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25 
26 package java.lang.reflect;
27 
28 import jdk.internal.access.SharedSecrets;
29 import jdk.internal.reflect.CallerSensitive;
30 import jdk.internal.reflect.MethodAccessor;
31 import jdk.internal.reflect.Reflection;
32 import jdk.internal.vm.annotation.ForceInline;
33 import jdk.internal.vm.annotation.IntrinsicCandidate;
34 import jdk.internal.vm.annotation.Stable;
35 import sun.reflect.annotation.ExceptionProxy;
36 import sun.reflect.annotation.TypeNotPresentExceptionProxy;
37 import sun.reflect.generics.repository.MethodRepository;
38 import sun.reflect.generics.factory.CoreReflectionFactory;
39 import sun.reflect.generics.factory.GenericsFactory;
40 import sun.reflect.generics.scope.MethodScope;
41 import sun.reflect.annotation.AnnotationType;
42 import sun.reflect.annotation.AnnotationParser;
43 import java.lang.annotation.Annotation;
44 import java.lang.annotation.AnnotationFormatError;
45 import java.nio.ByteBuffer;
46 import java.util.StringJoiner;
47 
48 /**
49  * A {@code Method} provides information about, and access to, a single method
50  * on a class or interface.  The reflected method may be a class method
51  * or an instance method (including an abstract method).
52  *
53  * <p>A {@code Method} permits widening conversions to occur when matching the
54  * actual parameters to invoke with the underlying method's formal
55  * parameters, but it throws an {@code IllegalArgumentException} if a
56  * narrowing conversion would occur.
57  *
58  * @see Member
59  * @see java.lang.Class
60  * @see java.lang.Class#getMethods()
61  * @see java.lang.Class#getMethod(String, Class[])
62  * @see java.lang.Class#getDeclaredMethods()
63  * @see java.lang.Class#getDeclaredMethod(String, Class[])
64  *
65  * @author Kenneth Russell
66  * @author Nakul Saraiya
67  * @since 1.1
68  */
69 public final class Method extends Executable {
70     @Stable
71     private Class<?>            clazz;
72     private int                 slot;
73     // This is guaranteed to be interned by the VM in the 1.4
74     // reflection implementation
75     private String              name;
76     private Class<?>            returnType;
77     private Class<?>[]          parameterTypes;
78     private Class<?>[]          exceptionTypes;
79     @Stable
80     private int                 modifiers;
81     // Generics and annotations support
82     private transient String              signature;
83     // generic info repository; lazily initialized
84     private transient MethodRepository genericInfo;
85     private byte[]              annotations;
86     private byte[]              parameterAnnotations;
87     private byte[]              annotationDefault;
88     private volatile MethodAccessor methodAccessor;
89     // For sharing of MethodAccessors. This branching structure is
90     // currently only two levels deep (i.e., one root Method and
91     // potentially many Method objects pointing to it.)
92     //
93     // If this branching structure would ever contain cycles, deadlocks can
94     // occur in annotation code.
95     private Method              root;
96 
97     // Generics infrastructure
getGenericSignature()98     private String getGenericSignature() {return signature;}
99 
100     // Accessor for factory
getFactory()101     private GenericsFactory getFactory() {
102         // create scope and factory
103         return CoreReflectionFactory.make(this, MethodScope.make(this));
104     }
105 
106     // Accessor for generic info repository
107     @Override
getGenericInfo()108     MethodRepository getGenericInfo() {
109         // lazily initialize repository if necessary
110         if (genericInfo == null) {
111             // create and cache generic info repository
112             genericInfo = MethodRepository.make(getGenericSignature(),
113                                                 getFactory());
114         }
115         return genericInfo; //return cached repository
116     }
117 
118     /**
119      * Package-private constructor
120      */
Method(Class<?> declaringClass, String name, Class<?>[] parameterTypes, Class<?> returnType, Class<?>[] checkedExceptions, int modifiers, int slot, String signature, byte[] annotations, byte[] parameterAnnotations, byte[] annotationDefault)121     Method(Class<?> declaringClass,
122            String name,
123            Class<?>[] parameterTypes,
124            Class<?> returnType,
125            Class<?>[] checkedExceptions,
126            int modifiers,
127            int slot,
128            String signature,
129            byte[] annotations,
130            byte[] parameterAnnotations,
131            byte[] annotationDefault) {
132         this.clazz = declaringClass;
133         this.name = name;
134         this.parameterTypes = parameterTypes;
135         this.returnType = returnType;
136         this.exceptionTypes = checkedExceptions;
137         this.modifiers = modifiers;
138         this.slot = slot;
139         this.signature = signature;
140         this.annotations = annotations;
141         this.parameterAnnotations = parameterAnnotations;
142         this.annotationDefault = annotationDefault;
143     }
144 
145     /**
146      * Package-private routine (exposed to java.lang.Class via
147      * ReflectAccess) which returns a copy of this Method. The copy's
148      * "root" field points to this Method.
