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.classfile;
019
020import java.io.DataInput;
021import java.io.DataOutputStream;
022import java.io.IOException;
023
024import org.apache.bcel.Const;
025
026/**
027 * This class is derived from the abstract {@link Constant} and represents a reference to a method type.
028 *
029 * @see Constant
030 * @since 6.0
031 */
032public final class ConstantMethodType extends Constant {
033
034    private int descriptorIndex;
035
036    /**
037     * Initialize from another object.
038     */
039    public ConstantMethodType(final ConstantMethodType c) {
040        this(c.getDescriptorIndex());
041    }
042
043    /**
044     * Initialize instance from file data.
045     *
046     * @param file Input stream
047     * @throws IOException if an I/O error occurs.
048     */
049    ConstantMethodType(final DataInput file) throws IOException {
050        this(file.readUnsignedShort());
051    }
052
053    public ConstantMethodType(final int descriptor_index) {
054        super(Const.CONSTANT_MethodType);
055        this.descriptorIndex = descriptor_index;
056    }
057
058    /**
059     * Called by objects that are traversing the nodes of the tree implicitly defined by the contents of a Java class. I.e.,
060     * the hierarchy of methods, fields, attributes, etc. spawns a tree of objects.
061     *
062     * @param v Visitor object
063     */
064    @Override
065    public void accept(final Visitor v) {
066        v.visitConstantMethodType(this);
067    }
068
069    /**
070     * Dump name and signature index to file stream in binary format.
071     *
072     * @param file Output file stream
073     * @throws IOException if an I/O error occurs.
074     */
075    @Override
076    public void dump(final DataOutputStream file) throws IOException {
077        file.writeByte(super.getTag());
078        file.writeShort(descriptorIndex);
079    }
080
081    public int getDescriptorIndex() {
082        return descriptorIndex;
083    }
084
085    public void setDescriptorIndex(final int descriptor_index) {
086        this.descriptorIndex = descriptor_index;
087    }
088
089    /**
090     * @return String representation
091     */
092    @Override
093    public String toString() {
094        return super.toString() + "(descriptorIndex = " + descriptorIndex + ")";
095    }
096}