You could use akka[1] library to build a state machine, actor model is great for building state machines [2]. I have built one in the past using akka. Library i

You could use akka[1] library to build a state machine, actor model is great for building state machines [2]. I have built one in the past using akka. Library is pretty robust and well maintained. [1] http://akka.io http://akka.io [2] http://erlang.org/documentation/doc/4.8.2/doc/design_principles/fsm.html http://erlang.org/documentation/doc/4.8.2/doc/design_princip... [3] http://doc.akka.io/docs/akka/current/java/fsm.html http://doc.akka.io/docs/akka/current/java/fsm.html