public interface StreamTask
MessageCollector. A StreamTask may be augmented by implementing other interfaces, such as
The methods of StreamTasks and associated other tasks are guaranteed to be called in a single-threaded fashion;
no extra synchronization is necessary on the part of the class implementer. References to instances of
TaskCoordinator should not be held onto between calls; there is no guarantee that
these will not be invalidated or otherwise used by the framework.
void process(IncomingMessageEnvelope envelope, MessageCollector collector, TaskCoordinator coordinator) throws java.lang.Exception
envelope- Contains the received deserialized message and key, and also information regarding the stream and partition of which the message was received from.
collector- Contains the means of sending message envelopes to the output stream. The collector must only be used during the current call to the process method; you should not reuse the collector between invocations of this method.
coordinator- Manages execution of tasks.
java.lang.Exception- Any exception types encountered during the execution of the processing task.