1 /*
2 * Copyright (c) 1996, 2024, 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.reflect;
27
28 import jdk.internal.access.SharedSecrets;
29 import jdk.internal.misc.VM;
30 import jdk.internal.reflect.CallerSensitive;
31 import jdk.internal.reflect.CallerSensitiveAdapter;
32 import jdk.internal.reflect.MethodAccessor;
33 import jdk.internal.reflect.Reflection;
34 import jdk.internal.vm.annotation.ForceInline;
35 import jdk.internal.vm.annotation.IntrinsicCandidate;
36 import jdk.internal.vm.annotation.Stable;
37 import sun.reflect.annotation.ExceptionProxy;
38 import sun.reflect.annotation.TypeNotPresentExceptionProxy;
39 import sun.reflect.generics.repository.GenericDeclRepository;
40 import sun.reflect.generics.repository.MethodRepository;
41 import sun.reflect.generics.factory.CoreReflectionFactory;
42 import sun.reflect.generics.factory.GenericsFactory;
43 import sun.reflect.generics.scope.MethodScope;
44 import sun.reflect.annotation.AnnotationType;
45 import sun.reflect.annotation.AnnotationParser;
46 import java.lang.annotation.Annotation;
47 import java.lang.annotation.AnnotationFormatError;
48 import java.nio.ByteBuffer;
49 import java.util.StringJoiner;
50
51 /**
52 * A {@code Method} provides information about, and access to, a single method
53 * on a class or interface. The reflected method may be a class method
54 * or an instance method (including an abstract method).
55 *
56 * <p>A {@code Method} permits widening conversions to occur when matching the
57 * actual parameters to invoke with the underlying method's formal
58 * parameters, but it throws an {@code IllegalArgumentException} if a
59 * narrowing conversion would occur.
60 *
61 * @see Member
62 * @see java.lang.Class
63 * @see java.lang.Class#getMethods()
64 * @see java.lang.Class#getMethod(String, Class[])
65 * @see java.lang.Class#getDeclaredMethods()
66 * @see java.lang.Class#getDeclaredMethod(String, Class[])
67 *
68 * @author Kenneth Russell
69 * @author Nakul Saraiya
70 * @since 1.1
71 */
72 public final class Method extends Executable {
73 private final Class<?> clazz;
74 private final int slot;
75 // This is guaranteed to be interned by the VM in the 1.4
76 // reflection implementation
77 private final String name;
78 private final Class<?> returnType;
79 private final Class<?>[] parameterTypes;
80 private final Class<?>[] exceptionTypes;
81 private final int modifiers;
82 // Generics and annotations support
83 private final transient String signature;
84 // generic info repository; lazily initialized
85 private transient volatile MethodRepository genericInfo;
86 private final byte[] annotations;
87 private final byte[] parameterAnnotations;
88 private final byte[] annotationDefault;
89 @Stable
90 private MethodAccessor methodAccessor;
91 // For sharing of MethodAccessors. This branching structure is
92 // currently only two levels deep (i.e., one root Method and
93 // potentially many Method objects pointing to it.)
94 //
95 // If this branching structure would ever contain cycles, deadlocks can
96 // occur in annotation code.
97 private Method root;
98 // Hash code of this object
99 private int hash;
100
101 // Generics infrastructure
102 private String getGenericSignature() {return signature;}
103
104 // Accessor for factory
105 private GenericsFactory getFactory() {
106 // create scope and factory
107 return CoreReflectionFactory.make(this, MethodScope.make(this));
108 }
109
110 // Accessor for generic info repository
111 @Override
112 MethodRepository getGenericInfo() {
113 var genericInfo = this.genericInfo;
114 // lazily initialize repository if necessary
115 if (genericInfo == null) {
116 // create and cache generic info repository
117 genericInfo = MethodRepository.make(getGenericSignature(),
118 getFactory());
119 this.genericInfo = genericInfo;
120 }
121 return genericInfo; //return cached repository
122 }
123
124 /**
125 * Package-private constructor
126 */
127 Method(Class<?> declaringClass,
128 String name,
129 Class<?>[] parameterTypes,
130 Class<?> returnType,
131 Class<?>[] checkedExceptions,
132 int modifiers,
133 int slot,
134 String signature,
135 byte[] annotations,
136 byte[] parameterAnnotations,
137 byte[] annotationDefault) {
138 this.clazz = declaringClass;
139 this.name = name;
140 this.parameterTypes = parameterTypes;
141 this.returnType = returnType;
142 this.exceptionTypes = checkedExceptions;
143 this.modifiers = modifiers;
144 this.slot = slot;
145 this.signature = signature;
146 this.annotations = annotations;
147 this.parameterAnnotations = parameterAnnotations;
148 this.annotationDefault = annotationDefault;
149 }
150
151 /**
152 * Package-private routine (exposed to java.lang.Class via
153 * ReflectAccess) which returns a copy of this Method. The copy's
154 * "root" field points to this Method.
