Package org.zkoss.zk.ui.event

Interface EventThreadResume

public interface EventThreadResume

Used to listen after the event processing thread is resumed.

How this interface is used.

1. First, you specify a class that implements this interface in WEB-INF/zk.xml as a listener.
2. Then, when a suspended event thread is being resumed, an instance of the specified class is constructed and beforeResume(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.event.Event) is called first in the main thread (i.e., the servlet thread), right before resuming. And then, afterResume(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.event.Event) is invoked in the event processing thread, after the thread is resumed.

In addition to resuming normally, a suspended event thread might be aborted (usually caused by destroying the desktop owning the event thread). In this case, abortResume(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.event.Event) is called instead of beforeResume(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.event.Event) and afterResume(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.event.Event).

Author:

tomyeh

Method Summary

Modifier and Type	Method	Description
void	abortResume(Component comp, Event evt)	Called when the suspended event thread is aborted.
void	afterResume(Component comp, Event evt)	Called after the suspended event thread is resumed.
void	beforeResume(Component comp, Event evt)	Called just before the suspended event thread is resumed.

Method Details

beforeResume

void beforeResume(Component comp,
 Event evt)
           throws Exception

Called just before the suspended event thread is resumed. Unlike afterResume(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.event.Event), it executes in the main thread that resumes the suspended event processing thread.

If this method throws an exception, it will abort the execution and shows an error message to the end user. Note: EventThreadCleanup.cleanup(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.event.Event, java.util.List<java.lang.Throwable>) won't be called if an exception is thrown in this method, since it executes in the main thread.

Throws:

Exception

afterResume

void afterResume(Component comp,
 Event evt)
          throws Exception

Called after the suspended event thread is resumed. Unlike beforeResume(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.event.Event), it executes in the event processing thread that is resumed.

If this method throws an exception, it will abort the execution and shows an error message to the end user (unless it is cleaned up by EventThreadCleanup.cleanup(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.event.Event, java.util.List<java.lang.Throwable>)).

Throws:

Exception

abortResume

void abortResume(Component comp,
 Event evt)
          throws Exception

Called when the suspended event thread is aborted. It is called in the main thread (i.e., the servlet thread).

If a suspended event thread is resumed normally, beforeResume(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.event.Event) and afterResume(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.event.Event) are called. On the other hand, if it is aborted (usually caused by destroying the desktop that owns this thread), abortResume(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.event.Event) is called instead.

Note: if the suspended thread is aborted, none of beforeResume(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.event.Event), afterResume(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.event.Event), EventThreadCleanup.cleanup(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.event.Event, java.util.List<java.lang.Throwable>), and EventThreadCleanup.complete(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.event.Event) will be called. Thus, you have to do necessary cleanups in this method.

Throws:

Exception