Package org.zkoss.zk.ui.impl

Class UiEngineImpl

  • All Implemented Interfaces:
    UiEngine
    public class UiEngineImpl
extends java.lang.Object
implements UiEngine
    An implementation of UiEngine to create and update components.
    Author:
    tomyeh

    • Constructor Detail

      • UiEngineImpl

        public UiEngineImpl()

    • Method Detail

      • start

        public void start​(WebApp wapp)
        Description copied from interface: UiEngine
        Starts the engine.
        Specified by:
        start in interface UiEngine

      • stop

        public void stop​(WebApp wapp)
        Description copied from interface: UiEngine
        Stops the engine. Called only if the server is about to stop.
        Specified by:
        stop in interface UiEngine

      • hasSuspendedThread

        public boolean hasSuspendedThread()
        Description copied from interface: UiEngine
        Returns if any suspended event processing thread in the whole system.
        Specified by:
        hasSuspendedThread in interface UiEngine

      • getSuspendedThreads

        public java.util.Collection<EventProcessingThread> getSuspendedThreads​(Desktop desktop)
        Description copied from interface: UiEngine
        Returns a collection of suspended event processing threads belonging to the specified desktop, or empty if no suspended thread at all.

        An event processing thread is an instance of EventProcessingThread

        Specified by:
        getSuspendedThreads in interface UiEngine
        Parameters:
        desktop - the desktop that the suspended event processing threads belong to (never null).

      • ceaseSuspendedThread

        public boolean ceaseSuspendedThread​(Desktop desktop,
                                    EventProcessingThread evtthd,
                                    java.lang.String cause)
        Description copied from interface: UiEngine
        Ceases the specified event thread.
        Specified by:
        ceaseSuspendedThread in interface UiEngine
        Parameters:
        desktop - which desktop the event thread belongs to
        cause - an arbitrary text to describe the cause. It will be the message of the thrown InterruptedException.
        Returns:
        true if the event processing thread is ceased successfully; false if no such thread or it is not suspended.

      • desktopDestroyed

        public void desktopDestroyed​(Desktop desktop)
        Description copied from interface: UiEngine
        Called when a desktop is being removed.

        Application developers don't need to remove pages and desktops. They are removed and cleaned up automatically.

        Specified by:
        desktopDestroyed in interface UiEngine

      • setOwner

        public Component setOwner​(Component comp)
        Description copied from interface: UiEngine
        Called before a component redraws itself if the component might include another page.

        If a new page is created, the specified component will become the owner of the new page.

        It must reset the owner in the finally clause. 

        old = ue.setOwner(this);
try{
  ...
} finally {
  ue.setOwner(old);
}

        Since 5.0.6, the owner must implement Includer.

        Specified by:
        setOwner in interface UiEngine
        Returns:
        the previous owner

      • isInvalidated

        public boolean isInvalidated​(Component comp)
        Description copied from interface: UiEngine
        Returns if this component needs to be redrawn.

        Note:

        1. It always returns true if the current execution is not an asynchronous update.
        2. If its parent is invalidated, this component will be redrawn too, but this method returns false since UiEngine.addInvalidate(Component) was not called against this component.
        Specified by:
        isInvalidated in interface UiEngine

      • addInvalidate

        public void addInvalidate​(Page page)
        Description copied from interface: UiEngine
        Invalidates the page to cause all of its components to redraw.
        Specified by:
        addInvalidate in interface UiEngine

      • addSmartUpdate

        public void addSmartUpdate​(Component comp,
                           java.lang.String attr,
                           java.lang.Object value,
                           boolean append)
        Description copied from interface: UiEngine
        Smart-updates a property of the peer widget.
        Specified by:
        addSmartUpdate in interface UiEngine
        append - whether to append the updates of properties with the same name. If false, only the last value of the same property will be sent to the client.

      • addSmartUpdate

        public void addSmartUpdate​(Component comp,
                           java.lang.String attr,
                           java.lang.Object value,
                           int priority)
        Description copied from interface: UiEngine
        Adds a smart update that will be executed at the given priority. The higher priority, the earlier the update is executed. If UiEngine.addSmartUpdate(Component, String, Object, boolean) is invoked, the priority is assumed to 0.

        If the priority is the same, the update is executed in the order of first-in-first out. You rarely need to control the sequence, unless the update is used to instantiate client-side widgets that other updates might depend on. In this case, it is suggested to specify the priority as 10000 (and not to use priority higher than 10000 for other situation).

