed()) {
380 sb.append("sealed ");
381 return;
382 } else {
383 // Check for sealed ancestor, which implies this class
384 // is non-sealed.
385 if (hasSealedAncestor(this)) {
386 sb.append("non-sealed ");
387 }
388 }
389 }
390 }
391
392 private boolean hasSealedAncestor(Class<?> clazz) {
393 // From JLS 8.1.1.2:
394 // "It is a compile-time error if a class has a sealed direct
395 // superclass or a sealed direct superinterface, and is not
396 // declared final, sealed, or non-sealed either explicitly or
397 // implicitly.
398 // Thus, an effect of the sealed keyword is to force all
399 // direct subclasses to explicitly declare whether they are
400 // final, sealed, or non-sealed. This avoids accidentally
401 // exposing a sealed class hierarchy to unwanted subclassing."
402
403 // Therefore, will just check direct superclass and
404 // superinterfaces.
405 var superclass = clazz.getSuperclass();
406 if (superclass != null && superclass.isSealed()) {
407 return true;
408 }
409 for (var superinterface : clazz.getInterfaces()) {
410 if (superinterface.isSealed()) {
411 return true;
412 }
413 }
414 return false;
415 }
416
417 static String typeVarBounds(TypeVariable<?> typeVar) {
418 Type[] bounds = typeVar.getBounds();
419 if (bounds.length == 1 && bounds[0].equals(Object.class)) {
420 return typeVar.getName();
421 } else {
422 return typeVar.getName() + " extends " +
423 Arrays.stream(bounds)
424 .map(Type::getTypeName)
425 .collect(Collectors.joining(" & "));
426 }
427 }
428
429 /**
430 * Returns the {@code Class} object associated with the class or
431 * interface with the given string name. Invoking this method is
432 * equivalent to:
433 *
434 * {@snippet lang="java" :
435 * Class.forName(className, true, currentLoader)
436 * }
437 *
438 * where {@code currentLoader} denotes the defining class loader of
439 * the current class.
440 *
441 * <p> For example, the following code fragment returns the
442 * runtime {@code Class} object for the class named
443 * {@code java.lang.Thread}:
444 *
445 * {@snippet lang="java" :
446 * Class<?> t = Class.forName("java.lang.Thread");
447 * }
448 * <p>
449 * A call to {@code forName("X")} causes the class named
450 * {@code X} to be initialized.
451 *
452 * <p>
453 * In cases where this method is called from a context where there is no
454 * caller frame on the stack (e.g. when called directly from a JNI
455 * attached thread), the system class loader is used.
456 *
457 * @param className the {@linkplain ClassLoader##binary-name binary name}
458 * of the class or the string representing an array type
459 * @return the {@code Class} object for the class with the
460 * specified name.
461 * @throws LinkageError if the linkage fails
462 * @throws ExceptionInInitializerError if the initialization provoked
463 * by this method fails
464 * @throws ClassNotFoundException if the class cannot be located
465 *
466 * @jls 12.2 Loading of Classes and Interfaces
467 * @jls 12.3 Linking of Classes and Interfaces
468 * @jls 12.4 Initialization of Classes and Interfaces
469 */
470 @CallerSensitive
471 public static Class<?> forName(String className)
472 throws ClassNotFoundException {
473 Class<?> caller = Reflection.getCallerClass();
474 return forName(className, caller);
475 }
476
477 // Caller-sensitive adapter method for reflective invocation
478 @CallerSensitiveAdapter
479 private static Class<?> forName(String className, Class<?> caller)
480 throws ClassNotFoundException {
481 validateClassNameLength(className);
482 ClassLoader loader = (caller == null) ? ClassLoader.getSystemClassLoader()
483 : ClassLoader.getClassLoader(caller);
484 return forName0(className, true, loader);
485 }
486
487 /**
488 * Returns the {@code Class} object associated with the class or
489 * interface with the given string name, using the given class loader.
490 * Given the {@linkplain ClassLoader##binary-name binary name} for a class or interface,
491 * this method attempts to locate and load the class or interface. The specified
492 * class loader is used to load the class or interface. If the parameter
493 * {@code loader} is {@code null}, the class is loaded through the bootstrap
494 * class loader. The class is initialized only if the
495 * {@code initialize} parameter is {@code true} and if it has
496 * not been initialized earlier.
497 *
498 * <p> This method cannot be used to obtain any of the {@code Class} objects
499 * representing primitive types or void, hidden classes or interfaces,
500 * or array classes whose element type is a hidden class or interface.
501 * If {@code name} denotes a primitive type or void, for example {@code I},
502 * an attempt will be made to locate a user-defined class in the unnamed package
503 * whose name is {@code I} instead.
504 * To obtain a {@code Class} object for a named primitive type
505 * such as {@code int} or {@code long} use {@link
506 * #forPrimitiveName(String)}.
507 *
508 * <p> To obtain the {@code Class} object associated with an array class,
509 * the name consists of one or more {@code '['} representing the depth
510 * of the array nesting, followed by the element type as encoded in
511 * {@linkplain ##nameFormat the table} specified in {@code Class.getName()}.
512 *
513 * <p> Examples:
514 * {@snippet lang="java" :
515 * Class<?> threadClass = Class.forName("java.lang.Thread", false, currentLoader);
516 * Class<?> stringArrayClass = Class.forName("[Ljava.lang.String;", false, currentLoader);
517 * Class<?> intArrayClass = Class.forName("[[[I", false, currentLoader); // Class of int[][][]
518 * Class<?> nestedClass = Class.forName("java.lang.Character$UnicodeBlock", false, currentLoader);
519 * Class<?> fooClass = Class.forName("Foo", true, currentLoader);
520 * }
521 *
522 * <p> A call to {@code getName()} on the {@code Class} object returned
523 * from {@code forName(}<i>N</i>{@code )} returns <i>N</i>.
524 *
525 * <p> A call to {@code forName("[L}<i>N</i>{@code ;")} causes the element type
526 * named <i>N</i> to be loaded but not initialized regardless of the value
527 * of the {@code initialize} parameter.
528 *
529 * @apiNote
530 * This method throws errors related to loading, linking or initializing
531 * as specified in Sections {@jls 12.2}, {@jls 12.3}, and {@jls 12.4} of
532 * <cite>The Java Language Specification</cite>.
533 * In addition, this method does not check whether the requested class
534 * is accessible to its caller.
535 *
536 * @param name the {@linkplain ClassLoader##binary-name binary name}
537 * of the class or the string representing an array class
538 *
539 * @param initialize if {@code true} the class will be initialized
540 * (which implies linking). See Section {@jls
541 * 12.4} of <cite>The Java Language
542 * Specification</cite>.
543 * @param loader class loader from which the class must be loaded
544 * @return class object representing the desired class
545 *
546 * @throws LinkageError if the linkage fails
547 * @throws ExceptionInInitializerError if the initialization provoked
548 * by this method fails
549 * @throws ClassNotFoundException if the class cannot be located by
550 * the specified class loader
551 *
552 * @see java.lang.Class#forName(String)
553 * @see java.lang.ClassLoader
554 *
555 * @jls 12.2 Loading of Classes and Interfaces
556 * @jls 12.3 Linking of Classes and Interfaces
557 * @jls 12.4 Initialization of Classes and Interfaces
558 * @jls 13.1 The Form of a Binary
559 * @since 1.2
560 */
561 public static Class<?> forName(String name, boolean initialize, ClassLoader loader)
562 throws ClassNotFoundException
563 {
564 validateClassNameLength(name);
565 return forName0(name, initialize, loader);
566 }
567
568 /** Called after security check for system loader access checks have been made. */
569 private static native Class<?> forName0(String name, boolean initialize,
570 ClassLoader loader)
571 throws ClassNotFoundException;
572
573
574 /**
575 * Returns the {@code Class} with the given {@linkplain ClassLoader##binary-name
576 * binary name} in the given module.
577 *
578 * <p> This method attempts to locate and load the class or interface.
579 * It does not link the class, and does not run the class initializer.
580 * If the class is not found, this method returns {@code null}. </p>
581 *
582 * <p> If the class loader of the given module defines other modules and
583 * the given name is a class defined in a different module, this method
584 * returns {@code null} after the class is loaded. </p>
585 *
586 * <p> This method does not check whether the requested class is
587 * accessible to its caller. </p>
588 *
589 * @apiNote
590 * This method does not support loading of array types, unlike
591 * {@link #forName(String, boolean, ClassLoader)}. The class name must be
592 * a binary name. This method returns {@code null} on failure rather than
593 * throwing a {@link ClassNotFoundException}, as is done by
594 * the {@link #forName(String, boolean, ClassLoader)} method.
595 *
596 * @param module A module
597 * @param name The {@linkplain ClassLoader##binary-name binary name}
598 * of the class
599 * @return {@code Class} object of the given name defined in the given module;
600 * {@code null} if not found.
601 *
602 * @throws NullPointerException if the given module or name is {@code null}
603 *
604 * @throws LinkageError if the linkage fails
605 *
606 * @jls 12.2 Loading of Classes and Interfaces
607 * @jls 12.3 Linking of Classes and Interfaces
608 * @since 9
609 */
610 public static Class<?> forName(Module module, String name) {
611 Objects.requireNonNull(module);
612 Objects.requireNonNull(name);
613 if (!ModifiedUtf.isValidLengthInConstantPool(name)) {
614 return null;
615 }
616
617 ClassLoader cl = module.getClassLoader();
618 if (cl != null) {
619 return cl.loadClass(module, name);
620 } else {
621 return BootLoader.loadClass(module, name);
622 }
623 }
624
625 /**
626 * {@return {@code true} if this {@code Class} object represents an identity class,
627 * otherwise {@code false}}
628 *
629 * <ul>
630 * <li>
631 * If this {@code Class} object represents an array type this method returns {@code true}.
632 * <li>
633 * If this {@code Class} object represents an interface, a primitive type,
634 * or {@code void} this method returns {@code false}.
635 * <li>
636 * For all other {@code Class} objects, this method returns {@code true} if either
637 * preview features are disabled or {@linkplain Modifier#IDENTITY} is set in the
638 * {@linkplain #getModifiers() class modifiers}.
639 * </ul>
640 * @see AccessFlag#IDENTITY
641 * @since Valhalla
642 */
643 @PreviewFeature(feature = PreviewFeature.Feature.VALUE_OBJECTS, reflective=true)
644 public boolean isIdentity() {
645 if (isPrimitive()) {
646 return false;
647 } else if (PreviewFeatures.isEnabled()) {
648 return isArray() || Modifier.isIdentity(modifiers);
649 } else {
650 return !isInterface();
651 }
652 }
653
654 /**
655 * {@return {@code true} if this {@code Class} object represents a value class,
656 * otherwise {@code false}}
657 * <ul>
658 * <li>
659 * If this {@code Class} object represents an array type this method returns {@code false}.
660 * <li>
661 * If this {@code Class} object represents an interface, a primitive type,
662 * or {@code void} this method returns {@code true} only if preview features are enabled.
663 * <li>
664 * For all other {@code Class} objects, this method returns {@code true} only if
665 * preview features are enabled and {@linkplain Modifier#IDENTITY} is not set in the
666 * {@linkplain #getModifiers() class modifiers}.
667 * </ul>
668 * @see AccessFlag#IDENTITY
669 * @since Valhalla
670 */
671 @PreviewFeature(feature = PreviewFeature.Feature.VALUE_OBJECTS, reflective=true)
672 public boolean isValue() {
673 if (!PreviewFeatures.isEnabled()) {
674 return false;
675 }
676 return !isIdentity();
677 }
678
679 /**
680 * {@return the {@code Class} object associated with the
681 * {@linkplain #isPrimitive() primitive type} of the given name}
682 * If the argument is not the name of a primitive type, {@code
683 * null} is returned.
684 *
685 * @param primitiveName the name of the primitive type to find
686 *
687 * @throws NullPointerException if the argument is {@code null}
688 *
689 * @jls 4.2 Primitive Types and Values
690 * @jls 15.8.2 Class Literals
691 * @since 22
692 */
693 public static Class<?> forPrimitiveName(String primitiveName) {
694 return switch(primitiveName) {
695 // Integral types
696 case "int" -> int.class;
697 case "long" -> long.class;
698 case "short" -> short.class;
699 case "char" -> char.class;
700 case "byte" -> byte.class;
701
702 // Floating-point types
703 case "float" -> float.class;
704 case "double" -> double.class;
705
706 // Other types
707 case "boolean" -> boolean.class;
708 case "void" -> void.class;
709
710 default -> null;
711 };
712 }
713
714 /**
715 * Creates a new instance of the class represented by this {@code Class}
716 * object. The class is instantiated as if by a {@code new}
717 * expression with an empty argument list. The class is initialized if it
718 * has not already been initialized.
719 *
720 * @deprecated This method propagates any exception thrown by the
721 * nullary constructor, including a checked exception. Use of
722 * this method effectively bypasses the compile-time exception
723 * checking that would otherwise be performed by the compiler.
724 * The {@link
725 * java.lang.reflect.Constructor#newInstance(java.lang.Object...)
726 * Constructor.newInstance} method avoids this problem by wrapping
727 * any exception thrown by the constructor in a (checked) {@link
728 * java.lang.reflect.InvocationTargetException}.
729 *
730 * <p>The call
731 *
732 * {@snippet lang="java" :
733 * clazz.newInstance()
734 * }
735 *
736 * can be replaced by
737 *
738 * {@snippet lang="java" :
739 * clazz.getDeclaredConstructor().newInstance()
740 * }
741 *
742 * The latter sequence of calls is inferred to be able to throw
743 * the additional exception types {@link
744 * InvocationTargetException} and {@link
745 * NoSuchMethodException}. Both of these exception types are
746 * subclasses of {@link ReflectiveOperationException}.
747 *
748 * @return a newly allocated instance of the class represented by this
749 * object.
750 * @throws IllegalAccessException if the class or its nullary
751 * constructor is not accessible.
752 * @throws InstantiationException
753 * if this {@code Class} represents an abstract class,
754 * an interface, an array class, a primitive type, or void;
755 * or if the class has no nullary constructor;
756 * or if the instantiation fails for some other reason.
757 * @throws ExceptionInInitializerError if the initialization
758 * provoked by this method fails.
759 */
760 @CallerSensitive
761 @Deprecated(since="9")
762 public T newInstance()
763 throws InstantiationException, IllegalAccessException
764 {
765 // Constructor lookup
766 Constructor<T> tmpConstructor = cachedConstructor;
767 if (tmpConstructor == null) {
768 if (this == Class.class) {
769 throw new IllegalAccessException(
770 "Can not call newInstance() on the Class for java.lang.Class"
771 );
772 }
773 try {
774 Class<?>[] empty = {};
775 final Constructor<T> c = getReflectionFactory().copyConstructor(
776 getConstructor0(empty, Member.DECLARED));
777 // Disable accessibility checks on the constructor
778 // access check is done with the true caller
779 c.setAccessible(true);
780 cachedConstructor = tmpConstructor = c;
781 } catch (NoSuchMethodException e) {
782 throw (InstantiationException)
783 new InstantiationException(getName()).initCause(e);
784 }
785 }
786
787 try {
788 Class<?> caller = Reflection.getCallerClass();
789 return getReflectionFactory().newInstance(tmpConstructor, null, caller);
790 } catch (InvocationTargetException e) {
791 Unsafe.getUnsafe().throwException(e.getTargetException());
792 // Not reached
793 return null;
794 }
795 }
796
797 private transient volatile Constructor<T> cachedConstructor;
798
799 /**
800 * Determines if the specified {@code Object} is assignment-compatible
801 * with the object represented by this {@code Class}. This method is
802 * the dynamic equivalent of the Java language {@code instanceof}
803 * operator. The method returns {@code true} if the specified
804 * {@code Object} argument is non-null and can be cast to the
805 * reference type represented by this {@code Class} object without
806 * raising a {@code ClassCastException.} It returns {@code false}
807 * otherwise.
808 *
809 * <p> Specifically, if this {@code Class} object represents a
810 * declared class, this method returns {@code true} if the specified
811 * {@code Object} argument is an instance of the represented class (or
812 * of any of its subclasses); it returns {@code false} otherwise. If
813 * this {@code Class} object represents an array class, this method
814 * returns {@code true} if the specified {@code Object} argument
815 * can be converted to an object of the array class by an identity
816 * conversion or by a widening reference conversion; it returns
817 * {@code false} otherwise. If this {@code Class} object
818 * represents an interface, this method returns {@code true} if the
819 * class or any superclass of the specified {@code Object} argument
820 * implements this interface; it returns {@code false} otherwise. If
821 * this {@code Class} object represents a primitive type, this method
822 * returns {@code false}.
823 *
824 * @param obj the object to check
825 * @return true if {@code obj} is an instance of this class
826 *
827 * @since 1.1
828 */
829 @IntrinsicCandidate
830 public native boolean isInstance(Object obj);
831
832
833 /**
834 * Determines if the class or interface represented by this
835 * {@code Class} object is either the same as, or is a superclass or
836 * superinterface of, the class or interface represented by the specified
837 * {@code Class} parameter. It returns {@code true} if so;
838 * otherwise it returns {@code false}. If this {@code Class}
839 * object represents a primitive type, this method returns
840 * {@code true} if the specified {@code Class} parameter is
841 * exactly this {@code Class} object; otherwise it returns
842 * {@code false}.
843 *
844 * <p> Specifically, this method tests whether the type represented by the
845 * specified {@code Class} parameter can be converted to the type
846 * represented by this {@code Class} object via an identity conversion
847 * or via a widening reference conversion. See <cite>The Java Language
848 * Specification</cite>, sections {@jls 5.1.1} and {@jls 5.1.4},
849 * for details.
850 *
851 * @param cls the {@code Class} object to be checked
852 * @return the {@code boolean} value indicating whether objects of the
853 * type {@code cls} can be assigned to objects of this class
854 * @throws NullPointerException if the specified Class parameter is
855 * null.
856 * @since 1.1
857 */
858 @IntrinsicCandidate
859 public native boolean isAssignableFrom(Class<?> cls);
860
861
862 /**
863 * Determines if this {@code Class} object represents an
864 * interface type.
865 *
866 * @return {@code true} if this {@code Class} object represents an interface;
867 * {@code false} otherwise.
868 */
869 public boolean isInterface() {
870 return Modifier.isInterface(modifiers);
871 }
872
873
874 /**
875 * Determines if this {@code Class} object represents an array class.
876 *
877 * @return {@code true} if this {@code Class} object represents an array class;
878 * {@code false} otherwise.
879 * @since 1.1
880 */
881 public boolean isArray() {
882 return componentType != null;
883 }
884
885
886 /**
887 * Determines if this {@code Class} object represents a primitive
888 * type or void.
