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.ExceptionConst;
023import org.apache.bcel.classfile.ConstantPool;
024import org.apache.bcel.util.ByteSequence;
025
026/**
027 * MULTIANEWARRAY - Create new mutidimensional array of references
028 *
029 * <PRE>
030 * Stack: ..., count1, [count2, ...] -&gt; ..., arrayref
031 * </PRE>
032 */
033public class MULTIANEWARRAY extends CPInstruction implements LoadClass, AllocationInstruction, ExceptionThrower {
034
035    private short dimensions;
036
037    /**
038     * Empty constructor needed for Instruction.readInstruction. Not to be used otherwise.
039     */
040    MULTIANEWARRAY() {
041    }
042
043    public MULTIANEWARRAY(final int index, final short dimensions) {
044        super(org.apache.bcel.Const.MULTIANEWARRAY, index);
045        if (dimensions < 1) {
046            throw new ClassGenException("Invalid dimensions value: " + dimensions);
047        }
048        this.dimensions = dimensions;
049        super.setLength(4);
050    }
051
052    /**
053     * Call corresponding visitor method(s). The order is: Call visitor methods of implemented interfaces first, then call
054     * methods according to the class hierarchy in descending order, i.e., the most specific visitXXX() call comes last.
055     *
056     * @param v Visitor object
057     */
058    @Override
059    public void accept(final Visitor v) {
060        v.visitLoadClass(this);
061        v.visitAllocationInstruction(this);
062        v.visitExceptionThrower(this);
063        v.visitTypedInstruction(this);
064        v.visitCPInstruction(this);
065        v.visitMULTIANEWARRAY(this);
066    }
067
068    /**
069     * Also works for instructions whose stack effect depends on the constant pool entry they reference.
070     *
071     * @return Number of words consumed from stack by this instruction
072     */
073    @Override
074    public int consumeStack(final ConstantPoolGen cpg) {
075        return dimensions;
076    }
077
078    /**
079     * Dump instruction as byte code to stream out.
080     *
081     * @param out Output stream
082     */
083    @Override
084    public void dump(final DataOutputStream out) throws IOException {
085        out.writeByte(super.getOpcode());
086        out.writeShort(super.getIndex());
087        out.writeByte(dimensions);
088    }
089
090    /**
091     * @return number of dimensions to be created
092     */
093    public final short getDimensions() {
094        return dimensions;
095    }
096
097    @Override
098    public Class<?>[] getExceptions() {
099        return ExceptionConst.createExceptions(ExceptionConst.EXCS.EXCS_CLASS_AND_INTERFACE_RESOLUTION, ExceptionConst.ILLEGAL_ACCESS_ERROR,
100            ExceptionConst.NEGATIVE_ARRAY_SIZE_EXCEPTION);
101    }
102
103    @Override
104    public ObjectType getLoadClassType(final ConstantPoolGen cpg) {
105        Type t = getType(cpg);
106        if (t instanceof ArrayType) {
107            t = ((ArrayType) t).getBasicType();
108        }
109        return t instanceof ObjectType ? (ObjectType) t : null;
110    }
111
112    /**
113     * Read needed data (i.e., no. dimension) from file.
114     */
115    @Override
116    protected void initFromFile(final ByteSequence bytes, final boolean wide) throws IOException {
117        super.initFromFile(bytes, wide);
118        dimensions = bytes.readByte();
119        super.setLength(4);
120    }
121
122    /**
123     * @return mnemonic for instruction
124     */
125    @Override
126    public String toString(final boolean verbose) {
127        return super.toString(verbose) + " " + super.getIndex() + " " + dimensions;
128    }
129
130    /**
131     * @return mnemonic for instruction with symbolic references resolved
132     */
133    @Override
134    public String toString(final ConstantPool cp) {
135        return super.toString(cp) + " " + dimensions;
136    }
137}