149      */
copy()150     Method copy() {
151         // This routine enables sharing of MethodAccessor objects
152         // among Method objects which refer to the same underlying
153         // method in the VM. (All of this contortion is only necessary
154         // because of the "accessibility" bit in AccessibleObject,
155         // which implicitly requires that new java.lang.reflect
156         // objects be fabricated for each reflective call on Class
157         // objects.)
158         if (this.root != null)
159             throw new IllegalArgumentException("Can not copy a non-root Method");
160 
161         Method res = new Method(clazz, name, parameterTypes, returnType,
162                                 exceptionTypes, modifiers, slot, signature,
163                                 annotations, parameterAnnotations, annotationDefault);
164         res.root = this;
165         // Might as well eagerly propagate this if already present
166         res.methodAccessor = methodAccessor;
167         return res;
168     }
169 
170     /**
171      * Make a copy of a leaf method.
172      */
leafCopy()173     Method leafCopy() {
174         if (this.root == null)
175             throw new IllegalArgumentException("Can only leafCopy a non-root Method");
176 
177         Method res = new Method(clazz, name, parameterTypes, returnType,
178                 exceptionTypes, modifiers, slot, signature,
179                 annotations, parameterAnnotations, annotationDefault);
180         res.root = root;
181         res.methodAccessor = methodAccessor;
182         return res;
183     }
184 
185     /**
186      * @throws InaccessibleObjectException {@inheritDoc}
187      * @throws SecurityException {@inheritDoc}
188      */
189     @Override
190     @CallerSensitive
setAccessible(boolean flag)191     public void setAccessible(boolean flag) {
192         AccessibleObject.checkPermission();
193         if (flag) checkCanSetAccessible(Reflection.getCallerClass());
194         setAccessible0(flag);
195     }
196 
197     @Override
checkCanSetAccessible(Class<?> caller)198     void checkCanSetAccessible(Class<?> caller) {
199         checkCanSetAccessible(caller, clazz);
200     }
201 
202     @Override
getRoot()203     Method getRoot() {
204         return root;
205     }
206 
207     @Override
hasGenericInformation()208     boolean hasGenericInformation() {
209         return (getGenericSignature() != null);
210     }
211 
212     @Override
getAnnotationBytes()213     byte[] getAnnotationBytes() {
214         return annotations;
215     }
216 
217     /**
218      * Returns the {@code Class} object representing the class or interface
219      * that declares the method represented by this object.
220      */
221     @Override
getDeclaringClass()222     public Class<?> getDeclaringClass() {
223         return clazz;
224     }
225 
226     /**
227      * Returns the name of the method represented by this {@code Method}
228      * object, as a {@code String}.
