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