:return: the StreamingQueryException if the query was terminated by an exception, or None.

def exception(self):
        """
        :return: the StreamingQueryException if the query was terminated by an exception, or None.
        """
        if self._jsq.exception().isDefined():
            je = self._jsq.exception().get()
            msg = je.toString().split(': ', 1)[1]  # Drop the Java StreamingQueryException type info
            stackTrace = '\n\t at '.join(map(lambda x: x.toString(), je.getStackTrace()))
            return StreamingQueryException(msg, stackTrace, je.getCause())
        else:
            return None