Map.Entry<K,V> entry = new AbstractMap.BasicMapEntry<K, V>(k, v)
Map.Entry<K,V> entry = new AbstractMap.SimpleEntry<K, V>(k, v)
    public Set<Map.Entry<K, V>> entrySet()    {      if (entries == null)	{	  Map.Entry<K,V> entry = new AbstractMap.BasicMapEntry<K, V>(k, v)	  {	    /**	     * Sets the value of the map entry to the supplied value.	     * An exception is always thrown, as the map is immutable.	     *	     * @param o The new value.	     * @return The old value.	     * @throws UnsupportedOperationException as setting the value	     *         is not supported.	     */	    public V setValue(V o)	    {	      throw new UnsupportedOperationException();	    }	  };	  entries = singleton(entry);	}      return entries;    }