Avoid optimistic locking in java web application

Question

I have a problem concerning java optimistic locking exception. I have a service class that is instantiated (by spring) for every new user session and it contains a non static method that perform db operations. I wonder how I can avoid optimistic locking exception on the entity that is read/written to db. I would like to achieve a similar result as a synchronized method would but I guess using "synchronized" is out of the question since the method is not static and would not have any effect when users have own instances of the service? Can I somehow detect if a new version of the entity is saved to db and then retrieve a new version and then edit and save that one? I want the transaction to hold until it is ok even if it implies the transaction have to wait for other transactions. My first idea was to put the transaction code into a try-catch block and then retry the transaction (read & write) if optimistic locking exceptions is thrown. Is that solution "too easy" or?

Answer 1

Optimistic locking is used to improve performance, but still avoid messing up the data.

If there's an Optimistic lock failure, the user (that failed the update) needs to decide if he wants to do his operation again. You can't automate that, since it depends entirely on what was changed and how.

So no, your idea of a retry the transaction with a try/catch is not a "too easy solution". It's not a solution, it would be a serious (and dumb) bug.