Similarly, you might have to clean up an event processing thread after it has processed an event.

A typical example is to close the transaction, if it is not closed properly.

To cleanup the event processing threads, you have to register a listener class, that implements the org.zkoss.zk.ui.event.EventThreadCleanup interface, to the listener element in the WEB-INF/zk.xml file.

<zk>
    <listener>    
        <listener-class>my.MyEventThreadCleanup</listener-class>        
    <listener>    
</zk>