code: /*
   * Copyright 2015 recommenders.net.
   *
   * 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.
   */
  package net.recommenders.rival.evaluation;
  
  /**
   * Bean class to store an element of type A and another of type B.
   *
   * @param <A> The type of the first element in the pair.
   * @param <B> The type of the second element in the pair.
   *
   * @author <a href="http://github.com/abellogin">Alejandro</a>
   */
  public class Pair<A, B> {
  
      /**
       * First element.
       */
      private A first;
      /**
       * Second element.
       */
      private B second;
  
      /**
       * Default constructor.
       *
       * @param firstElement first element to store
       * @param secondElement second element to store
       */
      public Pair(final A firstElement, final B secondElement) {
          this.first = firstElement;
          this.second = secondElement;
      }
  
      /**
       * Gets the first element of the pair.
       *
       * @return the first element of the pair
       */
      public A getFirst() {
          return first;
      }
  
      /**
       * Gets the second element of the pair.
       *
       * @return the second element of the pair
       */
      public B getSecond() {
          return second;
      }
  }
  