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