org.zkoss.zk.ui.impl.EventProcessor Maven / Gradle / Ivy
/* EventProcessor.java
Purpose:
Description:
History:
Tue May 8 14:10:54 2007, Created by tomyeh
Copyright (C) 2007 Potix Corporation. All Rights Reserved.
{{IS_RIGHT
This program is distributed under LGPL Version 2.1 in the hope that
it will be useful, but WITHOUT ANY WARRANTY.
}}IS_RIGHT
*/
package org.zkoss.zk.ui.impl;
import org.zkoss.util.logging.Log;
import org.zkoss.zk.ui.Session;
import org.zkoss.zk.ui.Execution;
import org.zkoss.zk.ui.Desktop;
import org.zkoss.zk.ui.Page;
import org.zkoss.zk.ui.Component;
import org.zkoss.zk.ui.event.Event;
import org.zkoss.zk.ui.ext.Scope;
import org.zkoss.zk.ui.ext.Scopes;
import org.zkoss.zk.ui.util.ExecutionMonitor;
import org.zkoss.zk.ui.sys.SessionsCtrl;
import org.zkoss.zk.ui.sys.ExecutionCtrl;
import org.zkoss.zk.ui.sys.ExecutionsCtrl;
import org.zkoss.zk.ui.sys.DesktopCtrl;
import org.zkoss.zk.ui.sys.ComponentCtrl;
import org.zkoss.zk.ui.sys.EventProcessingThread;
/**
* A utility class that simplify the implementation of
* {@link org.zkoss.zk.ui.sys.EventProcessingThread}.
*
* @author tomyeh
*/
public class EventProcessor {
private static final Log log = Log.lookup(EventProcessor.class);
/** The desktop that the component belongs to. */
private final Desktop _desktop;
/** Part of the command: component to handle the event. */
private final Component _comp;
/** Part of the command: event to process. */
private Event _event;
/** Whether it is in processing an event.
* It is used only the event processing thread is disabled.
*/
private static ThreadLocal _inEvt;
/** Returns whether the current thread is an event listener.
*/
public static final boolean inEventListener() {
return (Thread.currentThread() instanceof EventProcessingThread)
|| (_inEvt != null && _inEvt.get() != null); //used if event thread is disabled
}
/** Sets whether the current thread is an event listener.
* It needs to be called only if the event processing thread is
* disabled.
*
* It is used only internally.
*/
/*package*/ static final void inEventListener(boolean in) {
if (in) {
if (_inEvt == null)
_inEvt = new ThreadLocal();
_inEvt.set(Boolean.TRUE);
} else {
if (_inEvt != null)
_inEvt.set(null);
}
}
/**
* @param comp the component. Its desktop must be either null
* or the same as desktop.
*/
public EventProcessor(Desktop desktop, Component comp, Event event) {
if (desktop == null || comp == null || event == null)
throw new IllegalArgumentException("null");
final Desktop dt = comp.getDesktop();
if (dt != null && desktop != dt)
throw new IllegalStateException("Process events for another desktop? "+comp);
_desktop = desktop;
_comp = comp;
_event = event;
}
/** Returns the desktop.
*/
public final Desktop getDesktop() {
return _desktop;
}
/** Returns the event.
*/
public final Event getEvent() {
return _event;
}
/** Returns the component.
*/
public final Component getComponent() {
return _comp;
}
/** Process the event.
* Note: it doesn't invoke EventThreadInit and EventThreadCleanup.
*
* This method is to implement
* {@link org.zkoss.zk.ui.sys.EventProcessingThread}.
* See also {@link org.zkoss.zk.ui.util.Configuration#isEventThreadEnabled}.
*/
public void process() throws Exception {
final ExecutionMonitor execmon =
_desktop.getWebApp().getConfiguration().getExecutionMonitor();
//Bug 1506712: event listeners might be zscript, so we have to
//keep built-in variables as long as possible
final Scope scope = Scopes.beforeInterpret(_comp);
//we have to push since process0 might invoke methods from zscript class
try {
Scopes.setImplicit("event", _event);
_event = ((DesktopCtrl)_desktop).beforeProcessEvent(_event);
if (_event != null) {
if (execmon != null)
execmon.eventStart(_event);
Scopes.setImplicit("event", _event); //_event might change
((ComponentCtrl)_comp).service(_event, scope);
((DesktopCtrl)_desktop).afterProcessEvent(_event);
}
} finally {
final Execution exec = _desktop.getExecution();
if (exec != null) //just in case
((ExecutionCtrl)exec).setExecutionInfo(null);
if (execmon != null &&_event != null)
execmon.eventComplete(_event);
Scopes.afterInterpret();
}
}
/** Setup this processor before processing the event by calling
* {@link #process}.
*
*
Note: it doesn't invoke {@link ExecutionCtrl#onActivate}
*/
public void setup() {
SessionsCtrl.setCurrent(_desktop.getSession());
final Execution exec = _desktop.getExecution();
ExecutionsCtrl.setCurrent(exec);
((ExecutionCtrl)exec).setCurrentPage(getPage());
}
/** Cleanup this process after processing the event by calling
* {@link #process}.
*
*
Note: Don't call this method if the event process executes
* in the same thread.
*/
public void cleanup() {
ExecutionsCtrl.setCurrent(null);
SessionsCtrl.setCurrent((Session)null);
}
private Page getPage() {
final Page page = _comp.getPage();
if (page != null)
return page;
return _desktop.getFirstPage();
}
//Object//
public String toString() {
return "[comp: "+_comp+", event: "+_event+']';
}
}