44 * or an instance method (including an abstract method).
45 *
46 * <p>A {@code Method} permits widening conversions to occur when matching the
47 * actual parameters to invoke with the underlying method's formal
48 * parameters, but it throws an {@code IllegalArgumentException} if a
49 * narrowing conversion would occur.
50 *
51 * @see Member
52 * @see java.lang.Class
53 * @see java.lang.Class#getMethods()
54 * @see java.lang.Class#getMethod(String, Class[])
55 * @see java.lang.Class#getDeclaredMethods()
56 * @see java.lang.Class#getDeclaredMethod(String, Class[])
57 *
58 * @author Kenneth Russell
59 * @author Nakul Saraiya
60 */
61 public final
62 class Method extends AccessibleObject implements GenericDeclaration,
63 Member {
64 private Class clazz;
65 private int slot;
66 // This is guaranteed to be interned by the VM in the 1.4
67 // reflection implementation
68 private String name;
69 private Class returnType;
70 private Class[] parameterTypes;
71 private Class[] exceptionTypes;
72 private int modifiers;
73 // Generics and annotations support
74 private transient String signature;
75 // generic info repository; lazily initialized
76 private transient MethodRepository genericInfo;
77 private byte[] annotations;
78 private byte[] parameterAnnotations;
79 private byte[] annotationDefault;
80 private volatile MethodAccessor methodAccessor;
81 // For sharing of MethodAccessors. This branching structure is
82 // currently only two levels deep (i.e., one root Method and
83 // potentially many Method objects pointing to it.)
84 private Method root;
85
86 // More complicated security check cache needed here than for
87 // Class.newInstance() and Constructor.newInstance()
88 private Class securityCheckCache;
89 private Class securityCheckTargetClassCache;
90
91 // Generics infrastructure
92
93 private String getGenericSignature() {return signature;}
94
95 // Accessor for factory
96 private GenericsFactory getFactory() {
97 // create scope and factory
98 return CoreReflectionFactory.make(this, MethodScope.make(this));
99 }
100
101 // Accessor for generic info repository
102 private MethodRepository getGenericInfo() {
103 // lazily initialize repository if necessary
104 if (genericInfo == null) {
105 // create and cache generic info repository
106 genericInfo = MethodRepository.make(getGenericSignature(),
107 getFactory());
108 }
109 return genericInfo; //return cached repository
110 }
111
112 /**
113 * Package-private constructor used by ReflectAccess to enable
114 * instantiation of these objects in Java code from the java.lang
115 * package via sun.reflect.LangReflectAccess.
116 */
117 Method(Class declaringClass,
118 String name,
119 Class[] parameterTypes,
120 Class returnType,
121 Class[] checkedExceptions,
122 int modifiers,
123 int slot,
124 String signature,
125 byte[] annotations,
126 byte[] parameterAnnotations,
127 byte[] annotationDefault)
128 {
129 this.clazz = declaringClass;
130 this.name = name;
131 this.parameterTypes = parameterTypes;
132 this.returnType = returnType;
133 this.exceptionTypes = checkedExceptions;
134 this.modifiers = modifiers;
135 this.slot = slot;
136 this.signature = signature;
137 this.annotations = annotations;
138 this.parameterAnnotations = parameterAnnotations;
139 this.annotationDefault = annotationDefault;
140 }
141
338 ((result = getGenericInfo().getExceptionTypes()).length > 0))
339 return result;
340 else
341 return getExceptionTypes();
342 }
343
344 /**
345 * Compares this {@code Method} against the specified object. Returns
346 * true if the objects are the same. Two {@code Methods} are the same if
347 * they were declared by the same class and have the same name
348 * and formal parameter types and return type.
349 */
350 public boolean equals(Object obj) {
351 if (obj != null && obj instanceof Method) {
352 Method other = (Method)obj;
353 if ((getDeclaringClass() == other.getDeclaringClass())
354 && (getName() == other.getName())) {
355 if (!returnType.equals(other.getReturnType()))
356 return false;
357 /* Avoid unnecessary cloning */
358 Class[] params1 = parameterTypes;
359 Class[] params2 = other.parameterTypes;
360 if (params1.length == params2.length) {
361 for (int i = 0; i < params1.length; i++) {
362 if (params1[i] != params2[i])
363 return false;
364 }
365 return true;
366 }
367 }
368 }
369 return false;
370 }
371
372 /**
373 * Returns a hashcode for this {@code Method}. The hashcode is computed
374 * as the exclusive-or of the hashcodes for the underlying
375 * method's declaring class name and the method's name.
