1/*
2 * ProGuard -- shrinking, optimization, obfuscation, and preverification
3 *             of Java bytecode.
4 *
5 * Copyright (c) 2002-2009 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.classfile.visitor;
22
23import proguard.classfile.*;
24import proguard.classfile.util.SimplifiedVisitor;
25
26/**
27 * This <code>MemberVisitor</code> delegates its visits to methods to
28 * another given <code>MemberVisitor</code>, but only when the visited
29 * method may have implementations.
30 *
31 * @see Clazz#mayHaveImplementations(Method)
32 * @author Eric Lafortune
33 */
34public class MethodImplementationFilter
35extends      SimplifiedVisitor
36implements   MemberVisitor
37{
38    private final MemberVisitor memberVisitor;
39
40
41    /**
42     * Creates a new MethodImplementationFilter.
43     * @param memberVisitor     the <code>MemberVisitor</code> to which
44     *                          visits will be delegated.
45     */
46    public MethodImplementationFilter(MemberVisitor memberVisitor)
47    {
48        this.memberVisitor = memberVisitor;
49    }
50
51
52    // Implementations for MemberVisitor.
53
54    public void visitProgramMethod(ProgramClass programClass, ProgramMethod programMethod)
55    {
56        if (programClass.mayHaveImplementations(programMethod))
57        {
58            memberVisitor.visitProgramMethod(programClass, programMethod);
59        }
60    }
61
62
63    public void visitLibraryMethod(LibraryClass libraryClass, LibraryMethod libraryMethod)
64    {
65        if (libraryClass.mayHaveImplementations(libraryMethod))
66        {
67            memberVisitor.visitLibraryMethod(libraryClass, libraryMethod);
68        }
69    }
70}
71