When we make a call to method actorOf, what we get in return is an ActorRef that in turn also possesses a particular path where we've created the Actor. With this call, we know exactly there's an Actor instance created, been assigned a unique ID, and hook methods are called. There's this method named preStart() that gets called as the very first action, after a new Actor is created.
A few points to note when a new Actor is created:
- A new Actor path is reserved for the Actor
- A unique ID is assigned to the Actor
- After the instance is created, the
preStart()method is called:
When an Actor is restarted:
- The
preRestart()is called on the instance. - New instance is created, replaces the old instance.
- The
postRestart()method is called.
When an Actor is stopped:
- The
postStop()method is called on the instance. - Terminated message is sent to watchers.
- Actor path is allowed to be used again.
The previous diagram illustrates this whole cycle. An important point to note is that we...