org.apache.flink.runtime.state.heap

Class CopyOnWriteSkipListStateMap<K,N,S>

java.lang.Object

org.apache.flink.runtime.state.heap.StateMap<K,N,S>

org.apache.flink.runtime.state.heap.CopyOnWriteSkipListStateMap<K,N,S>

Type Parameters:

K - type of key

N - type of namespace

S - type of state

All Implemented Interfaces:

AutoCloseable, Iterable<StateEntry<K,N,S>>

public final class CopyOnWriteSkipListStateMap<K,N,S>
extends StateMap<K,N,S>
implements AutoCloseable

Implementation of state map which is based on skip list with copy-on-write support. states will be serialized to bytes and stored in the space allocated with the given allocator.

Constructor Summary

Constructors

Constructor and Description
CopyOnWriteSkipListStateMap(TypeSerializer<K> keySerializer, TypeSerializer<N> namespaceSerializer, TypeSerializer<S> stateSerializer, Allocator spaceAllocator, int numKeysToDeleteOneTime, float logicalRemovedKeysRatio)

Method Summary

Modifier and Type	Method and Description
void	close()
boolean	containsKey(K key, N namespace) Returns whether this map contains the specified key/namespace composite key.
S	get(K key, N namespace) Returns the state for the composite of active key and given namespace.
Stream<K>	getKeys(N namespace)
int	getRequestCount()
InternalKvState.StateIncrementalVisitor<K,N,S>	getStateIncrementalVisitor(int recommendedMaxNumberOfReturnedRecords)
Iterator<StateEntry<K,N,S>>	iterator()
void	put(K key, N namespace, S state) Maps the specified key/namespace composite key to the specified value.
S	putAndGetOld(K key, N namespace, S state) Maps the composite of active key and given namespace to the specified state.
void	releaseSnapshot(StateMapSnapshot<K,N,S,? extends StateMap<K,N,S>> snapshotToRelease) Releases a snapshot for this StateMap.
void	remove(K key, N namespace) Removes the mapping for the composite of active key and given namespace.
S	removeAndGetOld(K key, N namespace) Removes the mapping for the composite of active key and given namespace, returning the state that was found under the entry.
int	size() Returns the total number of entries in this StateMap.
int	sizeOfNamespace(Object namespace)
CopyOnWriteSkipListStateMapSnapshot<K,N,S>	stateSnapshot() Creates a snapshot of this StateMap, to be written in checkpointing.
<T> void	transform(K key, N namespace, T value, StateTransformationFunction<S,T> transformation) Applies the given StateTransformationFunction to the state (1st input argument), using the given value as second input argument.

Methods inherited from class org.apache.flink.runtime.state.heap.StateMap

isEmpty

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Constructor Detail

CopyOnWriteSkipListStateMap

public CopyOnWriteSkipListStateMap(@Nonnull
                                   TypeSerializer<K> keySerializer,
                                   @Nonnull
                                   TypeSerializer<N> namespaceSerializer,
                                   @Nonnull
                                   TypeSerializer<S> stateSerializer,
                                   @Nonnull
                                   Allocator spaceAllocator,
                                   int numKeysToDeleteOneTime,
                                   float logicalRemovedKeysRatio)

Method Detail

size

public int size()

Description copied from class: StateMap

Returns the total number of entries in this StateMap.

Specified by:

size in class StateMap<K,N,S>

Returns:

the number of entries in this StateMap.

getRequestCount

public int getRequestCount()

get

public S get(K key,
             N namespace)

Description copied from class: StateMap

Returns the state for the composite of active key and given namespace.

Specified by:

get in class StateMap<K,N,S>

Parameters:

key - the key. Not null.

namespace - the namespace. Not null.

Returns:

the state of the mapping with the specified key/namespace composite key, or null if no mapping for the specified key is found.

containsKey

public boolean containsKey(K key,
                           N namespace)

Description copied from class: StateMap

Returns whether this map contains the specified key/namespace composite key.

Specified by:

containsKey in class StateMap<K,N,S>

Parameters:

key - the key in the composite key to search for. Not null.

namespace - the namespace in the composite key to search for. Not null.

