Source code

    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 */
    017package org.apache.bcel.generic;
    018
    019import java.io.DataOutputStream;
    020import java.io.IOException;
    021
    022import org.apache.bcel.util.ByteSequence;
    023
    024/**
    025 * LOOKUPSWITCH - Switch with unordered set of values
    026 *
    027 * @see SWITCH
    028 */
    029public class LOOKUPSWITCH extends Select {
    030
    031    /**
    032     * Empty constructor needed for Instruction.readInstruction. Not to be used otherwise.
    033     */
    034    LOOKUPSWITCH() {
    035    }
    036
    037    public LOOKUPSWITCH(final int[] match, final InstructionHandle[] targets, final InstructionHandle defaultTarget) {
    038        super(org.apache.bcel.Const.LOOKUPSWITCH, match, targets, defaultTarget);
    039        /* alignment remainder assumed 0 here, until dump time. */
    040        final short length = (short) (9 + getMatchLength() * 8);
    041        super.setLength(length);
    042        setFixedLength(length);
    043    }
    044
    045    /**
    046     * Call corresponding visitor method(s). The order is: Call visitor methods of implemented interfaces first, then call
    047     * methods according to the class hierarchy in descending order, i.e., the most specific visitXXX() call comes last.
    048     *
    049     * @param v Visitor object
    050     */
    051    @Override
    052    public void accept(final Visitor v) {
    053        v.visitVariableLengthInstruction(this);
    054        v.visitStackConsumer(this);
    055        v.visitBranchInstruction(this);
    056        v.visitSelect(this);
    057        v.visitLOOKUPSWITCH(this);
    058    }
    059
    060    /**
    061     * Dump instruction as byte code to stream out.
    062     *
    063     * @param out Output stream
    064     */
    065    @Override
    066    public void dump(final DataOutputStream out) throws IOException {
    067        super.dump(out);
    068        final int matchLength = getMatchLength();
    069        out.writeInt(matchLength); // npairs
    070        for (int i = 0; i < matchLength; i++) {
    071            out.writeInt(super.getMatch(i)); // match-offset pairs
    072            out.writeInt(setIndices(i, getTargetOffset(super.getTarget(i))));
    073        }
    074    }
    075
    076    /**
    077     * Read needed data (e.g. index) from file.
    078     */
    079    @Override
    080    protected void initFromFile(final ByteSequence bytes, final boolean wide) throws IOException {
    081        super.initFromFile(bytes, wide); // reads padding
    082        final int matchLength = bytes.readInt();
    083        setMatchLength(matchLength);
    084        final short fixedLength = (short) (9 + matchLength * 8);
    085        setFixedLength(fixedLength);
    086        final short length = (short) (matchLength + super.getPadding());
    087        super.setLength(length);
    088        super.setMatches(new int[matchLength]);
    089        super.setIndices(new int[matchLength]);
    090        super.setTargets(new InstructionHandle[matchLength]);
    091        for (int i = 0; i < matchLength; i++) {
    092            super.setMatch(i, bytes.readInt());
    093            super.setIndices(i, bytes.readInt());
    094        }
    095    }
    096}