/* * Copyright (C) 2007 Google Inc. Licensed 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 com.google.common.collect; import java.util.Map.Entry; import com.google.common.base.Objects; /** * Implementation of the {@code equals}, {@code hashCode}, and {@code toString} * methods of {@code Entry}. * * @author Jared Levy */ abstract class AbstractMapEntry<K, V> implements Entry<K, V> { public abstract K getKey(); public abstract V getValue(); public V setValue(V value) { throw new UnsupportedOperationException(); } @Override public boolean equals(Object object) { if (object instanceof Entry) { Entry<?, ?> that = (Entry<?, ?>) object; return Objects.equal(this.getKey(), that.getKey()) && Objects.equal(this.getValue(), that.getValue()); } return false; } @Override public int hashCode() { K k = getKey(); V v = getValue(); return ((k == null) ? 0 : k.hashCode()) ^ ((v == null) ? 0 : v.hashCode()); } /** * Returns a string representation of the form <code>{key}={value}</code>. */ @Override public String toString() { return getKey() + "=" + getValue(); } }