org.apache.hadoop.hbase.procedure2.store

Interface ProcedureStore

All Known Implementing Classes:

WALProcedureStore

@InterfaceAudience.Private
@InterfaceStability.Evolving
public interface ProcedureStore

The ProcedureStore is used by the executor to persist the state of each procedure execution. This allows to resume the execution of pending/in-progress procedures in case of machine failure or service shutdown.

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static interface	ProcedureStore.ProcedureStoreListener Store listener interface.

Method Summary

Methods

Modifier and Type	Method and Description
void	delete(long procId) The specified procId was removed from the executor, due to completion, abort or failure.
int	getNumThreads()
void	insert(Procedure proc, Procedure[] subprocs) When a procedure is submitted to the executor insert(proc, null) will be called.
boolean	isRunning()
Iterator<Procedure>	load() Load the Procedures in the store.
void	recoverLease() Acquire the lease for the procedure store.
void	registerListener(ProcedureStore.ProcedureStoreListener listener) Add the listener to the notification list.
void	start(int numThreads) Start/Open the procedure store
void	stop(boolean abort) Stop/Close the procedure store
boolean	unregisterListener(ProcedureStore.ProcedureStoreListener listener) Remove the listener from the notification list.
void	update(Procedure proc) The specified procedure was executed, and the new state should be written to the store.

Method Detail

registerListener

void registerListener(ProcedureStore.ProcedureStoreListener listener)

Add the listener to the notification list.

Parameters:

listener - The AssignmentListener to register

unregisterListener

boolean unregisterListener(ProcedureStore.ProcedureStoreListener listener)

Remove the listener from the notification list.

Parameters:

listener - The AssignmentListener to unregister

Returns:

true if the listner was in the list and it was removed, otherwise false.

start

void start(int numThreads)
           throws IOException

Start/Open the procedure store

Parameters:

numThreads -

Throws:

IOException

stop

void stop(boolean abort)

Stop/Close the procedure store

Parameters:

abort - true if the stop is an abort

isRunning

boolean isRunning()

Returns:

true if the store is running, otherwise false.

getNumThreads

int getNumThreads()

Returns:

the number of threads/slots passed to start()

recoverLease

void recoverLease()
                  throws IOException

Acquire the lease for the procedure store.

Throws:

IOException

load

Iterator<Procedure> load()
                         throws IOException

Load the Procedures in the store.

Returns:

the set of procedures present in the store

Throws:

IOException

insert

void insert(Procedure proc,
          Procedure[] subprocs)

When a procedure is submitted to the executor insert(proc, null) will be called. 'proc' has a 'RUNNABLE' state and the initial information required to start up. When a procedure is executed and it returns children insert(proc, subprocs) will be called. 'proc' has a 'WAITING' state and an update state. 'subprocs' are the children in 'RUNNABLE' state with the initial information.

Parameters:

proc - the procedure to serialize and write to the store.

subprocs - the newly created child of the proc.

update

void update(Procedure proc)

The specified procedure was executed, and the new state should be written to the store.

Parameters:

proc - the procedure to serialize and write to the store.

delete

void delete(long procId)

The specified procId was removed from the executor, due to completion, abort or failure. The store implementor should remove all the information about the specified procId.

Parameters:

procId - the ID of the procedure to remove.