Pair.java

/*******************************************************************************
 * Copyright (c) 2009, 2010 Fraunhofer IWU and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     Fraunhofer IWU - initial API and implementation
 *******************************************************************************/
package net.enilink.commons.util;

public class Pair<A, B> {
	private A first;
	private B second;

	public Pair() {
		this(null, null);
	}

	public Pair(A first, B second) {
		this.first = first;
		this.second = second;
	}

	public A getFirst() {
		return first;
	}

	public void setFirst(A first) {
		this.first = first;
	}

	public B getSecond() {
		return second;
	}

	public void setSecond(B second) {
		this.second = second;
	}

	@Override
	public int hashCode() {
		final int PRIME = 31;
		int result = 1;
		result = PRIME * result + ((first == null) ? 0 : first.hashCode());
		result = PRIME * result + ((second == null) ? 0 : second.hashCode());
		return result;
	}

	@Override
	public boolean equals(Object obj) {
		if (this == obj)
			return true;
		if (obj == null)
			return false;
		if (getClass() != obj.getClass())
			return false;
		final Pair<?, ?> other = (Pair<?, ?>) obj;
		if (first == null) {
			if (other.first != null)
				return false;
		} else if (!first.equals(other.first))
			return false;
		if (second == null) {
			if (other.second != null)
				return false;
		} else if (!second.equals(other.second))
			return false;
		return true;
	}

	@Override
	public String toString() {
		return new StringBuilder("(").append(first).append(", ").append(second)
				.append(")").toString();
	}
}