TinyREST allows a Java programmer to easily create a REST server without having to install a J2EE server. Creating a new server is as easy as copying the service jar, setting up a configuration file and writing your own service handler class. The resulting project can be made to start up as a service.
Annotations can now be used to write handler class and methods.
JDBC database access as well as file system access is allowed from the service.
Apache module for servicing Android JSON RPC requests, if you want to develop pure java applications without the the bloat of J2EE take a closer look...