Threads in Web Logic??

Question

I read somewhere that Web Logic doesn't suggest to use any other threads from the web..is it true? I have the following situation:
We have a servlet, which calls a method in a Java class..this method may take long time at times. So to avoid it, I need a mechanism to load the data in sequances in the background and say when one sequance is loaded, load it on the web..so this way even if there is a large data, my servlet won't throw the OutOfMemoryException. This is just a thought. Would someone suggest me any better solution or anything that would help me in achieving what I'm trying to do?
Thanks

Answer 1

Several solutions.
First don't do it in the first place. Find another solution that is faster and/or doesn't use as much data. This can include simply disallowing the user from doing anything that messes with large data sets. Or using a stored procedure rather than java to do the processing.
After that there are a number of solutions:
1. Use a batch server (seperate process.) It takes requests and processes them. The interface to this can be done any of several ways: sockets, RMI, JMS. Since the server is seperate you can also queue requests. A variation on this is to write the request to a database table(s) and the batch server processes anything new it finds (this is very useful if you need to track the processing.)
2. Web Logic (and all containers as far as I know) allow you to load classes outside of the container itself. Those classes can do anything you want and will be visible to classes in the container. Again you would want to implement this in some queue fashion.
3. Create the thread. The restriction against threads in a container is due to the nature of the container and because it might lead to problems. As far as I know no container prevents you from doing it. You know how your system will be used so you should be able to determine what the potential effect will be. You can even write mitigation strategies to help with potential future problems (such as using a thread.)