001/* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * https://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, 013 * software distributed under the License is distributed on an 014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 015 * KIND, either express or implied. See the License for the 016 * specific language governing permissions and limitations 017 * under the License. 018 */ 019package org.apache.bcel.generic; 020 021import java.io.DataOutputStream; 022import java.io.IOException; 023 024import org.apache.bcel.util.ByteSequence; 025 026/** 027 * TABLESWITCH - Switch within given range of values, i.e., low..high 028 * 029 * @see SWITCH 030 */ 031public class TABLESWITCH extends Select { 032 033 /** 034 * Empty constructor needed for Instruction.readInstruction. Not to be used otherwise. 035 */ 036 TABLESWITCH() { 037 } 038 039 /** 040 * @param match sorted array of match values, match[0] must be low value, match[match_length - 1] high value 041 * @param targets where to branch for matched values 042 * @param defaultTarget default branch 043 */ 044 public TABLESWITCH(final int[] match, final InstructionHandle[] targets, final InstructionHandle defaultTarget) { 045 super(org.apache.bcel.Const.TABLESWITCH, match, targets, defaultTarget); 046 /* Alignment remainder assumed 0 here, until dump time */ 047 final short length = (short) (13 + getMatchLength() * 4); 048 super.setLength(length); 049 setFixedLength(length); 050 } 051 052 /** 053 * Call corresponding visitor method(s). The order is: Call visitor methods of implemented interfaces first, then call 054 * methods according to the class hierarchy in descending order, i.e., the most specific visitXXX() call comes last. 055 * 056 * @param v Visitor object 057 */ 058 @Override 059 public void accept(final Visitor v) { 060 v.visitVariableLengthInstruction(this); 061 v.visitStackConsumer(this); 062 v.visitBranchInstruction(this); 063 v.visitSelect(this); 064 v.visitTABLESWITCH(this); 065 } 066 067 /** 068 * Dump instruction as byte code to stream out. 069 * 070 * @param out Output stream 071 */ 072 @Override 073 public void dump(final DataOutputStream out) throws IOException { 074 super.dump(out); 075 final int matchLength = getMatchLength(); 076 final int low = matchLength > 0 ? super.getMatch(0) : 0; 077 out.writeInt(low); 078 final int high = matchLength > 0 ? super.getMatch(matchLength - 1) : 0; 079 out.writeInt(high); 080 for (int i = 0; i < matchLength; i++) { 081 out.writeInt(setIndices(i, getTargetOffset(super.getTarget(i)))); 082 } 083 } 084 085 /** 086 * Reads needed data (for example index) from file. 087 */ 088 @Override 089 protected void initFromFile(final ByteSequence bytes, final boolean wide) throws IOException { 090 super.initFromFile(bytes, wide); 091 final int low = bytes.readInt(); 092 final int high = bytes.readInt(); 093 final int matchLength = high - low + 1; 094 setMatchLength(matchLength); 095 final short fixedLength = (short) (13 + matchLength * 4); 096 setFixedLength(fixedLength); 097 super.setLength((short) (fixedLength + super.getPadding())); 098 super.setMatches(new int[matchLength]); 099 super.setIndices(new int[matchLength]); 100 super.setTargets(new InstructionHandle[matchLength]); 101 for (int i = 0; i < matchLength; i++) { 102 super.setMatch(i, low + i); 103 super.setIndices(i, bytes.readInt()); 104 } 105 } 106}