/** @see org.mulgara.store.tuples.AbstractTuples#next() */
  @Override
  public boolean next() throws TuplesException {
    try {
      currentRow = source.getTriple();
    } catch (TuplesException ex) {
      source.terminate();
      throw ex;
    }
    assert currentRow != null;

    if (currentRow == StatementParser.TERMINATOR) rowCount = source.getStatementCount();
    return currentRow != StatementParser.TERMINATOR;
  }
 /** @see org.mulgara.store.tuples.AbstractTuples#close() */
 @Override
 public void close() throws TuplesException {
   source.terminate();
 }