376 */
377 public int hashCode() {
378 return getDeclaringClass().getName().hashCode() ^ getName().hashCode();
379 }
393 * public boolean java.lang.Object.equals(java.lang.Object)
394 * </pre>
395 *
396 * <p>The access modifiers are placed in canonical order as
397 * specified by "The Java Language Specification". This is
398 * {@code public}, {@code protected} or {@code private} first,
399 * and then other modifiers in the following order:
400 * {@code abstract}, {@code static}, {@code final},
401 * {@code synchronized}, {@code native}, {@code strictfp}.
402 */
403 public String toString() {
404 try {
405 StringBuffer sb = new StringBuffer();
406 int mod = getModifiers() & Modifier.methodModifiers();
407 if (mod != 0) {
408 sb.append(Modifier.toString(mod) + " ");
409 }
410 sb.append(Field.getTypeName(getReturnType()) + " ");
411 sb.append(Field.getTypeName(getDeclaringClass()) + ".");
412 sb.append(getName() + "(");
413 Class[] params = parameterTypes; // avoid clone
414 for (int j = 0; j < params.length; j++) {
415 sb.append(Field.getTypeName(params[j]));
416 if (j < (params.length - 1))
417 sb.append(",");
418 }
419 sb.append(")");
420 Class[] exceptions = exceptionTypes; // avoid clone
421 if (exceptions.length > 0) {
422 sb.append(" throws ");
423 for (int k = 0; k < exceptions.length; k++) {
424 sb.append(exceptions[k].getName());
425 if (k < (exceptions.length - 1))
426 sb.append(",");
427 }
428 }
429 return sb.toString();
430 } catch (Exception e) {
431 return "<" + e + ">";
432 }
433 }
434
435 /**
436 * Returns a string describing this {@code Method}, including
437 * type parameters. The string is formatted as the method access
438 * modifiers, if any, followed by an angle-bracketed
439 * comma-separated list of the method's type parameters, if any,
440 * followed by the method's generic return type, followed by a
573 * declaring the underlying method (or of a subclass
574 * or implementor thereof); if the number of actual
575 * and formal parameters differ; if an unwrapping
576 * conversion for primitive arguments fails; or if,
577 * after possible unwrapping, a parameter value
578 * cannot be converted to the corresponding formal
579 * parameter type by a method invocation conversion.
580 * @exception InvocationTargetException if the underlying method
581 * throws an exception.
582 * @exception NullPointerException if the specified object is null
583 * and the method is an instance method.
584 * @exception ExceptionInInitializerError if the initialization
585 * provoked by this method fails.
586 */
587 public Object invoke(Object obj, Object... args)
588 throws IllegalAccessException, IllegalArgumentException,
589 InvocationTargetException
590 {
591 if (!override) {
592 if (!Reflection.quickCheckMemberAccess(clazz, modifiers)) {
593 Class caller = Reflection.getCallerClass(1);
594 Class targetClass = ((obj == null || !Modifier.isProtected(modifiers))
595 ? clazz
596 : obj.getClass());
597
598 boolean cached;
599 synchronized (this) {
600 cached = (securityCheckCache == caller)
601 && (securityCheckTargetClassCache == targetClass);
602 }
603 if (!cached) {
604 Reflection.ensureMemberAccess(caller, clazz, obj, modifiers);
605 synchronized (this) {
606 securityCheckCache = caller;
607 securityCheckTargetClassCache = targetClass;
608 }
609 }
610 }
611 }
612 if (methodAccessor == null) acquireMethodAccessor();
613 return methodAccessor.invoke(obj, args);
614 }
685 }
686
687 /**
688 * @throws NullPointerException {@inheritDoc}
689 * @since 1.5
690 */
691 public <T extends Annotation> T getAnnotation(Class<T> annotationClass) {
692 if (annotationClass == null)
693 throw new NullPointerException();
694
695 return (T) declaredAnnotations().get(annotationClass);
696 }
697
698 /**
699 * @since 1.5
700 */
701 public Annotation[] getDeclaredAnnotations() {
702 return AnnotationParser.toArray(declaredAnnotations());
703 }
704
705 private transient Map<Class, Annotation> declaredAnnotations;
706
707 private synchronized Map<Class, Annotation> declaredAnnotations() {
708 if (declaredAnnotations == null) {
709 declaredAnnotations = AnnotationParser.parseAnnotations(
710 annotations, sun.misc.SharedSecrets.getJavaLangAccess().
