org.apache.flink.runtime.state.internal

Interface InternalKvState<N>

Type Parameters:

N - The type of the namespace.

All Superinterfaces:

State

All Known Subinterfaces:

InternalAggregatingState<N,IN,OUT>, InternalAppendingState<N,IN,OUT>, InternalFoldingState<N,T,ACC>, InternalListState<N,T>, InternalMapState<N,UK,UV>, InternalMergingState<N,IN,OUT>, InternalReducingState<N,T>, InternalValueState<N,T>

All Known Implementing Classes:

AbstractHeapMergingState, AbstractHeapState, HeapAggregatingState, HeapFoldingState, HeapListState, HeapMapState, HeapReducingState, HeapValueState

public interface InternalKvState<N>
extends State

The InternalKvState is the root of the internal state type hierarchy, similar to the State being the root of the public API state hierarchy.

The internal state classes give access to the namespace getters and setters and access to additional functionality, like raw value access or state merging.

The public API state hierarchy is intended to be programmed against by Flink applications. The internal state hierarchy holds all the auxiliary methods that are used by the runtime and not intended to be used by user applications. These internal methods are considered of limited use to users and only confusing, and are usually not regarded as stable across releases.

Each specific type in the internal state hierarchy extends the type from the public state hierarchy:

             State
               |
               +-------------------InternalKvState
               |                         |
          MergingState                   |
               |                         |
               +-----------------InternalMergingState
               |                         |
      +--------+------+                  |
      |               |                  |
 ReducingState    ListState        +-----+-----------------+
      |               |            |                       |
      +-----------+   +-----------   -----------------InternalListState
                  |                |
                  +---------InternalReducingState
 

Method Summary

Methods

Modifier and Type	Method and Description
byte[]	getSerializedValue(byte[] serializedKeyAndNamespace) Returns the serialized value for the given key and namespace.
void	setCurrentNamespace(N namespace) Sets the current namespace, which will be used when using the state access methods.

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

clear

Method Detail

setCurrentNamespace

void setCurrentNamespace(N namespace)

Sets the current namespace, which will be used when using the state access methods.

Parameters:

namespace - The namespace.

getSerializedValue

byte[] getSerializedValue(byte[] serializedKeyAndNamespace)
                          throws Exception

Returns the serialized value for the given key and namespace.

If no value is associated with key and namespace, null is returned.

Parameters:

serializedKeyAndNamespace - Serialized key and namespace

Returns:

Serialized value or null if no value is associated with the key and namespace.

Throws:

Exception - Exceptions during serialization are forwarded