net.sf.sasl.aop.distributed.lock.annotation.mutex
Annotation Type DistributedDynamicMutexLockKey

@Documented
@Retention(value=RUNTIME)
@Target(value={METHOD,PARAMETER})
public @interface DistributedDynamicMutexLockKey

Annotation to declare a dynamic resolved lock key by a input parameter. For example to protect against concurrent modifications of a customer which may cause inconsistency, the customer id could be used as a potential lock key.

Since:

0.0.1 (sasl-aop-distributed-lock)

Author:

Philipp Förmer

Optional Element Summary

String	lockKeySelectorPath Defines a path to a class attribute or a getter method thats value should be used as the lock key.
DistributedDynamicMutexLockKey.LockKeySelectorType	lockKeySelectorType Defines how the lock key selector path should be interpreted.
int	lockOrderNumber If multiple locks should be done, than the lock order number (=lock priority) defines in which order the locks should be done.
long	maxLockWaitTime The maximum amount of milliseconds to wait for get the mutex locked.
int	parameterIndex If the annotation is used at method level, than this declares the parameter index to which it belongs.
String	postfix A postfix string that should get appended to the end of the mutex lock key.
String	prefix A prefix string that should get pushed before the mutex lock key.

lockKeySelectorType

public abstract DistributedDynamicMutexLockKey.LockKeySelectorType lockKeySelectorType

Defines how the lock key selector path should be interpreted. A path could be used, to use nested objects of a parameter as a lock key. The default value is LockKeySelectorType.NONE which means that the toString() method should be invoked on the parameter direct, to get the key to lock.

Default:

net.sf.sasl.aop.distributed.lock.annotation.mutex.DistributedDynamicMutexLockKey.LockKeySelectorType.NONE

lockKeySelectorPath

public abstract String lockKeySelectorPath

Defines a path to a class attribute or a getter method thats value should be used as the lock key. For example if the parameter is of type "CustomerDTO" than the path "customer.customerId", will select the customer id as the lock key, if the path qualifier type is set to LockKeySelectorType.ATTRIBUTE. The default value is "".

Default:

""

parameterIndex

public abstract int parameterIndex

If the annotation is used at method level, than this declares the parameter index to which it belongs. Should be otherwise ignored.

Default:

-1

prefix

public abstract String prefix

A prefix string that should get pushed before the mutex lock key. For example "customer-id-lock-". The default value is "".

Default:

""

postfix

public abstract String postfix

A postfix string that should get appended to the end of the mutex lock key. For example "-customer-id-lock". The default value is "".

Default:

""

maxLockWaitTime

public abstract long maxLockWaitTime

The maximum amount of milliseconds to wait for get the mutex locked. Values lesser or equal to zero mean eternal wait time. The default value is zero.

Since:

0.0.1 (sasl-aop-distributed-lock)

Default:

0L

lockOrderNumber

public abstract int lockOrderNumber

If multiple locks should be done, than the lock order number (=lock priority) defines in which order the locks should be done. Lower values mean lock first. If there are multiple annotations with the same order number, than the lock order for these is arbitrary. The default value is Integer.MAX_VALUE. A lock order should be always declared, as it reduces deadlock problems.

Since:

0.0.1 (sasl-aop-distributed-lock)

Default:

2147483647