if (_metaData.getColumnCount() <= fieldOffset || fieldOffset < 0)
if (_metaData.getColumnCount() <= fieldOffset || fieldOffset < 0) { env.invalidArgument("field", fieldOffset);
  public Value getFieldLength(int fieldOffset)  {    try {      if (_metaData == null)        _metaData = _rs.getMetaData();      if (_metaData.getColumnCount() <= fieldOffset || fieldOffset < 0)        return BooleanValue.FALSE;      else        return new LongValue((long) _metaData.getPrecision(fieldOffset + 1));    } catch (SQLException e) {      log.log(Level.FINE, e.toString(), e);      return BooleanValue.FALSE;    }  }