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Diffstat (limited to 'src/proguard/classfile/instruction/LookUpSwitchInstruction.java')
-rw-r--r-- | src/proguard/classfile/instruction/LookUpSwitchInstruction.java | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/src/proguard/classfile/instruction/LookUpSwitchInstruction.java b/src/proguard/classfile/instruction/LookUpSwitchInstruction.java new file mode 100644 index 0000000..178cce5 --- /dev/null +++ b/src/proguard/classfile/instruction/LookUpSwitchInstruction.java @@ -0,0 +1,135 @@ +/* + * ProGuard -- shrinking, optimization, obfuscation, and preverification + * of Java bytecode. + * + * Copyright (c) 2002-2009 Eric Lafortune (eric@graphics.cornell.edu) + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the Free + * Software Foundation; either version 2 of the License, or (at your option) + * any later version. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ +package proguard.classfile.instruction; + +import proguard.classfile.*; +import proguard.classfile.attribute.CodeAttribute; +import proguard.classfile.instruction.visitor.InstructionVisitor; + +/** + * This Instruction represents a simple instruction without variable arguments + * or constant pool references. + * + * @author Eric Lafortune + */ +public class LookUpSwitchInstruction extends SwitchInstruction +{ + public int[] cases; + + + /** + * Creates an uninitialized LookUpSwitchInstruction. + */ + public LookUpSwitchInstruction() {} + + + /** + * Creates a new LookUpSwitchInstruction with the given arguments. + */ + public LookUpSwitchInstruction(byte opcode, + int defaultOffset, + int[] cases, + int[] jumpOffsets) + { + this.opcode = opcode; + this.defaultOffset = defaultOffset; + this.cases = cases; + this.jumpOffsets = jumpOffsets; + } + + + /** + * Copies the given instruction into this instruction. + * @param lookUpSwitchInstruction the instruction to be copied. + * @return this instruction. + */ + public LookUpSwitchInstruction copy(LookUpSwitchInstruction lookUpSwitchInstruction) + { + this.opcode = lookUpSwitchInstruction.opcode; + this.defaultOffset = lookUpSwitchInstruction.defaultOffset; + this.cases = lookUpSwitchInstruction.cases; + this.jumpOffsets = lookUpSwitchInstruction.jumpOffsets; + + return this; + } + + + // Implementations for Instruction. + + public Instruction shrink() + { + // There aren't any ways to shrink this instruction. + return this; + } + + protected void readInfo(byte[] code, int offset) + { + // Skip up to three padding bytes. + offset += -offset & 3; + + // Read the two 32-bit arguments. + defaultOffset = readInt(code, offset); offset += 4; + int jumpOffsetCount = readInt(code, offset); offset += 4; + + // Read the matches-offset pairs. + cases = new int[jumpOffsetCount]; + jumpOffsets = new int[jumpOffsetCount]; + + for (int index = 0; index < jumpOffsetCount; index++) + { + cases[index] = readInt(code, offset); offset += 4; + jumpOffsets[index] = readInt(code, offset); offset += 4; + } + } + + + protected void writeInfo(byte[] code, int offset) + { + // Write up to three padding bytes. + while ((offset & 3) != 0) + { + writeByte(code, offset++, 0); + } + + // Write the two 32-bit arguments. + writeInt(code, offset, defaultOffset); offset += 4; + writeInt(code, offset, cases.length); offset += 4; + + // Write the matches-offset pairs. + for (int index = 0; index < cases.length; index++) + { + writeInt(code, offset, cases[index]); offset += 4; + writeInt(code, offset, jumpOffsets[index]); offset += 4; + } + } + + + public int length(int offset) + { + return 1 + (-(offset+1) & 3) + 8 + cases.length * 8; + } + + + public void accept(Clazz clazz, Method method, CodeAttribute codeAttribute, int offset, InstructionVisitor instructionVisitor) + { + instructionVisitor.visitLookUpSwitchInstruction(clazz, method, codeAttribute, offset, this); + } +} |