155 */
156 Method copy() {
157 // This routine enables sharing of MethodAccessor objects
158 // among Method objects which refer to the same underlying
159 // method in the VM. (All of this contortion is only necessary
160 // because of the "accessibility" bit in AccessibleObject,
161 // which implicitly requires that new java.lang.reflect
162 // objects be fabricated for each reflective call on Class
163 // objects.)
164 if (this.root != null)
165 throw new IllegalArgumentException("Can not copy a non-root Method");
166
167 Method res = new Method(clazz, name, parameterTypes, returnType,
168 exceptionTypes, modifiers, slot, signature,
169 annotations, parameterAnnotations, annotationDefault);
170 res.root = this;
171 // Might as well eagerly propagate this if already present
172 res.methodAccessor = methodAccessor;
173 return res;
174 }
175
176 /**
177 * @throws InaccessibleObjectException {@inheritDoc}
178 * @throws SecurityException {@inheritDoc}
179 */
180 @Override
181 @CallerSensitive
182 public void setAccessible(boolean flag) {
183 AccessibleObject.checkPermission();
184 if (flag) checkCanSetAccessible(Reflection.getCallerClass());
185 setAccessible0(flag);
186 }
187
188 @Override
189 void checkCanSetAccessible(Class<?> caller) {
190 checkCanSetAccessible(caller, clazz);
191 }
192
193 @Override
194 Method getRoot() {
195 return root;
196 }
197
198 @Override
199 boolean hasGenericInformation() {
200 return (getGenericSignature() != null);
201 }
202
203 @Override
204 byte[] getAnnotationBytes() {
205 return annotations;
206 }
207
208 /**
209 * Returns the {@code Class} object representing the class or interface
210 * that declares the method represented by this object.
211 */
212 @Override
213 public Class<?> getDeclaringClass() {
214 return clazz;
215 }
216
217 /**
218 * Returns the name of the method represented by this {@code Method}
219 * object, as a {@code String}.
220 */
221 @Override
222 public String getName() {
223 return name;
224 }
225
226 /**
227 * {@inheritDoc}
228 * @jls 8.4.3 Method Modifiers
229 */
230 @Override
231 public int getModifiers() {
232 return modifiers;
233 }
234
235 /**
236 * {@inheritDoc}
237 * @throws GenericSignatureFormatError {@inheritDoc}
238 * @since 1.5
239 * @jls 8.4.4 Generic Methods
240 */
241 @Override
242 @SuppressWarnings({"rawtypes", "unchecked"})
243 public TypeVariable<Method>[] getTypeParameters() {
244 if (getGenericSignature() != null)
245 return (TypeVariable<Method>[])getGenericInfo().getTypeParameters();
246 else
247 return (TypeVariable<Method>[])GenericDeclRepository.EMPTY_TYPE_VARS;
248 }
249
250 /**
251 * Returns a {@code Class} object that represents the formal return type
252 * of the method represented by this {@code Method} object.
253 *
254 * @return the return type for the method this object represents
255 */
256 public Class<?> getReturnType() {
257 return returnType;
258 }
259
260 /**
261 * Returns a {@code Type} object that represents the formal return
262 * type of the method represented by this {@code Method} object.
263 *
264 * <p>If the return type is a parameterized type,
265 * the {@code Type} object returned must accurately reflect
266 * the actual type arguments used in the source code.