889 *
890 * <p> There are nine predefined {@code Class} objects to
891 * represent the eight primitive types and void. These are
892 * created by the Java Virtual Machine, and have the same
893 * {@linkplain #getName() names} as the primitive types that they
894 * represent, namely {@code boolean}, {@code byte}, {@code char},
895 * {@code short}, {@code int}, {@code long}, {@code float}, and
896 * {@code double}.
897 *
898 * <p>No other class objects are considered primitive.
899 *
900 * @apiNote
901 * A {@code Class} object represented by a primitive type can be
902 * accessed via the {@code TYPE} public static final variables
903 * defined in the primitive wrapper classes such as {@link
904 * java.lang.Integer#TYPE Integer.TYPE}. In the Java programming
905 * language, the objects may be referred to by a class literal
906 * expression such as {@code int.class}. The {@code Class} object
907 * for void can be expressed as {@code void.class} or {@link
908 * java.lang.Void#TYPE Void.TYPE}.
909 *
910 * @return true if and only if this class represents a primitive type
911 *
912 * @see java.lang.Boolean#TYPE
913 * @see java.lang.Character#TYPE
914 * @see java.lang.Byte#TYPE
915 * @see java.lang.Short#TYPE
916 * @see java.lang.Integer#TYPE
917 * @see java.lang.Long#TYPE
918 * @see java.lang.Float#TYPE
919 * @see java.lang.Double#TYPE
920 * @see java.lang.Void#TYPE
921 * @since 1.1
922 * @jls 15.8.2 Class Literals
923 */
924 public boolean isPrimitive() {
925 return primitive;
926 }
927
928 /**
929 * Returns true if this {@code Class} object represents an annotation
930 * interface. Note that if this method returns true, {@link #isInterface()}
931 * would also return true, as all annotation interfaces are also interfaces.
932 *
933 * @return {@code true} if this {@code Class} object represents an annotation
934 * interface; {@code false} otherwise
935 * @since 1.5
936 */
937 public boolean isAnnotation() {
938 return (getModifiers() & ANNOTATION) != 0;
939 }
940
941 /**
942 *{@return {@code true} if and only if this class has the synthetic modifier
943 * bit set}
944 *
945 * @jls 13.1 The Form of a Binary
946 * @jvms 4.1 The {@code ClassFile} Structure
947 * @see <a
948 * href="{@docRoot}/java.base/java/lang/reflect/package-summary.html#LanguageJvmModel">Java
949 * programming language and JVM modeling in core reflection</a>
950 * @since 1.5
951 */
952 public boolean isSynthetic() {
953 return (getModifiers() & SYNTHETIC) != 0;
954 }
955
956 /**
957 * Returns the name of the entity (class, interface, array class,
958 * primitive type, or void) represented by this {@code Class} object.
959 *
960 * <p> If this {@code Class} object represents a class or interface,
961 * not an array class, then:
962 * <ul>
963 * <li> If the class or interface is not {@linkplain #isHidden() hidden},
964 * then the {@linkplain ClassLoader##binary-name binary name}
965 * of the class or interface is returned.
966 * <li> If the class or interface is hidden, then the result is a string
967 * of the form: {@code N + '/' + <suffix>}
968 * where {@code N} is the {@linkplain ClassLoader##binary-name binary name}
969 * indicated by the {@code class} file passed to
970 * {@link java.lang.invoke.MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
971 * Lookup::defineHiddenClass}, and {@code <suffix>} is an unqualified name.
972 * </ul>
973 *
974 * <p> If this {@code Class} object represents an array class, then
975 * the result is a string consisting of one or more '{@code [}' characters
976 * representing the depth of the array nesting, followed by the element
977 * type as encoded using the following table:
978 *
979 * <blockquote><table class="striped" id="nameFormat">
980 * <caption style="display:none">Element types and encodings</caption>
981 * <thead>
982 * <tr><th scope="col"> Element Type <th scope="col"> Encoding
983 * </thead>
984 * <tbody style="text-align:left">
985 * <tr><th scope="row"> {@code boolean} <td style="text-align:center"> {@code Z}
986 * <tr><th scope="row"> {@code byte} <td style="text-align:center"> {@code B}
987 * <tr><th scope="row"> {@code char} <td style="text-align:center"> {@code C}
988 * <tr><th scope="row"> class or interface with {@linkplain ClassLoader##binary-name binary name} <i>N</i>
989 * <td style="text-align:center"> {@code L}<em>N</em>{@code ;}
990 * <tr><th scope="row"> {@code double} <td style="text-align:center"> {@code D}
991 * <tr><th scope="row"> {@code float} <td style="text-align:center"> {@code F}
992 * <tr><th scope="row"> {@code int} <td style="text-align:center"> {@code I}
993 * <tr><th scope="row"> {@code long} <td style="text-align:center"> {@code J}
994 * <tr><th scope="row"> {@code short} <td style="text-align:center"> {@code S}
995 * </tbody>
996 * </table></blockquote>
997 *
998 * <p> If this {@code Class} object represents a primitive type or {@code void},
999 * then the result is a string with the same spelling as the Java language
1000 * keyword which corresponds to the primitive type or {@code void}.
1001 *
1002 * <p> Examples:
1003 * <blockquote><pre>
1004 * String.class.getName()
1005 * returns "java.lang.String"
1006 * Character.UnicodeBlock.class.getName()
1007 * returns "java.lang.Character$UnicodeBlock"
1008 * byte.class.getName()
1009 * returns "byte"
1010 * (new Object[3]).getClass().getName()
1011 * returns "[Ljava.lang.Object;"
1012 * (new int[3][4][5][6][7][8][9]).getClass().getName()
1013 * returns "[[[[[[[I"
1014 * </pre></blockquote>
1015 *
1016 * @apiNote
1017 * Distinct class objects can have the same name but different class loaders.
1018 *
1019 * @return the name of the class, interface, or other entity
1020 * represented by this {@code Class} object.
1021 * @jls 13.1 The Form of a Binary
1022 */
1023 public String getName() {
1024 String name = this.name;
1025 return name != null ? name : initClassName();
1026 }
1027
1028 // Cache the name to reduce the number of calls into the VM.
1029 // This field would be set by VM itself during initClassName call.
1030 private transient String name;
1031 private native String initClassName();
1032
1033 /**
1034 * Returns the class loader for the class. Some implementations may use
1035 * null to represent the bootstrap class loader. This method will return
1036 * null in such implementations if this class was loaded by the bootstrap
1037 * class loader.
1038 *
1039 * <p>If this {@code Class} object
1040 * represents a primitive type or void, null is returned.
1041 *
1042 * @return the class loader that loaded the class or interface
1043 * represented by this {@code Class} object.
1044 * @see java.lang.ClassLoader
1045 */
1046 public ClassLoader getClassLoader() {
1047 return classLoader;
1048 }
1049
1050 // Package-private to allow ClassLoader access
1051 ClassLoader getClassLoader0() { return classLoader; }
1052
1053 /**
1054 * Returns the module that this class or interface is a member of.
1055 *
1056 * If this class represents an array type then this method returns the
1057 * {@code Module} for the element type. If this class represents a
1058 * primitive type or void, then the {@code Module} object for the
1059 * {@code java.base} module is returned.
1060 *
1061 * If this class is in an unnamed module then the {@linkplain
1062 * ClassLoader#getUnnamedModule() unnamed} {@code Module} of the class
1063 * loader for this class is returned.
1064 *
1065 * @return the module that this class or interface is a member of
1066 *
1067 * @since 9
1068 */
1069 public Module getModule() {
1070 return module;
1071 }
1072
1073 // set by VM
1074 @Stable
1075 private transient Module module;
1076
1077 // Initialized in JVM not by private constructor
1078 // This field is filtered from reflection access, i.e. getDeclaredField
1079 // will throw NoSuchFieldException
1080 private final ClassLoader classLoader;
1081
1082 private transient Object classData; // Set by VM
1083 private transient Object[] signers; // Read by VM, mutable
1084 private final transient char modifiers; // Set by the VM
1085 private final transient char classFileAccessFlags; // Set by the VM
1086 private final transient boolean primitive; // Set by the VM if the Class is a primitive type.
1087
1088 // package-private
1089 Object getClassData() {
1090 return classData;
1091 }
1092
1093 /**
1094 * Returns an array of {@code TypeVariable} objects that represent the
1095 * type variables declared by the generic declaration represented by this
1096 * {@code GenericDeclaration} object, in declaration order. Returns an
1097 * array of length 0 if the underlying generic declaration declares no type
1098 * variables.
1099 *
1100 * @return an array of {@code TypeVariable} objects that represent
1101 * the type variables declared by this generic declaration
1102 * @throws java.lang.reflect.GenericSignatureFormatError if the generic
1103 * signature of this generic declaration does not conform to
1104 * the format specified in section {@jvms 4.7.9} of
1105 * <cite>The Java Virtual Machine Specification</cite>
1106 * @since 1.5
1107 */
1108 @SuppressWarnings("unchecked")
1109 public TypeVariable<Class<T>>[] getTypeParameters() {
1110 ClassRepository info = getGenericInfo();
1111 if (info != null)
1112 return (TypeVariable<Class<T>>[])info.getTypeParameters();
1113 else
1114 return (TypeVariable<Class<T>>[])new TypeVariable<?>[0];
1115 }
1116
1117
1118 /**
1119 * Returns the {@code Class} representing the direct superclass of the
1120 * entity (class, interface, primitive type or void) represented by
1121 * this {@code Class}. If this {@code Class} represents either the
1122 * {@code Object} class, an interface, a primitive type, or void, then
1123 * null is returned. If this {@code Class} object represents an array class
1124 * then the {@code Class} object representing the {@code Object} class is
1125 * returned.
1126 *
1127 * @return the direct superclass of the class represented by this {@code Class} object
1128 */
1129 @IntrinsicCandidate
1130 public native Class<? super T> getSuperclass();
1131
1132
1133 /**
1134 * Returns the {@code Type} representing the direct superclass of
1135 * the entity (class, interface, primitive type or void) represented by
1136 * this {@code Class} object.
1137 *
1138 * <p>If the superclass is a parameterized type, the {@code Type}
1139 * object returned must accurately reflect the actual type
1140 * arguments used in the source code. The parameterized type
1141 * representing the superclass is created if it had not been
1142 * created before. See the declaration of {@link
1143 * java.lang.reflect.ParameterizedType ParameterizedType} for the
1144 * semantics of the creation process for parameterized types. If
1145 * this {@code Class} object represents either the {@code Object}
1146 * class, an interface, a primitive type, or void, then null is
1147 * returned. If this {@code Class} object represents an array class
1148 * then the {@code Class} object representing the {@code Object} class is
1149 * returned.
1150 *
1151 * @throws java.lang.reflect.GenericSignatureFormatError if the generic
1152 * class signature does not conform to the format specified in
1153 * section {@jvms 4.7.9} of <cite>The Java Virtual
1154 * Machine Specification</cite>
1155 * @throws TypeNotPresentException if the generic superclass
1156 * refers to a non-existent type declaration
1157 * @throws java.lang.reflect.MalformedParameterizedTypeException if the
1158 * generic superclass refers to a parameterized type that cannot be
1159 * instantiated for any reason
1160 * @return the direct superclass of the class represented by this {@code Class} object
1161 * @since 1.5
1162 */
1163 public Type getGenericSuperclass() {
1164 ClassRepository info = getGenericInfo();
1165 if (info == null) {
1166 return getSuperclass();
1167 }
1168
1169 // Historical irregularity:
1170 // Generic signature marks interfaces with superclass = Object
1171 // but this API returns null for interfaces
1172 if (isInterface()) {
1173 return null;
1174 }
1175
1176 return info.getSuperclass();
1177 }
1178
1179 /**
1180 * Gets the package of this class.
1181 *
1182 * <p>If this class represents an array type, a primitive type or void,
1183 * this method returns {@code null}.
1184 *
1185 * @return the package of this class.
1186 */
1187 public Package getPackage() {
1188 if (isPrimitive() || isArray()) {
1189 return null;
1190 }
1191 ClassLoader cl = classLoader;
1192 return cl != null ? cl.definePackage(this)
1193 : BootLoader.definePackage(this);
1194 }
1195
1196 /**
1197 * Returns the fully qualified package name.
1198 *
1199 * <p> If this class is a top level class, then this method returns the fully
1200 * qualified name of the package that the class is a member of, or the
1201 * empty string if the class is in an unnamed package.
1202 *
1203 * <p> If this class is a member class, then this method is equivalent to
1204 * invoking {@code getPackageName()} on the {@linkplain #getEnclosingClass
1205 * enclosing class}.
1206 *
1207 * <p> If this class is a {@linkplain #isLocalClass local class} or an {@linkplain
1208 * #isAnonymousClass() anonymous class}, then this method is equivalent to
1209 * invoking {@code getPackageName()} on the {@linkplain #getDeclaringClass
1210 * declaring class} of the {@linkplain #getEnclosingMethod enclosing method} or
1211 * {@linkplain #getEnclosingConstructor enclosing constructor}.
1212 *
1213 * <p> If this class represents an array type then this method returns the
1214 * package name of the element type. If this class represents a primitive
1215 * type or void then the package name "{@code java.lang}" is returned.
1216 *
1217 * @return the fully qualified package name
1218 *
1219 * @since 9
1220 * @jls 6.7 Fully Qualified Names and Canonical Names
1221 */
1222 public String getPackageName() {
1223 String pn = this.packageName;
1224 if (pn == null) {
1225 Class<?> c = isArray() ? elementType() : this;
1226 if (c.isPrimitive()) {
1227 pn = "java.lang";
1228 } else {
1229 String cn = c.getName();
1230 int dot = cn.lastIndexOf('.');
1231 pn = (dot != -1) ? cn.substring(0, dot).intern() : "";
1232 }
1233 this.packageName = pn;
1234 }
1235 return pn;
1236 }
1237
1238 // cached package name
1239 private transient String packageName;
1240
1241 /**
1242 * Returns the interfaces directly implemented by the class or interface
1243 * represented by this {@code Class} object.
1244 *
1245 * <p>If this {@code Class} object represents a class, the return value is an array
1246 * containing objects representing all interfaces directly implemented by
1247 * the class. The order of the interface objects in the array corresponds
1248 * to the order of the interface names in the {@code implements} clause of
1249 * the declaration of the class represented by this {@code Class} object. For example,
1250 * given the declaration:
1251 * <blockquote>
1252 * {@code class Shimmer implements FloorWax, DessertTopping { ... }}
1253 * </blockquote>
1254 * suppose the value of {@code s} is an instance of
1255 * {@code Shimmer}; the value of the expression:
1256 * <blockquote>
1257 * {@code s.getClass().getInterfaces()[0]}
1258 * </blockquote>
1259 * is the {@code Class} object that represents interface
1260 * {@code FloorWax}; and the value of:
1261 * <blockquote>
1262 * {@code s.getClass().getInterfaces()[1]}
1263 * </blockquote>
1264 * is the {@code Class} object that represents interface
1265 * {@code DessertTopping}.
1266 *
1267 * <p>If this {@code Class} object represents an interface, the array contains objects
1268 * representing all interfaces directly extended by the interface. The
1269 * order of the interface objects in the array corresponds to the order of
1270 * the interface names in the {@code extends} clause of the declaration of
1271 * the interface represented by this {@code Class} object.
1272 *
1273 * <p>If this {@code Class} object represents a class or interface that implements no
1274 * interfaces, the method returns an array of length 0.
1275 *
1276 * <p>If this {@code Class} object represents a primitive type or void, the method
1277 * returns an array of length 0.
1278 *
1279 * <p>If this {@code Class} object represents an array type, the
1280 * interfaces {@code Cloneable} and {@code java.io.Serializable} are
1281 * returned in that order.
1282 *
1283 * @return an array of interfaces directly implemented by this class
1284 */
1285 public Class<?>[] getInterfaces() {
1286 // defensively copy before handing over to user code
1287 return getInterfaces(true);
1288 }
1289
1290 private Class<?>[] getInterfaces(boolean cloneArray) {
1291 ReflectionData<T> rd = reflectionData();
1292 Class<?>[] interfaces = rd.interfaces;
1293 if (interfaces == null) {
1294 interfaces = getInterfaces0();
1295 rd.interfaces = interfaces;
1296 }
1297 // defensively copy if requested
1298 return cloneArray ? interfaces.clone() : interfaces;
1299 }
1300
1301 private native Class<?>[] getInterfaces0();
1302
1303 /**
1304 * Returns the {@code Type}s representing the interfaces
1305 * directly implemented by the class or interface represented by
1306 * this {@code Class} object.
1307 *
1308 * <p>If a superinterface is a parameterized type, the
1309 * {@code Type} object returned for it must accurately reflect
1310 * the actual type arguments used in the source code. The
1311 * parameterized type representing each superinterface is created
1312 * if it had not been created before. See the declaration of
1313 * {@link java.lang.reflect.ParameterizedType ParameterizedType}
1314 * for the semantics of the creation process for parameterized
1315 * types.
1316 *
1317 * <p>If this {@code Class} object represents a class, the return value is an array
1318 * containing objects representing all interfaces directly implemented by
1319 * the class. The order of the interface objects in the array corresponds
1320 * to the order of the interface names in the {@code implements} clause of
1321 * the declaration of the class represented by this {@code Class} object.
1322 *
1323 * <p>If this {@code Class} object represents an interface, the array contains objects
1324 * representing all interfaces directly extended by the interface. The
1325 * order of the interface objects in the array corresponds to the order of
1326 * the interface names in the {@code extends} clause of the declaration of
1327 * the interface represented by this {@code Class} object.
1328 *
1329 * <p>If this {@code Class} object represents a class or interface that implements no
1330 * interfaces, the method returns an array of length 0.
1331 *
1332 * <p>If this {@code Class} object represents a primitive type or void, the method
1333 * returns an array of length 0.
1334 *
1335 * <p>If this {@code Class} object represents an array type, the
1336 * interfaces {@code Cloneable} and {@code java.io.Serializable} are
1337 * returned in that order.
1338 *
1339 * @throws java.lang.reflect.GenericSignatureFormatError
1340 * if the generic class signature does not conform to the
1341 * format specified in section {@jvms 4.7.9} of <cite>The
1342 * Java Virtual Machine Specification</cite>
1343 * @throws TypeNotPresentException if any of the generic
1344 * superinterfaces refers to a non-existent type declaration
1345 * @throws java.lang.reflect.MalformedParameterizedTypeException
1346 * if any of the generic superinterfaces refer to a parameterized
1347 * type that cannot be instantiated for any reason
1348 * @return an array of interfaces directly implemented by this class
1349 * @since 1.5
1350 */
1351 public Type[] getGenericInterfaces() {
1352 ClassRepository info = getGenericInfo();
1353 return (info == null) ? getInterfaces() : info.getSuperInterfaces();
1354 }
1355
1356
1357 /**
1358 * Returns the {@code Class} representing the component type of an
1359 * array. If this class does not represent an array class this method
1360 * returns null.
