    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 handle.
    027 *
    028 * @see Constant
    029 * @since 6.0
    030 */
    031public final class ConstantMethodHandle extends Constant {
    032
    033    private int referenceKind;
    034    private int referenceIndex;
    035
    036    /**
    037     * Initialize from another object.
    038     *
    039     * @param c Source to copy.
    040     */
    041    public ConstantMethodHandle(final ConstantMethodHandle c) {
    042        this(c.getReferenceKind(), c.getReferenceIndex());
    043    }
    044
    045    /**
    046     * Initialize instance from file data.
    047     *
    048     * @param file Input stream
    049     * @throws IOException if an I/O error occurs.
    050     */
    051    ConstantMethodHandle(final DataInput file) throws IOException {
    052        this(file.readUnsignedByte(), file.readUnsignedShort());
    053    }
    054
    055    public ConstantMethodHandle(final int referenceKind, final int referenceIndex) {
    056        super(Const.CONSTANT_MethodHandle);
    057        this.referenceKind = referenceKind;
    058        this.referenceIndex = referenceIndex;
    059    }
    060
    061    /**
    062     * Called by objects that are traversing the nodes of the tree implicitly defined by the contents of a Java class. I.e.,
    063     * the hierarchy of methods, fields, attributes, etc. spawns a tree of objects.
    064     *
    065     * @param v Visitor object
    066     */
    067    @Override
    068    public void accept(final Visitor v) {
    069        v.visitConstantMethodHandle(this);
    070    }
    071
    072    /**
    073     * Dump method kind and index to file stream in binary format.
    074     *
    075     * @param file Output file stream
    076     * @throws IOException if an I/O error occurs.
    077     */
    078    @Override
    079    public void dump(final DataOutputStream file) throws IOException {
    080        file.writeByte(super.getTag());
    081        file.writeByte(referenceKind);
    082        file.writeShort(referenceIndex);
    083    }
    084
    085    public int getReferenceIndex() {
    086        return referenceIndex;
    087    }
    088
    089    public int getReferenceKind() {
    090        return referenceKind;
    091    }
    092
    093    public void setReferenceIndex(final int referenceIndex) {
    094        this.referenceIndex = referenceIndex;
    095    }
    096
    097    public void setReferenceKind(final int referenceKind) {
    098        this.referenceKind = referenceKind;
    099    }
    100
    101    /**
    102     * @return String representation
    103     */
    104    @Override
    105    public String toString() {
    106        return super.toString() + "(referenceKind = " + referenceKind + ", referenceIndex = " + referenceIndex + ")";
    107    }
    108}