267 *
268 * <p>If the return type is a type variable or a parameterized type, it
269 * is created. Otherwise, it is resolved.
270 *
271 * @return a {@code Type} object that represents the formal return
272 * type of the underlying method
273 * @throws GenericSignatureFormatError
274 * if the generic method signature does not conform to the format
275 * specified in
276 * <cite>The Java Virtual Machine Specification</cite>
277 * @throws TypeNotPresentException if the underlying method's
278 * return type refers to a non-existent class or interface declaration
279 * @throws MalformedParameterizedTypeException if the
280 * underlying method's return type refers to a parameterized
281 * type that cannot be instantiated for any reason
282 * @since 1.5
283 */
284 public Type getGenericReturnType() {
285 if (getGenericSignature() != null) {
286 return getGenericInfo().getReturnType();
287 } else { return getReturnType();}
288 }
289
290 @Override
291 Class<?>[] getSharedParameterTypes() {
292 return parameterTypes;
293 }
294
295 @Override
296 Class<?>[] getSharedExceptionTypes() {
297 return exceptionTypes;
298 }
299
300 /**
301 * {@inheritDoc}
302 */
303 @Override
304 public Class<?>[] getParameterTypes() {
305 return parameterTypes.length == 0 ? parameterTypes: parameterTypes.clone();
306 }
307
308 /**
309 * {@inheritDoc}
310 * @since 1.8
311 */
312 public int getParameterCount() { return parameterTypes.length; }
313
314
315 /**
316 * {@inheritDoc}
317 * @throws GenericSignatureFormatError {@inheritDoc}
318 * @throws TypeNotPresentException {@inheritDoc}
319 * @throws MalformedParameterizedTypeException {@inheritDoc}
320 * @since 1.5
321 */
322 @Override
323 public Type[] getGenericParameterTypes() {
324 return super.getGenericParameterTypes();
325 }
326
327 /**
328 * {@inheritDoc}
329 */
330 @Override
331 public Class<?>[] getExceptionTypes() {
332 return exceptionTypes.length == 0 ? exceptionTypes : exceptionTypes.clone();
333 }
334
335 /**
336 * {@inheritDoc}
337 * @throws GenericSignatureFormatError {@inheritDoc}
338 * @throws TypeNotPresentException {@inheritDoc}
339 * @throws MalformedParameterizedTypeException {@inheritDoc}
340 * @since 1.5
341 */
342 @Override
343 public Type[] getGenericExceptionTypes() {
344 return super.getGenericExceptionTypes();
345 }
346
347 /**
348 * Compares this {@code Method} against the specified object. Returns
349 * true if the objects are the same. Two {@code Methods} are the same if
350 * they were declared by the same class and have the same name
351 * and formal parameter types and return type.
352 */
353 public boolean equals(Object obj) {
354 if (obj instanceof Method other) {
355 if ((getDeclaringClass() == other.getDeclaringClass())
356 && (getName() == other.getName())) {
357 if (!returnType.equals(other.getReturnType()))
358 return false;
359 return equalParamTypes(parameterTypes, other.parameterTypes);
360 }
361 }
362 return false;
363 }
364
365 /**
366 * Returns a hashcode for this {@code Method}. The hashcode is computed
367 * as the exclusive-or of the hashcodes for the underlying
368 * method's declaring class name and the method's name.
369 */
370 public int hashCode() {
371 int hc = hash;
372
373 if (hc == 0) {
374 hc = hash = getDeclaringClass().getName().hashCode() ^ getName()
375 .hashCode();
376 }
377 return hc;
378 }
379
380 /**
381 * Returns a string describing this {@code Method}. The string is
382 * formatted as the method access modifiers, if any, followed by
383 * the method return type, followed by a space, followed by the
384 * class declaring the method, followed by a period, followed by
385 * the method name, followed by a parenthesized, comma-separated
386 * list of the method's formal parameter types. If the method
387 * throws checked exceptions, the parameter list is followed by a
388 * space, followed by the word "{@code throws}" followed by a
389 * comma-separated list of the thrown exception types.
