CombineWithContext.CombineFnWithContext

java.lang.Object
- org.apache.beam.sdk.transforms.CombineWithContext.CombineFnWithContext<InputT,AccumT,OutputT>

All Implemented Interfaces:

java.io.Serializable, CombineFnBase.GlobalCombineFn<InputT,AccumT,OutputT>, CombineWithContext.RequiresContextInternal, HasDisplayData

Direct Known Subclasses:

CombineFns.ComposedCombineFnWithContext

Enclosing class:

CombineWithContext
```
public abstract static class CombineWithContext.CombineFnWithContext<InputT,AccumT,OutputT>
extends java.lang.Object
implements CombineWithContext.RequiresContextInternal
```
A combine function that has access to PipelineOptions and side inputs through CombineWithContext.Context.
See the equivalent Combine.CombineFn for details about combine functions.

See Also:

Serialized Form

Constructor Summary

Constructors
Constructor and Description

CombineFnWithContext()

Constructors
Constructor and Description
`CombineFnWithContext()`

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`abstract AccumT`	`addInput(AccumT accumulator, InputT input, CombineWithContext.Context c)` Adds the given input value to the given accumulator, returning the new accumulator value.
`OutputT`	`apply(java.lang.Iterable<? extends InputT> inputs, CombineWithContext.Context c)` Applies this `CombineFnWithContext` to a collection of input values to produce a combined output value.
`AccumT`	`compact(AccumT accumulator, CombineWithContext.Context c)` Returns an accumulator that represents the same logical value as the input accumulator, but may have a more compact representation.
`abstract AccumT`	`createAccumulator(CombineWithContext.Context c)` Returns a new, mutable accumulator value, representing the accumulation of zero input values.
`OutputT`	`defaultValue()` Returns the default value when there are no values added to the accumulator.
`abstract OutputT`	`extractOutput(AccumT accumulator, CombineWithContext.Context c)` Returns the output value that is the result of combining all the input values represented by the given accumulator.
`java.lang.reflect.TypeVariable<?>`	`getAccumTVariable()` Returns the `TypeVariable` of `AccumT`.
`Coder<AccumT>`	`getAccumulatorCoder(CoderRegistry registry, Coder<InputT> inputCoder)` Returns the `Coder` to use for accumulator `AccumT` values, or null if it is not able to be inferred.
`Coder<OutputT>`	`getDefaultOutputCoder(CoderRegistry registry, Coder<InputT> inputCoder)` Returns the `Coder` to use by default for output `OutputT` values, or null if it is not able to be inferred.
`java.lang.String`	`getIncompatibleGlobalWindowErrorMessage()` Returns the error message for not supported default values in Combine.globally().
`java.lang.reflect.TypeVariable<?>`	`getInputTVariable()` Returns the `TypeVariable` of `InputT`.
`java.lang.reflect.TypeVariable<?>`	`getOutputTVariable()` Returns the `TypeVariable` of `OutputT`.
`abstract AccumT`	`mergeAccumulators(java.lang.Iterable<AccumT> accumulators, CombineWithContext.Context c)` Returns an accumulator representing the accumulation of all the input values accumulated in the merging accumulators.
`void`	`populateDisplayData(DisplayData.Builder builder)` Register display data for the given transform or component.

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

- Constructor Detail
  - CombineFnWithContext
```
public CombineFnWithContext()
```
- Method Detail
  - createAccumulator
```
public abstract AccumT createAccumulator(CombineWithContext.Context c)
```
    Returns a new, mutable accumulator value, representing the accumulation of zero input values.
    It is equivalent to Combine.CombineFn.createAccumulator(), but it has additional access to CombineWithContext.Context.
  - addInput
```
public abstract AccumT addInput(AccumT accumulator,
                                InputT input,
                                CombineWithContext.Context c)
```
    Adds the given input value to the given accumulator, returning the new accumulator value.
    It is equivalent to Combine.CombineFn.addInput(AccumT, InputT), but it has additional access to CombineWithContext.Context.
  - mergeAccumulators
```
public abstract AccumT mergeAccumulators(java.lang.Iterable<AccumT> accumulators,
                                         CombineWithContext.Context c)
```
    Returns an accumulator representing the accumulation of all the input values accumulated in the merging accumulators.
    It is equivalent to Combine.CombineFn.mergeAccumulators(java.lang.Iterable<AccumT>), but it has additional access to CombineWithContext.Context.
  - extractOutput
```
public abstract OutputT extractOutput(AccumT accumulator,
                                      CombineWithContext.Context c)
```
    Returns the output value that is the result of combining all the input values represented by the given accumulator.
    It is equivalent to Combine.CombineFn.extractOutput(AccumT), but it has additional access to CombineWithContext.Context.
  - compact
```
public AccumT compact(AccumT accumulator,
                      CombineWithContext.Context c)
```
    Returns an accumulator that represents the same logical value as the input accumulator, but may have a more compact representation.
    It is equivalent to Combine.CombineFn.compact(AccumT), but it has additional access to CombineWithContext.Context.
  - apply
```
public OutputT apply(java.lang.Iterable<? extends InputT> inputs,
                     CombineWithContext.Context c)
```
    Applies this CombineFnWithContext to a collection of input values to produce a combined output value.
  - defaultValue
```
public OutputT defaultValue()
```
    Description copied from interface: CombineFnBase.GlobalCombineFn
    
