About optimistic

manual

Locking in JPA

Explains how to use optimistic locking and pessimistic locking in JPA. JPA 2 supports both optimistic locking and pessimistic locking . Locking is essential to avoid ... i.e. each database object is locked separately. Optimistic locking is applied on transaction commit. Any database object that ... by another transaction. When using ObjectDB, optimistic locking is enabled by default and fully automatic. Optimistic ...

 
manual

Advanced JPA Topics

Describes advanced JPA topics - detached entity objects, lock management and entity lifecycle events. This section discusses advanced JPA topics: Detached Entity Objects Locking in JPA JPA Lifecycle Events Shared (L2) Entity Cache JPA Metamodel API ...

 
forum_thread

Optimistic Locking

We are having problems with optimistic locking.  I made a simple test case to try to induce an optimistic lock.... We are having problems with optimistic locking. I made a simple test case to try to induce an optimistic lock. I have two users logged on to our system.  They both read ...

 
api-jpa

LockModeType.OPTIMISTIC

Optimistic lock.(Enum Constant of javax.persistence.LockModeType)

 
forum_thread

Remove a modified entity cause an optimistic lock exception

Hello, the following examples load and modify an entity, and load and remove the same entity. The first example 'SetAndRemoveIssue.java' is a simple java program which executes without errors. The second example is an OSGi program which fails with an optimistic lock exception. Both examples are equivalent, please execute SetAndRemoveIssue.java (in the OSGi example as a plugin-test). Can you explain the optimistic lock exception? ... The second example is an OSGi program which fails with an optimistic lock exception. Both examples are equivalent, please execute ... example as a plugin-test). Can you explain the optimistic lock exception? It seems that the first level cache contains ...

 
forum_thread

Optimistic lock failed

Hi, I frequently see exceptions during development such as com.objectdb.o._RollbackException: Failed to commit transaction: Optimistic lock failed for object com.example.MyEntity#3 (object has version 1 instead of 3) Could you please explain what this means, and what I can do about it. Thanks you, Carl     ... Failed to commit transaction: Optimistic lock failed for object com.example.MyEntity#3 (object has version 1 ... If you must avoid optimistic lock exceptions you can use pessimistic exceptions, but it is more efficient to remain with optimistic locking (which is the default) and just handle these exceptions. ...

 
forum_thread

Optimistic lock failed : object has version .. instead of ..

I do basic storage and retrieval of Record class. When I stress the retrieval/storage with Apache JMeter sometimes (at some requests) I get this exception.   [ObjectDB 2.5.0] javax.persistence.OptimisticLockException Optimistic lock failed for object entities.Record#'1405/838/2011/121' (object has version 125 instead of 126) (error 673) at com.objectdb.jpa.EMImpl.beforeCompletion(EMImpl.java:381) ... Thank you! ... 2.5.0] javax.persistence.OptimisticLockException Optimistic lock failed for object entities.Record#'1405/838/2011/121' ... 2013-06-18 13:58 Optimistic locking is explained in this manual page . ...

 
forum_thread

Optimistic locking failure

Optimistic locking failure: I am using a Semaphore to force this execution of concurrents transactions T1 and T2 that cause parallel updates to A/B but it does not throw an OptimisticLockException and roll back. ... 2012-04-30 16:02 Optimistic locking failure: I am using a Semaphore to force this ... again. To support this, starting build 2.3.7_24  OPTIMISTIC (READ) is implemented as  OPTIMISTIC_FORCE_INCREMENT (WRITE) ...

 
forum_thread

Optimistic lock

Hello When I get an optimistic lock on an object, refresh(), start trans and persist?  Will the changes made to the object before the violation be retained or must they be duplicated in the retry code?  Assuming it affects only one object.  tia. ... Hello When I get an optimistic lock on an object, refresh(), start trans and persist?  Will ...

 
forum_thread

Optimistic locking: prevent version increment on entity collection attribute

Hello, I have an entity E with an attribute which is a collection of entities (one to many relationship) with an optimistic locking strategy supported by a version field. Is it possible to prevent the increment of the version of entity E when entities are added to or removed from the collection? Something like the equivalent of @OptimisticLock(excluded=true) in Hibernate? Thanks, Farid ... collection of entities (one to many relationship) with an optimistic locking strategy supported by a version field. Is it possible to ...