    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 * UTF8 constant pool entry, used for storing long Strings.
    024 */
    025public class CPUTF8 extends ConstantPoolEntry {
    026
    027    private final String utf8;
    028
    029    /**
    030     * Creates a new CPUTF8 instance
    031     *
    032     * @param utf8 TODO
    033     * @param globalIndex - index in CpBands
    034     * @throws NullPointerException if utf8 is null
    035     */
    036    public CPUTF8(final String utf8, final int globalIndex) {
    037        super(ConstantPoolEntry.CP_UTF8, globalIndex);
    038        this.utf8 = utf8;
    039        if (utf8 == null) {
    040            throw new NullPointerException("Null arguments are not allowed");
    041        }
    042    }
    043
    044    public CPUTF8(final String string) {
    045        this(string, -1);
    046    }
    047
    048    @Override
    049    public boolean equals(final Object obj) {
    050        if (this == obj) {
    051            return true;
    052        }
    053        if (obj == null) {
    054            return false;
    055        }
    056        if (this.getClass() != obj.getClass()) {
    057            return false;
    058        }
    059        final CPUTF8 other = (CPUTF8) obj;
    060        return utf8.equals(other.utf8);
    061    }
    062
    063    private boolean hashcodeComputed;
    064    private int cachedHashCode;
    065
    066    private void generateHashCode() {
    067        hashcodeComputed = true;
    068        final int PRIME = 31;
    069        cachedHashCode = PRIME + utf8.hashCode();
    070    }
    071
    072    @Override
    073    public int hashCode() {
    074        if (!hashcodeComputed) {
    075            generateHashCode();
    076        }
    077        return cachedHashCode;
    078    }
    079
    080    @Override
    081    public String toString() {
    082        return "UTF8: " + utf8;
    083    }
    084
    085    @Override
    086    protected void writeBody(final DataOutputStream dos) throws IOException {
    087        dos.writeUTF(utf8);
    088    }
    089
    090    public String underlyingString() {
    091        return utf8;
    092    }
    093
    094    public void setGlobalIndex(final int index) {
    095        globalIndex = index;
    096    }
    097}