org.apache.nifi.io.nio.consumer

Interface StreamConsumer

All Known Implementing Classes:

AbstractStreamConsumer

public interface StreamConsumer

A StreamConsumer must be thread safe. It may be accessed concurrently by a thread providing data to process and another thread that is processing that data.

Method Summary

Modifier and Type	Method and Description
void	addFilledBuffer(ByteBuffer buffer) Will be called by the thread that produces byte buffers with available data to be processed.
String	getId() Uniquely identifies the consumer
boolean	isConsumerFinished() If true signals the consumer is done consuming data and will not process any more buffers.
void	process() Will be called by the thread that executes the consumption of data.
void	setReturnBufferQueue(BufferPool returnQueue) Will be called once just after construction.
void	signalEndOfStream() Called once the end of the input stream is detected

Method Detail

setReturnBufferQueue

void setReturnBufferQueue(BufferPool returnQueue)

Will be called once just after construction. It provides the queue to which processed and emptied and cleared buffers must be returned. For each time addFilledBuffer is called there should be an associated add to this given queue. If not, buffers will run out and all stream processing will halt. READ THIS!!!

Parameters:

returnQueue - pool of buffers to use

addFilledBuffer

void addFilledBuffer(ByteBuffer buffer)

Will be called by the thread that produces byte buffers with available data to be processed. If the consumer is finished this should simply return the given buffer to the return buffer queue (after it is cleared)

Parameters:

buffer - filled buffer

process

void process()
      throws IOException

Will be called by the thread that executes the consumption of data. May be called many times though once isConsumerFinished returns true this method will likely do nothing.

Throws:

IOException - if there is an issue processing

signalEndOfStream

void signalEndOfStream()

Called once the end of the input stream is detected

isConsumerFinished

boolean isConsumerFinished()

If true signals the consumer is done consuming data and will not process any more buffers.

Returns:

true if finished

getId

String getId()

Uniquely identifies the consumer

Returns:

identifier of consumer