Package org.graylog2.cluster.lock

Class RefreshingLockService

java.lang.Object

org.graylog2.cluster.lock.RefreshingLockService

All Implemented Interfaces:

AutoCloseable

public class RefreshingLockService
extends Object
implements AutoCloseable

Service that can be used to acquire a Lock that will be refreshed periodically in a background thread. Each instance of the service needs to be closed to release the lock.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	RefreshingLockService.Factory

Constructor Summary

Constructors

Constructor	Description
RefreshingLockService(LockService lockService, ScheduledExecutorService scheduler, Duration lockTTL)

Method Summary

Modifier and Type	Method	Description
void	acquireAndKeepLock(String resource, int maxConcurrency)	Lock the given resource and ensure that only the given number of locks for the resource exist in the cluster.
void	acquireAndKeepLock(String resource, String lockContext)	Lock the given resource exclusively.
void	close()	Release the lock.
void	releaseLock()	Release the lock.

Methods inherited from class java.lang.Object

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

Constructor Details

RefreshingLockService

@Inject
public RefreshingLockService(LockService lockService,
 @Named("daemonScheduler")
 ScheduledExecutorService scheduler,
 @Named("lock_service_lock_ttl")
 Duration lockTTL)

Method Details

acquireAndKeepLock

public void acquireAndKeepLock(String resource,
 int maxConcurrency)
                        throws AlreadyLockedException

Lock the given resource and ensure that only the given number of locks for the resource exist in the cluster.

Parameters:

resource - the resource to lock

maxConcurrency - maximum number of locks for the resource

Throws:

AlreadyLockedException - when the resource couldn't be locked

acquireAndKeepLock

public void acquireAndKeepLock(String resource,
 String lockContext)
                        throws AlreadyLockedException

Lock the given resource exclusively.

Parameters:

resource - the resource to lock

lockContext - the identifier for the exclusive lock

Throws:

AlreadyLockedException - when the resource couldn't be locked

releaseLock

public void releaseLock()

Release the lock.

close

public void close()

Release the lock.

Specified by:

close in interface AutoCloseable