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 * LOOKUPSWITCH - Switch with unordered set of values
027 *
028 * @see SWITCH
029 */
030public class LOOKUPSWITCH extends Select {
031
032    /**
033     * Empty constructor needed for Instruction.readInstruction.
034     * Not to be used otherwise.
035     */
036    LOOKUPSWITCH() {
037    }
038
039
040    public LOOKUPSWITCH(final int[] match, final InstructionHandle[] targets, final InstructionHandle defaultTarget) {
041        super(org.apache.bcel.Const.LOOKUPSWITCH, match, targets, defaultTarget);
042        /* alignment remainder assumed 0 here, until dump time. */
043        final short _length = (short) (9 + getMatch_length() * 8);
044        super.setLength(_length);
045        setFixed_length(_length);
046    }
047
048
049    /**
050     * Dump instruction as byte code to stream out.
051     * @param out Output stream
052     */
053    @Override
054    public void dump( final DataOutputStream out ) throws IOException {
055        super.dump(out);
056        final int _match_length = getMatch_length();
057        out.writeInt(_match_length); // npairs
058        for (int i = 0; i < _match_length; i++) {
059            out.writeInt(super.getMatch(i)); // match-offset pairs
060            out.writeInt(setIndices(i, getTargetOffset(super.getTarget(i))));
061        }
062    }
063
064
065    /**
066     * Read needed data (e.g. index) from file.
067     */
068    @Override
069    protected void initFromFile( final ByteSequence bytes, final boolean wide ) throws IOException {
070        super.initFromFile(bytes, wide); // reads padding
071        final int _match_length = bytes.readInt();
072        setMatch_length(_match_length);
073        final short _fixed_length = (short) (9 + _match_length * 8);
074        setFixed_length(_fixed_length);
075        final short _length = (short) (_match_length + super.getPadding());
076        super.setLength(_length);
077        super.setMatches(new int[_match_length]);
078        super.setIndices(new int[_match_length]);
079        super.setTargets(new InstructionHandle[_match_length]);
080        for (int i = 0; i < _match_length; i++) {
081            super.setMatch(i, bytes.readInt());
082            super.setIndices(i, bytes.readInt());
083        }
084    }
085
086
087    /**
088     * Call corresponding visitor method(s). The order is:
089     * Call visitor methods of implemented interfaces first, then
090     * call methods according to the class hierarchy in descending order,
091     * i.e., the most specific visitXXX() call comes last.
092     *
093     * @param v Visitor object
094     */
095    @Override
096    public void accept( final Visitor v ) {
097        v.visitVariableLengthInstruction(this);
098        v.visitStackConsumer(this);
099        v.visitBranchInstruction(this);
100        v.visitSelect(this);
101        v.visitLOOKUPSWITCH(this);
102    }
103}