I am looking at the websocket-chat example. It unveils much, but I still cannot get something. I understand how messages are received, processed and sent on the web page side.

However, Play captures websocket messages by means of the receive method of an Akka actor. In the websocket-chat, there are several cases in this method, but I don't get, how does it know which websocket message should be mapped to which case. In fact, I don't understand the path that a websocket message follows upon entering Play's domain, how is it processed and how can different message types/kinds be sent from the webpage.

I have not find any info or sources related to this. Could please someone explain this or point to some kind of a good reference?

UPDATE:

The link to the original example.