de.adorsys.lockpersistence.service

Class LockServiceTemplate

java.lang.Object

de.adorsys.lockpersistence.service.LockServiceTemplate

All Implemented Interfaces:

LockService

public class LockServiceTemplate
extends Object
implements LockService

Constructor Summary

Constructors

Constructor and Description
LockServiceTemplate(LockPersistenceRepository repository, Long expiryInterval)

Method Summary

Modifier and Type	Method and Description
Lock	create(String name) Acquire a lock by name.
Iterable<Lock>	findAll() Iterate the existing locks.
Lock	refresh(String name, String value) The holder of a lock can refresh it, extending its expiry.
void	release(String name, String value) Release a lock before it expires.

Methods inherited from class java.lang.Object

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

Constructor Detail

LockServiceTemplate

public LockServiceTemplate(LockPersistenceRepository repository,
                           Long expiryInterval)

Method Detail

findAll

public Iterable<Lock> findAll()

Description copied from interface: LockService

Iterate the existing locks.

Specified by:

findAll in interface LockService

Returns:

an iterable of all locks

create

public Lock create(String name)
            throws LockExistsException

Description copied from interface: LockService

Acquire a lock by name. Only one process (globally) should be able to obtain and hold the lock with this name at any given time. Locks expire and can also be released by the owner, so after either of those events the lock can be acquired by the same or a different process.

Specified by:

create in interface LockService

Parameters:

name - the name identifying the lock

Returns:

a Lock containing a value that can be used to release or refresh the lock

Throws:

LockExistsException

release

public void release(String name,
                    String value)
             throws LockNotHeldException

Description copied from interface: LockService

Release a lock before it expires. Only the holder of a lock can release it, and the holder must have the correct unique value to prove that he holds it.

Specified by:

release in interface LockService

Parameters:

name - the name of the lock

value - the value of the lock (which has to match the value when it was acquired)

Throws:

LockNotHeldException

refresh

public Lock refresh(String name,
                    String value)
             throws LockNotHeldException

Description copied from interface: LockService

The holder of a lock can refresh it, extending its expiry. If the caller does not hold the lock there will be an exception, but the implementation may not be able to tell if it was because he formerly held the lock and it expired, or if it simply was never held.

Specified by:

refresh in interface LockService

Parameters:

name - the name of the lock

value - the value of the lock (which has to match the value when it was acquired)

Returns:

a new lock with a new value and a new expiry

Throws:

LockNotHeldException - if the value does not match the current value or if the lock doesn't exist (e.g. if it expired)