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> lets a given <code>ClassVisitor</code>
28 * travel to the first concrete subclasses down in its hierarchy of abstract
29 * classes and concrete classes.
30 *
31 * @author Eric Lafortune
32 */
33public class ConcreteClassDownTraveler
34implements   ClassVisitor
35{
36    private final ClassVisitor classVisitor;
37
38
39    /**
40     * Creates a new ConcreteClassDownTraveler.
41     * @param classVisitor     the <code>ClassVisitor</code> to
42     *                         which visits will be delegated.
43     */
44    public ConcreteClassDownTraveler(ClassVisitor classVisitor)
45    {
46        this.classVisitor = classVisitor;
47    }
48
49
50    // Implementations for ClassVisitor.
51
52    public void visitProgramClass(ProgramClass programClass)
53    {
54        // Is this an abstract class or an interface?
55        if ((programClass.getAccessFlags() &
56             (ClassConstants.ACC_INTERFACE |
57              ClassConstants.ACC_ABSTRACT)) != 0)
58        {
59            // Travel down the hierarchy.
60            Clazz[] subClasses = programClass.subClasses;
61            if (subClasses != null)
62            {
63                for (int index = 0; index < subClasses.length; index++)
64                {
65                    subClasses[index].accept(this);
66                }
67            }
68        }
69        else
70        {
71            // Visit the class. Don't descend any further.
72            programClass.accept(classVisitor);
73        }
74    }
75
76
77    public void visitLibraryClass(LibraryClass libraryClass)
78    {
79        // Is this an abstract class or interface?
80        if ((libraryClass.getAccessFlags() &
81             (ClassConstants.ACC_INTERFACE |
82              ClassConstants.ACC_ABSTRACT)) != 0)
83        {
84            // Travel down the hierarchy.
85            Clazz[] subClasses = libraryClass.subClasses;
86            if (subClasses != null)
87            {
88                for (int index = 0; index < subClasses.length; index++)
89                {
90                    subClasses[index].accept(this);
91                }
92            }
93        }
94        else
95        {
96            // Visit the class. Don't descend any further.
97            libraryClass.accept(classVisitor);
98        }
99    }
100}
101