1/*
2 * ProGuard -- shrinking, optimization, obfuscation, and preverification
3 *             of Java bytecode.
4 *
5 * Copyright (c) 2002-2013 Eric Lafortune (eric@graphics.cornell.edu)
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the Free
9 * Software Foundation; either version 2 of the License, or (at your option)
10 * any later version.
11 *
12 * This program is distributed in the hope that it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15 * more details.
16 *
17 * You should have received a copy of the GNU General Public License along
18 * with this program; if not, write to the Free Software Foundation, Inc.,
19 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 */
21package proguard.obfuscate;
22
23import proguard.classfile.*;
24import proguard.classfile.visitor.MemberVisitor;
25
26/**
27 * This <code>MemberVisitor</code> delegates its visits to another given
28 * <code>MemberVisitor</code>, but only when the visited member has a new name.
29 * Constructors are judged based on the class name.
30 *
31 * @see ClassObfuscator
32 * @see MemberObfuscator
33 *
34 * @author Eric Lafortune
35 */
36public class MemberNameFilter implements MemberVisitor
37{
38    private final MemberVisitor memberVisitor;
39
40
41    /**
42     * Creates a new MemberNameFilter.
43     * @param memberVisitor the <code>MemberVisitor</code> to which
44     *                      visits will be delegated.
45     */
46    public MemberNameFilter(MemberVisitor memberVisitor)
47    {
48        this.memberVisitor = memberVisitor;
49    }
50
51
52    // Implementations for MemberVisitor.
53
54    public void visitProgramField(ProgramClass programClass, ProgramField programField)
55    {
56        if (hasName(programField))
57        {
58            memberVisitor.visitProgramField(programClass, programField);
59        }
60    }
61
62
63    public void visitProgramMethod(ProgramClass programClass, ProgramMethod programMethod)
64    {
65        if (hasName(programClass, programMethod))
66        {
67            memberVisitor.visitProgramMethod(programClass, programMethod);
68        }
69    }
70
71
72    public void visitLibraryField(LibraryClass libraryClass, LibraryField libraryField)
73    {
74        if (hasName(libraryField))
75        {
76            memberVisitor.visitLibraryField(libraryClass, libraryField);
77        }
78    }
79
80
81    public void visitLibraryMethod(LibraryClass libraryClass, LibraryMethod libraryMethod)
82    {
83        if (hasName(libraryClass, libraryMethod))
84        {
85            memberVisitor.visitLibraryMethod(libraryClass, libraryMethod);
86        }
87    }
88
89
90    // Small utility methods.
91
92    /**
93     * Returns whether the given class has a new name.
94     */
95    private boolean hasName(Clazz clazz)
96    {
97        return ClassObfuscator.newClassName(clazz) != null;
98    }
99
100
101    /**
102     * Returns whether the given method has a new name.
103     */
104    private boolean hasName(Clazz clazz, Method method)
105    {
106        return
107            hasName(method) ||
108            (hasName(clazz) &&
109             method.getName(clazz).equals(ClassConstants.INTERNAL_METHOD_NAME_INIT));
110    }
111
112
113    /**
114     * Returns whether the given class member has a new name.
115     */
116    private boolean hasName(Member member)
117    {
118        return MemberObfuscator.newMemberName(member) != null;
119    }
120}
121