content: /*
   * Copyright (C) 2009 The Android Open Source Project
   *
   * 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 android.util;
  
  import java.util.Objects;
  
  /**
   * Container to ease passing around a tuple of two objects. This object provides a sensible
   * implementation of equals(), returning true if equals() is true on each of the contained
   * objects.
   */
  public class Pair<F, S> {
      public final F first;
      public final S second;
  
      /**
       * Constructor for a Pair.
       *
       * @param first the first object in the Pair
       * @param second the second object in the pair
       */
      public Pair(F first, S second) {
          this.first = first;
          this.second = second;
      }
  
      /**
       * Checks the two objects for equality by delegating to their respective
       * {@link Object#equals(Object)} methods.
       *
       * @param o the {@link Pair} to which this one is to be checked for equality
       * @return true if the underlying objects of the Pair are both considered
       *         equal
       */
      @Override
      public boolean equals(Object o) {
          if (!(o instanceof Pair)) {
              return false;
          }
          Pair<?, ?> p = (Pair<?, ?>) o;
          return Objects.equals(p.first, first) && Objects.equals(p.second, second);
      }
  
      /**
       * Compute a hash code using the hash codes of the underlying objects
       *
       * @return a hashcode of the Pair
       */
      @Override
      public int hashCode() {
          return (first == null ? 0 : first.hashCode()) ^ (second == null ? 0 : second.hashCode());
      }
  
      @Override
      public String toString() {
          return "Pair{" + String.valueOf(first) + " " + String.valueOf(second) + "}";
      }
  
      /**
       * Convenience method for creating an appropriately typed pair.
       * @param a the first object in the Pair
       * @param b the second object in the pair
       * @return a Pair that is templatized with the types of a and b
       */
      public static <A, B> Pair <A, B> create(A a, B b) {
          return new Pair<A, B>(a, b);
      }
  }
  