390 * For example:
391 * <pre>
392 * public boolean java.lang.Object.equals(java.lang.Object)
393 * </pre>
394 *
395 * <p>The access modifiers are placed in canonical order as
396 * specified by "The Java Language Specification". This is
397 * {@code public}, {@code protected} or {@code private} first,
398 * and then other modifiers in the following order:
399 * {@code abstract}, {@code default}, {@code static}, {@code final},
400 * {@code synchronized}, {@code native}, {@code strictfp}.
401 *
402 * @return a string describing this {@code Method}
403 *
404 * @jls 8.4.3 Method Modifiers
405 * @jls 9.4 Method Declarations
406 * @jls 9.6.1 Annotation Interface Elements
407 */
408 public String toString() {
409 return sharedToString(Modifier.methodModifiers(),
410 isDefault(),
411 parameterTypes,
412 exceptionTypes);
413 }
414
415 @Override
416 void specificToStringHeader(StringBuilder sb) {
417 sb.append(getReturnType().getTypeName()).append(' ');
418 sb.append(getDeclaringClass().getTypeName()).append('.');
419 sb.append(getName());
420 }
421
422 @Override
423 String toShortString() {
424 return "method " + getDeclaringClass().getTypeName() +
425 '.' + toShortSignature();
426 }
427
428 String toShortSignature() {
429 StringJoiner sj = new StringJoiner(",", getName() + "(", ")");
430 for (Class<?> parameterType : getSharedParameterTypes()) {
431 sj.add(parameterType.getTypeName());
432 }
433 return sj.toString();
434 }
435
436 /**
437 * Returns a string describing this {@code Method}, including type
438 * parameters. The string is formatted as the method access
439 * modifiers, if any, followed by an angle-bracketed
440 * comma-separated list of the method's type parameters, if any,
441 * including informative bounds of the type parameters, if any,
442 * followed by the method's generic return type, followed by a
443 * space, followed by the class declaring the method, followed by
444 * a period, followed by the method name, followed by a
445 * parenthesized, comma-separated list of the method's generic
446 * formal parameter types.
447 *
448 * If this method was declared to take a variable number of
449 * arguments, instead of denoting the last parameter as
450 * "<code><i>Type</i>[]</code>", it is denoted as
451 * "<code><i>Type</i>...</code>".
452 *
453 * A space is used to separate access modifiers from one another
454 * and from the type parameters or return type. If there are no
455 * type parameters, the type parameter list is elided; if the type
456 * parameter list is present, a space separates the list from the
457 * class name. If the method is declared to throw exceptions, the
458 * parameter list is followed by a space, followed by the word
459 * "{@code throws}" followed by a comma-separated list of the generic
460 * thrown exception types.
461 *
462 * <p>The access modifiers are placed in canonical order as
463 * specified by "The Java Language Specification". This is
464 * {@code public}, {@code protected} or {@code private} first,
465 * and then other modifiers in the following order:
466 * {@code abstract}, {@code default}, {@code static}, {@code final},
467 * {@code synchronized}, {@code native}, {@code strictfp}.
468 *
469 * @return a string describing this {@code Method},
470 * include type parameters
471 *
472 * @since 1.5
473 *
474 * @jls 8.4.3 Method Modifiers
475 * @jls 9.4 Method Declarations
476 * @jls 9.6.1 Annotation Interface Elements
477 */
478 @Override
479 public String toGenericString() {
480 return sharedToGenericString(Modifier.methodModifiers(), isDefault());
481 }
482
483 @Override
484 void specificToGenericStringHeader(StringBuilder sb) {
485 Type genRetType = getGenericReturnType();
486 sb.append(genRetType.getTypeName()).append(' ');
487 sb.append(getDeclaringClass().getTypeName()).append('.');
488 sb.append(getName());
489 }
490
491 /**
492 * Invokes the underlying method represented by this {@code Method}
493 * object, on the specified object with the specified parameters.
494 * Individual parameters are automatically unwrapped to match
495 * primitive formal parameters, and both primitive and reference
496 * parameters are subject to method invocation conversions as
497 * necessary.