229      */
230     @Override
getName()231     public String getName() {
232         return name;
233     }
234 
235     /**
236      * {@inheritDoc}
237      * @jls 8.4.3 Method Modifiers
238      */
239     @Override
getModifiers()240     public int getModifiers() {
241         return modifiers;
242     }
243 
244     /**
245      * {@inheritDoc}
246      * @throws GenericSignatureFormatError {@inheritDoc}
247      * @since 1.5
248      * @jls 8.4.4 Generic Methods
249      */
250     @Override
251     @SuppressWarnings({"rawtypes", "unchecked"})
getTypeParameters()252     public TypeVariable<Method>[] getTypeParameters() {
253         if (getGenericSignature() != null)
254             return (TypeVariable<Method>[])getGenericInfo().getTypeParameters();
255         else
256             return (TypeVariable<Method>[])new TypeVariable[0];
257     }
258 
259     /**
260      * Returns a {@code Class} object that represents the formal return type
261      * of the method represented by this {@code Method} object.
262      *
263      * @return the return type for the method this object represents
264      */
getReturnType()265     public Class<?> getReturnType() {
266         return returnType;
267     }
268 
269     /**
270      * Returns a {@code Type} object that represents the formal return
271      * type of the method represented by this {@code Method} object.
272      *
273      * <p>If the return type is a parameterized type,
274      * the {@code Type} object returned must accurately reflect
275      * the actual type arguments used in the source code.
276      *
277      * <p>If the return type is a type variable or a parameterized type, it
278      * is created. Otherwise, it is resolved.
279      *
280      * @return  a {@code Type} object that represents the formal return
281      *     type of the underlying  method
282      * @throws GenericSignatureFormatError
283      *     if the generic method signature does not conform to the format
284      *     specified in
285      *     <cite>The Java Virtual Machine Specification</cite>
286      * @throws TypeNotPresentException if the underlying method's
287      *     return type refers to a non-existent class or interface declaration
288      * @throws MalformedParameterizedTypeException if the
289      *     underlying method's return type refers to a parameterized
290      *     type that cannot be instantiated for any reason
291      * @since 1.5
292      */
getGenericReturnType()293     public Type getGenericReturnType() {
294       if (getGenericSignature() != null) {
295         return getGenericInfo().getReturnType();
296       } else { return getReturnType();}
297     }
298 
299     @Override
getSharedParameterTypes()300     Class<?>[] getSharedParameterTypes() {
301         return parameterTypes;
302     }
303 
304     @Override
getSharedExceptionTypes()305     Class<?>[] getSharedExceptionTypes() {
306         return exceptionTypes;
307     }
308 
309     /**
310      * {@inheritDoc}
311      */
312     @Override
getParameterTypes()313     public Class<?>[] getParameterTypes() {
314         return parameterTypes.clone();
315     }
316 
317     /**
318      * {@inheritDoc}
319      * @since 1.8
320      */
getParameterCount()321     public int getParameterCount() { return parameterTypes.length; }
322 
323 
324     /**
325      * {@inheritDoc}
326      * @throws GenericSignatureFormatError {@inheritDoc}
327      * @throws TypeNotPresentException {@inheritDoc}
328      * @throws MalformedParameterizedTypeException {@inheritDoc}
329      * @since 1.5
330      */
331     @Override
getGenericParameterTypes()332     public Type[] getGenericParameterTypes() {
333         return super.getGenericParameterTypes();
334     }
335 
336     /**
337      * {@inheritDoc}
338      */
339     @Override
getExceptionTypes()340     public Class<?>[] getExceptionTypes() {
341         return exceptionTypes.clone();
342     }
343 
344     /**
345      * {@inheritDoc}
346      * @throws GenericSignatureFormatError {@inheritDoc}
347      * @throws TypeNotPresentException {@inheritDoc}
348      * @throws MalformedParameterizedTypeException {@inheritDoc}
349      * @since 1.5
350      */
351     @Override
getGenericExceptionTypes()352     public Type[] getGenericExceptionTypes() {
353         return super.getGenericExceptionTypes();
354     }
355 
356     /**
357      * Compares this {@code Method} against the specified object.  Returns
358      * true if the objects are the same.  Two {@code Methods} are the same if
359      * they were declared by the same class and have the same name
360      * and formal parameter types and return type.
