org.apache.fluo.recipes.core.combine

Interface Combiner<K,V>

All Known Implementing Classes:

SummingCombiner

Functional Interface:

This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@FunctionalInterface
public interface Combiner<K,V>

This class was created as an alternative to Combiner. It supports easy and efficient use of java streams when implementing combiners using lambdas.

Since:

1.1.0

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static interface	Combiner.Input<KI,VI>

Method Summary

Modifier and Type	Method and Description
Optional<V>	combine(Combiner.Input<K,V> input) This function is called to combine the current value of a key with updates that were queued for the key.

Method Detail

combine

Optional<V> combine(Combiner.Input<K,V> input)

This function is called to combine the current value of a key with updates that were queued for the key. See the collision free map project level documentation for more information.

Returns:

Then new value for the key. Returning Optional.empty() will cause the key to be deleted.