java - how to raise OptimisticLockException -

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unable catch optimistic lock exception.

one way raise optimisticlockexception using em.flush()

try{    //some enitity    em.flush()   } catch(optimisticlockexception ole){}

but dont think best solution beacuse in full database flush.

another work around catching ejbexception , find rollbackexception in ..

       try{             // code         }        catch (ejbexception ex) {            if (ex.getcausedbyexception().getcause().tostring().               indexof("javax.transaction.rollbackexception")!= -1){                    // work               }                }        }

please have other idea or tell me way better.

i think first way reasonable way if want catch optimisticlockexception , refresh data or retry operation. second way, if current transaction not active, there no rollbackexception thrown.


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