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.classfile;
018
019import java.io.DataInput;
020import java.io.DataOutputStream;
021import java.io.IOException;
022
023import org.apache.bcel.Const;
024
025/**
026 * This class is derived from the abstract {@link Constant} and represents a reference to a method type.
027 *
028 * @see Constant
029 * @since 6.0
030 */
031public final class ConstantMethodType extends Constant {
032
033    private int descriptorIndex;
034
035    /**
036     * Initialize from another object.
037     */
038    public ConstantMethodType(final ConstantMethodType c) {
039        this(c.getDescriptorIndex());
040    }
041
042    /**
043     * Initialize instance from file data.
044     *
045     * @param file Input stream
046     * @throws IOException if an I/O error occurs.
047     */
048    ConstantMethodType(final DataInput file) throws IOException {
049        this(file.readUnsignedShort());
050    }
051
052    public ConstantMethodType(final int descriptorIndex) {
053        super(Const.CONSTANT_MethodType);
054        this.descriptorIndex = descriptorIndex;
055    }
056
057    /**
058     * Called by objects that are traversing the nodes of the tree implicitly defined by the contents of a Java class. I.e.,
059     * the hierarchy of methods, fields, attributes, etc. spawns a tree of objects.
060     *
061     * @param v Visitor object
062     */
063    @Override
064    public void accept(final Visitor v) {
065        v.visitConstantMethodType(this);
066    }
067
068    /**
069     * Dump name and signature index to file stream in binary format.
070     *
071     * @param file Output file stream
072     * @throws IOException if an I/O error occurs.
073     */
074    @Override
075    public void dump(final DataOutputStream file) throws IOException {
076        file.writeByte(super.getTag());
077        file.writeShort(descriptorIndex);
078    }
079
080    public int getDescriptorIndex() {
081        return descriptorIndex;
082    }
083
084    public void setDescriptorIndex(final int descriptorIndex) {
085        this.descriptorIndex = descriptorIndex;
086    }
087
088    /**
089     * @return String representation
090     */
091    @Override
092    public String toString() {
093        return super.toString() + "(descriptorIndex = " + descriptorIndex + ")";
094    }
095}