question: @ Override public boolean contains ( Object key ) { if ( key == null ) return _map . _nullValue != null ; K1 [ ] keys = _map . _keys ; for ( int i = keys . length - 1 ; i >= 0 ; i -- ) { K1 testKey = keys [ i ] ; if ( key . equals ( testKey ) ) return true ; } return false ; }
target:  Returns true if the map contains the value.