public static KeySet singleKey(Key key) {
    return new KeySet(false, ImmutableList.of(key), ImmutableList.<KeyRange>of());
  }
public static KeySet singleKey ( Key key ) { return new KeySet ( false , ImmutableList . of ( key ) , ImmutableList . < KeyRange > of ( ) ) ; }
Creates a key set containing a single key. {@code key} should contain exactly as many elements
as there are columns in the primary or index key with this this key set is used.