711 getConstantPool(getDeclaringClass()),
712 getDeclaringClass());
713 }
714 return declaredAnnotations;
715 }
716
717 /**
718 * Returns the default value for the annotation member represented by
719 * this {@code Method} instance. If the member is of a primitive type,
720 * an instance of the corresponding wrapper type is returned. Returns
721 * null if no default is associated with the member, or if the method
722 * instance does not represent a declared member of an annotation type.
723 *
724 * @return the default value for the annotation member represented
725 * by this {@code Method} instance.
726 * @throws TypeNotPresentException if the annotation is of type
727 * {@link Class} and no definition can be found for the
728 * default class value.
729 * @since 1.5
730 */
731 public Object getDefaultValue() {
732 if (annotationDefault == null)
733 return null;
734 Class memberType = AnnotationType.invocationHandlerReturnType(
735 getReturnType());
736 Object result = AnnotationParser.parseMemberValue(
737 memberType, ByteBuffer.wrap(annotationDefault),
738 sun.misc.SharedSecrets.getJavaLangAccess().
739 getConstantPool(getDeclaringClass()),
740 getDeclaringClass());
741 if (result instanceof sun.reflect.annotation.ExceptionProxy)
742 throw new AnnotationFormatError("Invalid default: " + this);
743 return result;
744 }
745
746 /**
747 * Returns an array of arrays that represent the annotations on the formal
748 * parameters, in declaration order, of the method represented by
749 * this {@code Method} object. (Returns an array of length zero if the
750 * underlying method is parameterless. If the method has one or more
751 * parameters, a nested array of length zero is returned for each parameter
752 * with no annotations.) The annotation objects contained in the returned
753 * arrays are serializable. The caller of this method is free to modify
754 * the returned arrays; it will have no effect on the arrays returned to
|
44 * or an instance method (including an abstract method).
45 *
46 * <p>A {@code Method} permits widening conversions to occur when matching the
47 * actual parameters to invoke with the underlying method's formal
48 * parameters, but it throws an {@code IllegalArgumentException} if a
49 * narrowing conversion would occur.
50 *
51 * @see Member
52 * @see java.lang.Class
53 * @see java.lang.Class#getMethods()
54 * @see java.lang.Class#getMethod(String, Class[])
55 * @see java.lang.Class#getDeclaredMethods()
56 * @see java.lang.Class#getDeclaredMethod(String, Class[])
57 *
58 * @author Kenneth Russell
59 * @author Nakul Saraiya
60 */
61 public final
62 class Method extends AccessibleObject implements GenericDeclaration,
63 Member {
64 private Class<?> clazz;
65 private int slot;
66 // This is guaranteed to be interned by the VM in the 1.4
67 // reflection implementation
68 private String name;
69 private Class<?> returnType;
70 private Class<?>[] parameterTypes;
71 private Class<?>[] exceptionTypes;
72 private int modifiers;
73 // Generics and annotations support
74 private transient String signature;
75 // generic info repository; lazily initialized
76 private transient MethodRepository genericInfo;
77 private byte[] annotations;
78 private byte[] parameterAnnotations;
79 private byte[] annotationDefault;
80 private volatile MethodAccessor methodAccessor;
81 // For sharing of MethodAccessors. This branching structure is
82 // currently only two levels deep (i.e., one root Method and
83 // potentially many Method objects pointing to it.)
84 private Method root;
85
86 // More complicated security check cache needed here than for
87 // Class.newInstance() and Constructor.newInstance()
88 private Class<?> securityCheckCache;
89 private Class<?> securityCheckTargetClassCache;
90
91 // Generics infrastructure
92
93 private String getGenericSignature() {return signature;}
94
95 // Accessor for factory
96 private GenericsFactory getFactory() {
97 // create scope and factory
98 return CoreReflectionFactory.make(this, MethodScope.make(this));
99 }
100
101 // Accessor for generic info repository
102 private MethodRepository getGenericInfo() {
103 // lazily initialize repository if necessary
104 if (genericInfo == null) {
105 // create and cache generic info repository
106 genericInfo = MethodRepository.make(getGenericSignature(),
107 getFactory());
108 }
109 return genericInfo; //return cached repository
110 }
111
112 /**
113 * Package-private constructor used by ReflectAccess to enable
114 * instantiation of these objects in Java code from the java.lang
115 * package via sun.reflect.LangReflectAccess.
