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 */
018 package org.apache.bcel.generic;
019
020 import java.io.DataOutputStream;
021 import java.io.IOException;
022 import org.apache.bcel.util.ByteSequence;
023
024 /**
025 * LOOKUPSWITCH - Switch with unordered set of values
026 *
027 * @version $Id: LOOKUPSWITCH.java 1152072 2011-07-29 01:54:05Z dbrosius $
028 * @author <A HREF="mailto:m.dahm@gmx.de">M. Dahm</A>
029 * @see SWITCH
030 */
031 public class LOOKUPSWITCH extends Select {
032
033 private static final long serialVersionUID = -8263209830709467636L;
034
035
036 /**
037 * Empty constructor needed for the Class.newInstance() statement in
038 * Instruction.readInstruction(). Not to be used otherwise.
039 */
040 LOOKUPSWITCH() {
041 }
042
043
044 public LOOKUPSWITCH(int[] match, InstructionHandle[] targets, InstructionHandle defaultTarget) {
045 super(org.apache.bcel.Constants.LOOKUPSWITCH, match, targets, defaultTarget);
046 length = (short) (9 + match_length * 8); /* alignment remainder assumed
047 * 0 here, until dump time. */
048 fixed_length = length;
049 }
050
051
052 /**
053 * Dump instruction as byte code to stream out.
054 * @param out Output stream
055 */
056 @Override
057 public void dump( DataOutputStream out ) throws IOException {
058 super.dump(out);
059 out.writeInt(match_length); // npairs
060 for (int i = 0; i < match_length; i++) {
061 out.writeInt(match[i]); // match-offset pairs
062 out.writeInt(indices[i] = getTargetOffset(targets[i]));
063 }
064 }
065
066
067 /**
068 * Read needed data (e.g. index) from file.
069 */
070 @Override
071 protected void initFromFile( ByteSequence bytes, boolean wide ) throws IOException {
072 super.initFromFile(bytes, wide); // reads padding
073 match_length = bytes.readInt();
074 fixed_length = (short) (9 + match_length * 8);
075 length = (short) (fixed_length + padding);
076 match = new int[match_length];
077 indices = new int[match_length];
078 targets = new InstructionHandle[match_length];
079 for (int i = 0; i < match_length; i++) {
080 match[i] = bytes.readInt();
081 indices[i] = bytes.readInt();
082 }
083 }
084
085
086 /**
087 * Call corresponding visitor method(s). The order is:
088 * Call visitor methods of implemented interfaces first, then
089 * call methods according to the class hierarchy in descending order,
090 * i.e., the most specific visitXXX() call comes last.
091 *
092 * @param v Visitor object
093 */
094 @Override
095 public void accept( Visitor v ) {
096 v.visitVariableLengthInstruction(this);
097 v.visitStackConsumer(this);
098 v.visitBranchInstruction(this);
099 v.visitSelect(this);
100 v.visitLOOKUPSWITCH(this);
101 }
102 }