361      */
equals(Object obj)362     public boolean equals(Object obj) {
363         if (obj instanceof Method other) {
364             if ((getDeclaringClass() == other.getDeclaringClass())
365                 && (getName() == other.getName())) {
366                 if (!returnType.equals(other.getReturnType()))
367                     return false;
368                 return equalParamTypes(parameterTypes, other.parameterTypes);
369             }
370         }
371         return false;
372     }
373 
374     /**
375      * Returns a hashcode for this {@code Method}.  The hashcode is computed
376      * as the exclusive-or of the hashcodes for the underlying
377      * method's declaring class name and the method's name.
378      */
hashCode()379     public int hashCode() {
380         return getDeclaringClass().getName().hashCode() ^ getName().hashCode();
381     }
382 
383     /**
384      * Returns a string describing this {@code Method}.  The string is
385      * formatted as the method access modifiers, if any, followed by
386      * the method return type, followed by a space, followed by the
387      * class declaring the method, followed by a period, followed by
388      * the method name, followed by a parenthesized, comma-separated
389      * list of the method's formal parameter types. If the method
390      * throws checked exceptions, the parameter list is followed by a
391      * space, followed by the word "{@code throws}" followed by a
392      * comma-separated list of the thrown exception types.
393      * For example:
394      * <pre>
395      *    public boolean java.lang.Object.equals(java.lang.Object)
396      * </pre>
397      *
398      * <p>The access modifiers are placed in canonical order as
399      * specified by "The Java Language Specification".  This is
400      * {@code public}, {@code protected} or {@code private} first,
401      * and then other modifiers in the following order:
402      * {@code abstract}, {@code default}, {@code static}, {@code final},
403      * {@code synchronized}, {@code native}, {@code strictfp}.
404      *
405      * @return a string describing this {@code Method}
406      *
407      * @jls 8.4.3 Method Modifiers
408      * @jls 9.4 Method Declarations
409      * @jls 9.6.1 Annotation Interface Elements
410      */
toString()411     public String toString() {
412         return sharedToString(Modifier.methodModifiers(),
413                               isDefault(),
414                               parameterTypes,
415                               exceptionTypes);
416     }
417 
418     @Override
specificToStringHeader(StringBuilder sb)419     void specificToStringHeader(StringBuilder sb) {
420         sb.append(getReturnType().getTypeName()).append(' ');
421         sb.append(getDeclaringClass().getTypeName()).append('.');
422         sb.append(getName());
423     }
424 
425     @Override
toShortString()426     String toShortString() {
427         return "method " + getDeclaringClass().getTypeName() +
428                 '.' + toShortSignature();
429     }
430 
toShortSignature()431     String toShortSignature() {
432         StringJoiner sj = new StringJoiner(",", getName() + "(", ")");
433         for (Class<?> parameterType : getParameterTypes()) {
434             sj.add(parameterType.getTypeName());
435         }
436         return sj.toString();
437     }
438 
439     /**
440      * Returns a string describing this {@code Method}, including type
441      * parameters.  The string is formatted as the method access
442      * modifiers, if any, followed by an angle-bracketed
443      * comma-separated list of the method's type parameters, if any,
444      * including informative bounds of the type parameters, if any,
445      * followed by the method's generic return type, followed by a
446      * space, followed by the class declaring the method, followed by
447      * a period, followed by the method name, followed by a
448      * parenthesized, comma-separated list of the method's generic
449      * formal parameter types.
450      *
451      * If this method was declared to take a variable number of
452      * arguments, instead of denoting the last parameter as
453      * "<code><i>Type</i>[]</code>", it is denoted as
454      * "<code><i>Type</i>...</code>".
455      *
456      * A space is used to separate access modifiers from one another
457      * and from the type parameters or return type.  If there are no
458      * type parameters, the type parameter list is elided; if the type
459      * parameter list is present, a space separates the list from the
460      * class name.  If the method is declared to throw exceptions, the
461      * parameter list is followed by a space, followed by the word
462      * "{@code throws}" followed by a comma-separated list of the generic
463      * thrown exception types.
464      *
465      * <p>The access modifiers are placed in canonical order as
466      * specified by "The Java Language Specification".  This is
467      * {@code public}, {@code protected} or {@code private} first,
468      * and then other modifiers in the following order:
469      * {@code abstract}, {@code default}, {@code static}, {@code final},
470      * {@code synchronized}, {@code native}, {@code strictfp}.
