org.apache.flink.streaming.api.operators

Interface StreamOperator<OUT>

Type Parameters:

OUT - The output type of the operator

All Superinterfaces:

Serializable

All Known Subinterfaces:

OneInputStreamOperator<IN,OUT>, StatefulStreamOperator<OUT>, TwoInputStreamOperator<IN1,IN2,OUT>

All Known Implementing Classes:

AbstractStreamOperator, AbstractUdfStreamOperator, CoStreamFlatMap, CoStreamGroupedReduce, CoStreamMap, CoStreamReduce, CoStreamWindow, GroupedActiveDiscretizer, GroupedStreamDiscretizer, GroupedWindowBuffer, ParallelMergeOperator, StreamCounter, StreamDiscretizer, StreamFilter, StreamFlatMap, StreamFold, StreamGroupedFold, StreamGroupedReduce, StreamMap, StreamProject, StreamReduce, StreamSink, StreamSource, StreamWindowBuffer, WindowFlattener, WindowFolder, WindowMapper, WindowMerger, WindowPartitioner, WindowReducer

public interface StreamOperator<OUT>
extends Serializable

Basic interface for stream operators. Implementers would implement one of OneInputStreamOperator or TwoInputStreamOperator to create operators that process elements. You can use AbstractStreamOperator as a base class for custom operators.

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	StreamOperator.ChainingStrategy Defines the chaining scheme for the operator.

Method Summary

Modifier and Type	Method and Description
void	close() This method is called after no more elements for can arrive for processing.
StreamOperator.ChainingStrategy	getChainingStrategy()
boolean	isInputCopyingDisabled() An operator can return true here to disable copying of its input elements.
void	open(org.apache.flink.configuration.Configuration config) This method is called before any elements are processed.
void	setChainingStrategy(StreamOperator.ChainingStrategy strategy)
void	setup(Output<OUT> output, org.apache.flink.api.common.functions.RuntimeContext runtimeContext) Initializes the StreamOperator for input and output handling.

Method Detail

setup

void setup(Output<OUT> output,
           org.apache.flink.api.common.functions.RuntimeContext runtimeContext)

Initializes the StreamOperator for input and output handling.

open

void open(org.apache.flink.configuration.Configuration config)
   throws Exception

This method is called before any elements are processed.

Throws:

Exception

close

void close()
    throws Exception

This method is called after no more elements for can arrive for processing.

Throws:

Exception

isInputCopyingDisabled

boolean isInputCopyingDisabled()

An operator can return true here to disable copying of its input elements. This overrides the object-reuse setting on the ExecutionConfig

setChainingStrategy

void setChainingStrategy(StreamOperator.ChainingStrategy strategy)

getChainingStrategy

StreamOperator.ChainingStrategy getChainingStrategy()