/* * ProGuard -- shrinking, optimization, obfuscation, and preverification * of Java bytecode. * * Copyright (c) 2002-2011 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 TableSwitchInstruction extends SwitchInstruction { public int lowCase; public int highCase; /** * Creates an uninitialized TableSwitchInstruction. */ public TableSwitchInstruction() {} /** * Creates a new TableSwitchInstruction with the given arguments. */ public TableSwitchInstruction(byte opcode, int defaultOffset, int lowCase, int highCase, int[] jumpOffsets) { this.opcode = opcode; this.defaultOffset = defaultOffset; this.lowCase = lowCase; this.highCase = highCase; this.jumpOffsets = jumpOffsets; } /** * Copies the given instruction into this instruction. * @param tableSwitchInstruction the instruction to be copied. * @return this instruction. */ public TableSwitchInstruction copy(TableSwitchInstruction tableSwitchInstruction) { this.opcode = tableSwitchInstruction.opcode; this.defaultOffset = tableSwitchInstruction.defaultOffset; this.lowCase = tableSwitchInstruction.lowCase; this.highCase = tableSwitchInstruction.highCase; this.jumpOffsets = tableSwitchInstruction.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 three 32-bit arguments. defaultOffset = readInt(code, offset); offset += 4; lowCase = readInt(code, offset); offset += 4; highCase = readInt(code, offset); offset += 4; // Read the jump offsets. jumpOffsets = new int[highCase - lowCase + 1]; for (int index = 0; index < jumpOffsets.length; index++) { 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 three 32-bit arguments. writeInt(code, offset, defaultOffset); offset += 4; writeInt(code, offset, lowCase); offset += 4; writeInt(code, offset, highCase); offset += 4; // Write the jump offsets. int length = highCase - lowCase + 1; for (int index = 0; index < length; index++) { writeInt(code, offset, jumpOffsets[index]); offset += 4; } } public int length(int offset) { return 1 + (-(offset+1) & 3) + 12 + (highCase - lowCase + 1) * 4; } public void accept(Clazz clazz, Method method, CodeAttribute codeAttribute, int offset, InstructionVisitor instructionVisitor) { instructionVisitor.visitTableSwitchInstruction(clazz, method, codeAttribute, offset, this); } }