1361 *
1362 * @return the {@code Class} representing the component type of this
1363 * class if this class is an array
1364 * @see java.lang.reflect.Array
1365 * @since 1.1
1366 */
1367 public Class<?> getComponentType() {
1368 return componentType;
1369 }
1370
1371 // The componentType field's null value is the sole indication that the class
1372 // is an array - see isArray().
1373 private transient final Class<?> componentType;
1374
1375 /*
1376 * Returns the {@code Class} representing the element type of an array class.
1377 * If this class does not represent an array class, then this method returns
1378 * {@code null}.
1379 */
1380 private Class<?> elementType() {
1381 if (!isArray()) return null;
1382
1383 Class<?> c = this;
1384 while (c.isArray()) {
1385 c = c.getComponentType();
1386 }
1387 return c;
1388 }
1389
1390 /**
1391 * Returns the Java language modifiers for this class or interface, encoded
1392 * in an integer. The modifiers consist of the Java Virtual Machine's
1393 * constants for {@code public}, {@code protected},
1394 * {@code private}, {@code final}, {@code static},
1395 * {@code abstract} and {@code interface}; they should be decoded
1396 * using the methods of class {@code Modifier}.
1397 *
1398 * <p> If the underlying class is an array class:
1399 * <ul>
1400 * <li> its {@code public}, {@code private} and {@code protected}
1401 * modifiers are the same as those of its component type
1402 * <li> its {@code abstract} and {@code final} modifiers are always
1403 * {@code true}
1404 * <li> its interface modifier is always {@code false}, even when
1405 * the component type is an interface
1406 * <li> its {@code identity} modifier is always true
1407 * </ul>
1408 * If this {@code Class} object represents a primitive type or
1409 * void, its {@code public}, {@code abstract}, and {@code final}
1410 * modifiers are always {@code true}.
1411 * For {@code Class} objects representing void, primitive types, and
1412 * arrays, the values of other modifiers are {@code false} other
1413 * than as specified above.
1414 *
1415 * <p> The modifier encodings are defined in section {@jvms 4.1}
1416 * of <cite>The Java Virtual Machine Specification</cite>.
1417 *
1418 * @return the {@code int} representing the modifiers for this class
1419 * @see java.lang.reflect.Modifier
1420 * @see #accessFlags()
1421 * @see <a
1422 * href="{@docRoot}/java.base/java/lang/reflect/package-summary.html#LanguageJvmModel">Java
1423 * programming language and JVM modeling in core reflection</a>
1424 * @since 1.1
1425 * @jls 8.1.1 Class Modifiers
1426 * @jls 9.1.1 Interface Modifiers
1427 * @jvms 4.1 The {@code ClassFile} Structure
1428 */
1429 public int getModifiers() { return modifiers; }
1430
1431 /**
1432 * {@return an unmodifiable set of the {@linkplain AccessFlag access
1433 * flags} for this class, possibly empty}
1434 * The {@code AccessFlags} may depend on the class file format version of the class.
1435 *
1436 * <p> If the underlying class is an array class:
1437 * <ul>
1438 * <li> its {@code PUBLIC}, {@code PRIVATE} and {@code PROTECTED}
1439 * access flags are the same as those of its component type
1440 * <li> its {@code ABSTRACT} and {@code FINAL} flags are present
1441 * <li> its {@code INTERFACE} flag is absent, even when the
1442 * component type is an interface
1443 * <li> its {@code identity} modifier is always true
1444 * </ul>
1445 * If this {@code Class} object represents a primitive type or
1446 * void, the flags are {@code PUBLIC}, {@code ABSTRACT}, and
1447 * {@code FINAL}.
1448 * For {@code Class} objects representing void, primitive types, and
1449 * arrays, access flags are absent other than as specified above.
1450 *
1451 * @see #getModifiers()
1452 * @jvms 4.1 The ClassFile Structure
1453 * @jvms 4.7.6 The InnerClasses Attribute
1454 * @since 20
1455 */
1456 public Set<AccessFlag> accessFlags() {
1457 // Location.CLASS allows SUPER and AccessFlag.MODULE which
1458 // INNER_CLASS forbids. INNER_CLASS allows PRIVATE, PROTECTED,
1459 // and STATIC, which are not allowed on Location.CLASS.
1460 // Use getClassFileAccessFlags to expose SUPER status.
1461 // Arrays need to use PRIVATE/PROTECTED from its component modifiers.
1462 var location = (isMemberClass() || isLocalClass() ||
1463 isAnonymousClass() || isArray()) ?
1464 AccessFlag.Location.INNER_CLASS :
1465 AccessFlag.Location.CLASS;
1466 int accessFlags = location == AccessFlag.Location.CLASS ? getClassFileAccessFlags() : getModifiers();
1467 var reflectionFactory = getReflectionFactory();
1468 var ans = reflectionFactory.parseAccessFlags(accessFlags, location, this);
1469 if (PreviewFeatures.isEnabled() && reflectionFactory.classFileFormatVersion(this) != ClassFileFormatVersion.CURRENT_PREVIEW_FEATURES
1470 && isIdentity()) {
1471 var set = new HashSet<>(ans);
1472 set.add(AccessFlag.IDENTITY);
1473 return Set.copyOf(set);
1474 }
1475 return ans;
1476 }
1477
1478 /**
1479 * Gets the signers of this class.
1480 *
1481 * @return the signers of this class, or null if there are no signers. In
1482 * particular, this method returns null if this {@code Class} object represents
1483 * a primitive type or void.
1484 * @since 1.1
1485 */
1486
1487 public Object[] getSigners() {
1488 var signers = this.signers;
1489 return signers == null ? null : signers.clone();
1490 }
1491
1492 /**
1493 * Set the signers of this class.
1494 */
1495 void setSigners(Object[] signers) {
1496 if (!isPrimitive() && !isArray()) {
1497 this.signers = signers;
1498 }
1499 }
1500
1501 /**
1502 * If this {@code Class} object represents a local or anonymous
1503 * class within a method, returns a {@link
1504 * java.lang.reflect.Method Method} object representing the
1505 * immediately enclosing method of the underlying class. Returns
1506 * {@code null} otherwise.
1507 *
1508 * In particular, this method returns {@code null} if the underlying
1509 * class is a local or anonymous class immediately enclosed by a class or
1510 * interface declaration, instance initializer or static initializer.
1511 *
1512 * @return the immediately enclosing method of the underlying class, if
1513 * that class is a local or anonymous class; otherwise {@code null}.
1514 *
1515 * @since 1.5
1516 */
1517 public Method getEnclosingMethod() {
1518 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1519
1520 if (enclosingInfo == null)
1521 return null;
1522 else {
1523 if (!enclosingInfo.isMethod())
1524 return null;
1525
1526 // Descriptor already validated by VM
1527 List<Class<?>> types = BytecodeDescriptor.parseMethod(enclosingInfo.getDescriptor(), getClassLoader());
1528 Class<?> returnType = types.removeLast();
1529 Class<?>[] parameterClasses = types.toArray(EMPTY_CLASS_ARRAY);
1530
1531 final Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass();
1532 Method[] candidates = enclosingCandidate.privateGetDeclaredMethods(false);
1533
1534 /*
1535 * Loop over all declared methods; match method name,
1536 * number of and type of parameters, *and* return
1537 * type. Matching return type is also necessary
1538 * because of covariant returns, etc.
1539 */
1540 ReflectionFactory fact = getReflectionFactory();
1541 for (Method m : candidates) {
1542 if (m.getName().equals(enclosingInfo.getName()) &&
1543 arrayContentsEq(parameterClasses,
1544 fact.getExecutableSharedParameterTypes(m))) {
1545 // finally, check return type
1546 if (m.getReturnType().equals(returnType)) {
1547 return fact.copyMethod(m);
1548 }
1549 }
1550 }
1551
1552 throw new InternalError("Enclosing method not found");
1553 }
1554 }
1555
1556 private native Object[] getEnclosingMethod0();
1557
1558 private EnclosingMethodInfo getEnclosingMethodInfo() {
1559 Object[] enclosingInfo = getEnclosingMethod0();
1560 if (enclosingInfo == null)
1561 return null;
1562 else {
1563 return new EnclosingMethodInfo(enclosingInfo);
1564 }
1565 }
1566
1567 private static final class EnclosingMethodInfo {
1568 private final Class<?> enclosingClass;
1569 private final String name;
1570 private final String descriptor;
1571
1572 static void validate(Object[] enclosingInfo) {
1573 if (enclosingInfo.length != 3)
1574 throw new InternalError("Malformed enclosing method information");
1575 try {
1576 // The array is expected to have three elements:
1577
1578 // the immediately enclosing class
1579 Class<?> enclosingClass = (Class<?>)enclosingInfo[0];
1580 assert(enclosingClass != null);
1581
1582 // the immediately enclosing method or constructor's
1583 // name (can be null).
1584 String name = (String)enclosingInfo[1];
1585
1586 // the immediately enclosing method or constructor's
1587 // descriptor (null iff name is).
1588 String descriptor = (String)enclosingInfo[2];
1589 assert((name != null && descriptor != null) || name == descriptor);
1590 } catch (ClassCastException cce) {
1591 throw new InternalError("Invalid type in enclosing method information", cce);
1592 }
1593 }
1594
1595 EnclosingMethodInfo(Object[] enclosingInfo) {
1596 validate(enclosingInfo);
1597 this.enclosingClass = (Class<?>)enclosingInfo[0];
1598 this.name = (String)enclosingInfo[1];
1599 this.descriptor = (String)enclosingInfo[2];
1600 }
1601
1602 boolean isPartial() {
1603 return enclosingClass == null || name == null || descriptor == null;
1604 }
1605
1606 boolean isConstructor() { return !isPartial() && ConstantDescs.INIT_NAME.equals(name); }
1607
1608 boolean isMethod() { return !isPartial() && !isConstructor() && !ConstantDescs.CLASS_INIT_NAME.equals(name); }
1609
1610 Class<?> getEnclosingClass() { return enclosingClass; }
1611
1612 String getName() { return name; }
1613
1614 String getDescriptor() { return descriptor; }
1615
1616 }
1617
1618 private static Class<?> toClass(Type o) {
1619 if (o instanceof GenericArrayType gat)
1620 return toClass(gat.getGenericComponentType()).arrayType();
1621 return (Class<?>)o;
1622 }
1623
1624 /**
1625 * If this {@code Class} object represents a local or anonymous
1626 * class within a constructor, returns a {@link
1627 * java.lang.reflect.Constructor Constructor} object representing
1628 * the immediately enclosing constructor of the underlying
1629 * class. Returns {@code null} otherwise. In particular, this
1630 * method returns {@code null} if the underlying class is a local
1631 * or anonymous class immediately enclosed by a class or
1632 * interface declaration, instance initializer or static initializer.
1633 *
1634 * @return the immediately enclosing constructor of the underlying class, if
1635 * that class is a local or anonymous class; otherwise {@code null}.
1636 *
1637 * @since 1.5
1638 */
1639 public Constructor<?> getEnclosingConstructor() {
1640 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1641
1642 if (enclosingInfo == null)
1643 return null;
1644 else {
1645 if (!enclosingInfo.isConstructor())
1646 return null;
1647
1648 // Descriptor already validated by VM
1649 List<Class<?>> types = BytecodeDescriptor.parseMethod(enclosingInfo.getDescriptor(), getClassLoader());
1650 types.removeLast();
1651 Class<?>[] parameterClasses = types.toArray(EMPTY_CLASS_ARRAY);
1652
1653 final Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass();
1654 Constructor<?>[] candidates = enclosingCandidate
1655 .privateGetDeclaredConstructors(false);
1656 /*
1657 * Loop over all declared constructors; match number
1658 * of and type of parameters.
1659 */
1660 ReflectionFactory fact = getReflectionFactory();
1661 for (Constructor<?> c : candidates) {
1662 if (arrayContentsEq(parameterClasses,
1663 fact.getExecutableSharedParameterTypes(c))) {
1664 return fact.copyConstructor(c);
1665 }
1666 }
1667
1668 throw new InternalError("Enclosing constructor not found");
1669 }
1670 }
1671
1672
1673 /**
1674 * If the class or interface represented by this {@code Class} object
1675 * is a member of another class, returns the {@code Class} object
1676 * representing the class in which it was declared. This method returns
1677 * null if this class or interface is not a member of any other class. If
1678 * this {@code Class} object represents an array class, a primitive
1679 * type, or void, then this method returns null.
1680 *
1681 * @return the declaring class for this class
1682 * @since 1.1
1683 */
1684 public Class<?> getDeclaringClass() {
1685 return getDeclaringClass0();
1686 }
1687
1688 private native Class<?> getDeclaringClass0();
1689
1690
1691 /**
1692 * Returns the immediately enclosing class of the underlying
1693 * class. If the underlying class is a top level class this
1694 * method returns {@code null}.
1695 * @return the immediately enclosing class of the underlying class
1696 * @since 1.5
1697 */
1698 public Class<?> getEnclosingClass() {
1699 // There are five kinds of classes (or interfaces):
1700 // a) Top level classes
1701 // b) Nested classes (static member classes)
1702 // c) Inner classes (non-static member classes)
1703 // d) Local classes (named classes declared within a method)
1704 // e) Anonymous classes
1705
1706
1707 // JVM Spec 4.7.7: A class must have an EnclosingMethod
1708 // attribute if and only if it is a local class or an
1709 // anonymous class.
1710 EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
1711 Class<?> enclosingCandidate;
1712
1713 if (enclosingInfo == null) {
1714 // This is a top level or a nested class or an inner class (a, b, or c)
1715 enclosingCandidate = getDeclaringClass0();
1716 } else {
1717 Class<?> enclosingClass = enclosingInfo.getEnclosingClass();
1718 // This is a local class or an anonymous class (d or e)
1719 if (enclosingClass == this || enclosingClass == null)
1720 throw new InternalError("Malformed enclosing method information");
1721 else
1722 enclosingCandidate = enclosingClass;
1723 }
1724 return enclosingCandidate;
1725 }
1726
1727 /**
1728 * Returns the simple name of the underlying class as given in the
1729 * source code. An empty string is returned if the underlying class is
1730 * {@linkplain #isAnonymousClass() anonymous}.
1731 * A {@linkplain #isSynthetic() synthetic class}, one not present
1732 * in source code, can have a non-empty name including special
1733 * characters, such as "{@code $}".
1734 *
1735 * <p>The simple name of an {@linkplain #isArray() array class} is the simple name of the
1736 * component type with "[]" appended. In particular the simple
1737 * name of an array class whose component type is anonymous is "[]".
1738 *
1739 * @return the simple name of the underlying class
1740 * @since 1.5
1741 */
1742 public String getSimpleName() {
1743 ReflectionData<T> rd = reflectionData();
1744 String simpleName = rd.simpleName;
1745 if (simpleName == null) {
1746 rd.simpleName = simpleName = getSimpleName0();
1747 }
1748 return simpleName;
1749 }
1750
1751 private String getSimpleName0() {
1752 if (isArray()) {
1753 return getComponentType().getSimpleName().concat("[]");
1754 }
1755 String simpleName = getSimpleBinaryName();
1756 if (simpleName == null) { // top level class
1757 simpleName = getName();
1758 simpleName = simpleName.substring(simpleName.lastIndexOf('.') + 1); // strip the package name
1759 }
1760 return simpleName;
1761 }
1762
1763 /**
1764 * Return an informative string for the name of this class or interface.
1765 *
1766 * @return an informative string for the name of this class or interface
1767 * @since 1.8
1768 */
1769 public String getTypeName() {
1770 if (isArray()) {
1771 try {
1772 Class<?> cl = this;
1773 int dimensions = 0;
1774 do {
1775 dimensions++;
1776 cl = cl.getComponentType();
1777 } while (cl.isArray());
1778 return cl.getName().concat("[]".repeat(dimensions));
1779 } catch (Throwable e) { /*FALLTHRU*/ }
1780 }
1781 return getName();
1782 }
1783
1784 /**
1785 * Returns the canonical name of the underlying class as
1786 * defined by <cite>The Java Language Specification</cite>.
1787 * Returns {@code null} if the underlying class does not have a canonical
1788 * name. Classes without canonical names include:
1789 * <ul>
1790 * <li>a {@linkplain #isLocalClass() local class}
1791 * <li>a {@linkplain #isAnonymousClass() anonymous class}
1792 * <li>a {@linkplain #isHidden() hidden class}
1793 * <li>an array whose component type does not have a canonical name</li>
1794 * </ul>
1795 *
1796 * The canonical name for a primitive class is the keyword for the
1797 * corresponding primitive type ({@code byte}, {@code short},
1798 * {@code char}, {@code int}, and so on).
1799 *
1800 * <p>An array type has a canonical name if and only if its
1801 * component type has a canonical name. When an array type has a
1802 * canonical name, it is equal to the canonical name of the
1803 * component type followed by "{@code []}".
1804 *
1805 * @return the canonical name of the underlying class if it exists, and
1806 * {@code null} otherwise.
1807 * @jls 6.7 Fully Qualified Names and Canonical Names
1808 * @since 1.5
1809 */
1810 public String getCanonicalName() {
1811 ReflectionData<T> rd = reflectionData();
1812 String canonicalName = rd.canonicalName;
1813 if (canonicalName == null) {
1814 rd.canonicalName = canonicalName = getCanonicalName0();
1815 }
1816 return canonicalName == ReflectionData.NULL_SENTINEL? null : canonicalName;
1817 }
1818
1819 private String getCanonicalName0() {
1820 if (isArray()) {
1821 String canonicalName = getComponentType().getCanonicalName();
1822 if (canonicalName != null)
1823 return canonicalName.concat("[]");
1824 else
1825 return ReflectionData.NULL_SENTINEL;
1826 }
1827 if (isHidden() || isLocalOrAnonymousClass())
1828 return ReflectionData.NULL_SENTINEL;
1829 Class<?> enclosingClass = getEnclosingClass();
1830 if (enclosingClass == null) { // top level class
1831 return getName();
1832 } else {
1833 String enclosingName = enclosingClass.getCanonicalName();
1834 if (enclosingName == null)
1835 return ReflectionData.NULL_SENTINEL;
1836 String simpleName = getSimpleName();
1837 return new StringBuilder(enclosingName.length() + simpleName.length() + 1)
1838 .append(enclosingName)
1839 .append('.')
