    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.commons.compress.harmony.unpack200.bytecode;
    018
    019import java.io.DataOutputStream;
    020import java.io.IOException;
    021
    022/**
    023 * Abstract superclass for reference constant pool entries, such as a method or field reference.
    024 */
    025public abstract class CPRef extends ConstantPoolEntry {
    026
    027    CPClass className;
    028    transient int classNameIndex;
    029
    030    protected CPNameAndType nameAndType;
    031    transient int nameAndTypeIndex;
    032
    033    /**
    034     * Create a new CPRef
    035     *
    036     * @param type TODO
    037     * @param className TODO
    038     * @param descriptor TODO
    039     * @param globalIndex index in CpBands
    040     * @throws NullPointerException if descriptor or className is null
    041     */
    042    public CPRef(final byte type, final CPClass className, final CPNameAndType descriptor, final int globalIndex) {
    043        super(type, globalIndex);
    044        this.className = className;
    045        this.nameAndType = descriptor;
    046        if (descriptor == null || className == null) {
    047            throw new NullPointerException("Null arguments are not allowed");
    048        }
    049    }
    050
    051    @Override
    052    public boolean equals(final Object obj) {
    053        if (this == obj) {
    054            return true;
    055        }
    056        if (obj == null) {
    057            return false;
    058        }
    059        if (getClass() != obj.getClass()) {
    060            return false;
    061        }
    062        if (this.hashCode() != obj.hashCode()) {
    063            return false;
    064        }
    065        final CPRef other = (CPRef) obj;
    066        if (!className.equals(other.className)) {
    067            return false;
    068        }
    069        if (!nameAndType.equals(other.nameAndType)) {
    070            return false;
    071        }
    072        return true;
    073    }
    074
    075    @Override
    076    protected ClassFileEntry[] getNestedClassFileEntries() {
    077        final ClassFileEntry[] entries = new ClassFileEntry[2];
    078        entries[0] = className;
    079        entries[1] = nameAndType;
    080        return entries;
    081    }
    082
    083    @Override
    084    protected void resolve(final ClassConstantPool pool) {
    085        super.resolve(pool);
    086        nameAndTypeIndex = pool.indexOf(nameAndType);
    087        classNameIndex = pool.indexOf(className);
    088    }
    089
    090    protected String cachedToString;
    091
    092    @Override
    093    public String toString() {
    094        if (cachedToString == null) {
    095            String type;
    096            if (getTag() == ConstantPoolEntry.CP_Fieldref) {
    097                type = "FieldRef"; //$NON-NLS-1$
    098            } else if (getTag() == ConstantPoolEntry.CP_Methodref) {
    099                type = "MethoddRef"; //$NON-NLS-1$
    100            } else if (getTag() == ConstantPoolEntry.CP_InterfaceMethodref) {
    101                type = "InterfaceMethodRef"; //$NON-NLS-1$
    102            } else {
    103                type = "unknown"; //$NON-NLS-1$
    104            }
    105            cachedToString = type + ": " + className + "#" + nameAndType; //$NON-NLS-1$ //$NON-NLS-2$
    106        }
    107        return cachedToString;
    108    }
    109
    110    @Override
    111    protected void writeBody(final DataOutputStream dos) throws IOException {
    112        dos.writeShort(classNameIndex);
    113        dos.writeShort(nameAndTypeIndex);
    114    }
    115
    116}