Returns:

true if this map contains the specified key/namespace composite key, false otherwise.

put

public void put(K key,
                N namespace,
                S state)

Description copied from class: StateMap

Maps the specified key/namespace composite key to the specified value. This method should be preferred over #putAndGetOld(K, N, S) (key, Namespace, State) when the caller is not interested in the old state.

Specified by:

put in class StateMap<K,N,S>

Parameters:

key - the key. Not null.

namespace - the namespace. Not null.

state - the state. Can be null.

putAndGetOld

public S putAndGetOld(K key,
                      N namespace,
                      S state)

Description copied from class: StateMap

Maps the composite of active key and given namespace to the specified state. Returns the previous state that was registered under the composite key.

Specified by:

putAndGetOld in class StateMap<K,N,S>

Parameters:

key - the key. Not null.

namespace - the namespace. Not null.

state - the state. Can be null.

Returns:

the state of any previous mapping with the specified key or null if there was no such mapping.

remove

public void remove(K key,
                   N namespace)

Description copied from class: StateMap

Removes the mapping for the composite of active key and given namespace. This method should be preferred over #removeAndGetOld(K, N) when the caller is not interested in the old state.

Specified by:

remove in class StateMap<K,N,S>

Parameters:

key - the key of the mapping to remove. Not null.

namespace - the namespace of the mapping to remove. Not null.

removeAndGetOld

public S removeAndGetOld(K key,
                         N namespace)

Description copied from class: StateMap

Removes the mapping for the composite of active key and given namespace, returning the state that was found under the entry.

Specified by:

removeAndGetOld in class StateMap<K,N,S>

Parameters:

key - the key of the mapping to remove. Not null.

namespace - the namespace of the mapping to remove. Not null.

Returns:

the state of the removed mapping or null if no mapping for the specified key was found.

transform

public <T> void transform(K key,
                          N namespace,
                          T value,
                          StateTransformationFunction<S,T> transformation)
                   throws Exception

Description copied from class: StateMap

Applies the given StateTransformationFunction to the state (1st input argument), using the given value as second input argument. The result of StateTransformationFunction.apply(Object, Object) is then stored as the new state. This function is basically an optimization for get-update-put pattern.

Specified by:

transform in class StateMap<K,N,S>

Parameters:

key - the key. Not null.

namespace - the namespace. Not null.

value - the value to use in transforming the state. Can be null.

transformation - the transformation function.

Throws:

Exception - if some exception happens in the transformation function.

getKeys

public Stream<K> getKeys(N namespace)

Specified by:

getKeys in class StateMap<K,N,S>

sizeOfNamespace

public int sizeOfNamespace(Object namespace)

Specified by:

sizeOfNamespace in class StateMap<K,N,S>

iterator

@Nonnull
public Iterator<StateEntry<K,N,S>> iterator()

Specified by:

iterator in interface Iterable<StateEntry<K,N,S>>

getStateIncrementalVisitor

public InternalKvState.StateIncrementalVisitor<K,N,S> getStateIncrementalVisitor(int recommendedMaxNumberOfReturnedRecords)

Specified by:

getStateIncrementalVisitor in class StateMap<K,N,S>

stateSnapshot

@Nonnull
public CopyOnWriteSkipListStateMapSnapshot<K,N,S> stateSnapshot()

Description copied from class: StateMap

Creates a snapshot of this StateMap, to be written in checkpointing. Users should call StateMap.releaseSnapshot(StateMapSnapshot) after using the returned object.

Specified by:

stateSnapshot in class StateMap<K,N,S>

Returns:

a snapshot from this StateMap, for checkpointing.

releaseSnapshot

public void releaseSnapshot(StateMapSnapshot<K,N,S,? extends StateMap<K,N,S>> snapshotToRelease)

Description copied from class: StateMap

Releases a snapshot for this StateMap. This method should be called once a snapshot is no more needed.

Overrides:

releaseSnapshot in class StateMap<K,N,S>

Parameters:

snapshotToRelease - the snapshot to release, which was previously created by this state map.

close

public void close()

Specified by:

close in interface AutoCloseable