116 */
117 Method(Class<?> declaringClass,
118 String name,
119 Class<?>[] parameterTypes,
120 Class<?> returnType,
121 Class<?>[] checkedExceptions,
122 int modifiers,
123 int slot,
124 String signature,
125 byte[] annotations,
126 byte[] parameterAnnotations,
127 byte[] annotationDefault)
128 {
129 this.clazz = declaringClass;
130 this.name = name;
131 this.parameterTypes = parameterTypes;
132 this.returnType = returnType;
133 this.exceptionTypes = checkedExceptions;
134 this.modifiers = modifiers;
135 this.slot = slot;
136 this.signature = signature;
137 this.annotations = annotations;
138 this.parameterAnnotations = parameterAnnotations;
139 this.annotationDefault = annotationDefault;
140 }
141
338 ((result = getGenericInfo().getExceptionTypes()).length > 0))
339 return result;
340 else
341 return getExceptionTypes();
342 }
343
344 /**
345 * Compares this {@code Method} against the specified object. Returns
346 * true if the objects are the same. Two {@code Methods} are the same if
347 * they were declared by the same class and have the same name
348 * and formal parameter types and return type.
349 */
350 public boolean equals(Object obj) {
351 if (obj != null && obj instanceof Method) {
352 Method other = (Method)obj;
353 if ((getDeclaringClass() == other.getDeclaringClass())
354 && (getName() == other.getName())) {
355 if (!returnType.equals(other.getReturnType()))
356 return false;
357 /* Avoid unnecessary cloning */
358 Class<?>[] params1 = parameterTypes;
359 Class<?>[] params2 = other.parameterTypes;
360 if (params1.length == params2.length) {
361 for (int i = 0; i < params1.length; i++) {
362 if (params1[i] != params2[i])
363 return false;
364 }
365 return true;
366 }
367 }
368 }
369 return false;
370 }
371
372 /**
373 * Returns a hashcode for this {@code Method}. The hashcode is computed
374 * as the exclusive-or of the hashcodes for the underlying
375 * method's declaring class name and the method's name.
376 */
377 public int hashCode() {
378 return getDeclaringClass().getName().hashCode() ^ getName().hashCode();
379 }
393 * public boolean java.lang.Object.equals(java.lang.Object)
394 * </pre>
395 *
396 * <p>The access modifiers are placed in canonical order as
397 * specified by "The Java Language Specification". This is
398 * {@code public}, {@code protected} or {@code private} first,
399 * and then other modifiers in the following order:
400 * {@code abstract}, {@code static}, {@code final},
401 * {@code synchronized}, {@code native}, {@code strictfp}.
402 */
403 public String toString() {
404 try {
405 StringBuffer sb = new StringBuffer();
406 int mod = getModifiers() & Modifier.methodModifiers();
407 if (mod != 0) {
408 sb.append(Modifier.toString(mod) + " ");
409 }
410 sb.append(Field.getTypeName(getReturnType()) + " ");
411 sb.append(Field.getTypeName(getDeclaringClass()) + ".");
412 sb.append(getName() + "(");
413 Class<?>[] params = parameterTypes; // avoid clone
414 for (int j = 0; j < params.length; j++) {
415 sb.append(Field.getTypeName(params[j]));
416 if (j < (params.length - 1))
417 sb.append(",");
418 }
419 sb.append(")");
420 Class<?>[] exceptions = exceptionTypes; // avoid clone
421 if (exceptions.length > 0) {
422 sb.append(" throws ");
423 for (int k = 0; k < exceptions.length; k++) {
424 sb.append(exceptions[k].getName());
425 if (k < (exceptions.length - 1))
426 sb.append(",");
427 }
428 }
429 return sb.toString();
430 } catch (Exception e) {
431 return "<" + e + ">";
432 }
433 }
434
435 /**
436 * Returns a string describing this {@code Method}, including
437 * type parameters. The string is formatted as the method access
438 * modifiers, if any, followed by an angle-bracketed
439 * comma-separated list of the method's type parameters, if any,
440 * followed by the method's generic return type, followed by a
573 * declaring the underlying method (or of a subclass
574 * or implementor thereof); if the number of actual
575 * and formal parameters differ; if an unwrapping
576 * conversion for primitive arguments fails; or if,
577 * after possible unwrapping, a parameter value
578 * cannot be converted to the corresponding formal
579 * parameter type by a method invocation conversion.
