org.apache.flink.streaming.api.transformations

Class SelectTransformation<T>

java.lang.Object

org.apache.flink.streaming.api.transformations.StreamTransformation<T>

org.apache.flink.streaming.api.transformations.SelectTransformation<T>

Type Parameters:

T - The type of the elements that result from this SelectTransformation

@Internal
public class SelectTransformation<T>
extends StreamTransformation<T>

This transformation represents a selection of only certain upstream elements. This must follow a SplitTransformation that splits elements into several logical streams with assigned names.

This does not create a physical operation, it only affects how upstream operations are connected to downstream operations.

Field Summary

Fields inherited from class org.apache.flink.streaming.api.transformations.StreamTransformation

bufferTimeout, id, idCounter, name, outputType, typeUsed

Constructor Summary

Constructors

Constructor and Description
SelectTransformation(StreamTransformation<T> input, List<String> selectedNames) Creates a new SelectionTransformation from the given input that only selects the streams with the selected names.

Method Summary

Modifier and Type	Method and Description
StreamTransformation<T>	getInput() Returns the input StreamTransformation.
List<String>	getSelectedNames() Returns the names of the split streams that this SelectTransformation selects.
Collection<StreamTransformation<?>>	getTransitivePredecessors() Returns all transitive predecessor StreamTransformations of this StreamTransformation.
void	setChainingStrategy(ChainingStrategy strategy) Sets the chaining strategy of this StreamTransformation.

Methods inherited from class org.apache.flink.streaming.api.transformations.StreamTransformation

equals, getBufferTimeout, getId, getMaxParallelism, getMinResources, getName, getNewNodeId, getOutputType, getParallelism, getPreferredResources, getSlotSharingGroup, getUid, getUserProvidedNodeHash, hashCode, setBufferTimeout, setMaxParallelism, setName, setOutputType, setParallelism, setResources, setSlotSharingGroup, setUid, setUidHash, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

SelectTransformation

public SelectTransformation(StreamTransformation<T> input,
                            List<String> selectedNames)

Creates a new SelectionTransformation from the given input that only selects the streams with the selected names.

Parameters:

input - The input StreamTransformation

selectedNames - The names from the upstream SplitTransformation that this SelectTransformation selects.

Method Detail

getInput

public StreamTransformation<T> getInput()

Returns the input StreamTransformation.

getSelectedNames

public List<String> getSelectedNames()

Returns the names of the split streams that this SelectTransformation selects.

getTransitivePredecessors

public Collection<StreamTransformation<?>> getTransitivePredecessors()

Description copied from class: StreamTransformation

Returns all transitive predecessor StreamTransformations of this StreamTransformation. This is, for example, used when determining whether a feedback edge of an iteration actually has the iteration head as a predecessor.

Specified by:

getTransitivePredecessors in class StreamTransformation<T>

Returns:

The list of transitive predecessors.

setChainingStrategy

public final void setChainingStrategy(ChainingStrategy strategy)

Description copied from class: StreamTransformation

Sets the chaining strategy of this StreamTransformation.

Specified by:

setChainingStrategy in class StreamTransformation<T>