1840 .append(simpleName)
1841 .toString();
1842 }
1843 }
1844
1845 /**
1846 * Returns {@code true} if and only if the underlying class
1847 * is an anonymous class.
1848 *
1849 * @apiNote
1850 * An anonymous class is not a {@linkplain #isHidden() hidden class}.
1851 *
1852 * @return {@code true} if and only if this class is an anonymous class.
1853 * @since 1.5
1854 * @jls 15.9.5 Anonymous Class Declarations
1855 */
1856 public boolean isAnonymousClass() {
1857 return !isArray() && isLocalOrAnonymousClass() &&
1858 getSimpleBinaryName0() == null;
1859 }
1860
1861 /**
1862 * Returns {@code true} if and only if the underlying class
1863 * is a local class.
1864 *
1865 * @return {@code true} if and only if this class is a local class.
1866 * @since 1.5
1867 * @jls 14.3 Local Class and Interface Declarations
1868 */
1869 public boolean isLocalClass() {
1870 return isLocalOrAnonymousClass() &&
1871 (isArray() || getSimpleBinaryName0() != null);
1872 }
1873
1874 /**
1875 * Returns {@code true} if and only if the underlying class
1876 * is a member class.
1877 *
1878 * @return {@code true} if and only if this class is a member class.
1879 * @since 1.5
1880 * @jls 8.5 Member Class and Interface Declarations
1881 */
1882 public boolean isMemberClass() {
1883 return !isLocalOrAnonymousClass() && getDeclaringClass0() != null;
1884 }
1885
1886 /**
1887 * Returns the "simple binary name" of the underlying class, i.e.,
1888 * the binary name without the leading enclosing class name.
1889 * Returns {@code null} if the underlying class is a top level
1890 * class.
1891 */
1892 private String getSimpleBinaryName() {
1893 if (isTopLevelClass())
1894 return null;
1895 String name = getSimpleBinaryName0();
1896 if (name == null) // anonymous class
1897 return "";
1898 return name;
1899 }
1900
1901 private native String getSimpleBinaryName0();
1902
1903 /**
1904 * Returns {@code true} if this is a top level class. Returns {@code false}
1905 * otherwise.
1906 */
1907 private boolean isTopLevelClass() {
1908 return !isLocalOrAnonymousClass() && getDeclaringClass0() == null;
1909 }
1910
1911 /**
1912 * Returns {@code true} if this is a local class or an anonymous
1913 * class. Returns {@code false} otherwise.
1914 */
1915 private boolean isLocalOrAnonymousClass() {
1916 // JVM Spec 4.7.7: A class must have an EnclosingMethod
1917 // attribute if and only if it is a local class or an
1918 // anonymous class.
1919 return hasEnclosingMethodInfo();
1920 }
1921
1922 private boolean hasEnclosingMethodInfo() {
1923 Object[] enclosingInfo = getEnclosingMethod0();
1924 if (enclosingInfo != null) {
1925 EnclosingMethodInfo.validate(enclosingInfo);
1926 return true;
1927 }
1928 return false;
1929 }
1930
1931 /**
1932 * Returns an array containing {@code Class} objects representing all
1933 * the public classes and interfaces that are members of the class
1934 * represented by this {@code Class} object. This includes public
1935 * class and interface members inherited from superclasses and public class
1936 * and interface members declared by the class. This method returns an
1937 * array of length 0 if this {@code Class} object has no public member
1938 * classes or interfaces. This method also returns an array of length 0 if
1939 * this {@code Class} object represents a primitive type, an array
1940 * class, or void.
1941 *
1942 * @return the array of {@code Class} objects representing the public
1943 * members of this class
1944 * @since 1.1
1945 */
1946 public Class<?>[] getClasses() {
1947 List<Class<?>> list = new ArrayList<>();
1948 Class<?> currentClass = Class.this;
1949 while (currentClass != null) {
1950 for (Class<?> m : currentClass.getDeclaredClasses()) {
1951 if (Modifier.isPublic(m.getModifiers())) {
1952 list.add(m);
1953 }
1954 }
1955 currentClass = currentClass.getSuperclass();
1956 }
1957 return list.toArray(EMPTY_CLASS_ARRAY);
1958 }
1959
1960
1961 /**
1962 * Returns an array containing {@code Field} objects reflecting all
1963 * the accessible public fields of the class or interface represented by
1964 * this {@code Class} object.
1965 *
1966 * <p> If this {@code Class} object represents a class or interface with
1967 * no accessible public fields, then this method returns an array of length
1968 * 0.
1969 *
1970 * <p> If this {@code Class} object represents a class, then this method
1971 * returns the public fields of the class and of all its superclasses and
1972 * superinterfaces.
1973 *
1974 * <p> If this {@code Class} object represents an interface, then this
1975 * method returns the fields of the interface and of all its
1976 * superinterfaces.
1977 *
1978 * <p> If this {@code Class} object represents an array type, a primitive
1979 * type, or void, then this method returns an array of length 0.
1980 *
1981 * <p> The elements in the returned array are not sorted and are not in any
1982 * particular order.
1983 *
1984 * @return the array of {@code Field} objects representing the
1985 * public fields
1986 *
1987 * @since 1.1
1988 * @jls 8.2 Class Members
1989 * @jls 8.3 Field Declarations
1990 */
1991 public Field[] getFields() {
1992 return copyFields(privateGetPublicFields());
1993 }
1994
1995
1996 /**
1997 * Returns an array containing {@code Method} objects reflecting all the
1998 * public methods of the class or interface represented by this {@code
1999 * Class} object, including those declared by the class or interface and
2000 * those inherited from superclasses and superinterfaces.
2001 *
2002 * <p> If this {@code Class} object represents an array type, then the
2003 * returned array has a {@code Method} object for each of the public
2004 * methods inherited by the array type from {@code Object}. It does not
2005 * contain a {@code Method} object for {@code clone()}.
2006 *
2007 * <p> If this {@code Class} object represents an interface then the
2008 * returned array does not contain any implicitly declared methods from
2009 * {@code Object}. Therefore, if no methods are explicitly declared in
2010 * this interface or any of its superinterfaces then the returned array
2011 * has length 0. (Note that a {@code Class} object which represents a class
2012 * always has public methods, inherited from {@code Object}.)
2013 *
2014 * <p> The returned array never contains methods with names {@value
2015 * ConstantDescs#INIT_NAME} or {@value ConstantDescs#CLASS_INIT_NAME}.
2016 *
2017 * <p> The elements in the returned array are not sorted and are not in any
2018 * particular order.
2019 *
2020 * <p> Generally, the result is computed as with the following 4 step algorithm.
2021 * Let C be the class or interface represented by this {@code Class} object:
2022 * <ol>
2023 * <li> A union of methods is composed of:
2024 * <ol type="a">
2025 * <li> C's declared public instance and static methods as returned by
2026 * {@link #getDeclaredMethods()} and filtered to include only public
2027 * methods.</li>
2028 * <li> If C is a class other than {@code Object}, then include the result
2029 * of invoking this algorithm recursively on the superclass of C.</li>
2030 * <li> Include the results of invoking this algorithm recursively on all
2031 * direct superinterfaces of C, but include only instance methods.</li>
2032 * </ol></li>
2033 * <li> Union from step 1 is partitioned into subsets of methods with same
2034 * signature (name, parameter types) and return type.</li>
2035 * <li> Within each such subset only the most specific methods are selected.
2036 * Let method M be a method from a set of methods with same signature
2037 * and return type. M is most specific if there is no such method
2038 * N != M from the same set, such that N is more specific than M.
2039 * N is more specific than M if:
2040 * <ol type="a">
2041 * <li> N is declared by a class and M is declared by an interface; or</li>
2042 * <li> N and M are both declared by classes or both by interfaces and
2043 * N's declaring type is the same as or a subtype of M's declaring type
2044 * (clearly, if M's and N's declaring types are the same type, then
2045 * M and N are the same method).</li>
2046 * </ol></li>
2047 * <li> The result of this algorithm is the union of all selected methods from
2048 * step 3.</li>
2049 * </ol>
2050 *
2051 * @apiNote There may be more than one method with a particular name
2052 * and parameter types in a class because while the Java language forbids a
2053 * class to declare multiple methods with the same signature but different
2054 * return types, the Java virtual machine does not. This
2055 * increased flexibility in the virtual machine can be used to
2056 * implement various language features. For example, covariant
2057 * returns can be implemented with {@linkplain
2058 * java.lang.reflect.Method#isBridge bridge methods}; the bridge
2059 * method and the overriding method would have the same
2060 * signature but different return types.
2061 *
2062 * @return the array of {@code Method} objects representing the
2063 * public methods of this class
2064 *
2065 * @jls 8.2 Class Members
2066 * @jls 8.4 Method Declarations
2067 * @since 1.1
2068 */
2069 public Method[] getMethods() {
2070 return copyMethods(privateGetPublicMethods());
2071 }
2072
2073
2074 /**
2075 * Returns an array containing {@code Constructor} objects reflecting
2076 * all the public constructors of the class represented by this
2077 * {@code Class} object. An array of length 0 is returned if the
2078 * class has no public constructors, or if the class is an array class, or
2079 * if the class reflects a primitive type or void.
2080 *
2081 * @apiNote
2082 * While this method returns an array of {@code
2083 * Constructor<T>} objects (that is an array of constructors from
2084 * this class), the return type of this method is {@code
2085 * Constructor<?>[]} and <em>not</em> {@code Constructor<T>[]} as
2086 * might be expected. This less informative return type is
2087 * necessary since after being returned from this method, the
2088 * array could be modified to hold {@code Constructor} objects for
2089 * different classes, which would violate the type guarantees of
2090 * {@code Constructor<T>[]}.
2091 *
2092 * @return the array of {@code Constructor} objects representing the
2093 * public constructors of this class
2094 *
2095 * @see #getDeclaredConstructors()
2096 * @since 1.1
2097 */
2098 public Constructor<?>[] getConstructors() {
2099 return copyConstructors(privateGetDeclaredConstructors(true));
2100 }
2101
2102
2103 /**
2104 * Returns a {@code Field} object that reflects the specified public member
2105 * field of the class or interface represented by this {@code Class}
2106 * object. The {@code name} parameter is a {@code String} specifying the
2107 * simple name of the desired field.
2108 *
2109 * <p> The field to be reflected is determined by the algorithm that
2110 * follows. Let C be the class or interface represented by this {@code Class} object:
2111 *
2112 * <OL>
2113 * <LI> If C declares a public field with the name specified, that is the
2114 * field to be reflected.</LI>
2115 * <LI> If no field was found in step 1 above, this algorithm is applied
2116 * recursively to each direct superinterface of C. The direct
2117 * superinterfaces are searched in the order they were declared.</LI>
2118 * <LI> If no field was found in steps 1 and 2 above, and C has a
2119 * superclass S, then this algorithm is invoked recursively upon S.
2120 * If C has no superclass, then a {@code NoSuchFieldException}
2121 * is thrown.</LI>
2122 * </OL>
2123 *
2124 * <p> If this {@code Class} object represents an array type, then this
2125 * method does not find the {@code length} field of the array type.
2126 *
2127 * @param name the field name
2128 * @return the {@code Field} object of this class specified by
2129 * {@code name}
2130 * @throws NoSuchFieldException if a field with the specified name is
2131 * not found.
2132 * @throws NullPointerException if {@code name} is {@code null}
2133 *
2134 * @since 1.1
2135 * @jls 8.2 Class Members
2136 * @jls 8.3 Field Declarations
2137 */
2138 public Field getField(String name) throws NoSuchFieldException {
2139 Objects.requireNonNull(name);
2140 Field field = getField0(name);
2141 if (field == null) {
2142 throw new NoSuchFieldException(name);
2143 }
2144 return getReflectionFactory().copyField(field);
2145 }
2146
2147
2148 /**
2149 * Returns a {@code Method} object that reflects the specified public
2150 * member method of the class or interface represented by this
2151 * {@code Class} object. The {@code name} parameter is a
2152 * {@code String} specifying the simple name of the desired method. The
2153 * {@code parameterTypes} parameter is an array of {@code Class}
2154 * objects that identify the method's formal parameter types, in declared
2155 * order. If {@code parameterTypes} is {@code null}, it is
2156 * treated as if it were an empty array.
2157 *
2158 * <p> If this {@code Class} object represents an array type, then this
2159 * method finds any public method inherited by the array type from
2160 * {@code Object} except method {@code clone()}.
2161 *
2162 * <p> If this {@code Class} object represents an interface then this
2163 * method does not find any implicitly declared method from
2164 * {@code Object}. Therefore, if no methods are explicitly declared in
2165 * this interface or any of its superinterfaces, then this method does not
2166 * find any method.
2167 *
2168 * <p> This method does not find any method with name {@value
2169 * ConstantDescs#INIT_NAME} or {@value ConstantDescs#CLASS_INIT_NAME}.
2170 *
2171 * <p> Generally, the method to be reflected is determined by the 4 step
2172 * algorithm that follows.
2173 * Let C be the class or interface represented by this {@code Class} object:
2174 * <ol>
2175 * <li> A union of methods is composed of:
2176 * <ol type="a">
2177 * <li> C's declared public instance and static methods as returned by
2178 * {@link #getDeclaredMethods()} and filtered to include only public
2179 * methods that match given {@code name} and {@code parameterTypes}</li>
2180 * <li> If C is a class other than {@code Object}, then include the result
2181 * of invoking this algorithm recursively on the superclass of C.</li>
2182 * <li> Include the results of invoking this algorithm recursively on all
2183 * direct superinterfaces of C, but include only instance methods.</li>
2184 * </ol></li>
2185 * <li> This union is partitioned into subsets of methods with same
2186 * return type (the selection of methods from step 1 also guarantees that
2187 * they have the same method name and parameter types).</li>
2188 * <li> Within each such subset only the most specific methods are selected.
2189 * Let method M be a method from a set of methods with same VM
2190 * signature (return type, name, parameter types).
2191 * M is most specific if there is no such method N != M from the same
2192 * set, such that N is more specific than M. N is more specific than M
2193 * if:
2194 * <ol type="a">
2195 * <li> N is declared by a class and M is declared by an interface; or</li>
2196 * <li> N and M are both declared by classes or both by interfaces and
2197 * N's declaring type is the same as or a subtype of M's declaring type
2198 * (clearly, if M's and N's declaring types are the same type, then
2199 * M and N are the same method).</li>
2200 * </ol></li>
2201 * <li> The result of this algorithm is chosen arbitrarily from the methods
2202 * with most specific return type among all selected methods from step 3.
2203 * Let R be a return type of a method M from the set of all selected methods
2204 * from step 3. M is a method with most specific return type if there is
2205 * no such method N != M from the same set, having return type S != R,
2206 * such that S is a subtype of R as determined by
2207 * R.class.{@link #isAssignableFrom}(S.class).
2208 * </ol>
2209 *
2210 * @apiNote There may be more than one method with matching name and
2211 * parameter types in a class because while the Java language forbids a
2212 * class to declare multiple methods with the same signature but different
2213 * return types, the Java virtual machine does not. This
2214 * increased flexibility in the virtual machine can be used to
2215 * implement various language features. For example, covariant
2216 * returns can be implemented with {@linkplain
2217 * java.lang.reflect.Method#isBridge bridge methods}; the bridge
2218 * method and the overriding method would have the same
2219 * signature but different return types. This method would return the
2220 * overriding method as it would have a more specific return type.
2221 *
2222 * @param name the name of the method
2223 * @param parameterTypes the list of parameters
2224 * @return the {@code Method} object that matches the specified
2225 * {@code name} and {@code parameterTypes}
2226 * @throws NoSuchMethodException if a matching method is not found
2227 * or if the name is {@value ConstantDescs#INIT_NAME} or
2228 * {@value ConstantDescs#CLASS_INIT_NAME}.
2229 * @throws NullPointerException if {@code name} is {@code null}
2230 *
2231 * @jls 8.2 Class Members
2232 * @jls 8.4 Method Declarations
2233 * @since 1.1
2234 */
2235 public Method getMethod(String name, Class<?>... parameterTypes)
2236 throws NoSuchMethodException {
2237 Objects.requireNonNull(name);
2238 Method method = getMethod0(name, parameterTypes);
2239 if (method == null) {
2240 throw new NoSuchMethodException(methodToString(name, parameterTypes));
2241 }
2242 return getReflectionFactory().copyMethod(method);
2243 }
2244
2245 /**
2246 * Returns a {@code Constructor} object that reflects the specified
2247 * public constructor of the class represented by this {@code Class}
2248 * object. The {@code parameterTypes} parameter is an array of
2249 * {@code Class} objects that identify the constructor's formal
2250 * parameter types, in declared order.
2251 *
2252 * If this {@code Class} object represents an inner class
2253 * declared in a non-static context, the formal parameter types
2254 * include the explicit enclosing instance as the first parameter.
2255 *
2256 * <p> The constructor to reflect is the public constructor of the class
2257 * represented by this {@code Class} object whose formal parameter
2258 * types match those specified by {@code parameterTypes}.
2259 *
2260 * @param parameterTypes the parameter array
2261 * @return the {@code Constructor} object of the public constructor that
2262 * matches the specified {@code parameterTypes}
2263 * @throws NoSuchMethodException if a matching constructor is not found,
2264 * including when this {@code Class} object represents
2265 * an interface, a primitive type, an array class, or void.
2266 *
2267 * @see #getDeclaredConstructor(Class[])
2268 * @since 1.1
2269 */
2270 public Constructor<T> getConstructor(Class<?>... parameterTypes)
2271 throws NoSuchMethodException {
2272 return getReflectionFactory().copyConstructor(
2273 getConstructor0(parameterTypes, Member.PUBLIC));
2274 }
2275
2276
2277 /**
2278 * Returns an array of {@code Class} objects reflecting all the
2279 * classes and interfaces declared as members of the class represented by
2280 * this {@code Class} object. This includes public, protected, default
2281 * (package) access, and private classes and interfaces declared by the
2282 * class, but excludes inherited classes and interfaces. This method
2283 * returns an array of length 0 if the class declares no classes or
2284 * interfaces as members, or if this {@code Class} object represents a
2285 * primitive type, an array class, or void.
2286 *
2287 * @return the array of {@code Class} objects representing all the
2288 * declared members of this class
2289 *
2290 * @since 1.1
2291 * @jls 8.5 Member Class and Interface Declarations
2292 */
2293 public Class<?>[] getDeclaredClasses() {
2294 return getDeclaredClasses0();
2295 }
2296
2297
2298 /**
2299 * Returns an array of {@code Field} objects reflecting all the fields
2300 * declared by the class or interface represented by this
2301 * {@code Class} object. This includes public, protected, default
2302 * (package) access, and private fields, but excludes inherited fields.
