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I think, Volatile can help. declare all the bean variable as volatile.

You could also have a LastModified column. Any thread before doing a write, checks this column - if the date it has is earlier than the table date, then the thread again has to read the data and re-do the modifications.

If First thread is going to edit row data, First thread should take a read lock on the table row data, so that thread2 does not read a stale data which is going to be changed.

There is something called MESI protocol for multi-processor system. Similar kind of protocol can be used for multiple threads.

What about synchronized methods? "If an object is visible to more than one thread, all reads and writes to that object's variables are done through synchronized methods." : "h t t p://docs.oracle.com/javase/tutorial/essential/concurrency/syncmeth.html"

how about to use jboss cache service.... it will read the data from cache before executing the update sql each time. and after update will update cache also

We can create queue for data base tasks. So all the threads will push their DB related task on db queue. The DB processing thread pops the tasks from queue and updates the data from DB and then process task.

This is called as scheduled-task pattern.

Use the version number concept like ORM does.

Have your update statement where clause to include the version that you read.

update *** set f1= value,versionnum=versionnum+1 where versionnum=<<versionnumber that you read>>

If other thread already commited, this update will be a no op.

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We can use two mutex one for a flag and other for writing data in database. Each thread before writing to data in database it will check flag.

consider using optimistic locking.