AggregateFunctionFactory (Eclipse RDF4J 4.2.4)

All Known Implementing Classes:

PopulationStandardDeviationAggregateFactory, PopulationVarianceAggregateFactory, StandardDeviationAggregateFactory, VarianceAggregateFactory
```
@Experimental
public interface AggregateFunctionFactory
```
Factory for a registered AggregateFunction that is evaluated in the same fashion as standard aggregate functions e.g.Sum & Count

Author:

Tomas Kovachev t.kovachev1996@gmail.com

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`AggregateFunction`	`buildFunction(Function<BindingSet,Value> evaluationStep)`	Builds an aggregate function with input evaluation step
`AggregateCollector`	`getCollector()`
`String`	`getIri()`

- Method Detail
  - getIri
```
String getIri()
```
    Returns:
    
    the identifier associated with given function
  - buildFunction
```
AggregateFunction buildFunction(Function<BindingSet,Value> evaluationStep)
```
    Builds an aggregate function with input evaluation step
    
    Parameters:
    
    evaluationStep - used to process values from an iterator's binding set
    
    Returns:
    
    an aggregate function evaluator
  - getCollector
```
AggregateCollector getCollector()
```
    Returns:
    
    result collector associated with given function type