1 /*
2 * Copyright (c) 2012, 2013, 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.invoke;
27
28 import java.security.*;
29 import java.lang.reflect.*;
30 import java.lang.invoke.MethodHandles.Lookup;
31
32 /*
33 * Auxiliary to MethodHandleInfo, wants to nest in MethodHandleInfo but must be non-public.
34 */
35 /*non-public*/
36 final
37 class InfoFromMemberName implements MethodHandleInfo {
38 private final MemberName member;
39 private final int referenceKind;
40
41 InfoFromMemberName(Lookup lookup, MemberName member, byte referenceKind) {
42 assert(member.isResolved() || member.isMethodHandleInvoke() || member.isVarHandleMethodInvoke());
43 assert(member.referenceKindIsConsistentWith(referenceKind));
44 this.member = member;
45 this.referenceKind = referenceKind;
46 }
47
48 @Override
49 public Class<?> getDeclaringClass() {
50 return member.getDeclaringClass();
51 }
52
53 @Override
54 public String getName() {
55 return member.getName();
56 }
57
58 @Override
59 public MethodType getMethodType() {
60 return member.getMethodOrFieldType();
61 }
62
63 @Override
64 public int getModifiers() {
65 return member.getModifiers();
66 }
67
68 @Override
69 public int getReferenceKind() {
70 return referenceKind;
71 }
72
73 @Override
74 public String toString() {
75 return MethodHandleInfo.toString(getReferenceKind(), getDeclaringClass(), getName(), getMethodType());
76 }
77
78 @Override
79 public <T extends Member> T reflectAs(Class<T> expected, Lookup lookup) {
80 if ((member.isMethodHandleInvoke() || member.isVarHandleMethodInvoke())
81 && !member.isVarargs()) {
82 // This member is an instance of a signature-polymorphic method, which cannot be reflected
83 // A method handle invoker can come in either of two forms:
84 // A generic placeholder (present in the source code, and varargs)
85 // and a signature-polymorphic instance (synthetic and not varargs).
86 // For more information see comments on {@link MethodHandleNatives#linkMethod}.
87 throw new IllegalArgumentException("cannot reflect signature polymorphic method");
88 }
89 Member mem = AccessController.doPrivileged(new PrivilegedAction<>() {
90 public Member run() {
91 try {
92 return reflectUnchecked();
93 } catch (ReflectiveOperationException ex) {
94 throw new IllegalArgumentException(ex);
95 }
96 }
97 });
98 try {
99 Class<?> defc = getDeclaringClass();
100 byte refKind = (byte) getReferenceKind();
101 lookup.checkAccess(refKind, defc, convertToMemberName(refKind, mem));
102 } catch (IllegalAccessException ex) {
103 throw new IllegalArgumentException(ex);
104 }
105 return expected.cast(mem);
106 }
107
108 private Member reflectUnchecked() throws ReflectiveOperationException {
109 byte refKind = (byte) getReferenceKind();
110 Class<?> defc = getDeclaringClass();
111 boolean isPublic = Modifier.isPublic(getModifiers());
112 if (member.isObjectConstructorOrStaticInitMethod()) {
113 MethodType methodType = getMethodType();
114 if (MethodHandleNatives.refKindIsObjectConstructor(refKind) &&
115 methodType.returnType() != void.class) {
116 // object constructor
117 throw new IllegalArgumentException("object constructor must be of void return type");
118 } else if (MethodHandleNatives.refKindIsMethod(refKind) &&
119 methodType.returnType() != defc.asPrimaryType()) {
120 // static init factory
121 throw new IllegalArgumentException("static constructor must be of " + getDeclaringClass().getName());
122 }
123
124 return isPublic ? defc.getConstructor(methodType.parameterArray())
125 : defc.getDeclaredConstructor(methodType.parameterArray());
126 } else if (MethodHandleNatives.refKindIsMethod(refKind)) {
127 if (isPublic)
128 return defc.getMethod(getName(), getMethodType().parameterArray());
129 else
130 return defc.getDeclaredMethod(getName(), getMethodType().parameterArray());
131 } else if (MethodHandleNatives.refKindIsField(refKind)) {
132 if (isPublic)
133 return defc.getField(getName());
134 else
135 return defc.getDeclaredField(getName());
136 } else {
137 throw new IllegalArgumentException("referenceKind="+refKind);
138 }
139 }
140
141 private static MemberName convertToMemberName(byte refKind, Member mem) throws IllegalAccessException {
142 if (mem instanceof Method) {
143 boolean wantSpecial = (refKind == REF_invokeSpecial);
144 return new MemberName((Method) mem, wantSpecial);
145 } else if (mem instanceof Constructor) {
146 return new MemberName((Constructor) mem);
147 } else if (mem instanceof Field) {
148 boolean isSetter = (refKind == REF_putField || refKind == REF_putStatic);
149 return new MemberName((Field) mem, isSetter);
150 }
151 throw new InternalError(mem.getClass().getName());
152 }
153 }