Velocity, Freemarker, Japid, Rythm, any other? What i am looking for is a solution similar to what JSP provides in servlet environment. It should be a form of ViewProcessor implementation, but working on standalone embedded Grizzly deployment(NIO architecture).
Jersey has support for freemarker templates - see jersey-freemarker module on maven. It works with any container (i.e. is not depending on servlet). There is also freemarker sample in Jersey workspace that shows how to use it - see here.