package org.lsst.ccs.utilities.structs;
   
   import java.io.Serializable;
   import java.util.Map;
   
   /**
    * A simple tuple with two immutable values. can be used as a Map.Entry
    * @author bamade
    */
  // Date: 17/11/12
  
  public class UniquePair<K, V> implements Map.Entry<K, V>, Serializable {
      public final K key;
      public final V value;
  
      public UniquePair(K key, V value) {
          this.key = key;
          this.value = value;
      }
  
      @Override
      public K getKey() {
          return key;
      }
  
      @Override
      public V getValue() {
          return value;
      }
  
      @Override
      public V setValue(V v) {
          throw new UnsupportedOperationException("no set on value");
      }
  
      @Override
      public String toString() {
          return "[" + key + "," + value + "]";
      }
  
      @Override
      public boolean equals(Object o) {
          if (this == o) return true;
          if (!(o instanceof UniquePair)) return false;
  
          UniquePair that = (UniquePair) o;
  
          if (key != null ? !key.equals(that.key) : that.key != null) return false;
  
          return true;
      }
  
      @Override
      public int hashCode() {
          return key != null ? key.hashCode() : 0;
      }
  }