2303 *
2304 * <p> If this {@code Class} object represents a class or interface with no
2305 * declared fields, then this method returns an array of length 0.
2306 *
2307 * <p> If this {@code Class} object represents an array type, a primitive
2308 * type, or void, then this method returns an array of length 0.
2309 *
2310 * <p> The elements in the returned array are not sorted and are not in any
2311 * particular order.
2312 *
2313 * @return the array of {@code Field} objects representing all the
2314 * declared fields of this class
2315 *
2316 * @since 1.1
2317 * @jls 8.2 Class Members
2318 * @jls 8.3 Field Declarations
2319 */
2320 public Field[] getDeclaredFields() {
2321 return copyFields(privateGetDeclaredFields(false));
2322 }
2323
2324 /**
2325 * Returns an array of {@code RecordComponent} objects representing all the
2326 * record components of this record class, or {@code null} if this class is
2327 * not a record class.
2328 *
2329 * <p> The components are returned in the same order that they are declared
2330 * in the record header. The array is empty if this record class has no
2331 * components. If the class is not a record class, that is {@link
2332 * #isRecord()} returns {@code false}, then this method returns {@code null}.
2333 * Conversely, if {@link #isRecord()} returns {@code true}, then this method
2334 * returns a non-null value.
2335 *
2336 * @apiNote
2337 * <p> The following method can be used to find the record canonical constructor:
2338 *
2339 * {@snippet lang="java" :
2340 * static <T extends Record> Constructor<T> getCanonicalConstructor(Class<T> cls)
2341 * throws NoSuchMethodException {
2342 * Class<?>[] paramTypes =
2343 * Arrays.stream(cls.getRecordComponents())
2344 * .map(RecordComponent::getType)
2345 * .toArray(Class<?>[]::new);
2346 * return cls.getDeclaredConstructor(paramTypes);
2347 * }}
2348 *
2349 * @return An array of {@code RecordComponent} objects representing all the
2350 * record components of this record class, or {@code null} if this
2351 * class is not a record class
2352 *
2353 * @jls 8.10 Record Classes
2354 * @since 16
2355 */
2356 public RecordComponent[] getRecordComponents() {
2357 if (!isRecord()) {
2358 return null;
2359 }
2360 return getRecordComponents0();
2361 }
2362
2363 /**
2364 * Returns an array containing {@code Method} objects reflecting all the
2365 * declared methods of the class or interface represented by this {@code
2366 * Class} object, including public, protected, default (package)
2367 * access, and private methods, but excluding inherited methods.
2368 * The declared methods may include methods <em>not</em> in the
2369 * source of the class or interface, including {@linkplain
2370 * Method#isBridge bridge methods} and other {@linkplain
2371 * Executable#isSynthetic synthetic} methods added by compilers.
2372 *
2373 * <p> If this {@code Class} object represents a class or interface that
2374 * has multiple declared methods with the same name and parameter types,
2375 * but different return types, then the returned array has a {@code Method}
2376 * object for each such method.
2377 *
2378 * <p> If this {@code Class} object represents a class or interface that
2379 * has a class initialization method {@value ConstantDescs#CLASS_INIT_NAME},
2380 * then the returned array does <em>not</em> have a corresponding {@code
2381 * Method} object.
2382 *
2383 * <p> If this {@code Class} object represents a class or interface with no
2384 * declared methods, then the returned array has length 0.
2385 *
2386 * <p> If this {@code Class} object represents an array type, a primitive
2387 * type, or void, then the returned array has length 0.
2388 *
2389 * <p> The elements in the returned array are not sorted and are not in any
2390 * particular order.
2391 *
2392 * @return the array of {@code Method} objects representing all the
2393 * declared methods of this class
2394 *
2395 * @jls 8.2 Class Members
2396 * @jls 8.4 Method Declarations
2397 * @see <a
2398 * href="{@docRoot}/java.base/java/lang/reflect/package-summary.html#LanguageJvmModel">Java
2399 * programming language and JVM modeling in core reflection</a>
2400 * @since 1.1
2401 */
2402 public Method[] getDeclaredMethods() {
2403 return copyMethods(privateGetDeclaredMethods(false));
2404 }
2405
2406 /**
2407 * Returns an array of {@code Constructor} objects reflecting all the
2408 * constructors implicitly or explicitly declared by the class represented by this
2409 * {@code Class} object. These are public, protected, default
2410 * (package) access, and private constructors. The elements in the array
2411 * returned are not sorted and are not in any particular order. If the
2412 * class has a default constructor (JLS {@jls 8.8.9}), it is included in the returned array.
2413 * If a record class has a canonical constructor (JLS {@jls
2414 * 8.10.4.1}, {@jls 8.10.4.2}), it is included in the returned array.
2415 *
2416 * This method returns an array of length 0 if this {@code Class}
2417 * object represents an interface, a primitive type, an array class, or
2418 * void.
2419 *
2420 * @return the array of {@code Constructor} objects representing all the
2421 * declared constructors of this class
2422 *
2423 * @since 1.1
2424 * @see #getConstructors()
2425 * @jls 8.8 Constructor Declarations
2426 */
2427 public Constructor<?>[] getDeclaredConstructors() {
2428 return copyConstructors(privateGetDeclaredConstructors(false));
2429 }
2430
2431
2432 /**
2433 * Returns a {@code Field} object that reflects the specified declared
2434 * field of the class or interface represented by this {@code Class}
2435 * object. The {@code name} parameter is a {@code String} that specifies
2436 * the simple name of the desired field.
2437 *
2438 * <p> If this {@code Class} object represents an array type, then this
2439 * method does not find the {@code length} field of the array type.
2440 *
2441 * @param name the name of the field
2442 * @return the {@code Field} object for the specified field in this
2443 * class
2444 * @throws NoSuchFieldException if a field with the specified name is
2445 * not found.
2446 * @throws NullPointerException if {@code name} is {@code null}
2447 *
2448 * @since 1.1
2449 * @jls 8.2 Class Members
2450 * @jls 8.3 Field Declarations
2451 */
2452 public Field getDeclaredField(String name) throws NoSuchFieldException {
2453 Objects.requireNonNull(name);
2454 Field field = searchFields(privateGetDeclaredFields(false), name);
2455 if (field == null) {
2456 throw new NoSuchFieldException(name);
2457 }
2458 return getReflectionFactory().copyField(field);
2459 }
2460
2461
2462 /**
2463 * Returns a {@code Method} object that reflects the specified
2464 * declared method of the class or interface represented by this
2465 * {@code Class} object. The {@code name} parameter is a
2466 * {@code String} that specifies the simple name of the desired
2467 * method, and the {@code parameterTypes} parameter is an array of
2468 * {@code Class} objects that identify the method's formal parameter
2469 * types, in declared order. If more than one method with the same
2470 * parameter types is declared in a class, and one of these methods has a
2471 * return type that is more specific than any of the others, that method is
2472 * returned; otherwise one of the methods is chosen arbitrarily. If the
2473 * name is {@value ConstantDescs#INIT_NAME} or {@value
2474 * ConstantDescs#CLASS_INIT_NAME} a {@code NoSuchMethodException}
2475 * is raised.
2476 *
2477 * <p> If this {@code Class} object represents an array type, then this
2478 * method does not find the {@code clone()} method.
2479 *
2480 * @param name the name of the method
2481 * @param parameterTypes the parameter array
2482 * @return the {@code Method} object for the method of this class
2483 * matching the specified name and parameters
2484 * @throws NoSuchMethodException if a matching method is not found.
2485 * @throws NullPointerException if {@code name} is {@code null}
2486 *
2487 * @jls 8.2 Class Members
2488 * @jls 8.4 Method Declarations
2489 * @since 1.1
2490 */
2491 public Method getDeclaredMethod(String name, Class<?>... parameterTypes)
2492 throws NoSuchMethodException {
2493 Objects.requireNonNull(name);
2494 Method method = searchMethods(privateGetDeclaredMethods(false), name, parameterTypes);
2495 if (method == null) {
2496 throw new NoSuchMethodException(methodToString(name, parameterTypes));
2497 }
2498 return getReflectionFactory().copyMethod(method);
2499 }
2500
2501 /**
2502 * Returns the list of {@code Method} objects for the declared public
2503 * methods of this class or interface that have the specified method name
2504 * and parameter types.
2505 *
2506 * @param name the name of the method
2507 * @param parameterTypes the parameter array
2508 * @return the list of {@code Method} objects for the public methods of
2509 * this class matching the specified name and parameters
2510 */
2511 List<Method> getDeclaredPublicMethods(String name, Class<?>... parameterTypes) {
2512 Method[] methods = privateGetDeclaredMethods(/* publicOnly */ true);
2513 ReflectionFactory factory = getReflectionFactory();
2514 List<Method> result = new ArrayList<>();
2515 for (Method method : methods) {
2516 if (method.getName().equals(name)
2517 && Arrays.equals(
2518 factory.getExecutableSharedParameterTypes(method),
2519 parameterTypes)) {
2520 result.add(factory.copyMethod(method));
2521 }
2522 }
2523 return result;
2524 }
2525
2526 /**
2527 * Returns the most specific {@code Method} object of this class, super class or
2528 * interface that have the specified method name and parameter types.
2529 *
2530 * @param publicOnly true if only public methods are examined, otherwise all methods
2531 * @param name the name of the method
2532 * @param parameterTypes the parameter array
2533 * @return the {@code Method} object for the method found from this class matching
2534 * the specified name and parameters, or null if not found
2535 */
2536 Method findMethod(boolean publicOnly, String name, Class<?>... parameterTypes) {
2537 PublicMethods.MethodList res = getMethodsRecursive(name, parameterTypes, true, publicOnly);
2538 return res == null ? null : getReflectionFactory().copyMethod(res.getMostSpecific());
2539 }
2540
2541 /**
2542 * Returns a {@code Constructor} object that reflects the specified
2543 * constructor of the class represented by this
2544 * {@code Class} object. The {@code parameterTypes} parameter is
2545 * an array of {@code Class} objects that identify the constructor's
2546 * formal parameter types, in declared order.
2547 *
2548 * If this {@code Class} object represents an inner class
2549 * declared in a non-static context, the formal parameter types
2550 * include the explicit enclosing instance as the first parameter.
2551 *
2552 * @param parameterTypes the parameter array
2553 * @return The {@code Constructor} object for the constructor with the
2554 * specified parameter list
2555 * @throws NoSuchMethodException if a matching constructor is not found,
2556 * including when this {@code Class} object represents
2557 * an interface, a primitive type, an array class, or void.
2558 *
2559 * @see #getConstructor(Class[])
2560 * @since 1.1
2561 */
2562 public Constructor<T> getDeclaredConstructor(Class<?>... parameterTypes)
2563 throws NoSuchMethodException {
2564 return getReflectionFactory().copyConstructor(
2565 getConstructor0(parameterTypes, Member.DECLARED));
2566 }
2567
2568 /**
2569 * Finds a resource with a given name.
2570 *
2571 * <p> If this class is in a named {@link Module Module} then this method
2572 * will attempt to find the resource in the module. This is done by
2573 * delegating to the module's class loader {@link
2574 * ClassLoader#findResource(String,String) findResource(String,String)}
2575 * method, invoking it with the module name and the absolute name of the
2576 * resource. Resources in named modules are subject to the rules for
2577 * encapsulation specified in the {@code Module} {@link
2578 * Module#getResourceAsStream getResourceAsStream} method and so this
2579 * method returns {@code null} when the resource is a
2580 * non-"{@code .class}" resource in a package that is not open to the
2581 * caller's module.
2582 *
2583 * <p> Otherwise, if this class is not in a named module then the rules for
2584 * searching resources associated with a given class are implemented by the
2585 * defining {@linkplain ClassLoader class loader} of the class. This method
2586 * delegates to this {@code Class} object's class loader.
2587 * If this {@code Class} object was loaded by the bootstrap class loader,
2588 * the method delegates to {@link ClassLoader#getSystemResourceAsStream}.
2589 *
2590 * <p> Before delegation, an absolute resource name is constructed from the
2591 * given resource name using this algorithm:
2592 *
2593 * <ul>
2594 *
2595 * <li> If the {@code name} begins with a {@code '/'}
2596 * (<code>'\u002f'</code>), then the absolute name of the resource is the
2597 * portion of the {@code name} following the {@code '/'}.
2598 *
2599 * <li> Otherwise, the absolute name is of the following form:
2600 *
2601 * <blockquote>
2602 * {@code modified_package_name/name}
2603 * </blockquote>
2604 *
2605 * <p> Where the {@code modified_package_name} is the package name of this
2606 * object with {@code '/'} substituted for {@code '.'}
2607 * (<code>'\u002e'</code>).
2608 *
2609 * </ul>
2610 *
2611 * @param name name of the desired resource
2612 * @return A {@link java.io.InputStream} object; {@code null} if no
2613 * resource with this name is found, or the resource is in a package
2614 * that is not {@linkplain Module#isOpen(String, Module) open} to at
2615 * least the caller module.
2616 * @throws NullPointerException If {@code name} is {@code null}
2617 *
2618 * @see Module#getResourceAsStream(String)
2619 * @since 1.1
2620 */
2621 @CallerSensitive
2622 public InputStream getResourceAsStream(String name) {
2623 name = resolveName(name);
2624
2625 Module thisModule = getModule();
2626 if (thisModule.isNamed()) {
2627 // check if resource can be located by caller
2628 if (Resources.canEncapsulate(name)
2629 && !isOpenToCaller(name, Reflection.getCallerClass())) {
2630 return null;
2631 }
2632
2633 // resource not encapsulated or in package open to caller
2634 String mn = thisModule.getName();
2635 ClassLoader cl = classLoader;
2636 try {
2637
2638 // special-case built-in class loaders to avoid the
2639 // need for a URL connection
2640 if (cl == null) {
2641 return BootLoader.findResourceAsStream(mn, name);
2642 } else if (cl instanceof BuiltinClassLoader bcl) {
2643 return bcl.findResourceAsStream(mn, name);
2644 } else {
2645 URL url = cl.findResource(mn, name);
2646 return (url != null) ? url.openStream() : null;
2647 }
2648
2649 } catch (IOException | SecurityException e) {
2650 return null;
2651 }
2652 }
2653
2654 // unnamed module
2655 ClassLoader cl = classLoader;
2656 if (cl == null) {
2657 return ClassLoader.getSystemResourceAsStream(name);
2658 } else {
2659 return cl.getResourceAsStream(name);
2660 }
2661 }
2662
2663 /**
2664 * Finds a resource with a given name.
2665 *
2666 * <p> If this class is in a named {@link Module Module} then this method
2667 * will attempt to find the resource in the module. This is done by
2668 * delegating to the module's class loader {@link
2669 * ClassLoader#findResource(String,String) findResource(String,String)}
2670 * method, invoking it with the module name and the absolute name of the
2671 * resource. Resources in named modules are subject to the rules for
2672 * encapsulation specified in the {@code Module} {@link
2673 * Module#getResourceAsStream getResourceAsStream} method and so this
2674 * method returns {@code null} when the resource is a
2675 * non-"{@code .class}" resource in a package that is not open to the
2676 * caller's module.
2677 *
2678 * <p> Otherwise, if this class is not in a named module then the rules for
2679 * searching resources associated with a given class are implemented by the
2680 * defining {@linkplain ClassLoader class loader} of the class. This method
2681 * delegates to this {@code Class} object's class loader.
2682 * If this {@code Class} object was loaded by the bootstrap class loader,
2683 * the method delegates to {@link ClassLoader#getSystemResource}.
2684 *
2685 * <p> Before delegation, an absolute resource name is constructed from the
2686 * given resource name using this algorithm:
2687 *
2688 * <ul>
2689 *
2690 * <li> If the {@code name} begins with a {@code '/'}
2691 * (<code>'\u002f'</code>), then the absolute name of the resource is the
2692 * portion of the {@code name} following the {@code '/'}.
2693 *
2694 * <li> Otherwise, the absolute name is of the following form:
2695 *
2696 * <blockquote>
2697 * {@code modified_package_name/name}
2698 * </blockquote>
2699 *
2700 * <p> Where the {@code modified_package_name} is the package name of this
2701 * object with {@code '/'} substituted for {@code '.'}
2702 * (<code>'\u002e'</code>).
2703 *
2704 * </ul>
2705 *
2706 * @param name name of the desired resource
2707 * @return A {@link java.net.URL} object; {@code null} if no resource with
2708 * this name is found, the resource cannot be located by a URL, or the
2709 * resource is in a package that is not
2710 * {@linkplain Module#isOpen(String, Module) open} to at least the caller
2711 * module.
2712 * @throws NullPointerException If {@code name} is {@code null}
2713 * @since 1.1
2714 */
2715 @CallerSensitive
2716 public URL getResource(String name) {
2717 name = resolveName(name);
2718
2719 Module thisModule = getModule();
2720 if (thisModule.isNamed()) {
2721 // check if resource can be located by caller
2722 if (Resources.canEncapsulate(name)
2723 && !isOpenToCaller(name, Reflection.getCallerClass())) {
2724 return null;
2725 }
2726
2727 // resource not encapsulated or in package open to caller
2728 String mn = thisModule.getName();
2729 ClassLoader cl = classLoader;
2730 try {
2731 if (cl == null) {
2732 return BootLoader.findResource(mn, name);
2733 } else {
2734 return cl.findResource(mn, name);
2735 }
2736 } catch (IOException ioe) {
2737 return null;
2738 }
2739 }
2740
2741 // unnamed module
2742 ClassLoader cl = classLoader;
2743 if (cl == null) {
2744 return ClassLoader.getSystemResource(name);
2745 } else {
2746 return cl.getResource(name);
2747 }
2748 }
2749
2750 /**
2751 * Returns true if a resource with the given name can be located by the
2752 * given caller. All resources in a module can be located by code in
2753 * the module. For other callers, then the package needs to be open to
2754 * the caller.
2755 */
2756 private boolean isOpenToCaller(String name, Class<?> caller) {
2757 // assert getModule().isNamed();
2758 Module thisModule = getModule();
2759 Module callerModule = (caller != null) ? caller.getModule() : null;
2760 if (callerModule != thisModule) {
2761 String pn = Resources.toPackageName(name);
2762 if (thisModule.getDescriptor().packages().contains(pn)) {
2763 if (callerModule == null) {
2764 // no caller, return true if the package is open to all modules
2765 return thisModule.isOpen(pn);
2766 }
2767 if (!thisModule.isOpen(pn, callerModule)) {
2768 // package not open to caller
2769 return false;
2770 }
2771 }
2772 }
2773 return true;
2774 }
2775
2776 private transient final ProtectionDomain protectionDomain;
2777
2778 /** Holder for the protection domain returned when the internal domain is null */
2779 private static class Holder {
2780 private static final ProtectionDomain allPermDomain;
2781 static {
2782 Permissions perms = new Permissions();
2783 perms.add(new AllPermission());
2784 allPermDomain = new ProtectionDomain(null, perms);
2785 }
2786 }
2787
2788 /**
2789 * Returns the {@code ProtectionDomain} of this class.
