Pair.java

/*******************************************************************************
 * Copyright (c) 2012-2013 CWI
 * 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:

 *   * Anya Helene Bagge - anya@ii.uib.no - UiB
*******************************************************************************/
package org.rascalmpl.interpreter.env;

/**
 * A simple Pair class
 * 
 * TODO: consider moving this class to another package
 * 
 * @param <T1> Type of first element
 * @param <T2> Type of second element
 */
public class Pair<T1, T2> {
	
	private final T1 first;
	private final T2 second;

	public Pair(T1 first, T2 second) {
		this.first = first;
		this.second = second;
	}

	/**
	 * @return First element of pair
	 */
	public T1 getFirst() {
		return first;
	}

	/**
	 * @return Second element of pair
	 */
	public T2 getSecond() {
		return 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;
	}

	@SuppressWarnings("rawtypes")
	@Override
	public boolean equals(Object obj) {
		if (this == obj)
			return true;
		if (obj == null)
			return false;
		if (getClass() != obj.getClass())
			return false;
		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;
	}

}