001/**
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *      http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018
019package org.apache.oozie.util;
020
021import org.apache.commons.lang.ObjectUtils;
022
023/**
024 * Utility class for holding a pair of data
025 * @param <T> type of first data
026 * @param <S> type of second data
027 */
028public class Pair<T, S> {
029    private T first;
030    private S second;
031
032    public Pair(T first, S second) {
033        this.first = first;
034        this.second = second;
035    }
036
037
038    public static <T, S> Pair<T, S> of(T first, S second) {
039        return new Pair<T,S>(first, second);
040    }
041
042    public T getFirst() {
043        return first;
044    }
045
046    public S getSecond() {
047        return second;
048    }
049
050    public int hashCode()
051    {
052        return (first == null ? 1 : first.hashCode()) * 17 + (second == null ? 1 : second.hashCode()) * 19;
053    }
054
055    public boolean equals(Object other)
056    {
057        if (other == null) {
058            return false;
059        }
060
061        if (!(other instanceof Pair)) {
062            return false;
063        }
064
065        Pair<T, S> otherPair = (Pair<T,S>)other;
066        return (ObjectUtils.equals(first, otherPair.first) && ObjectUtils.equals(second, otherPair.second));
067    }
068}
069