org.apache.flink.runtime.state.internal

Interface InternalMergingState<N,IN,OUT>

Type Parameters:

N - The type of the namespace

IN - The type of elements added to the state

OUT - The type of elements

All Superinterfaces:

AppendingState<IN,OUT>, InternalAppendingState<N,IN,OUT>, InternalKvState<N>, MergingState<IN,OUT>, State

All Known Subinterfaces:

InternalAggregatingState<N,IN,OUT>, InternalListState<N,T>, InternalReducingState<N,T>

All Known Implementing Classes:

AbstractHeapMergingState, HeapAggregatingState, HeapListState, HeapReducingState

public interface InternalMergingState<N,IN,OUT>
extends InternalAppendingState<N,IN,OUT>, MergingState<IN,OUT>

The peer to the MergingState in the internal state type hierarchy. See InternalKvState for a description of the internal state hierarchy.

Method Summary

Methods

Modifier and Type	Method and Description
void	mergeNamespaces(N target, Collection<N> sources) Merges the state of the current key for the given source namespaces into the state of the target namespace.

Methods inherited from interface org.apache.flink.runtime.state.internal.InternalKvState

getSerializedValue, setCurrentNamespace

Methods inherited from interface org.apache.flink.api.common.state.AppendingState

add, get

Methods inherited from interface org.apache.flink.api.common.state.State

clear

Method Detail

mergeNamespaces

void mergeNamespaces(N target,
                   Collection<N> sources)
                     throws Exception

Merges the state of the current key for the given source namespaces into the state of the target namespace.

Parameters:

target - The target namespace where the merged state should be stored.

sources - The source namespaces whose state should be merged.

Throws:

Exception - The method may forward exception thrown internally (by I/O or functions).