PostStateChange interceptors are not given the correct state

[heffebaycay]

Let's say I have a state machine with the following structure :

Initial State --> Choice "Choice_State" :
                             (guard) --> State "One"
                             (else)  --> State "Default"

And I configure an Interceptor that looks just like this:

public class CustomInterceptor extends StateMachineInterceptorAdapter<CustomState, CustomEvent> {

    @Override
    public void preStateChange(State<Custom State, CustomEvent> state, Message<CustomEvent> message, Transition<Custom State, CustomEvent> transition, StateMachine<Custom State, CustomEvent> stateMachine) {
        System.out.printf("Interceptor - preState : %s\n", state.getId());
        super.preStateChange(state, message, transition, stateMachine);
    }

    @Override
    public void postStateChange(State<Custom State, CustomEvent> state, Message<CustomEvent> message, Transition<Custom State, CustomEvent> transition, StateMachine<Custom State, CustomEvent> stateMachine) {
        System.out.printf("Interceptor - postState : %s\n", state.getId());
        super.postStateChange(state, message, transition, stateMachine);
    }

Depending on what the guard function returns, the following paths are possible :

1. if guard returns true : Initial State --> "Choice_State" -> "One"

The interceptor prints the following info:

Interceptor - preState One
Interceptor - postState Choice_State

2. if guard returns false : Initial State --> "Choice_State" -> "Default"

The interceptor prints the following info:

Interceptor - preState Default
Interceptor - postState Choice_State

In both cases, I expected the postStateChangeInterceptor to show the same state as the preState interceptor.

I believe the culprit is the following call in AbstractStateMachine::switchToState :

callPostStateChangeInterceptors(state, message, transition, stateMachine);

When it should be

callPostStateChangeInterceptors(toState, message, transition, stateMachine);

The toState variable holds a reference to the actual state the state machine will transition to (after pseudo states transitions are followed), whereas the state variable holds a reference to the destination state before following pseudo states transitions.

[jvalkeal]

Hmm, for quick look you may be right about this. There's been no real use of post stage internally so this may have slipped from any existing tests. I'll try to poke around more to create some new tests.

[jvalkeal]

Fixed per 37642b1

[heffebaycay]

@jvalkeal Perfect, thanks for the fix :)