org.apache.beam.sdk.transforms

Class IntraBundleParallelization.MultiThreadedIntraBundleProcessingDoFn<InputT,OutputT>

java.lang.Object

org.apache.beam.sdk.transforms.DoFn<InputT,OutputT>

org.apache.beam.sdk.transforms.IntraBundleParallelization.MultiThreadedIntraBundleProcessingDoFn<InputT,OutputT>

Type Parameters:

InputT - the type of the (main) input elements

OutputT - the type of the (main) output elements

All Implemented Interfaces:

Serializable, HasDisplayData

Enclosing class:

IntraBundleParallelization

public static class IntraBundleParallelization.MultiThreadedIntraBundleProcessingDoFn<InputT,OutputT>
extends DoFn<InputT,OutputT>

A multi-threaded DoFn wrapper.

See Also:

IntraBundleParallelization.of(DoFn), Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.beam.sdk.transforms.DoFn

DoFn.Context, DoFn.ProcessContext, DoFn.RequiresWindowAccess

Constructor Summary

Constructors

Constructor and Description
MultiThreadedIntraBundleProcessingDoFn(DoFn<InputT,OutputT> doFn, int maxParallelism)

Method Summary

Modifier and Type	Method and Description
void	finishBundle(DoFn.Context c) Finishes processing this batch of elements.
protected TypeDescriptor<InputT>	getInputTypeDescriptor() Returns a TypeDescriptor capturing what is known statically about the input type of this DoFn instance's most-derived class.
protected TypeDescriptor<OutputT>	getOutputTypeDescriptor() Returns a TypeDescriptor capturing what is known statically about the output type of this DoFn instance's most-derived class.
void	processElement(DoFn.ProcessContext c) Processes one input element.
void	startBundle(DoFn.Context c) Prepares this DoFn instance for processing a batch of elements.

Methods inherited from class org.apache.beam.sdk.transforms.DoFn

createAggregator, createAggregator, getAllowedTimestampSkew, populateDisplayData

Methods inherited from class java.lang.Object

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

Constructor Detail

MultiThreadedIntraBundleProcessingDoFn

public MultiThreadedIntraBundleProcessingDoFn(DoFn<InputT,OutputT> doFn,
                                              int maxParallelism)

Method Detail

startBundle

public void startBundle(DoFn.Context c)
                 throws Exception

Description copied from class: DoFn

Prepares this DoFn instance for processing a batch of elements.

By default, does nothing.

Overrides:

startBundle in class DoFn<InputT,OutputT>

Throws:

Exception

processElement

public void processElement(DoFn.ProcessContext c)
                    throws Exception

Description copied from class: DoFn

Processes one input element.

The current element of the input PCollection is returned by c.element(). It should be considered immutable. The Dataflow runtime will not mutate the element, so it is safe to cache, etc. The element should not be mutated by any of the DoFn methods, because it may be cached elsewhere, retained by the Dataflow runtime, or used in other unspecified ways.

A value is added to the main output PCollection by DoFn.Context.output(OutputT). Once passed to output the element should be considered immutable and not be modified in any way. It may be cached elsewhere, retained by the Dataflow runtime, or used in other unspecified ways.

Specified by:

processElement in class DoFn<InputT,OutputT>

Throws:

Exception

See Also:

DoFn.ProcessContext

finishBundle

public void finishBundle(DoFn.Context c)
                  throws Exception

Description copied from class: DoFn

Finishes processing this batch of elements.

By default, does nothing.

Overrides:

finishBundle in class DoFn<InputT,OutputT>

Throws:

Exception

getInputTypeDescriptor

protected TypeDescriptor<InputT> getInputTypeDescriptor()

Description copied from class: DoFn

Returns a TypeDescriptor capturing what is known statically about the input type of this DoFn instance's most-derived class.

See DoFn.getOutputTypeDescriptor() for more discussion.

Overrides:

getInputTypeDescriptor in class DoFn<InputT,OutputT>

getOutputTypeDescriptor

protected TypeDescriptor<OutputT> getOutputTypeDescriptor()

Description copied from class: DoFn

Returns a TypeDescriptor capturing what is known statically about the output type of this DoFn instance's most-derived class.

In the normal case of a concrete DoFn subclass with no generic type parameters of its own (including anonymous inner classes), this will be a complete non-generic type, which is good for choosing a default output Coder<OutputT> for the output PCollection<OutputT>.

Overrides:

getOutputTypeDescriptor in class DoFn<InputT,OutputT>