org.apache.flink.runtime.state

Class DefaultOperatorStateBackend

java.lang.Object

org.apache.flink.runtime.state.DefaultOperatorStateBackend

All Implemented Interfaces:

Closeable, AutoCloseable, OperatorStateStore, OperatorStateBackend, Snapshotable<OperatorStateHandle>

@Internal
public class DefaultOperatorStateBackend
extends Object
implements OperatorStateBackend

Default implementation of OperatorStateStore that provides the ability to make snapshots.

Field Summary

Fields

Modifier and Type	Field and Description
static String	DEFAULT_OPERATOR_STATE_NAME The default namespace for state in cases where no state name is provided

Constructor Summary

Constructors

Constructor and Description
DefaultOperatorStateBackend(ClassLoader userClassLoader)

Method Summary

Methods

Modifier and Type	Method and Description
void	close()
void	dispose() Disposes the backend and releases all resources.
<S> ListState<S>	getBroadcastOperatorState(ListStateDescriptor<S> stateDescriptor)
<T extends Serializable> ListState<T>	getBroadcastSerializableListState(String stateName)
<S> ListState<S>	getOperatorState(ListStateDescriptor<S> stateDescriptor)
Set<String>	getRegisteredStateNames()
<T extends Serializable> ListState<T>	getSerializableListState(String stateName)
void	restore(Collection<OperatorStateHandle> restoreSnapshots) Restores state that was previously snapshotted from the provided parameters.
RunnableFuture<OperatorStateHandle>	snapshot(long checkpointId, long timestamp, CheckpointStreamFactory streamFactory) Operation that writes a snapshot into a stream that is provided by the given CheckpointStreamFactory and returns a @RunnableFuture that gives a state handle to the snapshot.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_OPERATOR_STATE_NAME

public static final String DEFAULT_OPERATOR_STATE_NAME

The default namespace for state in cases where no state name is provided

See Also:

Constant Field Values

Constructor Detail

DefaultOperatorStateBackend

public DefaultOperatorStateBackend(ClassLoader userClassLoader)
                            throws IOException

Throws:

IOException

Method Detail

getRegisteredStateNames

public Set<String> getRegisteredStateNames()

Specified by:

getRegisteredStateNames in interface OperatorStateStore

close

public void close()
           throws IOException

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Throws:

IOException

dispose

public void dispose()

Description copied from interface: OperatorStateBackend

Disposes the backend and releases all resources.

Specified by:

dispose in interface OperatorStateBackend

getSerializableListState

public <T extends Serializable> ListState<T> getSerializableListState(String stateName)
                                                           throws Exception

Specified by:

getSerializableListState in interface OperatorStateStore

Throws:

Exception

getOperatorState

public <S> ListState<S> getOperatorState(ListStateDescriptor<S> stateDescriptor)
                              throws IOException

Specified by:

getOperatorState in interface OperatorStateStore

Throws:

IOException

getBroadcastSerializableListState

public <T extends Serializable> ListState<T> getBroadcastSerializableListState(String stateName)
                                                                    throws Exception

Throws:

Exception

getBroadcastOperatorState

public <S> ListState<S> getBroadcastOperatorState(ListStateDescriptor<S> stateDescriptor)
                                       throws Exception

Throws:

Exception

snapshot

public RunnableFuture<OperatorStateHandle> snapshot(long checkpointId,
                                           long timestamp,
                                           CheckpointStreamFactory streamFactory)
                                             throws Exception

Description copied from interface: Snapshotable

Operation that writes a snapshot into a stream that is provided by the given CheckpointStreamFactory and returns a @RunnableFuture that gives a state handle to the snapshot. It is up to the implementation if the operation is performed synchronous or asynchronous. In the later case, the returned Runnable must be executed first before obtaining the handle.

Specified by:

snapshot in interface Snapshotable<OperatorStateHandle>

Parameters:

checkpointId - The ID of the checkpoint.

timestamp - The timestamp of the checkpoint.

streamFactory - The factory that we can use for writing our state to streams.

Returns:

A runnable future that will yield a StateObject.

Throws:

Exception

restore

public void restore(Collection<OperatorStateHandle> restoreSnapshots)
             throws Exception

Description copied from interface: Snapshotable

Restores state that was previously snapshotted from the provided parameters. Typically the parameters are state handles from which the old state is read.

Specified by:

restore in interface Snapshotable<OperatorStateHandle>

Parameters:

restoreSnapshots - the old state to restore.

Throws:

Exception