    Returns the default value when there are no values added to the accumulator.
    
    Specified by:
    
    defaultValue in interface CombineFnBase.GlobalCombineFn<InputT,AccumT,OutputT>
  - getAccumulatorCoder
```
public Coder<AccumT> getAccumulatorCoder(CoderRegistry registry,
                                         Coder<InputT> inputCoder)
                                  throws CannotProvideCoderException
```
    Description copied from interface: CombineFnBase.GlobalCombineFn
    
    Returns the Coder to use for accumulator AccumT values, or null if it is not able to be inferred.
    By default, uses the knowledge of the Coder being used for InputT values and the enclosing Pipeline's CoderRegistry to try to infer the Coder for AccumT values.
    This is the Coder used to send data through a communication-intensive shuffle step, so a compact and efficient representation may have significant performance benefits.
    
    Specified by:
    
    getAccumulatorCoder in interface CombineFnBase.GlobalCombineFn<InputT,AccumT,OutputT>
    
    Throws:
    
    CannotProvideCoderException
  - getDefaultOutputCoder
```
public Coder<OutputT> getDefaultOutputCoder(CoderRegistry registry,
                                            Coder<InputT> inputCoder)
                                     throws CannotProvideCoderException
```
    Description copied from interface: CombineFnBase.GlobalCombineFn
    
    Returns the Coder to use by default for output OutputT values, or null if it is not able to be inferred.
    By default, uses the knowledge of the Coder being used for input InputT values and the enclosing Pipeline's CoderRegistry to try to infer the Coder for OutputT values.
    
    Specified by:
    
    getDefaultOutputCoder in interface CombineFnBase.GlobalCombineFn<InputT,AccumT,OutputT>
    
    Throws:
    
    CannotProvideCoderException
  - getIncompatibleGlobalWindowErrorMessage
```
public java.lang.String getIncompatibleGlobalWindowErrorMessage()
```
    Description copied from interface: CombineFnBase.GlobalCombineFn
    
    Returns the error message for not supported default values in Combine.globally().
    
    Specified by:
    
    getIncompatibleGlobalWindowErrorMessage in interface CombineFnBase.GlobalCombineFn<InputT,AccumT,OutputT>
  - getInputTVariable
```
public java.lang.reflect.TypeVariable<?> getInputTVariable()
```
    Returns the TypeVariable of InputT.
  - getAccumTVariable
```
public java.lang.reflect.TypeVariable<?> getAccumTVariable()
```
    Returns the TypeVariable of AccumT.
  - getOutputTVariable
```
public java.lang.reflect.TypeVariable<?> getOutputTVariable()
```
    Returns the TypeVariable of OutputT.
  - populateDisplayData
```
public void populateDisplayData(DisplayData.Builder builder)
```
    Register display data for the given transform or component.
    populateDisplayData(DisplayData.Builder) is invoked by Pipeline runners to collect display data via DisplayData.from(HasDisplayData). Implementations may call super.populateDisplayData(builder) in order to register display data in the current namespace, but should otherwise use subcomponent.populateDisplayData(builder) to use the namespace of the subcomponent.
    By default, does not register any display data. Implementors may override this method to provide their own display data.
    
    Specified by:
    
    populateDisplayData in interface HasDisplayData
    
    Parameters:
    
    builder - The builder to populate with display data.
    
    See Also:
    
    HasDisplayData

Class CombineWithContext.CombineFnWithContext<InputT,AccumT,OutputT>

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

CombineFnWithContext

Method Detail

createAccumulator

addInput

mergeAccumulators

extractOutput

compact

apply

defaultValue

getAccumulatorCoder

getDefaultOutputCoder

getIncompatibleGlobalWindowErrorMessage

getInputTVariable

getAccumTVariable

getOutputTVariable

populateDisplayData