498 *
499 * <p>If the underlying method is static, then the specified {@code obj}
500 * argument is ignored. It may be null.
501 *
502 * <p>If the number of formal parameters required by the underlying method is
503 * 0, the supplied {@code args} array may be of length 0 or null.
504 *
505 * <p>If the underlying method is an instance method, it is invoked
506 * using dynamic method lookup as documented in The Java Language
507 * Specification, section {@jls 15.12.4.4}; in particular,
508 * overriding based on the runtime type of the target object may occur.
509 *
510 * <p>If the underlying method is static, the class that declared
511 * the method is initialized if it has not already been initialized.
512 *
513 * <p>If the method completes normally, the value it returns is
514 * returned to the caller of invoke; if the value has a primitive
515 * type, it is first appropriately wrapped in an object. However,
516 * if the value has the type of an array of a primitive type, the
517 * elements of the array are <i>not</i> wrapped in objects; in
518 * other words, an array of primitive type is returned. If the
519 * underlying method return type is void, the invocation returns
520 * null.
521 *
522 * @param obj the object the underlying method is invoked from
523 * @param args the arguments used for the method call
524 * @return the result of dispatching the method represented by
525 * this object on {@code obj} with parameters
526 * {@code args}
527 *
528 * @throws IllegalAccessException if this {@code Method} object
529 * is enforcing Java language access control and the underlying
530 * method is inaccessible.
531 * @throws IllegalArgumentException if the method is an
532 * instance method and the specified object argument
533 * is not an instance of the class or interface
534 * declaring the underlying method (or of a subclass
535 * or implementor thereof); if the number of actual
536 * and formal parameters differ; if an unwrapping
537 * conversion for primitive arguments fails; or if,
538 * after possible unwrapping, a parameter value
539 * cannot be converted to the corresponding formal
540 * parameter type by a method invocation conversion.
541 * @throws InvocationTargetException if the underlying method
542 * throws an exception.
543 * @throws NullPointerException if the specified object is null
544 * and the method is an instance method.
545 * @throws ExceptionInInitializerError if the initialization
546 * provoked by this method fails.
547 */
548 @CallerSensitive
549 @ForceInline // to ensure Reflection.getCallerClass optimization
550 @IntrinsicCandidate
551 public Object invoke(Object obj, Object... args)
552 throws IllegalAccessException, InvocationTargetException
553 {
554 boolean callerSensitive = isCallerSensitive();
555 Class<?> caller = null;
556 if (!override || callerSensitive) {
557 caller = Reflection.getCallerClass();
558 }
559
560 // Reflection::getCallerClass filters all subclasses of
561 // jdk.internal.reflect.MethodAccessorImpl and Method::invoke(Object, Object[])
562 // Should not call Method::invoke(Object, Object[], Class) here
563 if (!override) {
564 checkAccess(caller, clazz,
565 Modifier.isStatic(modifiers) ? null : obj.getClass(),
566 modifiers);
567 }
568 MethodAccessor ma = methodAccessor; // read @Stable
569 if (ma == null) {
570 ma = acquireMethodAccessor();
571 }
572
573 return callerSensitive ? ma.invoke(obj, args, caller) : ma.invoke(obj, args);
574 }
575
576 /**
577 * This is to support MethodHandle calling caller-sensitive Method::invoke
578 * that may invoke a caller-sensitive method in order to get the original caller
579 * class (not the injected invoker).
580 *
581 * If this adapter is not presented, MethodHandle invoking Method::invoke
582 * will get an invoker class, a hidden nestmate of the original caller class,
583 * that becomes the caller class invoking Method::invoke.
