com.twitter.heron.api.Pair Maven / Gradle / Ivy
// Copyright 2017 Twitter. All rights reserved.
//
// 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.
/**
* 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 com.twitter.heron.api;
import java.io.Serializable;
/**
* A pair of values.
*
* @param the type of the first value
* @param the type of the second value
*/
public final class Pair implements Serializable {
private static final long serialVersionUID = 3926373357946515821L;
/**
* The first value
*/
private final T1 first;
/**
* The second value
*/
private final T2 second;
/**
* Constructs a new pair of values
*
* @param first the first value
* @param second the second value
*/
private Pair(T1 first, T2 second) {
this.first = first;
this.second = second;
}
/**
* Returns the first value in a pair.
*
* @return the first value
*/
public T1 getFirst() {
return first;
}
/**
* Returns the second value in a pair.
*
* @return the second value
*/
public T2 getSecond() {
return second;
}
/**
* Constructs a new pair of values.
*
* @param first the first value
* @param second the second value
* @param the type of the first value
* @param the type of the second value
* @return a new pair of values
*/
public static Pair of(T1 first, T2 second) {
return new Pair<>(first, second);
}
@Override
public boolean equals(Object o) {
if (this == o) {
return true;
}
if (o == null || getClass() != o.getClass()) {
return false;
}
Pair pair = (Pair) o;
if (first != null ? !first.equals(pair.first) : pair.first != null) {
return false;
}
return second != null ? second.equals(pair.second) : pair.second == null;
}
@Override
public int hashCode() {
int result = first != null ? first.hashCode() : 0;
result = 31 * result + (second != null ? second.hashCode() : 0);
return result;
}
@Override
public String toString() {
return "(" + first + ", " + second + ')';
}
}