Hi. I'm interested in creating a servlet that is similar to superTweet.net

SuperTweet.Net - Twitter API OAuth Proxy - Command-line Twitter

This web service receives data from any client and tweets it to Twitter.
I have no knowledge of how it works, but I can guess that a servlet is constantly watching the incoming data.

The host does not know when a client sends the data. Perhaps the data is cached somewhere until the servlet decides to obtain it in a routine mannar.

Could anyone give me some tips how to develop a servlet like this?