Asm.java revision 7fc8f90b7160e879143be5cfd6ea3df866398884 
1/*
2 * Copyright (C) 2014 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17import org.objectweb.asm.*;
18import org.objectweb.asm.tree.*;
19import java.io.*;
20import java.util.*;
21
22public class Asm {
23  /*
24
25  Overall class access flags:
26
27      0x0001 |  // public
28      0x0010 |  // final
29      0x0020 |  // super
30      0x0200 |  // interface
31      0x0400 |  // abstract
32      0x1000 |  // synthetic
33      0x2000 |  // annotation
34      0x4000 ;  // enum
35
36  */
37
38  public final static int INTERFACE_DEFINED_BITS =
39      0x0001 |  // public, may be set.
40      0x0010 |  // final, must not be set.
41      0x0020 |  // super, must not be set.
42      0x0200 |  // interface, must be set.
43      0x0400 |  // abstract, must be set.
44      0x1000 |  // synthetic, may be set.
45      0x2000 |  // annotation, may be set (annotation implies interface)
46      0x4000 ;  // enum, must not be set.
47
48  public final static int CLASS_DEFINED_BITS =
49      0x0001 |  // public, may be set.
50      0x0010 |  // final, may be set.
51      0x0020 |  // super, may be set.
52      0x0200 |  // interface, must not be set.
53      0x0400 |  // abstract, may be set.
54      0x1000 |  // synthetic, may be set.
55      0x2000 |  // annotation, must not be set.
56      0x4000 ;  // enum, may be set.
57
58  public final static int FIELD_DEFINED_BITS =
59       0x0001 |  // public
60       0x0002 |  // private
61       0x0004 |  // protected
62       0x0008 |  // static
63       0x0010 |  // final
64       0x0040 |  // volatile
65       0x0080 |  // transient
66       0x1000 |  // synthetic
67       0x4000 ;  // enum
68
69  public final static int METHOD_DEFINED_BITS =
70       0x0001 |  // public
71       0x0002 |  // private
72       0x0004 |  // protected
73       0x0008 |  // static
74       0x0010 |  // final
75       0x0020 |  // synchronized
76       0x0040 |  // bridge
77       0x0080 |  // varargs
78       0x0100 |  // native
79       0x0400 |  // abstract
80       0x0800 |  // strictfp
81       0x1000 ;  // synthetic
82
83  public static void main(String args[]) throws Exception {
84    modify("Inf");
85    modify("NonInf");
86  }
87
88  private static void modify(String clazz) throws Exception {
89    ClassNode classNode = new ClassNode();
90    ClassReader cr = new ClassReader(clazz);
91    cr.accept(classNode, 0);
92
93    modify(classNode);
94
95    ClassWriter cw = new ClassWriter(0);
96    classNode.accept(cw);
97    byte[] b = cw.toByteArray();
98    OutputStream out = new FileOutputStream(clazz + ".out");
99    out.write(b, 0, b.length);
100    out.close();
101  }
102
103  private static void modify(ClassNode classNode) throws Exception {
104    int classFlagsOr = 0xFFFF;
105    // Check whether classNode is an interface or class.
106    if ((classNode.access & Opcodes.ACC_INTERFACE) == 0) {
107      classFlagsOr ^= CLASS_DEFINED_BITS;
108    } else {
109      classFlagsOr ^= INTERFACE_DEFINED_BITS;
110    }
111    classNode.access |= classFlagsOr;
112
113    // Fields.
114    int fieldFlagsOr = 0xFFFF ^ FIELD_DEFINED_BITS;
115    for (FieldNode fieldNode : (List<FieldNode>)classNode.fields) {
116      fieldNode.access |= fieldFlagsOr;
117    }
118
119    // Methods.
120    int methodFlagsOr = 0xFFFF ^ METHOD_DEFINED_BITS;
121    for (MethodNode methodNode :(List<MethodNode>) classNode.methods) {
122      methodNode.access |= methodFlagsOr;
123    }
124  }
125}
126