471      *
472      * @return a string describing this {@code Method},
473      * include type parameters
474      *
475      * @since 1.5
476      *
477      * @jls 8.4.3 Method Modifiers
478      * @jls 9.4 Method Declarations
479      * @jls 9.6.1 Annotation Interface Elements
480      */
481     @Override
toGenericString()482     public String toGenericString() {
483         return sharedToGenericString(Modifier.methodModifiers(), isDefault());
484     }
485 
486     @Override
specificToGenericStringHeader(StringBuilder sb)487     void specificToGenericStringHeader(StringBuilder sb) {
488         Type genRetType = getGenericReturnType();
489         sb.append(genRetType.getTypeName()).append(' ');
490         sb.append(getDeclaringClass().getTypeName()).append('.');
491         sb.append(getName());
492     }
493 
494     /**
495      * Invokes the underlying method represented by this {@code Method}
496      * object, on the specified object with the specified parameters.
497      * Individual parameters are automatically unwrapped to match
498      * primitive formal parameters, and both primitive and reference
499      * parameters are subject to method invocation conversions as
500      * necessary.
501      *
502      * <p>If the underlying method is static, then the specified {@code obj}
503      * argument is ignored. It may be null.
504      *
505      * <p>If the number of formal parameters required by the underlying method is
506      * 0, the supplied {@code args} array may be of length 0 or null.
507      *
508      * <p>If the underlying method is an instance method, it is invoked
509      * using dynamic method lookup as documented in The Java Language
510      * Specification, section {@jls 15.12.4.4}; in particular,
511      * overriding based on the runtime type of the target object may occur.
512      *
513      * <p>If the underlying method is static, the class that declared
514      * the method is initialized if it has not already been initialized.
515      *
516      * <p>If the method completes normally, the value it returns is
517      * returned to the caller of invoke; if the value has a primitive
518      * type, it is first appropriately wrapped in an object. However,
519      * if the value has the type of an array of a primitive type, the
520      * elements of the array are <i>not</i> wrapped in objects; in
521      * other words, an array of primitive type is returned.  If the
522      * underlying method return type is void, the invocation returns
523      * null.
524      *
525      * @param obj  the object the underlying method is invoked from
526      * @param args the arguments used for the method call
527      * @return the result of dispatching the method represented by
528      * this object on {@code obj} with parameters
529      * {@code args}
530      *
531      * @throws    IllegalAccessException    if this {@code Method} object
532      *              is enforcing Java language access control and the underlying
533      *              method is inaccessible.
534      * @throws    IllegalArgumentException  if the method is an
535      *              instance method and the specified object argument
536      *              is not an instance of the class or interface
537      *              declaring the underlying method (or of a subclass
538      *              or implementor thereof); if the number of actual
539      *              and formal parameters differ; if an unwrapping
540      *              conversion for primitive arguments fails; or if,
541      *              after possible unwrapping, a parameter value
542      *              cannot be converted to the corresponding formal
543      *              parameter type by a method invocation conversion.
544      * @throws    InvocationTargetException if the underlying method
545      *              throws an exception.
546      * @throws    NullPointerException      if the specified object is null
547      *              and the method is an instance method.
548      * @throws    ExceptionInInitializerError if the initialization
549      * provoked by this method fails.
550      */
551     @CallerSensitive
552     @ForceInline // to ensure Reflection.getCallerClass optimization
553     @IntrinsicCandidate
invoke(Object obj, Object... args)554     public Object invoke(Object obj, Object... args)
555         throws IllegalAccessException, IllegalArgumentException,
556            InvocationTargetException
557     {
558         if (!override) {
559             Class<?> caller = Reflection.getCallerClass();
560             checkAccess(caller, clazz,
561                         Modifier.isStatic(modifiers) ? null : obj.getClass(),
562                         modifiers);
563         }
564         MethodAccessor ma = methodAccessor;             // read volatile
565         if (ma == null) {
566             ma = acquireMethodAccessor();
567         }
568         return ma.invoke(obj, args);
569     }
570 
571     /**
572      * {@return {@code true} if this method is a bridge
573      * method; returns {@code false} otherwise}
574      *
575      * @apiNote
576      * A bridge method is a {@linkplain isSynthetic synthetic} method
577      * created by a Java compiler alongside a method originating from
578      * the source code. Bridge methods are used by Java compilers in
579      * various circumstances to span differences in Java programming
580      * language semantics and JVM semantics.
