    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 * Abstract super class for Fieldref, Methodref, InterfaceMethodref and InvokeDynamic constants.
    028 *
    029 * @see ConstantFieldref
    030 * @see ConstantMethodref
    031 * @see ConstantInterfaceMethodref
    032 * @see ConstantInvokeDynamic
    033 */
    034public abstract class ConstantCP extends Constant {
    035
    036    /**
    037     * References to the constants containing the class and the field signature
    038     */
    039    // Note that this field is used to store the
    040    // bootstrap_method_attr_index of a ConstantInvokeDynamic.
    041    /**
    042     * @deprecated (since 6.0) will be made private; do not access directly, use getter/setter
    043     */
    044    @java.lang.Deprecated
    045    protected int class_index; // TODO make private (has getter & setter)
    046    // This field has the same meaning for all subclasses.
    047
    048    /**
    049     * @deprecated (since 6.0) will be made private; do not access directly, use getter/setter
    050     */
    051    @java.lang.Deprecated
    052    protected int name_and_type_index; // TODO make private (has getter & setter)
    053
    054    /**
    055     * Initialize instance from file data.
    056     *
    057     * @param tag Constant type tag
    058     * @param file Input stream
    059     * @throws IOException if an I/O error occurs.
    060     */
    061    ConstantCP(final byte tag, final DataInput file) throws IOException {
    062        this(tag, file.readUnsignedShort(), file.readUnsignedShort());
    063    }
    064
    065    /**
    066     * @param classIndex Reference to the class containing the field
    067     * @param nameAndTypeIndex and the field signature
    068     */
    069    protected ConstantCP(final byte tag, final int classIndex, final int nameAndTypeIndex) {
    070        super(tag);
    071        this.class_index = classIndex;
    072        this.name_and_type_index = nameAndTypeIndex;
    073    }
    074
    075    /**
    076     * Initialize from another object.
    077     */
    078    public ConstantCP(final ConstantCP c) {
    079        this(c.getTag(), c.getClassIndex(), c.getNameAndTypeIndex());
    080    }
    081
    082    /**
    083     * Dump constant field reference to file stream in binary format.
    084     *
    085     * @param file Output file stream
    086     * @throws IOException if an I/O error occurs.
    087     */
    088    @Override
    089    public final void dump(final DataOutputStream file) throws IOException {
    090        file.writeByte(super.getTag());
    091        file.writeShort(class_index);
    092        file.writeShort(name_and_type_index);
    093    }
    094
    095    /**
    096     * @return Class this field belongs to.
    097     */
    098    public String getClass(final ConstantPool cp) {
    099        return cp.constantToString(class_index, Const.CONSTANT_Class);
    100    }
    101
    102    /**
    103     * @return Reference (index) to class this constant refers to.
    104     */
    105    public final int getClassIndex() {
    106        return class_index;
    107    }
    108
    109    /**
    110     * @return Reference (index) to signature of the field.
    111     */
    112    public final int getNameAndTypeIndex() {
    113        return name_and_type_index;
    114    }
    115
    116    /**
    117     * @param class_index points to Constant_class
    118     */
    119    public final void setClassIndex(final int class_index) {
    120        this.class_index = class_index;
    121    }
    122
    123    /**
    124     * @param nameAndTypeIndex points to Constant_NameAndType
    125     */
    126    public final void setNameAndTypeIndex(final int nameAndTypeIndex) {
    127        this.name_and_type_index = nameAndTypeIndex;
    128    }
    129
    130    /**
    131     * @return String representation.
    132     *
    133     *         not final as ConstantInvokeDynamic needs to modify
    134     */
    135    @Override
    136    public String toString() {
    137        return super.toString() + "(class_index = " + class_index + ", name_and_type_index = " + name_and_type_index + ")";
    138    }
    139}