KickJava   Java API By Example, From Geeks To Geeks.

Java > Open Source Codes > proguard > classfile > visitor > DotClassClassVisitor


1 /*
2  * ProGuard -- shrinking, optimization, obfuscation, and preverification
3  * of Java bytecode.
4  *
5  * Copyright (c) 2002-2007 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  */
21 package proguard.classfile.visitor;
22
23 import proguard.classfile.*;
24 import proguard.classfile.attribute.CodeAttribute;
25 import proguard.classfile.constant.*;
26 import proguard.classfile.instruction.*;
27 import proguard.classfile.instruction.visitor.InstructionVisitor;
28 import proguard.classfile.util.*;
29 import proguard.classfile.constant.visitor.ConstantVisitor;
30 import proguard.util.ClassNameListMatcher;
31
32
33 /**
34  * This InstructionVisitor lets a given <code>ClassVisitor</code> visit all
35  * classes involved in any <code>.class</code> constructs that it visits.
36  * <p>
37  * Note that before JDK 1.5, <code>.class</code> constructs are actually
38  * compiled differently, using <code>Class.forName</code> constructs.
39  *
40  * @see ClassForNameClassVisitor
41  *
42  * @author Eric Lafortune
43  */
44 public class DotClassClassVisitor
45 extends SimplifiedVisitor
46 implements InstructionVisitor,
47              ConstantVisitor
48 {
49     private ClassVisitor classVisitor;
50
51
52     /**
53      * Creates a new ClassHierarchyTraveler.
54      * @param classVisitor the <code>ClassVisitor</code> to which visits will
55      * be delegated.
56      */
57     public DotClassClassVisitor(ClassVisitor classVisitor)
58     {
59         this.classVisitor = classVisitor;
60     }
61
62
63     // Implementations for InstructionVisitor.
64
65     public void visitAnyInstruction(Clazz clazz, Method method, CodeAttribute codeAttribute, int offset, Instruction instruction) {}
66
67
68     public void visitConstantInstruction(Clazz clazz, Method method, CodeAttribute codeAttribute, int offset, ConstantInstruction constantInstruction)
69     {
70         byte opcode = constantInstruction.opcode;
71
72         // Could this instruction be a .class construct?
73 if (opcode == InstructionConstants.OP_LDC ||
74             opcode == InstructionConstants.OP_LDC_W)
75         {
76             clazz.constantPoolEntryAccept(constantInstruction.constantIndex,
77                                           this);
78         }
79     }
80
81
82     // Implementations for ConstantVisitor.
83
84     public void visitAnyConstant(Clazz clazz, Constant constant) {}
85
86
87     public void visitClassConstant(Clazz clazz, ClassConstant classConstant)
88     {
89         // Visit the referenced class from the .class construct.
90 classConstant.referencedClassAccept(classVisitor);
91     }
92 }
93
Popular Tags