Mantis is an annotation processor framework invoked by APT. It's purpose is to provide an extensible framwwork for annotations and corresponding processors. It currently has one built-in processor that will generate TCH (Test Case Harness) test xml files based on annotated junit source code. Milton has a Mantis processor for generating Control Test client code.
Mantis is extensible. To write your own mantis processor, simply extend AbstractMantisProcessor. Mantis processors are required to "play nice" with other mantis processors. Any files a processor creates must be "registered" so they are available to other processors. In this way, processors can be used by other processors, by themselves, or in a chain. Once you have your own mantis processor, you can add an entry to mantis' configuation file (mantis.properties), which maps annotation package names to the processor class. Only one processor is allowed per annotation package. In the future, mantis will support the creation of junit source code based on an annotated class.