001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *   https://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied.  See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 */
019package org.apache.bcel.classfile;
020
021import java.io.DataInput;
022import java.io.DataOutputStream;
023import java.io.IOException;
024
025import org.apache.bcel.Const;
026
027/**
028 * This class is derived from the abstract {@link Constant} and represents a reference to a method type.
029 *
030 * @see Constant
031 * @since 6.0
032 */
033public final class ConstantMethodType extends Constant {
034
035    private int descriptorIndex;
036
037    /**
038     * Initialize from another object.
039     *
040     * @param c Source to copy.
041     */
042    public ConstantMethodType(final ConstantMethodType c) {
043        this(c.getDescriptorIndex());
044    }
045
046    /**
047     * Initialize instance from file data.
048     *
049     * @param file Input stream.
050     * @throws IOException if an I/O error occurs.
051     */
052    ConstantMethodType(final DataInput file) throws IOException {
053        this(file.readUnsignedShort());
054    }
055
056    /**
057     * Constructs a ConstantMethodType.
058     *
059     * @param descriptorIndex Index to the method descriptor.
060     */
061    public ConstantMethodType(final int descriptorIndex) {
062        super(Const.CONSTANT_MethodType);
063        this.descriptorIndex = descriptorIndex;
064    }
065
066    /**
067     * Called by objects that are traversing the nodes of the tree implicitly defined by the contents of a Java class. I.e.,
068     * the hierarchy of methods, fields, attributes, etc. spawns a tree of objects.
069     *
070     * @param v Visitor object.
071     */
072    @Override
073    public void accept(final Visitor v) {
074        v.visitConstantMethodType(this);
075    }
076
077    /**
078     * Dumps name and signature index to file stream in binary format.
079     *
080     * @param file Output file stream.
081     * @throws IOException if an I/O error occurs.
082     */
083    @Override
084    public void dump(final DataOutputStream file) throws IOException {
085        file.writeByte(super.getTag());
086        file.writeShort(descriptorIndex);
087    }
088
089    /**
090     * Gets the descriptor index.
091     *
092     * @return the descriptor index.
093     */
094    public int getDescriptorIndex() {
095        return descriptorIndex;
096    }
097
098    /**
099     * Sets the descriptor index.
100     *
101     * @param descriptorIndex the descriptor index.
102     */
103    public void setDescriptorIndex(final int descriptorIndex) {
104        this.descriptorIndex = descriptorIndex;
105    }
106
107    /**
108     * @return String representation.
109     */
110    @Override
111    public String toString() {
112        return super.toString() + "(descriptorIndex = " + descriptorIndex + ")";
113    }
114}