For a meta websearch application a monitor program written in Java was needed that checks at a specified interval which search engines are available. Both as a warning system, the webmaster receives an email, as to prevent unnecessary queries.
A small Java servlet was also created, so the status of the monitor can be checked using a web browser. The Java servlet communicates with the monitor using the XML-RPC protocol, a light weighted remote procedure call mechanism using XML.
The configuration of the web server monitor program is also stored as inside XML file.