581      *
582      * <p>One example use of bridge methods is as a technique for a
583      * Java compiler to support <i>covariant overrides</i>, where a
584      * subclass overrides a method and gives the new method a more
585      * specific return type than the method in the superclass.  While
586      * the Java language specification forbids a class declaring two
587      * methods with the same parameter types but a different return
588      * type, the virtual machine does not. A common case where
589      * covariant overrides are used is for a {@link
590      * java.lang.Cloneable Cloneable} class where the {@link
591      * Object#clone() clone} method inherited from {@code
592      * java.lang.Object} is overridden and declared to return the type
593      * of the class. For example, {@code Object} declares
594      * <pre>{@code protected Object clone() throws CloneNotSupportedException {...}}</pre>
595      * and {@code EnumSet<E>} declares its language-level {@linkplain
596      * java.util.EnumSet#clone() covariant override}
597      * <pre>{@code public EnumSet<E> clone() {...}}</pre>
598      * If this technique was being used, the resulting class file for
599      * {@code EnumSet} would have two {@code clone} methods, one
600      * returning {@code EnumSet<E>} and the second a bridge method
601      * returning {@code Object}. The bridge method is a JVM-level
602      * override of {@code Object.clone()}.  The body of the {@code
603      * clone} bridge method calls its non-bridge counterpart and
604      * returns its result.
605      * @since 1.5
606      *
607      * @jls 8.4.8.3 Requirements in Overriding and Hiding
608      * @jls 15.12.4.5 Create Frame, Synchronize, Transfer Control
609      * @jvms 4.6 Methods
610      * @see <a
611      * href="{@docRoot}/java.base/java/lang/reflect/package-summary.html#LanguageJvmModel">Java
612      * programming language and JVM modeling in core reflection</a>
613      */
isBridge()614     public boolean isBridge() {
615         return (getModifiers() & Modifier.BRIDGE) != 0;
616     }
617 
618     /**
619      * {@inheritDoc}
620      * @since 1.5
621      * @jls 8.4.1 Formal Parameters
622      */
623     @Override
isVarArgs()624     public boolean isVarArgs() {
625         return super.isVarArgs();
626     }
627 
628     /**
629      * {@inheritDoc}
630      * @jls 13.1 The Form of a Binary
631      * @jvms 4.6 Methods
632      * @see <a
633      * href="{@docRoot}/java.base/java/lang/reflect/package-summary.html#LanguageJvmModel">Java
634      * programming language and JVM modeling in core reflection</a>
635      * @since 1.5
636      */
637     @Override
isSynthetic()638     public boolean isSynthetic() {
639         return super.isSynthetic();
640     }
641 
642     /**
643      * Returns {@code true} if this method is a default
644      * method; returns {@code false} otherwise.
645      *
646      * A default method is a public non-abstract instance method, that
647      * is, a non-static method with a body, declared in an interface.
648      *
649      * @return true if and only if this method is a default
650      * method as defined by the Java Language Specification.
651      * @since 1.8
652      * @jls 9.4 Method Declarations
653      */
isDefault()654     public boolean isDefault() {
655         // Default methods are public non-abstract instance methods
656         // declared in an interface.
