Runtime components : Core components : Events : Concepts : How the event manager handles remote events
  
How the event manager handles remote events
When the application registers the client workstation's event manager as a handler of a specific remote event, the following occurs:
1 The application invokes the registerInterestInRemoteEvent method in the client workstation's event manager instance and passes the following information as arguments:
The event name
The notifier name
The context in which the operation registering the interest is running
If there is more than one session from the client to different servers, the name of the Client/Server mechanism (Java Connector) instance that is managing the session.
2 The event manager instantiates an EventManagerClientOperation to manage the communication between event managers on the client and server workstations. The event manager then invokes the send method of the appropriate Client/Server Mechanism instance to start the remote EventManagerServerOperation.
3 On the server side, the Client/Server mechanism instantiates and runs the EventManagerServerOperation.
4 The remote operation's run method calls the addHandler method of the server workstation's event manager and passes the event name, the notifier name, and the Terminal Identifier (TID) of originating workstation (set as an EventManagerServerOperation attribute by the Client/Server Mechanism) as arguments.
5 The server event manager then registers itself as a handler of the specified event to the specified local notifier. The event manager maintains the client TID in its remote events table (the workstationList attribute) along with the name of the event and the event's notifier.
6 When the notifier signals the event, the event manager's invoke the sendEvent method in the Client/Server mechanism passing the client workstation's TID as an argument. This ends the EventManagerServerOperation's process and returns control to the Client/Server Mechanism that started the operation.
7 The Client/Server Mechanism creates a CSReplyEvent and sends it as a reply to the client workstation.
8 On the client workstation, the EventManagerClientOperation instance is listening for a CSReplyEvent. When it receives this event, the operation calls the receive method in the Client/Server Mechanism and checks for the correct execution of the remote operation. The client operation ends and the client event manager and regain control.
9 The event manager can then notify the application of the remote event.
When the application needs to send an event from the client to the server, it can use the registerServerInterestInEvent of the event manager to register the server workstation as a handler of the event. In the event manager's events table, the server TID is replaced by the identifier of the CSClient instance identifying the session between the two workstations. When the notifier signals the event, the EventManager's dispatch method sends the event to the workstation identified by the CSClient instance.
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