AbstractMapEntry.java
- /*
- * 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.commons.collections4.keyvalue;
- import java.util.Map;
- import java.util.Objects;
- /**
- * Abstract Pair class to assist with creating correct
- * {@link java.util.Map.Entry Map.Entry} implementations.
- *
- * @param <K> the type of keys
- * @param <V> the type of mapped values
- * @since 3.0
- */
- public abstract class AbstractMapEntry<K, V> extends AbstractKeyValue<K, V> implements Map.Entry<K, V> {
- /**
- * Constructs a new entry with the given key and given value.
- *
- * @param key the key for the entry, may be null
- * @param value the value for the entry, may be null
- */
- protected AbstractMapEntry(final K key, final V value) {
- super(key, value);
- }
- /**
- * Compares this {@code Map.Entry} with another {@code Map.Entry}.
- * <p>
- * Implemented per API documentation of {@link java.util.Map.Entry#equals(Object)}
- *
- * @param obj the object to compare to
- * @return true if equal key and value
- */
- @Override
- public boolean equals(final Object obj) {
- if (obj == this) {
- return true;
- }
- if (!(obj instanceof Map.Entry)) {
- return false;
- }
- final Map.Entry<?, ?> other = (Map.Entry<?, ?>) obj;
- return Objects.equals(getKey(), other.getKey()) &&
- Objects.equals(getValue(), other.getValue());
- }
- /**
- * Gets a hashCode compatible with the equals method.
- * <p>
- * Implemented per API documentation of {@link java.util.Map.Entry#hashCode()}
- *
- * @return a suitable hash code
- */
- @Override
- public int hashCode() {
- return (getKey() == null ? 0 : getKey().hashCode()) ^
- (getValue() == null ? 0 : getValue().hashCode());
- }
- /**
- * Sets the value stored in this {@code Map.Entry}.
- * <p>
- * This {@code Map.Entry} is not connected to a Map, so only the
- * local data is changed.
- *
- * @param value the new value
- * @return the previous value
- */
- @Override
- public V setValue(final V value) { // NOPMD
- return super.setValue(value);
- }
- }