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 * @version $Id: TABLESWITCH.java 1749603 2016-06-21 20:50:19Z ggregory $
029 * @see SWITCH
030 */
031public class TABLESWITCH extends Select {
032
033    /**
034     * Empty constructor needed for the Class.newInstance() statement in
035     * Instruction.readInstruction(). Not to be used otherwise.
036     */
037    TABLESWITCH() {
038    }
039
040
041    /**
042     * @param match sorted array of match values, match[0] must be low value, 
043     * match[match_length - 1] high value
044     * @param targets where to branch for matched values
045     * @param defaultTarget default branch
046     */
047    public TABLESWITCH(final int[] match, final InstructionHandle[] targets, final InstructionHandle defaultTarget) {
048        super(org.apache.bcel.Const.TABLESWITCH, match, targets, defaultTarget);
049        /* Alignment remainder assumed 0 here, until dump time */
050        final short _length = (short) (13 + getMatch_length() * 4);
051        super.setLength(_length);
052        setFixed_length(_length);
053    }
054
055
056    /**
057     * Dump instruction as byte code to stream out.
058     * @param out Output stream
059     */
060    @Override
061    public void dump( final DataOutputStream out ) throws IOException {
062        super.dump(out);
063        final int _match_length = getMatch_length();
064        final int low = (_match_length > 0) ? super.getMatch(0) : 0;
065        out.writeInt(low);
066        final int high = (_match_length > 0) ? super.getMatch(_match_length - 1) : 0;
067        out.writeInt(high);
068        for (int i = 0; i < _match_length; i++) {
069            out.writeInt(setIndices(i, getTargetOffset(super.getTarget(i))));
070        }
071    }
072
073
074    /**
075     * Read needed data (e.g. index) from file.
076     */
077    @Override
078    protected void initFromFile( final ByteSequence bytes, final boolean wide ) throws IOException {
079        super.initFromFile(bytes, wide);
080        final int low = bytes.readInt();
081        final int high = bytes.readInt();
082        final int _match_length = high - low + 1;
083        setMatch_length(_match_length);
084        final short _fixed_length = (short) (13 + _match_length * 4);
085        setFixed_length(_fixed_length);
086        super.setLength((short) (_fixed_length + super.getPadding()));
087        super.setMatches(new int[_match_length]);
088        super.setIndices(new int[_match_length]);
089        super.setTargets(new InstructionHandle[_match_length]);
090        for (int i = 0; i < _match_length; i++) {
091            super.setMatch(i, low + i);
092            super.setIndices(i, bytes.readInt());
093        }
094    }
095
096
097    /**
098     * Call corresponding visitor method(s). The order is:
099     * Call visitor methods of implemented interfaces first, then
100     * call methods according to the class hierarchy in descending order,
101     * i.e., the most specific visitXXX() call comes last.
102     *
103     * @param v Visitor object
104     */
105    @Override
106    public void accept( final Visitor v ) {
107        v.visitVariableLengthInstruction(this);
108        v.visitStackConsumer(this);
109        v.visitBranchInstruction(this);
110        v.visitSelect(this);
111        v.visitTABLESWITCH(this);
112    }
113}