Java Plugin Framework (JPF)

JPF provides a runtime engine that dynamically discovers and loads \"plug-ins\". A plug-in is a structured component that describes itself to JPF using a \"manifest\". JPF maintains a registry of available plug-ins and the functions they provide (via extension points and extensions). One major goal of JPF is that the application (and its end-user) should not pay any memory or performance penalty for plug-ins that are installed, but not used. Plug-ins are added to the registry at application start-up or while the application is running but they are not loaded until they are called.