    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 * @version $Id$
    032 */
    033public class MULTIANEWARRAY extends CPInstruction implements LoadClass, AllocationInstruction,
    034        ExceptionThrower {
    035
    036    private short dimensions;
    037
    038
    039    /**
    040     * Empty constructor needed for Instruction.readInstruction.
    041     * Not to be used otherwise.
    042     */
    043    MULTIANEWARRAY() {
    044    }
    045
    046
    047    public MULTIANEWARRAY(final int index, final short dimensions) {
    048        super(org.apache.bcel.Const.MULTIANEWARRAY, index);
    049        if (dimensions < 1) {
    050            throw new ClassGenException("Invalid dimensions value: " + dimensions);
    051        }
    052        this.dimensions = dimensions;
    053        super.setLength(4);
    054    }
    055
    056
    057    /**
    058     * Dump instruction as byte code to stream out.
    059     * @param out Output stream
    060     */
    061    @Override
    062    public void dump( final DataOutputStream out ) throws IOException {
    063        out.writeByte(super.getOpcode());
    064        out.writeShort(super.getIndex());
    065        out.writeByte(dimensions);
    066    }
    067
    068
    069    /**
    070     * Read needed data (i.e., no. dimension) from file.
    071     */
    072    @Override
    073    protected void initFromFile( final ByteSequence bytes, final boolean wide ) throws IOException {
    074        super.initFromFile(bytes, wide);
    075        dimensions = bytes.readByte();
    076        super.setLength(4);
    077    }
    078
    079
    080    /**
    081     * @return number of dimensions to be created
    082     */
    083    public final short getDimensions() {
    084        return dimensions;
    085    }
    086
    087
    088    /**
    089     * @return mnemonic for instruction
    090     */
    091    @Override
    092    public String toString( final boolean verbose ) {
    093        return super.toString(verbose) + " " + super.getIndex() + " " + dimensions;
    094    }
    095
    096
    097    /**
    098     * @return mnemonic for instruction with symbolic references resolved
    099     */
    100    @Override
    101    public String toString( final ConstantPool cp ) {
    102        return super.toString(cp) + " " + dimensions;
    103    }
    104
    105
    106    /**
    107     * Also works for instructions whose stack effect depends on the
    108     * constant pool entry they reference.
    109     * @return Number of words consumed from stack by this instruction
    110     */
    111    @Override
    112    public int consumeStack( final ConstantPoolGen cpg ) {
    113        return dimensions;
    114    }
    115
    116
    117    @Override
    118    public Class<?>[] getExceptions() {
    119        return ExceptionConst.createExceptions(ExceptionConst.EXCS.EXCS_CLASS_AND_INTERFACE_RESOLUTION,
    120            ExceptionConst.ILLEGAL_ACCESS_ERROR,
    121            ExceptionConst.NEGATIVE_ARRAY_SIZE_EXCEPTION);
    122    }
    123
    124
    125    @Override
    126    public ObjectType getLoadClassType( final ConstantPoolGen cpg ) {
    127        Type t = getType(cpg);
    128        if (t instanceof ArrayType) {
    129            t = ((ArrayType) t).getBasicType();
    130        }
    131        return (t instanceof ObjectType) ? (ObjectType) t : null;
    132    }
    133
    134
    135    /**
    136     * Call corresponding visitor method(s). The order is:
    137     * Call visitor methods of implemented interfaces first, then
    138     * call methods according to the class hierarchy in descending order,
    139     * i.e., the most specific visitXXX() call comes last.
    140     *
    141     * @param v Visitor object
    142     */
    143    @Override
    144    public void accept( final Visitor v ) {
    145        v.visitLoadClass(this);
    146        v.visitAllocationInstruction(this);
    147        v.visitExceptionThrower(this);
    148        v.visitTypedInstruction(this);
    149        v.visitCPInstruction(this);
    150        v.visitMULTIANEWARRAY(this);
    151    }
    152}