584 */
585 @CallerSensitiveAdapter
586 private Object invoke(Object obj, Object[] args, Class<?> caller)
587 throws IllegalAccessException, InvocationTargetException
588 {
589 boolean callerSensitive = isCallerSensitive();
590 if (!override) {
591 checkAccess(caller, clazz,
592 Modifier.isStatic(modifiers) ? null : obj.getClass(),
593 modifiers);
594 }
595 MethodAccessor ma = methodAccessor; // read @Stable
596 if (ma == null) {
597 ma = acquireMethodAccessor();
598 }
599
600 return callerSensitive ? ma.invoke(obj, args, caller) : ma.invoke(obj, args);
601 }
602
603 // 0 = not initialized (@Stable contract)
604 // 1 = initialized, CS
605 // -1 = initialized, not CS
606 @Stable private byte callerSensitive;
607
608 private boolean isCallerSensitive() {
609 byte cs = callerSensitive;
610 if (cs == 0) {
611 callerSensitive = cs = (byte)(Reflection.isCallerSensitive(this) ? 1 : -1);
612 }
613 return (cs > 0);
614 }
615
616 /**
617 * {@return {@code true} if this method is a bridge
618 * method; returns {@code false} otherwise}
619 *
620 * @apiNote
621 * A bridge method is a {@linkplain isSynthetic synthetic} method
622 * created by a Java compiler alongside a method originating from
623 * the source code. Bridge methods are used by Java compilers in
624 * various circumstances to span differences in Java programming
625 * language semantics and JVM semantics.
626 *
627 * <p>One example use of bridge methods is as a technique for a
628 * Java compiler to support <i>covariant overrides</i>, where a
629 * subclass overrides a method and gives the new method a more
630 * specific return type than the method in the superclass. While
631 * the Java language specification forbids a class declaring two
632 * methods with the same parameter types but a different return
633 * type, the virtual machine does not. A common case where
634 * covariant overrides are used is for a {@link
635 * java.lang.Cloneable Cloneable} class where the {@link
636 * Object#clone() clone} method inherited from {@code
637 * java.lang.Object} is overridden and declared to return the type
638 * of the class. For example, {@code Object} declares
639 * <pre>{@code protected Object clone() throws CloneNotSupportedException {...}}</pre>
640 * and {@code EnumSet<E>} declares its language-level {@linkplain
641 * java.util.EnumSet#clone() covariant override}
642 * <pre>{@code public EnumSet<E> clone() {...}}</pre>
643 * If this technique was being used, the resulting class file for
644 * {@code EnumSet} would have two {@code clone} methods, one
645 * returning {@code EnumSet<E>} and the second a bridge method
646 * returning {@code Object}. The bridge method is a JVM-level
647 * override of {@code Object.clone()}. The body of the {@code
648 * clone} bridge method calls its non-bridge counterpart and
649 * returns its result.
650 * @since 1.5
651 *
652 * @jls 8.4.8.3 Requirements in Overriding and Hiding
653 * @jls 15.12.4.5 Create Frame, Synchronize, Transfer Control
654 * @jvms 4.6 Methods
655 * @see <a
656 * href="{@docRoot}/java.base/java/lang/reflect/package-summary.html#LanguageJvmModel">Java
657 * programming language and JVM modeling in core reflection</a>
658 */
659 public boolean isBridge() {
660 return (getModifiers() & Modifier.BRIDGE) != 0;
661 }
662
663 /**
664 * {@inheritDoc}
665 * @since 1.5
666 * @jls 8.4.1 Formal Parameters
667 */
668 @Override
669 public boolean isVarArgs() {
670 return super.isVarArgs();
671 }
672
673 /**
674 * {@inheritDoc}
675 * @jls 13.1 The Form of a Binary
676 * @jvms 4.6 Methods
677 * @see <a
678 * href="{@docRoot}/java.base/java/lang/reflect/package-summary.html#LanguageJvmModel">Java
679 * programming language and JVM modeling in core reflection</a>
680 * @since 1.5
681 */
682 @Override
683 public boolean isSynthetic() {
684 return super.isSynthetic();
685 }
686
687 /**
688 * Returns {@code true} if this method is a default
689 * method; returns {@code false} otherwise.
690 *
691 * A default method is a public non-abstract instance method, that
692 * is, a non-static method with a body, declared in an interface.
693 *
694 * @return true if and only if this method is a default
695 * method as defined by the Java Language Specification.
696 * @since 1.8
697 * @jls 9.4 Method Declarations
698 */
699 public boolean isDefault() {
700 // Default methods are public non-abstract instance methods
701 // declared in an interface.
