CombineFnFinalTransform (Nemo Project 0.4 API)

java.lang.Object
- org.apache.nemo.common.ir.vertex.transform.NoWatermarkEmitTransform<org.apache.beam.sdk.util.WindowedValue<org.apache.beam.sdk.values.KV<K,A>>,org.apache.beam.sdk.util.WindowedValue<org.apache.beam.sdk.values.KV<K,O>>>
- - org.apache.nemo.compiler.frontend.beam.transform.CombineFnFinalTransform<K,A,O>

Type Parameters:

K - Key type.

A - Accum type.

O - Output type.

All Implemented Interfaces:

java.io.Serializable, Transform<org.apache.beam.sdk.util.WindowedValue<org.apache.beam.sdk.values.KV<K,A>>,org.apache.beam.sdk.util.WindowedValue<org.apache.beam.sdk.values.KV<K,O>>>
```
public final class CombineFnFinalTransform<K,A,O>
extends NoWatermarkEmitTransform<org.apache.beam.sdk.util.WindowedValue<org.apache.beam.sdk.values.KV<K,A>>,org.apache.beam.sdk.util.WindowedValue<org.apache.beam.sdk.values.KV<K,O>>>
```
Accumulates all of the partially accumulated KVs(Key, Accum) into KVs(Key, Output). (Currently supports batch-style global windows only) TODO #263: Partial Combining for Beam Streaming TODO #264: Partial Combining with Beam SideInputs

See Also:

Serialized Form

Nested Class Summary
- Nested classes/interfaces inherited from interface org.apache.nemo.common.ir.vertex.transform.Transform
  Transform.Context

Constructor Summary

Constructors
Constructor Description

CombineFnFinalTransform(org.apache.beam.sdk.transforms.CombineFnBase.GlobalCombineFn<?,A,O> combineFn)
Constructor.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`close()`	Close the transform.
`void`	`onData(org.apache.beam.sdk.util.WindowedValue<org.apache.beam.sdk.values.KV<K,A>> element)`	On data received.
`void`	`prepare(Transform.Context context, OutputCollector<org.apache.beam.sdk.util.WindowedValue<org.apache.beam.sdk.values.KV<K,O>>> oc)`	Prepare the transform.
`java.lang.String`	`toString()`

Methods inherited from class org.apache.nemo.common.ir.vertex.transform.NoWatermarkEmitTransform
onLatencymark, onWatermark

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

CombineFnFinalTransform

public CombineFnFinalTransform(org.apache.beam.sdk.transforms.CombineFnBase.GlobalCombineFn<?,A,O> combineFn)

Constructor.

Parameters:: combineFn - combine function.

Method Detail
- prepare
```
public void prepare(Transform.Context context,
                    OutputCollector<org.apache.beam.sdk.util.WindowedValue<org.apache.beam.sdk.values.KV<K,O>>> oc)
```
  Description copied from interface: Transform
  
  Prepare the transform.
  
  Parameters:
  
  context - of the transform.
  
  oc - that collects outputs.
- onData
```
public void onData(org.apache.beam.sdk.util.WindowedValue<org.apache.beam.sdk.values.KV<K,A>> element)
```
  Description copied from interface: Transform
  
  On data received.
  
  Parameters:
  
  element - data received.
- close
```
public void close()
```
  Description copied from interface: Transform
  
  Close the transform.
- toString
```
public java.lang.String toString()
```
  Overrides:
  
  toString in class java.lang.Object