2790 *
2791 * @return the ProtectionDomain of this class
2792 *
2793 * @see java.security.ProtectionDomain
2794 * @since 1.2
2795 */
2796 public ProtectionDomain getProtectionDomain() {
2797 if (protectionDomain == null) {
2798 return Holder.allPermDomain;
2799 } else {
2800 return protectionDomain;
2801 }
2802 }
2803
2804 /*
2805 * Returns the Class object for the named primitive type. Type parameter T
2806 * avoids redundant casts for trusted code.
2807 */
2808 static native <T> Class<T> getPrimitiveClass(String name);
2809
2810 /**
2811 * Add a package name prefix if the name is not absolute. Remove leading "/"
2812 * if name is absolute
2813 */
2814 private String resolveName(String name) {
2815 if (!name.startsWith("/")) {
2816 String baseName = getPackageName();
2817 if (!baseName.isEmpty()) {
2818 int len = baseName.length() + 1 + name.length();
2819 StringBuilder sb = new StringBuilder(len);
2820 name = sb.append(baseName.replace('.', '/'))
2821 .append('/')
2822 .append(name)
2823 .toString();
2824 }
2825 } else {
2826 name = name.substring(1);
2827 }
2828 return name;
2829 }
2830
2831 /**
2832 * Atomic operations support.
2833 */
2834 private static class Atomic {
2835 // initialize Unsafe machinery here, since we need to call Class.class instance method
2836 // and have to avoid calling it in the static initializer of the Class class...
2837 private static final Unsafe unsafe = Unsafe.getUnsafe();
2838 // offset of Class.reflectionData instance field
2839 private static final long reflectionDataOffset
2840 = unsafe.objectFieldOffset(Class.class, "reflectionData");
2841 // offset of Class.annotationType instance field
2842 private static final long annotationTypeOffset
2843 = unsafe.objectFieldOffset(Class.class, "annotationType");
2844 // offset of Class.annotationData instance field
2845 private static final long annotationDataOffset
2846 = unsafe.objectFieldOffset(Class.class, "annotationData");
2847
2848 static <T> boolean casReflectionData(Class<?> clazz,
2849 SoftReference<ReflectionData<T>> oldData,
2850 SoftReference<ReflectionData<T>> newData) {
2851 return unsafe.compareAndSetReference(clazz, reflectionDataOffset, oldData, newData);
2852 }
2853
2854 static boolean casAnnotationType(Class<?> clazz,
2855 AnnotationType oldType,
2856 AnnotationType newType) {
2857 return unsafe.compareAndSetReference(clazz, annotationTypeOffset, oldType, newType);
2858 }
2859
2860 static boolean casAnnotationData(Class<?> clazz,
2861 AnnotationData oldData,
2862 AnnotationData newData) {
2863 return unsafe.compareAndSetReference(clazz, annotationDataOffset, oldData, newData);
2864 }
2865 }
2866
2867 /**
2868 * Reflection support.
2869 */
2870
2871 // Reflection data caches various derived names and reflective members. Cached
2872 // values may be invalidated when JVM TI RedefineClasses() is called
2873 private static class ReflectionData<T> {
2874 volatile Field[] declaredFields;
2875 volatile Field[] publicFields;
2876 volatile Method[] declaredMethods;
2877 volatile Method[] publicMethods;
2878 volatile Constructor<T>[] declaredConstructors;
2879 volatile Constructor<T>[] publicConstructors;
2880 // Intermediate results for getFields and getMethods
2881 volatile Field[] declaredPublicFields;
2882 volatile Method[] declaredPublicMethods;
2883 volatile Class<?>[] interfaces;
2884
2885 // Cached names
2886 String simpleName;
2887 String canonicalName;
2888 static final String NULL_SENTINEL = new String();
2889
2890 // Value of classRedefinedCount when we created this ReflectionData instance
2891 final int redefinedCount;
2892
2893 ReflectionData(int redefinedCount) {
2894 this.redefinedCount = redefinedCount;
2895 }
2896 }
2897
2898 private transient volatile SoftReference<ReflectionData<T>> reflectionData;
2899
2900 // Incremented by the VM on each call to JVM TI RedefineClasses()
2901 // that redefines this class or a superclass.
2902 private transient volatile int classRedefinedCount;
2903
2904 // Lazily create and cache ReflectionData
2905 private ReflectionData<T> reflectionData() {
2906 SoftReference<ReflectionData<T>> reflectionData = this.reflectionData;
2907 int classRedefinedCount = this.classRedefinedCount;
2908 ReflectionData<T> rd;
2909 if (reflectionData != null &&
2910 (rd = reflectionData.get()) != null &&
2911 rd.redefinedCount == classRedefinedCount) {
2912 return rd;
2913 }
2914 // else no SoftReference or cleared SoftReference or stale ReflectionData
2915 // -> create and replace new instance
2916 return newReflectionData(reflectionData, classRedefinedCount);
2917 }
2918
2919 private ReflectionData<T> newReflectionData(SoftReference<ReflectionData<T>> oldReflectionData,
2920 int classRedefinedCount) {
2921 while (true) {
2922 ReflectionData<T> rd = new ReflectionData<>(classRedefinedCount);
2923 // try to CAS it...
2924 if (Atomic.casReflectionData(this, oldReflectionData, new SoftReference<>(rd))) {
2925 return rd;
2926 }
2927 // else retry
2928 oldReflectionData = this.reflectionData;
2929 classRedefinedCount = this.classRedefinedCount;
2930 if (oldReflectionData != null &&
2931 (rd = oldReflectionData.get()) != null &&
2932 rd.redefinedCount == classRedefinedCount) {
2933 return rd;
2934 }
2935 }
2936 }
2937
2938 // Generic signature handling
2939 private native String getGenericSignature0();
2940
2941 // Generic info repository; lazily initialized
2942 private transient volatile ClassRepository genericInfo;
2943
2944 // accessor for factory
2945 private GenericsFactory getFactory() {
2946 // create scope and factory
2947 return CoreReflectionFactory.make(this, ClassScope.make(this));
2948 }
2949
2950 // accessor for generic info repository;
2951 // generic info is lazily initialized
2952 private ClassRepository getGenericInfo() {
2953 ClassRepository genericInfo = this.genericInfo;
2954 if (genericInfo == null) {
2955 String signature = getGenericSignature0();
2956 if (signature == null) {
2957 genericInfo = ClassRepository.NONE;
2958 } else {
2959 genericInfo = ClassRepository.make(signature, getFactory());
2960 }
2961 this.genericInfo = genericInfo;
2962 }
2963 return (genericInfo != ClassRepository.NONE) ? genericInfo : null;
2964 }
2965
2966 // Annotations handling
2967 native byte[] getRawAnnotations();
2968 // Since 1.8
2969 native byte[] getRawTypeAnnotations();
2970 static byte[] getExecutableTypeAnnotationBytes(Executable ex) {
2971 return getReflectionFactory().getExecutableTypeAnnotationBytes(ex);
2972 }
2973
2974 native ConstantPool getConstantPool();
2975
2976 //
2977 //
2978 // java.lang.reflect.Field handling
2979 //
2980 //
2981
2982 // Returns an array of "root" fields. These Field objects must NOT
2983 // be propagated to the outside world, but must instead be copied
2984 // via ReflectionFactory.copyField.
2985 private Field[] privateGetDeclaredFields(boolean publicOnly) {
2986 Field[] res;
2987 ReflectionData<T> rd = reflectionData();
2988 res = publicOnly ? rd.declaredPublicFields : rd.declaredFields;
2989 if (res != null) return res;
2990 // No cached value available; request value from VM
2991 res = Reflection.filterFields(this, getDeclaredFields0(publicOnly));
2992 if (publicOnly) {
2993 rd.declaredPublicFields = res;
2994 } else {
2995 rd.declaredFields = res;
2996 }
2997 return res;
2998 }
2999
3000 // Returns an array of "root" fields. These Field objects must NOT
3001 // be propagated to the outside world, but must instead be copied
3002 // via ReflectionFactory.copyField.
3003 private Field[] privateGetPublicFields() {
3004 Field[] res;
3005 ReflectionData<T> rd = reflectionData();
3006 res = rd.publicFields;
3007 if (res != null) return res;
3008
3009 // Use a linked hash set to ensure order is preserved and
3010 // fields from common super interfaces are not duplicated
3011 LinkedHashSet<Field> fields = new LinkedHashSet<>();
3012
3013 // Local fields
3014 addAll(fields, privateGetDeclaredFields(true));
3015
3016 // Direct superinterfaces, recursively
3017 for (Class<?> si : getInterfaces(/* cloneArray */ false)) {
3018 addAll(fields, si.privateGetPublicFields());
3019 }
3020
3021 // Direct superclass, recursively
3022 Class<?> sc = getSuperclass();
3023 if (sc != null) {
3024 addAll(fields, sc.privateGetPublicFields());
3025 }
3026
3027 res = fields.toArray(new Field[0]);
3028 rd.publicFields = res;
3029 return res;
3030 }
3031
3032 private static void addAll(Collection<Field> c, Field[] o) {
3033 for (Field f : o) {
3034 c.add(f);
3035 }
3036 }
3037
3038
3039 //
3040 //
3041 // java.lang.reflect.Constructor handling
3042 //
3043 //
3044
3045 // Returns an array of "root" constructors. These Constructor
3046 // objects must NOT be propagated to the outside world, but must
3047 // instead be copied via ReflectionFactory.copyConstructor.
3048 private Constructor<T>[] privateGetDeclaredConstructors(boolean publicOnly) {
3049 Constructor<T>[] res;
3050 ReflectionData<T> rd = reflectionData();
3051 res = publicOnly ? rd.publicConstructors : rd.declaredConstructors;
3052 if (res != null) return res;
3053 // No cached value available; request value from VM
3054 if (isInterface()) {
3055 @SuppressWarnings("unchecked")
3056 Constructor<T>[] temporaryRes = (Constructor<T>[]) new Constructor<?>[0];
3057 res = temporaryRes;
3058 } else {
3059 res = getDeclaredConstructors0(publicOnly);
3060 }
3061 if (publicOnly) {
3062 rd.publicConstructors = res;
3063 } else {
3064 rd.declaredConstructors = res;
3065 }
3066 return res;
3067 }
3068
3069 //
3070 //
3071 // java.lang.reflect.Method handling
3072 //
3073 //
3074
3075 // Returns an array of "root" methods. These Method objects must NOT
3076 // be propagated to the outside world, but must instead be copied
3077 // via ReflectionFactory.copyMethod.
3078 private Method[] privateGetDeclaredMethods(boolean publicOnly) {
3079 Method[] res;
3080 ReflectionData<T> rd = reflectionData();
3081 res = publicOnly ? rd.declaredPublicMethods : rd.declaredMethods;
3082 if (res != null) return res;
3083 // No cached value available; request value from VM
3084 res = Reflection.filterMethods(this, getDeclaredMethods0(publicOnly));
3085 if (publicOnly) {
3086 rd.declaredPublicMethods = res;
3087 } else {
3088 rd.declaredMethods = res;
3089 }
3090 return res;
3091 }
3092
3093 // Returns an array of "root" methods. These Method objects must NOT
3094 // be propagated to the outside world, but must instead be copied
3095 // via ReflectionFactory.copyMethod.
3096 private Method[] privateGetPublicMethods() {
3097 Method[] res;
3098 ReflectionData<T> rd = reflectionData();
3099 res = rd.publicMethods;
3100 if (res != null) return res;
3101
3102 // No cached value available; compute value recursively.
3103 // Start by fetching public declared methods...
3104 PublicMethods pms = new PublicMethods();
3105 for (Method m : privateGetDeclaredMethods(/* publicOnly */ true)) {
3106 pms.merge(m);
3107 }
3108 // ...then recur over superclass methods...
3109 Class<?> sc = getSuperclass();
3110 if (sc != null) {
3111 for (Method m : sc.privateGetPublicMethods()) {
3112 pms.merge(m);
3113 }
3114 }
3115 // ...and finally over direct superinterfaces.
3116 for (Class<?> intf : getInterfaces(/* cloneArray */ false)) {
3117 for (Method m : intf.privateGetPublicMethods()) {
3118 // static interface methods are not inherited
3119 if (!Modifier.isStatic(m.getModifiers())) {
3120 pms.merge(m);
3121 }
3122 }
3123 }
3124
3125 res = pms.toArray();
3126 rd.publicMethods = res;
3127 return res;
3128 }
3129
3130
3131 //
3132 // Helpers for fetchers of one field, method, or constructor
3133 //
3134
3135 // This method does not copy the returned Field object!
3136 private static Field searchFields(Field[] fields, String name) {
3137 for (Field field : fields) {
3138 if (field.getName().equals(name)) {
3139 return field;
3140 }
3141 }
3142 return null;
3143 }
3144
3145 // Returns a "root" Field object. This Field object must NOT
3146 // be propagated to the outside world, but must instead be copied
3147 // via ReflectionFactory.copyField.
3148 private Field getField0(String name) {
3149 // Note: the intent is that the search algorithm this routine
3150 // uses be equivalent to the ordering imposed by
3151 // privateGetPublicFields(). It fetches only the declared
3152 // public fields for each class, however, to reduce the number
3153 // of Field objects which have to be created for the common
3154 // case where the field being requested is declared in the
3155 // class which is being queried.
3156 Field res;
3157 // Search declared public fields
3158 if ((res = searchFields(privateGetDeclaredFields(true), name)) != null) {
3159 return res;
3160 }
3161 // Direct superinterfaces, recursively
3162 Class<?>[] interfaces = getInterfaces(/* cloneArray */ false);
3163 for (Class<?> c : interfaces) {
3164 if ((res = c.getField0(name)) != null) {
3165 return res;
3166 }
3167 }
3168 // Direct superclass, recursively
3169 if (!isInterface()) {
3170 Class<?> c = getSuperclass();
3171 if (c != null) {
3172 if ((res = c.getField0(name)) != null) {
3173 return res;
3174 }
3175 }
3176 }
3177 return null;
3178 }
3179
3180 // This method does not copy the returned Method object!
3181 private static Method searchMethods(Method[] methods,
3182 String name,
3183 Class<?>[] parameterTypes)
3184 {
3185 ReflectionFactory fact = getReflectionFactory();
3186 Method res = null;
3187 for (Method m : methods) {
3188 if (m.getName().equals(name)
3189 && arrayContentsEq(parameterTypes,
3190 fact.getExecutableSharedParameterTypes(m))
3191 && (res == null
3192 || (res.getReturnType() != m.getReturnType()
3193 && res.getReturnType().isAssignableFrom(m.getReturnType()))))
3194 res = m;
3195 }
3196 return res;
3197 }
3198
3199 private static final Class<?>[] EMPTY_CLASS_ARRAY = new Class<?>[0];
3200
3201 // Returns a "root" Method object. This Method object must NOT
3202 // be propagated to the outside world, but must instead be copied
3203 // via ReflectionFactory.copyMethod.
3204 private Method getMethod0(String name, Class<?>[] parameterTypes) {
3205 PublicMethods.MethodList res = getMethodsRecursive(
3206 name,
3207 parameterTypes == null ? EMPTY_CLASS_ARRAY : parameterTypes,
3208 /* includeStatic */ true, /* publicOnly */ true);
3209 return res == null ? null : res.getMostSpecific();
3210 }
3211
3212 // Returns a list of "root" Method objects. These Method objects must NOT
3213 // be propagated to the outside world, but must instead be copied
3214 // via ReflectionFactory.copyMethod.
3215 private PublicMethods.MethodList getMethodsRecursive(String name,
3216 Class<?>[] parameterTypes,
3217 boolean includeStatic,
3218 boolean publicOnly) {
3219 // 1st check declared methods
3220 Method[] methods = privateGetDeclaredMethods(publicOnly);
3221 PublicMethods.MethodList res = PublicMethods.MethodList
3222 .filter(methods, name, parameterTypes, includeStatic);
3223 // if there is at least one match among declared methods, we need not
3224 // search any further as such match surely overrides matching methods
3225 // declared in superclass(es) or interface(s).
3226 if (res != null) {
3227 return res;
3228 }
3229
3230 // if there was no match among declared methods,
3231 // we must consult the superclass (if any) recursively...
3232 Class<?> sc = getSuperclass();
3233 if (sc != null) {
3234 res = sc.getMethodsRecursive(name, parameterTypes, includeStatic, publicOnly);
3235 }
3236
3237 // ...and coalesce the superclass methods with methods obtained
3238 // from directly implemented interfaces excluding static methods...
3239 for (Class<?> intf : getInterfaces(/* cloneArray */ false)) {
3240 res = PublicMethods.MethodList.merge(
3241 res, intf.getMethodsRecursive(name, parameterTypes, /* includeStatic */ false, publicOnly));
3242 }
3243
3244 return res;
3245 }
3246
3247 // Returns a "root" Constructor object. This Constructor object must NOT
3248 // be propagated to the outside world, but must instead be copied
3249 // via ReflectionFactory.copyConstructor.
