1/*
2 * ProGuard -- shrinking, optimization, obfuscation, and preverification
3 *             of Java bytecode.
4 *
5 * Copyright (c) 2002-2014 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.*;
24
25
26/**
27 * This <code>ClassVisitor</code> delegates its visits to another given
28 * <code>ClassVisitor</code>, but only when visiting classes that don't
29 * have any subclasses.
30 *
31 * @author Eric Lafortune
32 */
33public class BottomClassFilter implements ClassVisitor
34{
35    private final ClassVisitor classVisitor;
36
37
38    /**
39     * Creates a new ProgramClassFilter.
40     * @param classVisitor     the <code>ClassVisitor</code> to which visits
41     *                         will be delegated.
42     */
43    public BottomClassFilter(ClassVisitor classVisitor)
44    {
45        this.classVisitor = classVisitor;
46    }
47
48
49    // Implementations for ClassVisitor.
50
51    public void visitProgramClass(ProgramClass programClass)
52    {
53        // Is this a bottom class in the class hierarchy?
54        if (programClass.subClasses == null)
55        {
56            classVisitor.visitProgramClass(programClass);
57        }
58    }
59
60
61    public void visitLibraryClass(LibraryClass libraryClass)
62    {
63        // Is this a bottom class in the class hierarchy?
64        if (libraryClass.subClasses == null)
65        {
66            classVisitor.visitLibraryClass(libraryClass);
67        }
68    }
69}
70