org.protempa

Class MultiplexingDataStreamingEventIterator

java.lang.Object

org.protempa.MultiplexingDataStreamingEventIterator

All Implemented Interfaces:

AutoCloseable, DataStreamingEventIterator<Proposition>

Direct Known Subclasses:

DataSourceBackendMultiplexingDataStreamingEventIterator

public class MultiplexingDataStreamingEventIterator
extends Object
implements DataStreamingEventIterator<Proposition>

Iterator-like access to DataStreamingEvents. This implementation groups (multiplexes) propositions retrieved from multiple DataStreamingEventIterators by key id. It assembles all of the propositions for a given key id with the help of a PropositionDataStreamerProcessor. After this assembly has been completed for each key id, the iterator calls the PropositionDataStreamerProcessor's PropositionDataStreamerProcessor.fireKeyCompleted(java.lang.String, java.util.List<org.protempa.proposition.Proposition>) method with the key id and list of propositions. The iterator gets each assembled key id and proposition list from the PropositionDataStreamerProcessor to return to the caller. Subclasses of PropositionDataStreamerProcessor may specify additional processing to be performed on the key id and proposition list prior to returning them to the caller.

Author:

Andrew Post

Method Summary

Modifier and Type	Method and Description
void	close() Calls the underlying DataStreamingEventIterators DataStreamingEventIterator.close() method.
boolean	hasNext() Returns true if the iteration has more DataStreamingEvents.
DataStreamingEvent<Proposition>	next() Returns the next DataStreamingEvent in the iteration.

Methods inherited from class java.lang.Object

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

Method Detail

hasNext

public boolean hasNext()
                throws DataSourceReadException

Description copied from interface: DataStreamingEventIterator

Returns true if the iteration has more DataStreamingEvents. (In other words, returns true if next would return a DataStreamingEvent rather than throwing an exception.)

Specified by:

hasNext in interface DataStreamingEventIterator<Proposition>

Returns:

true if the iterator has more DataStreamingEvents.

Throws:

DataSourceReadException - if an error occurred reading data from the underlying data source.

next

public DataStreamingEvent<Proposition> next()
                                     throws DataSourceReadException

Description copied from interface: DataStreamingEventIterator

Returns the next DataStreamingEvent in the iteration.

Specified by:

next in interface DataStreamingEventIterator<Proposition>

Returns:

the next DataStreamingEvent in the iteration.

Throws:

DataSourceReadException - if an error occurred reading data from the underlying data source.

close

public void close()
           throws DataSourceReadException

Calls the underlying DataStreamingEventIterators DataStreamingEventIterator.close() method.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface DataStreamingEventIterator<Proposition>

Throws:

DataSourceReadException