org.apache.flink.runtime.checkpoint

Interface CompletedCheckpointStore

All Known Implementing Classes:

ZooKeeperCompletedCheckpointStore

public interface CompletedCheckpointStore

A bounded LIFO-queue of CompletedCheckpoint instances.

Method Summary

Modifier and Type	Method and Description
void	addCheckpoint(CompletedCheckpoint checkpoint) Adds a CompletedCheckpoint instance to the list of completed checkpoints.
List<CompletedCheckpoint>	getAllCheckpoints() Returns all CompletedCheckpoint instances.
CompletedCheckpoint	getLatestCheckpoint() Returns the latest CompletedCheckpoint instance or null if none was added.
int	getNumberOfRetainedCheckpoints() Returns the current number of retained checkpoints.
void	recover() Recover available CompletedCheckpoint instances.
void	shutdown() Shuts down the store and discards all checkpoint instances.
void	suspend() Suspends the store.

Method Detail

recover

void recover()
      throws Exception

Recover available CompletedCheckpoint instances.

After a call to this method, getLatestCheckpoint() returns the latest available checkpoint.

Throws:

Exception

addCheckpoint

void addCheckpoint(CompletedCheckpoint checkpoint)
            throws Exception

Adds a CompletedCheckpoint instance to the list of completed checkpoints.

Only a bounded number of checkpoints is kept. When exceeding the maximum number of retained checkpoints, the oldest one will be discarded via CompletedCheckpoint.discard(ClassLoader).

Throws:

Exception

getLatestCheckpoint

CompletedCheckpoint getLatestCheckpoint()
                                 throws Exception

Returns the latest CompletedCheckpoint instance or null if none was added.

Throws:

Exception

shutdown

void shutdown()
       throws Exception

Shuts down the store and discards all checkpoint instances.

Throws:

Exception

suspend

void suspend()
      throws Exception

Suspends the store.

If the implementation allows recovery, checkpoint state needs to be kept around. Otherwise, this should act like shutdown.

Throws:

Exception

getAllCheckpoints

List<CompletedCheckpoint> getAllCheckpoints()
                                     throws Exception

Returns all CompletedCheckpoint instances.

Returns an empty list if no checkpoint has been added yet.

Throws:

Exception

getNumberOfRetainedCheckpoints

int getNumberOfRetainedCheckpoints()

Returns the current number of retained checkpoints.