ds.granules.streaming.core

Class StreamSource

java.lang.Object

ds.granules.operation.OperationBase

ds.granules.operation.MapReduceBase

ds.granules.streaming.core.StreamBase

ds.granules.streaming.core.StreamSource

All Implemented Interfaces:

ds.funnel.data.format.FormatMarshaller, Map, MapReduce, Operation, OperationConfiguration, Reduce

public abstract class StreamSource
extends StreamBase

This class should be extended to implement a stream source. Stream sources can be considered as entry points for stream computations. Stream sources implements a pull based approach to take data in. A stream source may be integrated with the stream producer or with a message queue.

Author:

: Thilina Buddhika

Nested Class Summary

Nested classes/interfaces inherited from interface ds.granules.operation.Operation

Operation.OperationType

Field Summary

Fields inherited from class ds.granules.streaming.core.StreamBase

identifier, incomingStreamTypes, isBufferingAccess, outGoingStreamTypes, streamDataset

Fields inherited from class ds.granules.operation.MapReduceBase

defaultOutputStream, mapReduceDataset, MODULE

Constructor Summary

Constructors

Constructor and Description
StreamSource()

Method Summary

Methods

Modifier and Type	Method and Description
abstract void	emit() Emit the next tuple.
void	execute() Execute the operation.

Methods inherited from class ds.granules.streaming.core.StreamBase

addStreamConsumer, declareOutputStreams, declareStream, getDatasetIdentifier, getDefaultStreamDataset, getStreamIdentifier, initialize, marshall, unmarshall, writeToStream

Methods inherited from class ds.granules.operation.MapReduceBase

addMap, addMapper, addReduce, addReducer, createResults, getAwaitingOutputsFrom, getDatasetCollection, getMapIdentifiers, getMapReduceDataset, getNumberOfMaps, getNumberOfReducers, getReduceIdentifiers, isAwaitingOutputs, removeMap, removeMapper, removeReduce, removeReducer, resetOutputTracker, setReceivedOutputFrom, writeResults, writeResults, writeResults, writeResults

Methods inherited from class ds.granules.operation.OperationBase

changeToExecuteFixedNumberOfTimes, changeToExecuteOnce, changeToExecutePeriodically, changeToExecuteWhenDataAvailable, changeToStayAlive, dispose, getDomain, getExecutionProfile, getInstanceIdentifier, getOperationIdentifier, getProcessingDirectives, getVersionInformation, hasDatasetCollection, hasExecutionProfile, hasProcessingDirectives, isInitialized, markInitializationAsComplete, needsInitialization, setAsExecuteContinuously, setAsExecuteFixedNumberOfTimes, setAsExecuteOnce, setAsExecutePeriodically, setAsExecuteWhenDataAvailable, setAsStayAlive, setDatasetCollection, setDomain, setInitializationComplete, setInitializationNeeded, setInstanceIdentifier, setOperationIdentifier, setProcessingDirectives, setTeminationConditionReached, setVersionInformation, terminationConditionReached, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface ds.granules.operation.Operation

dispose, getDomain, getExecutionProfile, getInstanceIdentifier, getOperationIdentifier, getProcessingDirectives, getVersionInformation, hasDatasetCollection, hasExecutionProfile, hasProcessingDirectives, isInitialized, needsInitialization, terminationConditionReached, toString

Constructor Detail

StreamSource

public StreamSource()

Method Detail

execute

public void execute()
             throws ProcessingException

Description copied from interface: Operation

Execute the operation.

Specified by:

execute in interface Operation

Specified by:

execute in class OperationBase

Throws:

ProcessingException - If there are problems executing the operation in question.

emit

public abstract void emit()
                   throws StreamingDatasetException

Emit the next tuple.

Throws:

StreamingDatasetException