702 return ((getModifiers() & (Modifier.ABSTRACT | Modifier.PUBLIC | Modifier.STATIC)) ==
703 Modifier.PUBLIC) && getDeclaringClass().isInterface();
704 }
705
706 // NOTE that there is no synchronization used here. It is correct
707 // (though not efficient) to generate more than one MethodAccessor
708 // for a given Method. However, avoiding synchronization will
709 // probably make the implementation more scalable.
710 private MethodAccessor acquireMethodAccessor() {
711 // First check to see if one has been created yet, and take it
712 // if so
713 Method root = this.root;
714 MethodAccessor tmp = root == null ? null : root.getMethodAccessor();
715 if (tmp != null) {
716 methodAccessor = tmp;
717 } else {
718 // Otherwise fabricate one and propagate it up to the root
719 tmp = reflectionFactory.newMethodAccessor(this, isCallerSensitive());
720 // set the method accessor only if it's not using native implementation
721 if (VM.isJavaLangInvokeInited())
722 setMethodAccessor(tmp);
723 }
724
725 return tmp;
726 }
727
728 // Returns MethodAccessor for this Method object, not looking up
729 // the chain to the root
730 MethodAccessor getMethodAccessor() {
731 return methodAccessor;
732 }
733
734 // Sets the MethodAccessor for this Method object and
735 // (recursively) its root
736 void setMethodAccessor(MethodAccessor accessor) {
737 methodAccessor = accessor;
738 // Propagate up
739 Method root = this.root;
740 if (root != null) {
741 root.setMethodAccessor(accessor);
742 }
743 }
744
745 /**
746 * Returns the default value for the annotation member represented by
747 * this {@code Method} instance. If the member is of a primitive type,
748 * an instance of the corresponding wrapper type is returned. Returns
749 * null if no default is associated with the member, or if the method
750 * instance does not represent a declared member of an annotation type.
751 *
752 * @return the default value for the annotation member represented
753 * by this {@code Method} instance.
754 * @throws TypeNotPresentException if the annotation is of type
755 * {@link Class} and no definition can be found for the
756 * default class value.
757 * @since 1.5
758 * @jls 9.6.2 Defaults for Annotation Interface Elements
759 */
760 public Object getDefaultValue() {
761 if (annotationDefault == null)
762 return null;
763 Class<?> memberType = AnnotationType.invocationHandlerReturnType(
764 getReturnType());
765 Object result = AnnotationParser.parseMemberValue(
766 memberType, ByteBuffer.wrap(annotationDefault),
767 SharedSecrets.getJavaLangAccess().
768 getConstantPool(getDeclaringClass()),
769 getDeclaringClass());
770 if (result instanceof ExceptionProxy) {
771 if (result instanceof TypeNotPresentExceptionProxy proxy) {
772 throw new TypeNotPresentException(proxy.typeName(), proxy.getCause());
773 }
774 throw new AnnotationFormatError("Invalid default: " + this);
775 }
776 return result;
777 }
778
779 /**
780 * {@inheritDoc}
781 * @throws NullPointerException {@inheritDoc}
782 * @since 1.5
783 */
784 @Override
785 public <T extends Annotation> T getAnnotation(Class<T> annotationClass) {
786 return super.getAnnotation(annotationClass);
787 }
788
789 /**
790 * {@inheritDoc}
791 * @since 1.5
792 */
793 @Override
794 public Annotation[] getDeclaredAnnotations() {
795 return super.getDeclaredAnnotations();
796 }
797
798 /**
799 * {@inheritDoc}
800 * @since 1.5
801 */
802 @Override
803 public Annotation[][] getParameterAnnotations() {
804 return sharedGetParameterAnnotations(parameterTypes, parameterAnnotations);
805 }
806
807 /**
808 * {@inheritDoc}
809 * @since 1.8
810 */
811 @Override
812 public AnnotatedType getAnnotatedReturnType() {
813 return getAnnotatedReturnType0(getGenericReturnType());
814 }
815
816 @Override
817 boolean handleParameterNumberMismatch(int resultLength, Class<?>[] parameterTypes) {
818 throw new AnnotationFormatError("Parameter annotations don't match number of parameters");
819 }
820 }