    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 * Field reference constant pool entry.
    024 */
    025public class CPFieldRef extends ConstantPoolEntry {
    026
    027    CPClass className;
    028    transient int classNameIndex;
    029    private final CPNameAndType nameAndType;
    030    transient int nameAndTypeIndex;
    031
    032    public CPFieldRef(final CPClass className, final CPNameAndType descriptor, final int globalIndex) {
    033        super(ConstantPoolEntry.CP_Fieldref, globalIndex);
    034        this.className = className;
    035        this.nameAndType = descriptor;
    036    }
    037
    038    @Override
    039    protected ClassFileEntry[] getNestedClassFileEntries() {
    040        return new ClassFileEntry[] {className, nameAndType};
    041    }
    042
    043    @Override
    044    protected void resolve(final ClassConstantPool pool) {
    045        super.resolve(pool);
    046        nameAndTypeIndex = pool.indexOf(nameAndType);
    047        classNameIndex = pool.indexOf(className);
    048    }
    049
    050    @Override
    051    protected void writeBody(final DataOutputStream dos) throws IOException {
    052        dos.writeShort(classNameIndex);
    053        dos.writeShort(nameAndTypeIndex);
    054    }
    055
    056    @Override
    057    public String toString() {
    058        return "FieldRef: " + className + "#" + nameAndType;
    059    }
    060
    061    private boolean hashcodeComputed;
    062    private int cachedHashCode;
    063
    064    private void generateHashCode() {
    065        hashcodeComputed = true;
    066        final int PRIME = 31;
    067        int result = 1;
    068        result = PRIME * result + ((className == null) ? 0 : className.hashCode());
    069        result = PRIME * result + ((nameAndType == null) ? 0 : nameAndType.hashCode());
    070        cachedHashCode = result;
    071    }
    072
    073    @Override
    074    public int hashCode() {
    075        if (!hashcodeComputed) {
    076            generateHashCode();
    077        }
    078        return cachedHashCode;
    079    }
    080
    081    @Override
    082    public boolean equals(final Object obj) {
    083        if (this == obj) {
    084            return true;
    085        }
    086        if (obj == null) {
    087            return false;
    088        }
    089        if (getClass() != obj.getClass()) {
    090            return false;
    091        }
    092        final CPFieldRef other = (CPFieldRef) obj;
    093        if (className == null) {
    094            if (other.className != null) {
    095                return false;
    096            }
    097        } else if (!className.equals(other.className)) {
    098            return false;
    099        }
    100        if (nameAndType == null) {
    101            if (other.nameAndType != null) {
    102                return false;
    103            }
    104        } else if (!nameAndType.equals(other.nameAndType)) {
    105            return false;
    106        }
    107        return true;
    108    }
    109
    110}