3250 private Constructor<T> getConstructor0(Class<?>[] parameterTypes,
3251 int which) throws NoSuchMethodException
3252 {
3253 ReflectionFactory fact = getReflectionFactory();
3254 Constructor<T>[] constructors = privateGetDeclaredConstructors((which == Member.PUBLIC));
3255 for (Constructor<T> constructor : constructors) {
3256 if (arrayContentsEq(parameterTypes,
3257 fact.getExecutableSharedParameterTypes(constructor))) {
3258 return constructor;
3259 }
3260 }
3261 throw new NoSuchMethodException(methodToString("<init>", parameterTypes));
3262 }
3263
3264 //
3265 // Other helpers and base implementation
3266 //
3267
3268 private static boolean arrayContentsEq(Object[] a1, Object[] a2) {
3269 if (a1 == null) {
3270 return a2 == null || a2.length == 0;
3271 }
3272
3273 if (a2 == null) {
3274 return a1.length == 0;
3275 }
3276
3277 if (a1.length != a2.length) {
3278 return false;
3279 }
3280
3281 for (int i = 0; i < a1.length; i++) {
3282 if (a1[i] != a2[i]) {
3283 return false;
3284 }
3285 }
3286
3287 return true;
3288 }
3289
3290 private static Field[] copyFields(Field[] arg) {
3291 Field[] out = new Field[arg.length];
3292 ReflectionFactory fact = getReflectionFactory();
3293 for (int i = 0; i < arg.length; i++) {
3294 out[i] = fact.copyField(arg[i]);
3295 }
3296 return out;
3297 }
3298
3299 private static Method[] copyMethods(Method[] arg) {
3300 Method[] out = new Method[arg.length];
3301 ReflectionFactory fact = getReflectionFactory();
3302 for (int i = 0; i < arg.length; i++) {
3303 out[i] = fact.copyMethod(arg[i]);
3304 }
3305 return out;
3306 }
3307
3308 private static <U> Constructor<U>[] copyConstructors(Constructor<U>[] arg) {
3309 Constructor<U>[] out = arg.clone();
3310 ReflectionFactory fact = getReflectionFactory();
3311 for (int i = 0; i < out.length; i++) {
3312 out[i] = fact.copyConstructor(out[i]);
3313 }
3314 return out;
3315 }
3316
3317 private native Field[] getDeclaredFields0(boolean publicOnly);
3318 private native Method[] getDeclaredMethods0(boolean publicOnly);
3319 private native Constructor<T>[] getDeclaredConstructors0(boolean publicOnly);
3320 private native Class<?>[] getDeclaredClasses0();
3321
3322 /*
3323 * Returns an array containing the components of the Record attribute,
3324 * or null if the attribute is not present.
3325 *
3326 * Note that this method returns non-null array on a class with
3327 * the Record attribute even if this class is not a record.
3328 */
3329 private native RecordComponent[] getRecordComponents0();
3330 private native boolean isRecord0();
3331
3332 /**
3333 * Helper method to get the method name from arguments.
3334 */
3335 private String methodToString(String name, Class<?>[] argTypes) {
3336 return getName() + '.' + name +
3337 ((argTypes == null || argTypes.length == 0) ?
3338 "()" :
3339 Arrays.stream(argTypes)
3340 .map(c -> c == null ? "null" : c.getName())
3341 .collect(Collectors.joining(",", "(", ")")));
3342 }
3343
3344 /** use serialVersionUID from JDK 1.1 for interoperability */
3345 @java.io.Serial
3346 private static final long serialVersionUID = 3206093459760846163L;
3347
3348
3349 /**
3350 * Class Class is special cased within the Serialization Stream Protocol.
3351 *
3352 * A Class instance is written initially into an ObjectOutputStream in the
3353 * following format:
3354 * <pre>
3355 * {@code TC_CLASS} ClassDescriptor
3356 * A ClassDescriptor is a special cased serialization of
3357 * a {@code java.io.ObjectStreamClass} instance.
3358 * </pre>
3359 * A new handle is generated for the initial time the class descriptor
3360 * is written into the stream. Future references to the class descriptor
3361 * are written as references to the initial class descriptor instance.
3362 *
3363 * @see java.io.ObjectStreamClass
3364 */
3365 @java.io.Serial
3366 private static final ObjectStreamField[] serialPersistentFields =
3367 new ObjectStreamField[0];
3368
3369
3370 /**
3371 * Returns the assertion status that would be assigned to this
3372 * class if it were to be initialized at the time this method is invoked.
3373 * If this class has had its assertion status set, the most recent
3374 * setting will be returned; otherwise, if any package default assertion
3375 * status pertains to this class, the most recent setting for the most
3376 * specific pertinent package default assertion status is returned;
3377 * otherwise, if this class is not a system class (i.e., it has a
3378 * class loader) its class loader's default assertion status is returned;
3379 * otherwise, the system class default assertion status is returned.
3380 *
3381 * @apiNote
3382 * Few programmers will have any need for this method; it is provided
3383 * for the benefit of the JDK itself. (It allows a class to determine at
3384 * the time that it is initialized whether assertions should be enabled.)
3385 * Note that this method is not guaranteed to return the actual
3386 * assertion status that was (or will be) associated with the specified
3387 * class when it was (or will be) initialized.
3388 *
3389 * @return the desired assertion status of the specified class.
3390 * @see java.lang.ClassLoader#setClassAssertionStatus
3391 * @see java.lang.ClassLoader#setPackageAssertionStatus
3392 * @see java.lang.ClassLoader#setDefaultAssertionStatus
3393 * @since 1.4
3394 */
3395 public boolean desiredAssertionStatus() {
3396 ClassLoader loader = classLoader;
3397 // If the loader is null this is a system class, so ask the VM
3398 if (loader == null)
3399 return desiredAssertionStatus0(this);
3400
3401 // If the classloader has been initialized with the assertion
3402 // directives, ask it. Otherwise, ask the VM.
3403 synchronized(loader.assertionLock) {
3404 if (loader.classAssertionStatus != null) {
3405 return loader.desiredAssertionStatus(getName());
3406 }
3407 }
3408 return desiredAssertionStatus0(this);
3409 }
3410
3411 // Retrieves the desired assertion status of this class from the VM
3412 private static native boolean desiredAssertionStatus0(Class<?> clazz);
3413
3414 /**
3415 * Returns true if and only if this class was declared as an enum in the
3416 * source code.
3417 *
3418 * Note that {@link java.lang.Enum} is not itself an enum class.
3419 *
3420 * Also note that if an enum constant is declared with a class body,
3421 * the class of that enum constant object is an anonymous class
3422 * and <em>not</em> the class of the declaring enum class. The
3423 * {@link Enum#getDeclaringClass} method of an enum constant can
3424 * be used to get the class of the enum class declaring the
3425 * constant.
3426 *
3427 * @return true if and only if this class was declared as an enum in the
3428 * source code
3429 * @since 1.5
3430 * @jls 8.9.1 Enum Constants
3431 */
3432 public boolean isEnum() {
3433 // An enum must both directly extend java.lang.Enum and have
3434 // the ENUM bit set; classes for specialized enum constants
3435 // don't do the former.
3436 return (this.getModifiers() & ENUM) != 0 &&
3437 this.getSuperclass() == java.lang.Enum.class;
3438 }
3439
3440 /**
3441 * Returns {@code true} if and only if this class is a record class.
3442 *
3443 * <p> The {@linkplain #getSuperclass() direct superclass} of a record
3444 * class is {@code java.lang.Record}. A record class is {@linkplain
3445 * Modifier#FINAL final}. A record class has (possibly zero) record
3446 * components; {@link #getRecordComponents()} returns a non-null but
3447 * possibly empty value for a record.
3448 *
3449 * <p> Note that class {@link Record} is not a record class and thus
3450 * invoking this method on class {@code Record} returns {@code false}.
3451 *
3452 * @return true if and only if this class is a record class, otherwise false
3453 * @jls 8.10 Record Classes
3454 * @since 16
3455 */
3456 public boolean isRecord() {
3457 // this superclass and final modifier check is not strictly necessary
3458 // they are intrinsified and serve as a fast-path check
3459 return getSuperclass() == java.lang.Record.class &&
3460 (this.getModifiers() & Modifier.FINAL) != 0 &&
3461 isRecord0();
3462 }
3463
3464 // Fetches the factory for reflective objects
3465 private static ReflectionFactory getReflectionFactory() {
3466 var factory = reflectionFactory;
3467 if (factory != null) {
3468 return factory;
3469 }
3470 return reflectionFactory = ReflectionFactory.getReflectionFactory();
3471 }
3472 private static ReflectionFactory reflectionFactory;
3473
3474 /**
3475 * When CDS is enabled, the Class class may be aot-initialized. However,
3476 * we can't archive reflectionFactory, so we reset it to null, so it
3477 * will be allocated again at runtime.
3478 */
3479 private static void resetArchivedStates() {
3480 reflectionFactory = null;
3481 }
3482
3483 /**
3484 * Returns the elements of this enum class or null if this
3485 * Class object does not represent an enum class.
3486 *
3487 * @return an array containing the values comprising the enum class
3488 * represented by this {@code Class} object in the order they're
3489 * declared, or null if this {@code Class} object does not
3490 * represent an enum class
3491 * @since 1.5
3492 * @jls 8.9.1 Enum Constants
3493 */
3494 public T[] getEnumConstants() {
3495 T[] values = getEnumConstantsShared();
3496 return (values != null) ? values.clone() : null;
3497 }
3498
3499 /**
3500 * Returns the elements of this enum class or null if this
3501 * Class object does not represent an enum class;
3502 * identical to getEnumConstants except that the result is
3503 * uncloned, cached, and shared by all callers.
3504 */
3505 T[] getEnumConstantsShared() {
3506 T[] constants = enumConstants;
3507 if (constants == null) {
3508 if (!isEnum()) return null;
3509 try {
3510 final Method values = getMethod("values");
3511 values.setAccessible(true);
3512 @SuppressWarnings("unchecked")
3513 T[] temporaryConstants = (T[])values.invoke(null);
3514 enumConstants = constants = temporaryConstants;
3515 }
3516 // These can happen when users concoct enum-like classes
3517 // that don't comply with the enum spec.
3518 catch (InvocationTargetException | NoSuchMethodException |
3519 IllegalAccessException | NullPointerException |
3520 ClassCastException ex) { return null; }
3521 }
3522 return constants;
3523 }
3524 private transient volatile T[] enumConstants;
3525
3526 /**
3527 * Returns a map from simple name to enum constant. This package-private
3528 * method is used internally by Enum to implement
3529 * {@code public static <T extends Enum<T>> T valueOf(Class<T>, String)}
3530 * efficiently. Note that the map is returned by this method is
3531 * created lazily on first use. Typically it won't ever get created.
3532 */
3533 Map<String, T> enumConstantDirectory() {
3534 Map<String, T> directory = enumConstantDirectory;
3535 if (directory == null) {
3536 T[] universe = getEnumConstantsShared();
3537 if (universe == null)
3538 throw new IllegalArgumentException(
3539 getName() + " is not an enum class");
3540 directory = HashMap.newHashMap(universe.length);
3541 for (T constant : universe) {
3542 directory.put(((Enum<?>)constant).name(), constant);
3543 }
3544 enumConstantDirectory = directory;
3545 }
3546 return directory;
3547 }
3548 private transient volatile Map<String, T> enumConstantDirectory;
3549
3550 /**
3551 * Casts an object to the class or interface represented
3552 * by this {@code Class} object.
3553 *
3554 * @param obj the object to be cast
3555 * @return the object after casting, or null if obj is null
3556 *
3557 * @throws ClassCastException if the object is not
3558 * null and is not assignable to the type T.
3559 *
3560 * @since 1.5
3561 */
3562 @SuppressWarnings("unchecked")
3563 @IntrinsicCandidate
3564 public T cast(Object obj) {
3565 if (obj != null && !isInstance(obj))
3566 throw new ClassCastException(cannotCastMsg(obj));
3567 return (T) obj;
3568 }
3569
3570 private String cannotCastMsg(Object obj) {
3571 return "Cannot cast " + obj.getClass().getName() + " to " + getName();
3572 }
3573
3574 /**
3575 * Casts this {@code Class} object to represent a subclass of the class
3576 * represented by the specified class object. Checks that the cast
3577 * is valid, and throws a {@code ClassCastException} if it is not. If
3578 * this method succeeds, it always returns a reference to this {@code Class} object.
3579 *
3580 * <p>This method is useful when a client needs to "narrow" the type of
3581 * a {@code Class} object to pass it to an API that restricts the
3582 * {@code Class} objects that it is willing to accept. A cast would
3583 * generate a compile-time warning, as the correctness of the cast
3584 * could not be checked at runtime (because generic types are implemented
3585 * by erasure).
3586 *
3587 * @param <U> the type to cast this {@code Class} object to
3588 * @param clazz the class of the type to cast this {@code Class} object to
3589 * @return this {@code Class} object, cast to represent a subclass of
3590 * the specified class object.
3591 * @throws ClassCastException if this {@code Class} object does not
3592 * represent a subclass of the specified class (here "subclass" includes
3593 * the class itself).
3594 * @since 1.5
3595 */
3596 @SuppressWarnings("unchecked")
3597 public <U> Class<? extends U> asSubclass(Class<U> clazz) {
3598 if (clazz.isAssignableFrom(this))
3599 return (Class<? extends U>) this;
3600 else
3601 throw new ClassCastException(this.toString());
3602 }
3603
3604 /**
3605 * {@inheritDoc}
3606 * <p>Note that any annotation returned by this method is a
3607 * declaration annotation.
3608 *
3609 * @throws NullPointerException {@inheritDoc}
3610 * @since 1.5
3611 */
3612 @Override
3613 @SuppressWarnings("unchecked")
3614 public <A extends Annotation> A getAnnotation(Class<A> annotationClass) {
3615 Objects.requireNonNull(annotationClass);
3616
3617 return (A) annotationData().annotations.get(annotationClass);
3618 }
3619
3620 /**
3621 * {@inheritDoc}
3622 * @throws NullPointerException {@inheritDoc}
3623 * @since 1.5
3624 */
3625 @Override
3626 public boolean isAnnotationPresent(Class<? extends Annotation> annotationClass) {
3627 return GenericDeclaration.super.isAnnotationPresent(annotationClass);
3628 }
3629
3630 /**
3631 * {@inheritDoc}
3632 * <p>Note that any annotations returned by this method are
3633 * declaration annotations.
3634 *
3635 * @throws NullPointerException {@inheritDoc}
3636 * @since 1.8
3637 */
3638 @Override
3639 public <A extends Annotation> A[] getAnnotationsByType(Class<A> annotationClass) {
3640 Objects.requireNonNull(annotationClass);
3641
3642 AnnotationData annotationData = annotationData();
3643 return AnnotationSupport.getAssociatedAnnotations(annotationData.declaredAnnotations,
3644 this,
3645 annotationClass);
3646 }
3647
3648 /**
3649 * {@inheritDoc}
3650 * <p>Note that any annotations returned by this method are
3651 * declaration annotations.
3652 *
3653 * @since 1.5
3654 */
3655 @Override
3656 public Annotation[] getAnnotations() {
3657 return AnnotationParser.toArray(annotationData().annotations);
3658 }
3659
3660 /**
3661 * {@inheritDoc}
3662 * <p>Note that any annotation returned by this method is a
3663 * declaration annotation.
3664 *
3665 * @throws NullPointerException {@inheritDoc}
3666 * @since 1.8
3667 */
3668 @Override
3669 @SuppressWarnings("unchecked")
3670 public <A extends Annotation> A getDeclaredAnnotation(Class<A> annotationClass) {
3671 Objects.requireNonNull(annotationClass);
3672
3673 return (A) annotationData().declaredAnnotations.get(annotationClass);
3674 }
3675
3676 /**
3677 * {@inheritDoc}
3678 * <p>Note that any annotations returned by this method are
3679 * declaration annotations.
3680 *
3681 * @throws NullPointerException {@inheritDoc}
3682 * @since 1.8
3683 */
3684 @Override
3685 public <A extends Annotation> A[] getDeclaredAnnotationsByType(Class<A> annotationClass) {
3686 Objects.requireNonNull(annotationClass);
3687
3688 return AnnotationSupport.getDirectlyAndIndirectlyPresent(annotationData().declaredAnnotations,
3689 annotationClass);
3690 }
3691
3692 /**
3693 * {@inheritDoc}
3694 * <p>Note that any annotations returned by this method are
3695 * declaration annotations.
3696 *
3697 * @since 1.5
3698 */
3699 @Override
3700 public Annotation[] getDeclaredAnnotations() {
3701 return AnnotationParser.toArray(annotationData().declaredAnnotations);
3702 }
3703
3704 // annotation data that might get invalidated when JVM TI RedefineClasses() is called
3705 private static class AnnotationData {
3706 final Map<Class<? extends Annotation>, Annotation> annotations;
3707 final Map<Class<? extends Annotation>, Annotation> declaredAnnotations;
3708
3709 // Value of classRedefinedCount when we created this AnnotationData instance
3710 final int redefinedCount;
3711
3712 AnnotationData(Map<Class<? extends Annotation>, Annotation> annotations,
3713 Map<Class<? extends Annotation>, Annotation> declaredAnnotations,
3714 int redefinedCount) {
3715 this.annotations = annotations;
3716 this.declaredAnnotations = declaredAnnotations;
3717 this.redefinedCount = redefinedCount;
3718 }
3719 }
3720
3721 // Annotations cache
3722 @SuppressWarnings("UnusedDeclaration")
3723 private transient volatile AnnotationData annotationData;
3724
3725 private AnnotationData annotationData() {
3726 while (true) { // retry loop
3727 AnnotationData annotationData = this.annotationData;
3728 int classRedefinedCount = this.classRedefinedCount;
3729 if (annotationData != null &&
3730 annotationData.redefinedCount == classRedefinedCount) {
3731 return annotationData;
3732 }
3733 // null or stale annotationData -> optimistically create new instance
3734 AnnotationData newAnnotationData = createAnnotationData(classRedefinedCount);
3735 // try to install it
3736 if (Atomic.casAnnotationData(this, annotationData, newAnnotationData)) {
3737 // successfully installed new AnnotationData
3738 return newAnnotationData;
3739 }
3740 }
3741 }
3742
3743 private AnnotationData createAnnotationData(int classRedefinedCount) {
3744 Map<Class<? extends Annotation>, Annotation> declaredAnnotations =
3745 AnnotationParser.parseAnnotations(getRawAnnotations(), getConstantPool(), this);
3746 Class<?> superClass = getSuperclass();
3747 Map<Class<? extends Annotation>, Annotation> annotations = null;
3748 if (superClass != null) {
3749 Map<Class<? extends Annotation>, Annotation> superAnnotations =
3750 superClass.annotationData().annotations;
3751 for (Map.Entry<Class<? extends Annotation>, Annotation> e : superAnnotations.entrySet()) {
3752 Class<? extends Annotation> annotationClass = e.getKey();
3753 if (AnnotationType.getInstance(annotationClass).isInherited()) {
3754 if (annotations == null) { // lazy construction
3755 annotations = LinkedHashMap.newLinkedHashMap(Math.max(
3756 declaredAnnotations.size(),
3757 Math.min(12, declaredAnnotations.size() + superAnnotations.size())
3758 )
3759 );
3760 }
3761 annotations.put(annotationClass, e.getValue());
3762 }
3763 }
3764 }
3765 if (annotations == null) {
3766 // no inherited annotations -> share the Map with declaredAnnotations
3767 annotations = declaredAnnotations;
3768 } else {
3769 // at least one inherited annotation -> declared may override inherited
3770 annotations.putAll(declaredAnnotations);
3771 }
3772 return new AnnotationData(annotations, declaredAnnotations, classRedefinedCount);
3773 }
3774
3775 // Annotation interfaces cache their internal (AnnotationType) form
3776
3777 @SuppressWarnings("UnusedDeclaration")
3778 private transient volatile AnnotationType annotationType;
3779
3780 boolean casAnnotationType(AnnotationType oldType, AnnotationType newType) {
3781 return Atomic.casAnnotationType(this, oldType, newType);
3782 }
3783
3784 AnnotationType getAnnotationType() {
3785 return annotationType;
3786 }
3787
3788 Map<Class<? extends Annotation>, Annotation> getDeclaredAnnotationMap() {
3789 return annotationData().declaredAnnotations;
3790 }
3791
3792 /* Backing store of user-defined values pertaining to this class.
