    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    public ConstantMethodHandle(final ConstantMethodHandle c) {
    040        this(c.getReferenceKind(), c.getReferenceIndex());
    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    ConstantMethodHandle(final DataInput file) throws IOException {
    050        this(file.readUnsignedByte(), file.readUnsignedShort());
    051    }
    052
    053    public ConstantMethodHandle(final int referenceKind, final int referenceIndex) {
    054        super(Const.CONSTANT_MethodHandle);
    055        this.referenceKind = referenceKind;
    056        this.referenceIndex = referenceIndex;
    057    }
    058
    059    /**
    060     * Called by objects that are traversing the nodes of the tree implicitly defined by the contents of a Java class. I.e.,
    061     * the hierarchy of methods, fields, attributes, etc. spawns a tree of objects.
    062     *
    063     * @param v Visitor object
    064     */
    065    @Override
    066    public void accept(final Visitor v) {
    067        v.visitConstantMethodHandle(this);
    068    }
    069
    070    /**
    071     * Dump method kind and index to file stream in binary format.
    072     *
    073     * @param file Output file stream
    074     * @throws IOException if an I/O error occurs.
    075     */
    076    @Override
    077    public void dump(final DataOutputStream file) throws IOException {
    078        file.writeByte(super.getTag());
    079        file.writeByte(referenceKind);
    080        file.writeShort(referenceIndex);
    081    }
    082
    083    public int getReferenceIndex() {
    084        return referenceIndex;
    085    }
    086
    087    public int getReferenceKind() {
    088        return referenceKind;
    089    }
    090
    091    public void setReferenceIndex(final int referenceIndex) {
    092        this.referenceIndex = referenceIndex;
    093    }
    094
    095    public void setReferenceKind(final int referenceKind) {
    096        this.referenceKind = referenceKind;
    097    }
    098
    099    /**
    100     * @return String representation
    101     */
    102    @Override
    103    public String toString() {
    104        return super.toString() + "(referenceKind = " + referenceKind + ", referenceIndex = " + referenceIndex + ")";
    105    }
    106}