For each desktop, events are processed sequentially, so thread model is simple. Like developing desktop applications, you don't need to worry about racing and multi-threading. All you need to do is to register an event listener and process the event when invoked.

Tip: Each event listener executes in an independent thread called event processing thread, while the ZUML page is evaluated in the servlet thread.

Tip: The use of the event processing thread can be disabled such that all events are processed in the Servlet threads. It has a little bit better performance and less integration issues. However, you can not suspend the execution. Refer to the Use the Servlet Thread to Process Events section in the Advanced Features chapter.