657         return ((getModifiers() & (Modifier.ABSTRACT | Modifier.PUBLIC | Modifier.STATIC)) ==
658                 Modifier.PUBLIC) && getDeclaringClass().isInterface();
659     }
660 
661     // NOTE that there is no synchronization used here. It is correct
662     // (though not efficient) to generate more than one MethodAccessor
663     // for a given Method. However, avoiding synchronization will
664     // probably make the implementation more scalable.
acquireMethodAccessor()665     private MethodAccessor acquireMethodAccessor() {
666         // First check to see if one has been created yet, and take it
667         // if so
668         MethodAccessor tmp = null;
669         if (root != null) tmp = root.getMethodAccessor();
670         if (tmp != null) {
671             methodAccessor = tmp;
672         } else {
673             // Otherwise fabricate one and propagate it up to the root
674             tmp = reflectionFactory.newMethodAccessor(this);
675             setMethodAccessor(tmp);
676         }
677 
678         return tmp;
679     }
680 
681     // Returns MethodAccessor for this Method object, not looking up
682     // the chain to the root
getMethodAccessor()683     MethodAccessor getMethodAccessor() {
684         return methodAccessor;
685     }
686 
687     // Sets the MethodAccessor for this Method object and
688     // (recursively) its root
setMethodAccessor(MethodAccessor accessor)689     void setMethodAccessor(MethodAccessor accessor) {
690         methodAccessor = accessor;
691         // Propagate up
692         if (root != null) {
693             root.setMethodAccessor(accessor);
694         }
695     }
696 
697     /**
698      * Returns the default value for the annotation member represented by
699      * this {@code Method} instance.  If the member is of a primitive type,
700      * an instance of the corresponding wrapper type is returned. Returns
701      * null if no default is associated with the member, or if the method
702      * instance does not represent a declared member of an annotation type.
703      *
704      * @return the default value for the annotation member represented
705      *     by this {@code Method} instance.
706      * @throws TypeNotPresentException if the annotation is of type
707      *     {@link Class} and no definition can be found for the
708      *     default class value.
709      * @since  1.5
710      * @jls 9.6.2 Defaults for Annotation Type Elements
711      */
getDefaultValue()712     public Object getDefaultValue() {
713         if  (annotationDefault == null)
714             return null;
715         Class<?> memberType = AnnotationType.invocationHandlerReturnType(
716             getReturnType());
717         Object result = AnnotationParser.parseMemberValue(
718             memberType, ByteBuffer.wrap(annotationDefault),
719             SharedSecrets.getJavaLangAccess().
720                 getConstantPool(getDeclaringClass()),
721             getDeclaringClass());
722         if (result instanceof ExceptionProxy) {
723             if (result instanceof TypeNotPresentExceptionProxy proxy) {
724                 throw new TypeNotPresentException(proxy.typeName(), proxy.getCause());
725             }
726             throw new AnnotationFormatError("Invalid default: " + this);
727         }
728         return result;
729     }
730 
731     /**
732      * {@inheritDoc}
733      * @throws NullPointerException {@inheritDoc}
734      * @since 1.5
735      */
736     @Override
getAnnotation(Class<T> annotationClass)737     public <T extends Annotation> T getAnnotation(Class<T> annotationClass) {
738         return super.getAnnotation(annotationClass);
739     }
740 
741     /**
742      * {@inheritDoc}
743      * @since 1.5
744      */
745     @Override
getDeclaredAnnotations()746     public Annotation[] getDeclaredAnnotations()  {
747         return super.getDeclaredAnnotations();
748     }
749 
750     /**
751      * {@inheritDoc}
752      * @since 1.5
753      */
754     @Override
getParameterAnnotations()755     public Annotation[][] getParameterAnnotations() {
756         return sharedGetParameterAnnotations(parameterTypes, parameterAnnotations);
757     }
758 
759     /**
760      * {@inheritDoc}
761      * @since 1.8
762      */
763     @Override
getAnnotatedReturnType()764     public AnnotatedType getAnnotatedReturnType() {
765         return getAnnotatedReturnType0(getGenericReturnType());
766     }
767 
768     @Override
handleParameterNumberMismatch(int resultLength, Class<?>[] parameterTypes)769     boolean handleParameterNumberMismatch(int resultLength, Class<?>[] parameterTypes) {
770         throw new AnnotationFormatError("Parameter annotations don't match number of parameters");
771     }
772 }
773