Say you have two events: Action1 and Action2. When you receive Action1, you want to store some arbitrary data to be used the next time Action2 rolls around. Optimally, Action1 is normally a command however it can also be other events. The idea is still the same.

The current way I am implementing this is by storing state and then simply checking when Action2 is called if that specific state is there. This is obviously a bit messy and leads to a lot of redundant code. Here is an example of how I am doing that, in pseudocode form (and broken down quite a bit, obviously):

void onAction1(event) {
    Player = event.getPlayer()
    Player.addState("my_action_to_do")
}

void onAction2(event) {
    Player = event.getPlayer()

    if not Player.hasState("my_action_to_do") {
        return
    }

    // Do something
}

When doing this for a lot of other actions it gets somewhat ugly and I wanted to know if there is something I can do to improve upon it.

I was thinking of something like this, which wouldn't require passing data around, but is this also not the right direction?

void onAction1(event) {
   Player = event.getPlayer()
   Player.onAction2(new Runnable() {

       public void run() {
           // Do something
       }

   })
}

If one wanted to take it even further, could you not simply do this?

void onPlayerEnter(event) { // When they join the server
    Player = event.getPlayer()
    Player.onAction1(new Runnable() {

       public void run() {

           // Now wait for action 2
           Player.onAction2(new Runnable() {
               // Do something
           })

       }

    }, true) // TRUE would be to repeat the event,
             // not remove it after it is called.
}

Any input would be wonderful.