    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;
    021import java.util.Objects;
    022
    023/**
    024 * UTF8 constant pool entry, used for storing long Strings.
    025 */
    026public class CPUTF8 extends ConstantPoolEntry {
    027
    028    private final String utf8;
    029
    030    private boolean hashCodeComputed;
    031
    032    private int cachedHashCode;
    033
    034    public CPUTF8(final String string) {
    035        this(string, -1);
    036    }
    037
    038    /**
    039     * Creates a new CPUTF8 instance
    040     *
    041     * @param utf8 TODO
    042     * @param globalIndex - index in CpBands
    043     * @throws NullPointerException if utf8 is null
    044     */
    045    public CPUTF8(final String utf8, final int globalIndex) {
    046        super(ConstantPoolEntry.CP_UTF8, globalIndex);
    047        this.utf8 = Objects.requireNonNull(utf8, "utf8");
    048    }
    049    @Override
    050    public boolean equals(final Object obj) {
    051        if (this == obj) {
    052            return true;
    053        }
    054        if (obj == null) {
    055            return false;
    056        }
    057        if (this.getClass() != obj.getClass()) {
    058            return false;
    059        }
    060        final CPUTF8 other = (CPUTF8) obj;
    061        return utf8.equals(other.utf8);
    062    }
    063
    064    private void generateHashCode() {
    065        hashCodeComputed = true;
    066        final int PRIME = 31;
    067        cachedHashCode = PRIME + utf8.hashCode();
    068    }
    069
    070    @Override
    071    public int hashCode() {
    072        if (!hashCodeComputed) {
    073            generateHashCode();
    074        }
    075        return cachedHashCode;
    076    }
    077
    078    public void setGlobalIndex(final int index) {
    079        globalIndex = index;
    080    }
    081
    082    @Override
    083    public String toString() {
    084        return "UTF8: " + utf8;
    085    }
    086
    087    public String underlyingString() {
    088        return utf8;
    089    }
    090
    091    @Override
    092    protected void writeBody(final DataOutputStream dos) throws IOException {
    093        dos.writeUTF(utf8);
    094    }
    095}