    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.ExceptionConst;
    024import org.apache.bcel.classfile.ConstantPool;
    025import org.apache.bcel.util.ByteSequence;
    026
    027/**
    028 * MULTIANEWARRAY - Create new mutidimensional array of references
    029 * <PRE>Stack: ..., count1, [count2, ...] -&gt; ..., arrayref</PRE>
    030 *
    031 */
    032public class MULTIANEWARRAY extends CPInstruction implements LoadClass, AllocationInstruction,
    033        ExceptionThrower {
    034
    035    private short dimensions;
    036
    037
    038    /**
    039     * Empty constructor needed for Instruction.readInstruction.
    040     * Not to be used otherwise.
    041     */
    042    MULTIANEWARRAY() {
    043    }
    044
    045
    046    public MULTIANEWARRAY(final int index, final short dimensions) {
    047        super(org.apache.bcel.Const.MULTIANEWARRAY, index);
    048        if (dimensions < 1) {
    049            throw new ClassGenException("Invalid dimensions value: " + dimensions);
    050        }
    051        this.dimensions = dimensions;
    052        super.setLength(4);
    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        out.writeByte(super.getOpcode());
    063        out.writeShort(super.getIndex());
    064        out.writeByte(dimensions);
    065    }
    066
    067
    068    /**
    069     * Read needed data (i.e., no. dimension) from file.
    070     */
    071    @Override
    072    protected void initFromFile( final ByteSequence bytes, final boolean wide ) throws IOException {
    073        super.initFromFile(bytes, wide);
    074        dimensions = bytes.readByte();
    075        super.setLength(4);
    076    }
    077
    078
    079    /**
    080     * @return number of dimensions to be created
    081     */
    082    public final short getDimensions() {
    083        return dimensions;
    084    }
    085
    086
    087    /**
    088     * @return mnemonic for instruction
    089     */
    090    @Override
    091    public String toString( final boolean verbose ) {
    092        return super.toString(verbose) + " " + super.getIndex() + " " + dimensions;
    093    }
    094
    095
    096    /**
    097     * @return mnemonic for instruction with symbolic references resolved
    098     */
    099    @Override
    100    public String toString( final ConstantPool cp ) {
    101        return super.toString(cp) + " " + dimensions;
    102    }
    103
    104
    105    /**
    106     * Also works for instructions whose stack effect depends on the
    107     * constant pool entry they reference.
    108     * @return Number of words consumed from stack by this instruction
    109     */
    110    @Override
    111    public int consumeStack( final ConstantPoolGen cpg ) {
    112        return dimensions;
    113    }
    114
    115
    116    @Override
    117    public Class<?>[] getExceptions() {
    118        return ExceptionConst.createExceptions(ExceptionConst.EXCS.EXCS_CLASS_AND_INTERFACE_RESOLUTION,
    119            ExceptionConst.ILLEGAL_ACCESS_ERROR,
    120            ExceptionConst.NEGATIVE_ARRAY_SIZE_EXCEPTION);
    121    }
    122
    123
    124    @Override
    125    public ObjectType getLoadClassType( final ConstantPoolGen cpg ) {
    126        Type t = getType(cpg);
    127        if (t instanceof ArrayType) {
    128            t = ((ArrayType) t).getBasicType();
    129        }
    130        return (t instanceof ObjectType) ? (ObjectType) t : null;
    131    }
    132
    133
    134    /**
    135     * Call corresponding visitor method(s). The order is:
    136     * Call visitor methods of implemented interfaces first, then
    137     * call methods according to the class hierarchy in descending order,
    138     * i.e., the most specific visitXXX() call comes last.
    139     *
    140     * @param v Visitor object
    141     */
    142    @Override
    143    public void accept( final Visitor v ) {
    144        v.visitLoadClass(this);
    145        v.visitAllocationInstruction(this);
    146        v.visitExceptionThrower(this);
    147        v.visitTypedInstruction(this);
    148        v.visitCPInstruction(this);
    149        v.visitMULTIANEWARRAY(this);
    150    }
    151}