jdbc and kill -14

I put this on some java forums and was told it wasn't possible. We have background processes that wake up and do some data processing. These processes are in java and connect through the JDBC. We have a shutdown script that will kill -14 these processes. The problem is that if they have performed DML(and have not committed), they commit when the process is killed. This leaves data in an erroneous state because all the processing was not finished and yet some of the dml was committed. We have a need to periodically shut down the application for maintenance. I can code a work around to wait for the processes to finish(create a shutdown_normal and a shutdown_immediate mimimicking oracle functionality), however, I am wondering if there is an API to tell Oracle to rollback instead of commit? I thought it was the autocommit, but it does not seem to work the same way as the one for sqlplus. All turning off the autocommit seems to do is stop every sql statement from immediately being committed. Thanks

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