3793 * Maintained by the ClassValue class.
3794 */
3795 transient ClassValue.ClassValueMap classValueMap;
3796
3797 /**
3798 * Returns an {@code AnnotatedType} object that represents the use of a
3799 * type to specify the superclass of the entity represented by this {@code
3800 * Class} object. (The <em>use</em> of type Foo to specify the superclass
3801 * in '... extends Foo' is distinct from the <em>declaration</em> of class
3802 * Foo.)
3803 *
3804 * <p> If this {@code Class} object represents a class whose declaration
3805 * does not explicitly indicate an annotated superclass, then the return
3806 * value is an {@code AnnotatedType} object representing an element with no
3807 * annotations.
3808 *
3809 * <p> If this {@code Class} represents either the {@code Object} class, an
3810 * interface type, an array type, a primitive type, or void, the return
3811 * value is {@code null}.
3812 *
3813 * @return an object representing the superclass
3814 * @since 1.8
3815 */
3816 public AnnotatedType getAnnotatedSuperclass() {
3817 if (this == Object.class ||
3818 isInterface() ||
3819 isArray() ||
3820 isPrimitive() ||
3821 this == Void.TYPE) {
3822 return null;
3823 }
3824
3825 return TypeAnnotationParser.buildAnnotatedSuperclass(getRawTypeAnnotations(), getConstantPool(), this);
3826 }
3827
3828 /**
3829 * Returns an array of {@code AnnotatedType} objects that represent the use
3830 * of types to specify superinterfaces of the entity represented by this
3831 * {@code Class} object. (The <em>use</em> of type Foo to specify a
3832 * superinterface in '... implements Foo' is distinct from the
3833 * <em>declaration</em> of interface Foo.)
3834 *
3835 * <p> If this {@code Class} object represents a class, the return value is
3836 * an array containing objects representing the uses of interface types to
3837 * specify interfaces implemented by the class. The order of the objects in
3838 * the array corresponds to the order of the interface types used in the
3839 * 'implements' clause of the declaration of this {@code Class} object.
3840 *
3841 * <p> If this {@code Class} object represents an interface, the return
3842 * value is an array containing objects representing the uses of interface
3843 * types to specify interfaces directly extended by the interface. The
3844 * order of the objects in the array corresponds to the order of the
3845 * interface types used in the 'extends' clause of the declaration of this
3846 * {@code Class} object.
3847 *
3848 * <p> If this {@code Class} object represents a class or interface whose
3849 * declaration does not explicitly indicate any annotated superinterfaces,
3850 * the return value is an array of length 0.
3851 *
3852 * <p> If this {@code Class} object represents either the {@code Object}
3853 * class, an array type, a primitive type, or void, the return value is an
3854 * array of length 0.
3855 *
3856 * @return an array representing the superinterfaces
3857 * @since 1.8
3858 */
3859 public AnnotatedType[] getAnnotatedInterfaces() {
3860 return TypeAnnotationParser.buildAnnotatedInterfaces(getRawTypeAnnotations(), getConstantPool(), this);
3861 }
3862
3863 private native Class<?> getNestHost0();
3864
3865 /**
3866 * Returns the nest host of the <a href=#nest>nest</a> to which the class
3867 * or interface represented by this {@code Class} object belongs.
3868 * Every class and interface belongs to exactly one nest.
3869 *
3870 * If the nest host of this class or interface has previously
3871 * been determined, then this method returns the nest host.
3872 * If the nest host of this class or interface has
3873 * not previously been determined, then this method determines the nest
3874 * host using the algorithm of JVMS 5.4.4, and returns it.
3875 *
3876 * Often, a class or interface belongs to a nest consisting only of itself,
3877 * in which case this method returns {@code this} to indicate that the class
3878 * or interface is the nest host.
3879 *
3880 * <p>If this {@code Class} object represents a primitive type, an array type,
3881 * or {@code void}, then this method returns {@code this},
3882 * indicating that the represented entity belongs to the nest consisting only of
3883 * itself, and is the nest host.
3884 *
3885 * @return the nest host of this class or interface
3886 *
3887 * @since 11
3888 * @jvms 4.7.28 The {@code NestHost} Attribute
3889 * @jvms 4.7.29 The {@code NestMembers} Attribute
3890 * @jvms 5.4.4 Access Control
3891 */
3892 public Class<?> getNestHost() {
3893 if (isPrimitive() || isArray()) {
3894 return this;
3895 }
3896 return getNestHost0();
3897 }
3898
3899 /**
3900 * Determines if the given {@code Class} is a nestmate of the
3901 * class or interface represented by this {@code Class} object.
3902 * Two classes or interfaces are nestmates
3903 * if they have the same {@linkplain #getNestHost() nest host}.
3904 *
3905 * @param c the class to check
3906 * @return {@code true} if this class and {@code c} are members of
3907 * the same nest; and {@code false} otherwise.
3908 *
3909 * @since 11
3910 */
3911 public boolean isNestmateOf(Class<?> c) {
3912 if (this == c) {
3913 return true;
3914 }
3915 if (isPrimitive() || isArray() ||
3916 c.isPrimitive() || c.isArray()) {
3917 return false;
3918 }
3919
3920 return getNestHost() == c.getNestHost();
3921 }
3922
3923 private native Class<?>[] getNestMembers0();
3924
3925 /**
3926 * Returns an array containing {@code Class} objects representing all the
3927 * classes and interfaces that are members of the nest to which the class
3928 * or interface represented by this {@code Class} object belongs.
3929 *
3930 * First, this method obtains the {@linkplain #getNestHost() nest host},
3931 * {@code H}, of the nest to which the class or interface represented by
3932 * this {@code Class} object belongs. The zeroth element of the returned
3933 * array is {@code H}.
3934 *
3935 * Then, for each class or interface {@code C} which is recorded by {@code H}
3936 * as being a member of its nest, this method attempts to obtain the {@code Class}
3937 * object for {@code C} (using {@linkplain #getClassLoader() the defining class
3938 * loader} of the current {@code Class} object), and then obtains the
3939 * {@linkplain #getNestHost() nest host} of the nest to which {@code C} belongs.
3940 * The classes and interfaces which are recorded by {@code H} as being members
3941 * of its nest, and for which {@code H} can be determined as their nest host,
3942 * are indicated by subsequent elements of the returned array. The order of
3943 * such elements is unspecified. Duplicates are permitted.
3944 *
3945 * <p>If this {@code Class} object represents a primitive type, an array type,
3946 * or {@code void}, then this method returns a single-element array containing
3947 * {@code this}.
3948 *
3949 * @apiNote
3950 * The returned array includes only the nest members recorded in the {@code NestMembers}
3951 * attribute, and not any hidden classes that were added to the nest via
3952 * {@link MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
3953 * Lookup::defineHiddenClass}.
3954 *
3955 * @return an array of all classes and interfaces in the same nest as
3956 * this class or interface
3957 *
3958 * @since 11
3959 * @see #getNestHost()
3960 * @jvms 4.7.28 The {@code NestHost} Attribute
3961 * @jvms 4.7.29 The {@code NestMembers} Attribute
3962 */
3963 public Class<?>[] getNestMembers() {
3964 if (isPrimitive() || isArray()) {
3965 return new Class<?>[] { this };
3966 }
3967 Class<?>[] members = getNestMembers0();
3968 // Can't actually enable this due to bootstrapping issues
3969 // assert(members.length != 1 || members[0] == this); // expected invariant from VM
3970 return members;
3971 }
3972
3973 /**
3974 * Returns the descriptor string of the entity (class, interface, array class,
3975 * primitive type, or {@code void}) represented by this {@code Class} object.
3976 *
3977 * <p> If this {@code Class} object represents a class or interface,
3978 * not an array class, then:
3979 * <ul>
3980 * <li> If the class or interface is not {@linkplain Class#isHidden() hidden},
3981 * then the result is a field descriptor (JVMS {@jvms 4.3.2})
3982 * for the class or interface. Calling
3983 * {@link ClassDesc#ofDescriptor(String) ClassDesc::ofDescriptor}
3984 * with the result descriptor string produces a {@link ClassDesc ClassDesc}
3985 * describing this class or interface.
3986 * <li> If the class or interface is {@linkplain Class#isHidden() hidden},
3987 * then the result is a string of the form:
3988 * <blockquote>
3989 * {@code "L" +} <em>N</em> {@code + "." + <suffix> + ";"}
3990 * </blockquote>
3991 * where <em>N</em> is the {@linkplain ClassLoader##binary-name binary name}
3992 * encoded in internal form indicated by the {@code class} file passed to
3993 * {@link MethodHandles.Lookup#defineHiddenClass(byte[], boolean, MethodHandles.Lookup.ClassOption...)
3994 * Lookup::defineHiddenClass}, and {@code <suffix>} is an unqualified name.
3995 * A hidden class or interface has no {@linkplain ClassDesc nominal descriptor}.
3996 * The result string is not a type descriptor.
3997 * </ul>
3998 *
3999 * <p> If this {@code Class} object represents an array class, then
4000 * the result is a string consisting of one or more '{@code [}' characters
4001 * representing the depth of the array nesting, followed by the
4002 * descriptor string of the element type.
4003 * <ul>
4004 * <li> If the element type is not a {@linkplain Class#isHidden() hidden} class
4005 * or interface, then this array class can be described nominally.
4006 * Calling {@link ClassDesc#ofDescriptor(String) ClassDesc::ofDescriptor}
4007 * with the result descriptor string produces a {@link ClassDesc ClassDesc}
4008 * describing this array class.
4009 * <li> If the element type is a {@linkplain Class#isHidden() hidden} class or
4010 * interface, then this array class cannot be described nominally.
4011 * The result string is not a type descriptor.
4012 * </ul>
4013 *
4014 * <p> If this {@code Class} object represents a primitive type or
4015 * {@code void}, then the result is a field descriptor string which
4016 * is a one-letter code corresponding to a primitive type or {@code void}
4017 * ({@code "B", "C", "D", "F", "I", "J", "S", "Z", "V"}) (JVMS {@jvms 4.3.2}).
4018 *
4019 * @return the descriptor string for this {@code Class} object
4020 * @jvms 4.3.2 Field Descriptors
4021 * @since 12
4022 */
4023 @Override
4024 public String descriptorString() {
4025 if (isPrimitive())
4026 return Wrapper.forPrimitiveType(this).basicTypeString();
4027
4028 if (isArray()) {
4029 return "[".concat(componentType.descriptorString());
4030 } else if (isHidden()) {
4031 String name = getName();
4032 int index = name.indexOf('/');
4033 return new StringBuilder(name.length() + 2)
4034 .append('L')
4035 .append(name.substring(0, index).replace('.', '/'))
4036 .append('.')
4037 .append(name, index + 1, name.length())
4038 .append(';')
4039 .toString();
4040 } else {
4041 String name = getName().replace('.', '/');
4042 return StringConcatHelper.concat("L", name, ";");
4043 }
4044 }
4045
4046 /**
4047 * Returns the component type of this {@code Class}, if it describes
4048 * an array type, or {@code null} otherwise.
4049 *
4050 * @implSpec
4051 * Equivalent to {@link Class#getComponentType()}.
4052 *
4053 * @return a {@code Class} describing the component type, or {@code null}
4054 * if this {@code Class} does not describe an array type
4055 * @since 12
4056 */
4057 @Override
4058 public Class<?> componentType() {
4059 return getComponentType();
4060 }
4061
4062 /**
4063 * Returns a {@code Class} for an array type whose component type
4064 * is described by this {@linkplain Class}.
4065 *
4066 * @throws UnsupportedOperationException if this component type is {@linkplain
4067 * Void#TYPE void} or if the number of dimensions of the resulting array
4068 * type would exceed 255.
4069 * @return a {@code Class} describing the array type
4070 * @jvms 4.3.2 Field Descriptors
4071 * @jvms 4.4.1 The {@code CONSTANT_Class_info} Structure
4072 * @since 12
4073 */
4074 @Override
4075 public Class<?> arrayType() {
4076 try {
4077 return Array.newInstance(this, 0).getClass();
4078 } catch (IllegalArgumentException iae) {
4079 throw new UnsupportedOperationException(iae);
4080 }
4081 }
4082
4083 /**
4084 * Returns a nominal descriptor for this instance, if one can be
4085 * constructed, or an empty {@link Optional} if one cannot be.
4086 *
4087 * @return An {@link Optional} containing the resulting nominal descriptor,
4088 * or an empty {@link Optional} if one cannot be constructed.
4089 * @since 12
4090 */
4091 @Override
4092 public Optional<ClassDesc> describeConstable() {
4093 Class<?> c = isArray() ? elementType() : this;
4094 return c.isHidden() ? Optional.empty()
4095 : Optional.of(ConstantUtils.classDesc(this));
4096 }
4097
4098 /**
4099 * Returns {@code true} if and only if the underlying class is a hidden class.
4100 *
4101 * @return {@code true} if and only if this class is a hidden class.
4102 *
4103 * @since 15
4104 * @see MethodHandles.Lookup#defineHiddenClass
4105 * @see Class##hiddenClasses Hidden Classes
4106 */
4107 @IntrinsicCandidate
4108 public native boolean isHidden();
4109
4110 /**
4111 * Returns an array containing {@code Class} objects representing the
4112 * direct subinterfaces or subclasses permitted to extend or
4113 * implement this class or interface if it is sealed. The order of such elements
4114 * is unspecified. The array is empty if this sealed class or interface has no
4115 * permitted subclass. If this {@code Class} object represents a primitive type,
4116 * {@code void}, an array type, or a class or interface that is not sealed,
4117 * that is {@link #isSealed()} returns {@code false}, then this method returns {@code null}.
4118 * Conversely, if {@link #isSealed()} returns {@code true}, then this method
4119 * returns a non-null value.
4120 *
4121 * For each class or interface {@code C} which is recorded as a permitted
4122 * direct subinterface or subclass of this class or interface,
4123 * this method attempts to obtain the {@code Class}
4124 * object for {@code C} (using {@linkplain #getClassLoader() the defining class
4125 * loader} of the current {@code Class} object).
4126 * The {@code Class} objects which can be obtained and which are direct
4127 * subinterfaces or subclasses of this class or interface,
4128 * are indicated by elements of the returned array. If a {@code Class} object
4129 * cannot be obtained, it is silently ignored, and not included in the result
4130 * array.
4131 *
4132 * @return an array of {@code Class} objects of the permitted subclasses of this class
4133 * or interface, or {@code null} if this class or interface is not sealed.
4134 *
4135 * @jls 8.1 Class Declarations
4136 * @jls 9.1 Interface Declarations
4137 * @since 17
4138 */
4139 public Class<?>[] getPermittedSubclasses() {
4140 Class<?>[] subClasses;
4141 if (isArray() || isPrimitive() || (subClasses = getPermittedSubclasses0()) == null) {
4142 return null;
4143 }
4144 if (subClasses.length > 0) {
4145 if (Arrays.stream(subClasses).anyMatch(c -> !isDirectSubType(c))) {
4146 subClasses = Arrays.stream(subClasses)
4147 .filter(this::isDirectSubType)
4148 .toArray(s -> new Class<?>[s]);
4149 }
4150 }
4151 return subClasses;
4152 }
4153
4154 private boolean isDirectSubType(Class<?> c) {
4155 if (isInterface()) {
4156 for (Class<?> i : c.getInterfaces(/* cloneArray */ false)) {
4157 if (i == this) {
4158 return true;
4159 }
4160 }
4161 } else {
4162 return c.getSuperclass() == this;
4163 }
4164 return false;
4165 }
4166
4167 /**
4168 * Returns {@code true} if and only if this {@code Class} object represents
4169 * a sealed class or interface. If this {@code Class} object represents a
4170 * primitive type, {@code void}, or an array type, this method returns
4171 * {@code false}. A sealed class or interface has (possibly zero) permitted
4172 * subclasses; {@link #getPermittedSubclasses()} returns a non-null but
4173 * possibly empty value for a sealed class or interface.
4174 *
4175 * @return {@code true} if and only if this {@code Class} object represents
4176 * a sealed class or interface.
4177 *
4178 * @jls 8.1 Class Declarations
4179 * @jls 9.1 Interface Declarations
4180 * @since 17
4181 */
4182 public boolean isSealed() {
4183 if (isArray() || isPrimitive()) {
4184 return false;
4185 }
4186 return getPermittedSubclasses() != null;
4187 }
4188
4189 private native Class<?>[] getPermittedSubclasses0();
4190
4191 /*
4192 * Return the class's major and minor class file version packed into an int.
4193 * The high order 16 bits contain the class's minor version. The low order
4194 * 16 bits contain the class's major version.
4195 *
4196 * If the class is an array type then the class file version of its element
4197 * type is returned. If the class is a primitive type then the latest class
4198 * file major version is returned and zero is returned for the minor version.
4199 */
4200 /* package-private */
4201 int getClassFileVersion() {
4202 Class<?> c = isArray() ? elementType() : this;
4203 return c.getClassFileVersion0();
4204 }
4205
4206 private native int getClassFileVersion0();
4207
4208 /**
4209 * Return the access flags as they were in the class's bytecode, including
4210 * the original setting of ACC_SUPER.
4211 *
4212 * If this {@code Class} object represents a primitive type or
4213 * void, the flags are {@code PUBLIC}, {@code ABSTRACT}, and
4214 * {@code FINAL}.
4215 * If this {@code Class} object represents an array type, return 0.
4216 */
4217 int getClassFileAccessFlags() {
4218 return classFileAccessFlags;
4219 }
4220
4221 // Validates the length of the class name and throws an exception if it exceeds the maximum allowed length.
4222 private static void validateClassNameLength(String name) throws ClassNotFoundException {
4223 if (!ModifiedUtf.isValidLengthInConstantPool(name)) {
4224 throw new ClassNotFoundException(
4225 "Class name length exceeds limit of "
4226 + ModifiedUtf.CONSTANT_POOL_UTF8_MAX_BYTES
4227 + ": " + name.substring(0,256) + "...");
4228 }
4229 }
4230 }