public boolean delete(final Txn<T> txn, final T key) {
    return delete(txn, key, null);
  }
public boolean delete ( final Txn < T > txn , final T key ) { return delete ( txn , key , null ) ; }
Deletes the key using the passed transaction.

@param txn transaction handle (not null; not committed; must be R-W)
@param key key to delete from the database (not null)
@return true if the key/data pair was found, false otherwise

@see #delete(org.lmdbjava.Txn, java.lang.Object, java.lang.Object)