UnboundedPriorityMailbox has the option to prioritize messages by type (like int string etc.). Is it possible to prioritize messages by type of class property?
I mean, I know that option is available:
case x: Int => 1
// String Messages
case x: String => 0
// Long messages
case x: Long => 2
// other messages
case _ => 3
And the order (priority) of the messages will be:
myPriorityActor ! “Hello”
myPriorityActor ! “I am priority actor”
myPriorityActor ! “I process string messages first,then integer, long and others”
myPriorityActor ! 5
myPriorityActor ! 3
myPriorityActor ! 1
myPriorityActor ! 6.0
myPriorityActor ! 5.0
Link to example : https://medium.com/knoldus/how-to-create-a-priority-based-mailbox-for-an-akka-actor-232b488e33d4
I would like to know if I can prioritize the queue by type of Class property.
For example:
case x: Student.name=> 1
// String Messages
case x: Student.salary=> 0
// Long messages
case x: Student.School=> 2
Is such a thing possible?
Fundamentally, this has nothing to do with Akka. All you are doing is returning a partial function that has the interface of accepting an Any and returning an Int. Yes, behind the scenes that function will be used to determine the priority of a message, but from Akka's perspective it doesn't know anything about your function. The Mailbox just calls the function you provide to determine a relative priority for each message it receives.
The point being this is really a Scala question and you might be better off asking your question with just a Scala tag: you want to write a partial function function that looks at "class property" and returns an Int.
I think the answer to your question is no, but I'm not 100% sure I'm understanding your question. I think the key to the answer is understanding what I just said above though: there is no magic here. You are just providing a partial function that accepts an Any and returns an Int (or isn't applicable). The Scala pattern matching is doing some automatic detection of types and conversion of types, but you could do the same (in more lines of code) just by doing a bunch .getClass calls within if statements yourself.
So the only real question you have to answer is "could I write an if statement that does this?"
Thus, if my function receives the input of "Thomas Jefferson" could you write if statements that convert that into Int value corresponding to its message priority. Instinctively, I don't think you could. Because I would expect that both Student.name and Student.School are both String types and you would have a hard time distinguishing between them. Thus there's no if statement I could write that could tell between "Thomas Jefferson" the person and "Thomas Jefferson" the school. But, on the other hand, it all depends on how you are defining your types. Maybe you've subclassed String for school. In which case you could look at the types and tell the difference.
But, again, the bottom line is that this is just a function that converts Anys into Ints. If you can write function that does that, Akka will utilize that function to determine the priority of the message.
Although I'd also assert that this problem is somewhat moot in the real world. Prioritized mailboxes are pretty rare in real world applications and in cases where you have them you are probably not sending simple types. Most messages are likely some kind of envelope and won't be a simple type. You'll easily be able to tell the difference between a "HighPriorityCancel" message and a "GetGrade" message via the envelope.