org.apache.ctakes.ytex.kernel.OrderedPair Maven / Gradle / Ivy

Go to download
/**
 * 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.ctakes.ytex.kernel;

/**
 * simple pair class used for cache keys where the result is symmetric, e.g.
 * similarity measures. Order o1 and o2 so that the results of the comparison is
 * the same, regardless of the order of o1 and o2.
 * 
 * @author vijay
 * 
 * @param 
 */
public class OrderedPair> {
	private T o1;
	private T o2;

	public OrderedPair(T o1, T o2) {
		super();
		if (o1.compareTo(o2) <= 0) {
			this.o1 = o1;
			this.o2 = o2;
		} else {
			this.o1 = o2;
			this.o2 = o1;
		}
	}

	@Override
	public int hashCode() {
		final int prime = 31;
		int result = 1;
		result = prime * result + ((o1 == null) ? 0 : o1.hashCode());
		result = prime * result + ((o2 == null) ? 0 : o2.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;
		@SuppressWarnings("unchecked")
		OrderedPair other = (OrderedPair) obj;
		if (o1 == null) {
			if (other.o1 != null)
				return false;
		} else if (!o1.equals(other.o1))
			return false;
		if (o2 == null) {
			if (other.o2 != null)
				return false;
		} else if (!o2.equals(other.o2))
			return false;
		return true;
	}

}