01: /*
02: * ProGuard -- shrinking, optimization, obfuscation, and preverification
03: * of Java bytecode.
04: *
05: * Copyright (c) 2002-2007 Eric Lafortune (eric@graphics.cornell.edu)
06: *
07: * This library is free software; you can redistribute it and/or modify it
08: * under the terms of the GNU General Public License as published by the Free
09: * Software Foundation; either version 2 of the License, or (at your option)
10: * any later version.
11: *
12: * This library 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 Lesser General Public License
15: * for more details.
16: *
17: * You should have received a copy of the GNU Lesser General Public License
18: * along with this library; if not, write to the Free Software Foundation,
19: * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20: */
21: package proguard.classfile.attribute.preverification;
22:
23: import proguard.classfile.*;
24: import proguard.classfile.attribute.CodeAttribute;
25: import proguard.classfile.attribute.preverification.visitor.StackMapFrameVisitor;
26:
27: /**
28: * This StackMapFrame represents a "same frame" or a "same frame extended".
29: *
30: * @author Eric Lafortune
31: * @noinspection PointlessArithmeticExpression
32: */
33: public class SameZeroFrame extends StackMapFrame {
34: /**
35: * Creates an uninitialized SameZeroFrame.
36: */
37: public SameZeroFrame() {
38: }
39:
40: /**
41: * Creates a SameZeroFrame with the given tag.
42: */
43: public SameZeroFrame(int tag) {
44: u2offsetDelta = tag - SAME_ZERO_FRAME;
45: }
46:
47: // Implementations for StackMapFrame.
48:
49: public int getTag() {
50: return u2offsetDelta < 64 ? SAME_ZERO_FRAME + u2offsetDelta
51: : SAME_ZERO_FRAME_EXTENDED;
52: }
53:
54: public void accept(Clazz clazz, Method method,
55: CodeAttribute codeAttribute, int offset,
56: StackMapFrameVisitor stackMapFrameVisitor) {
57: stackMapFrameVisitor.visitSameZeroFrame(clazz, method,
58: codeAttribute, offset, this );
59: }
60:
61: // Implementations for Object.
62:
63: public String toString() {
64: return super .toString() + "Var: ..., Stack: (empty)";
65: }
66: }
|