Package org.apache.activemq.broker

Interface Locker

All Superinterfaces:

Service

All Known Implementing Classes:

AbstractJDBCLocker, AbstractLocker, DefaultDatabaseLocker, LeaseDatabaseLocker, SharedFileLocker, TransactDatabaseLocker

public interface Locker
extends Service

Represents a lock service to ensure that a broker is the only master

Method Summary

Modifier and Type	Method	Description
void	configure(PersistenceAdapter persistenceAdapter)	Optionally configure the locker with the persistence adapter currently used You can use persistence adapter configuration details like, data directory datasource, etc.
boolean	keepAlive()	Used by a timer to keep alive the lock.
void	setFailIfLocked(boolean failIfLocked)	Specify whether to fail immediately if the lock is already held.
void	setLockable(LockableServiceSupport lockable)	A reference to what is locked
void	setLockAcquireSleepInterval(long lockAcquireSleepInterval)	set the delay interval in milliseconds between lock acquire attempts
void	setName(String name)	Set the name of the lock to use.

Methods inherited from interface org.apache.activemq.Service

start, stop

Method Detail

keepAlive

boolean keepAlive()
           throws IOException

Used by a timer to keep alive the lock. If the method returns false the broker should be terminated if an exception is thrown, the lock state cannot be determined

Throws:

IOException

setLockAcquireSleepInterval

void setLockAcquireSleepInterval(long lockAcquireSleepInterval)

set the delay interval in milliseconds between lock acquire attempts

Parameters:

lockAcquireSleepInterval - the sleep interval in miliseconds

setName

void setName(String name)

Set the name of the lock to use.

setFailIfLocked

void setFailIfLocked(boolean failIfLocked)

Specify whether to fail immediately if the lock is already held. When set, the CustomLock must throw an IOException immediately upon detecting the lock is already held.

Parameters:

failIfLocked - true => fail immediately if the lock is held; false => block until the lock can be obtained (default).

setLockable

void setLockable(LockableServiceSupport lockable)

A reference to what is locked

configure

void configure(PersistenceAdapter persistenceAdapter)
        throws IOException

Optionally configure the locker with the persistence adapter currently used You can use persistence adapter configuration details like, data directory datasource, etc. to be used by the locker

Parameters:

persistenceAdapter -

Throws:

IOException