java - How to finish a container-managed transaction before running a long task? -


i have task consists of 3 steps prepare, execute, update. prepare , update need work within transaction, whereas execute takes long (i.e. several minutes hours). task part of ejb, i.e.: 

@stateless public class task {     public void dotask() {         prepare();         execute();         update();     } }

my question is, there (elegant) way commit , finish transaction after prepare , start new 1 before update? i'd rather use container-managed transactions , possibly not switch use usertransaction.

it possible split tasks single ejbs if gains advantage, note suspending transaction execute (i.e. using @transactional(txtype.not_supported) not enough since still triggers timeout.

i tried split taskexecute class has @asynchronous @transactional(not_supported) public void execute() , sending event when done. doesn't seem work either.

is there way this?

after further testing let me conclude: alexanders reply absolutely correct. understanding had altered. foremost, wasn't aware @transactional not work on ejbs, on cdi beans. ejbs annotation called @transactionattribute , can set same values. combination of @asynchronous , @transactionattribute(not_supported) work (if not waiting result).

it depends on version of java ee want use. here 3 possible solutions.

  • use jms, send appropriate message , execute in mdb (any version, full profile required)
  • use java ee 6.0's timer service , schedule task perform execute asynchronously (@timeout)
  • use java ee 7.0's batch processing api schedule proper long running batch job.

the latter looking for, available in java ee 7.0 , up. otherwise, jms solutions cleanest, if jms not option, timer service should work.


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