Listeners, load a class on startup and creating threads in infinite loop

This is an identical post to the one I made in the jsp forum. I do this as I know, being a regular here, that there are equally good people(in j2ee web application development) in both these forum, but many of them stick to their particular forums of choice - jsp / servlets.
I was wondering if there is any means by which I could launch my own class when tomcat starts (in the same jvm).
1. I need one or more Thread/TimerTask because the requirement is such that the application would have continous data drops (in the form of logs) which has to be picked up, parsed and pushed into a db. Another part of the application reads the data from the db on requests (http) and displays it over the web. The thread has to poll for arrival of new logs and then hand it over to a framework for parsing and inserting the parsed data to a db.
2. I know that I can possibly use a servlet with a load-on-startup value greater than 1 and code my requirement into the init method. However, using a servlet for a functionality different from servicing http requests has me worried. (valid ?), not to mention the fact that Iam very uneasy about creating threads from within Servlets.
3. I googled hard and found that I could probably use a tomcat specific context lifecycle listener.
4. I could also possibly use the servlet api - the ServletContextListener.
5. I have rejected #2 and settled on either #3 or #4 - the ServletContextListener or Tomcat specific Lifecycle Listener, though the later, as I said binds me to Tomcat (which is ok for me). Are there any other specific (dis)advantages of using either especially when I have to create threads from within them (on context startup)? Other than memory leaks, killing the thread objects & associated resources on context shutdown, is there anything else that I need to watch out for while using threads.
6. I wonder is there is there a plain startup hook available in tomcat (rather than listeners) - from where I can launch a class that starts a thread in the same jvm as tomcat's ?
Thanks In Advance,
Ram.

Anybody ? Sorry for bumping up.
Thanks,
Ram.

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