580 * @exception InvocationTargetException if the underlying method
581 * throws an exception.
582 * @exception NullPointerException if the specified object is null
583 * and the method is an instance method.
584 * @exception ExceptionInInitializerError if the initialization
585 * provoked by this method fails.
586 */
587 public Object invoke(Object obj, Object... args)
588 throws IllegalAccessException, IllegalArgumentException,
589 InvocationTargetException
590 {
591 if (!override) {
592 if (!Reflection.quickCheckMemberAccess(clazz, modifiers)) {
593 Class<?> caller = Reflection.getCallerClass(1);
594 Class<?> targetClass = ((obj == null || !Modifier.isProtected(modifiers))
595 ? clazz
596 : obj.getClass());
597
598 boolean cached;
599 synchronized (this) {
600 cached = (securityCheckCache == caller)
601 && (securityCheckTargetClassCache == targetClass);
602 }
603 if (!cached) {
604 Reflection.ensureMemberAccess(caller, clazz, obj, modifiers);
605 synchronized (this) {
606 securityCheckCache = caller;
607 securityCheckTargetClassCache = targetClass;
608 }
609 }
610 }
611 }
612 if (methodAccessor == null) acquireMethodAccessor();
613 return methodAccessor.invoke(obj, args);
614 }
685 }
686
687 /**
688 * @throws NullPointerException {@inheritDoc}
689 * @since 1.5
690 */
691 public <T extends Annotation> T getAnnotation(Class<T> annotationClass) {
692 if (annotationClass == null)
693 throw new NullPointerException();
694
695 return (T) declaredAnnotations().get(annotationClass);
696 }
697
698 /**
699 * @since 1.5
700 */
701 public Annotation[] getDeclaredAnnotations() {
702 return AnnotationParser.toArray(declaredAnnotations());
703 }
704
705 private transient Map<Class<? extends Annotation>, Annotation> declaredAnnotations;
706
707 private synchronized Map<Class<? extends Annotation>, Annotation> declaredAnnotations() {
708 if (declaredAnnotations == null) {
709 declaredAnnotations = AnnotationParser.parseAnnotations(
710 annotations, sun.misc.SharedSecrets.getJavaLangAccess().
711 getConstantPool(getDeclaringClass()),
712 getDeclaringClass());
713 }
714 return declaredAnnotations;
715 }
716
717 /**
718 * Returns the default value for the annotation member represented by
719 * this {@code Method} instance. If the member is of a primitive type,
720 * an instance of the corresponding wrapper type is returned. Returns
721 * null if no default is associated with the member, or if the method
722 * instance does not represent a declared member of an annotation type.
723 *
724 * @return the default value for the annotation member represented
725 * by this {@code Method} instance.
726 * @throws TypeNotPresentException if the annotation is of type
727 * {@link Class} and no definition can be found for the
728 * default class value.
729 * @since 1.5
730 */
731 public Object getDefaultValue() {
732 if (annotationDefault == null)
733 return null;
734 Class<?> memberType = AnnotationType.invocationHandlerReturnType(
735 getReturnType());
736 Object result = AnnotationParser.parseMemberValue(
737 memberType, ByteBuffer.wrap(annotationDefault),
738 sun.misc.SharedSecrets.getJavaLangAccess().
739 getConstantPool(getDeclaringClass()),
740 getDeclaringClass());
741 if (result instanceof sun.reflect.annotation.ExceptionProxy)
742 throw new AnnotationFormatError("Invalid default: " + this);
743 return result;
744 }
745
746 /**
747 * Returns an array of arrays that represent the annotations on the formal
748 * parameters, in declaration order, of the method represented by
749 * this {@code Method} object. (Returns an array of length zero if the
750 * underlying method is parameterless. If the method has one or more
751 * parameters, a nested array of length zero is returned for each parameter
752 * with no annotations.) The annotation objects contained in the returned
753 * arrays are serializable. The caller of this method is free to modify
754 * the returned arrays; it will have no effect on the arrays returned to
|