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.optimize.evaluation;
22
23import proguard.classfile.*;
24import proguard.classfile.visitor.*;
25import proguard.optimize.info.SimpleEnumMarker;
26
27/**
28 * This ClassVisitor marks all program classes that it visits as simple enums,
29 * if their methods qualify.
30 *
31 * @author Eric Lafortune
32 */
33public class SimpleEnumClassChecker
34implements   ClassVisitor
35{
36    //*
37    private static final boolean DEBUG = false;
38    /*/
39    private static       boolean DEBUG = System.getProperty("enum") != null;
40    //*/
41
42
43    private final SimpleEnumMarker simpleEnumMarker     = new SimpleEnumMarker(true);
44    private final MemberVisitor    virtualMethodChecker = new MemberAccessFilter(0,
45                                                                                 ClassConstants.ACC_PRIVATE |
46                                                                                 ClassConstants.ACC_STATIC,
47                                                          new MemberToClassVisitor(
48                                                          new SimpleEnumMarker(false)));
49
50
51    // Implementations for ClassVisitor.
52
53    public void visitLibraryClass(LibraryClass libraryClass) {}
54
55    public void visitProgramClass(ProgramClass programClass)
56    {
57        // Does the class have the simple enum constructor?
58        if (programClass.findMethod(ClassConstants.METHOD_NAME_INIT,
59                                    ClassConstants.METHOD_TYPE_INIT_ENUM) != null)
60        {
61            if (DEBUG)
62            {
63                System.out.println("SimpleEnumClassChecker: ["+programClass.getName()+"] is a candidate simple enum, without extra fields");
64            }
65
66            // Mark it.
67            simpleEnumMarker.visitProgramClass(programClass);
68
69            // However, unmark it again if it has any non-private, non-static
70            // methods.
71            programClass.methodsAccept(virtualMethodChecker);
72        }
73    }
74}