/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.lucene.util.mutable;

Base class for all mutable values.
@lucene.internal
/** * Base class for all mutable values. * * @lucene.internal */
public abstract class MutableValue implements Comparable<MutableValue> { public boolean exists = true; public abstract void copy(MutableValue source); public abstract MutableValue duplicate(); public abstract boolean equalsSameType(Object other); public abstract int compareSameType(Object other); public abstract Object toObject(); public boolean exists() { return exists; } @Override public int compareTo(MutableValue other) { Class<? extends MutableValue> c1 = this.getClass(); Class<? extends MutableValue> c2 = other.getClass(); if (c1 != c2) { int c = c1.hashCode() - c2.hashCode(); if (c == 0) { c = c1.getCanonicalName().compareTo(c2.getCanonicalName()); } return c; } return compareSameType(other); } @Override public boolean equals(Object other) { return (getClass() == other.getClass()) && this.equalsSameType(other); } @Override public abstract int hashCode(); @Override public String toString() { return exists() ? toObject().toString() : "(null)"; } }