Can I perform an action in response to an event without changing state in stateless4j?

Question

Using stateless4j I am trying to perform an action in response to an event with parameters in one particular state. After handling the event I don't want to change state.

As stateless4j does not support actions on events (although I see there is a pending patch for this) I am instead misusing the permitDynamic() and using the selector to execute my action. I then return the same state in the selector. So, in the code below action_activated_serviceRegistered returns FsmState.ACTIVATED.

   activationFsmConfig
        .configure(FsmState.ACTIVATED)
        .onEntry(fsmFunctions::action_activated_entry)
        .onExit(fsmFunctions::action_activated_exit)
        .permitDynamic(new TriggerWithParameters1<>(Trigger.SERVICE_REGISTERED, ServiceReference.class), fsmFunctions::action_activated_serviceRegistered);

The issue I am having is that the exit and entry actions to my state are firing even though I am not changing state.

Is there a better way of doing this?

Answer 1

Perhaps you can perform your action in guard condition of .ignoreIf(Trigger, guard).