Clears component state.

        :param correlation_id: (optional) transaction id to trace execution through call chain.

def clear(self, correlation_id):
        """
        Clears component state.

        :param correlation_id: (optional) transaction id to trace execution through call chain.
        """
        self._lock.acquire()
        try:
            self._cache = {}
        finally:
            self._lock.release()