        Specified by:
        addSmartUpdate in interface UiEngine

      • clearSmartUpdate

        public void clearSmartUpdate​(Component comp)
        Description copied from interface: UiEngine
        Clears all existing smart updates that belong to the given component.
        Specified by:
        clearSmartUpdate in interface UiEngine

      • addMoved

        public void addMoved​(Component comp,
                     Component oldparent,
                     Page oldpg,
                     Page newpg)
        Description copied from interface: UiEngine
        Called to update (redraw) a component, when a component is moved. If a component's page or parent is changed, this method need to be called only once for the top one.
        Specified by:
        addMoved in interface UiEngine
        oldparent - the parent before moved
        oldpg - the page before moved
        newpg - the page after moved

      • addUuidChanged

        public void addUuidChanged​(Component comp)
        Description copied from interface: UiEngine
        Called before changing the component's UUID.
        Specified by:
        addUuidChanged in interface UiEngine

      • disableClientUpdate

        public boolean disableClientUpdate​(Component comp,
                                   boolean disable)
        Description copied from interface: UiEngine
        Sets whether to disable the update of the client widget. By default, if a component is attached to a page, modifications that change the visual representation will be sent to the client to ensure the consistency.
        Specified by:
        disableClientUpdate in interface UiEngine
        Returns:
        whether it has been disabled before this invocation, i.e., the previous disable status

      • execNewPage

        public void execNewPage​(Execution exec,
                        PageDefinition pagedef,
                        Page page,
                        java.io.Writer out)
                 throws java.io.IOException
        Description copied from interface: UiEngine
        Creates components specified in the given page definition. Called when a new page is creates.
        Specified by:
        execNewPage in interface UiEngine
        Throws:
        java.io.IOException

      • recycleDesktop

        public void recycleDesktop​(Execution exec,
                           Page page,
                           java.io.Writer out)
                    throws java.io.IOException
        Description copied from interface: UiEngine
        Reuse the desktop and generate the output.
        Specified by:
        recycleDesktop in interface UiEngine
        Throws:
        java.io.IOException

      • afterRenderComponents

        protected void afterRenderComponents​(java.util.Collection<Component> comps)
        Called when this engine renders the given components.
        Parameters:
        comps - the collection of components that have been redrawn.

      • sendRedirect

        public void sendRedirect​(java.lang.String uri,
                         java.lang.String target)
        Description copied from interface: UiEngine
        Sends a temporary redirect response to the client using the specified redirect location URL.

        After calling this method, the caller shall end the processing immediately (by returning). All pending requests and events will be dropped.

        Specified by:
        sendRedirect in interface UiEngine
        Parameters:
        uri - the URI to redirect to, or null to reload the same page
        target - the new target, or null to denote the same browser window

      • setAbortingReason

        public void setAbortingReason​(AbortingReason aborting)
        Description copied from interface: UiEngine
        Aborts the current execution. if not null, it means the current execution is aborting

        Note: if setAbortingReason is ever set with non-null, you CANNOT set it back to null.

        After call this method, you shall not keep processing the page because the rendering is dropped and the client is out-of-sync with the server.

        Specified by:
        setAbortingReason in interface UiEngine
        Parameters:
        aborting - the aborting reason.

      • beginUpdate

        public void beginUpdate​(Execution exec)
        Description copied from interface: UiEngine
        Activates and prepare for asynchronous update
        Specified by:
        beginUpdate in interface UiEngine

      • endUpdate

        public void endUpdate​(Execution exec)
               throws java.io.IOException
        Description copied from interface: UiEngine
        Executes posted events, deactivate and ends the asynchronous update.
        Specified by:
        endUpdate in interface UiEngine
        Throws:
        java.io.IOException

      • execUpdate

        public void execUpdate​(Execution exec,
                       java.util.List<AuRequest> requests,
                       AuWriter out)
                throws java.io.IOException
        Description copied from interface: UiEngine
        Executes an asynchronous update to a component (or page). It is the same as execUpdate(exec, requests, null, out).

        Note: the output must be XML and UTF-8.

        Specified by:
        execUpdate in interface UiEngine
        requests - a list of AuRequest.
        Throws:
        java.io.IOException

      • notify

        public void notify​(Desktop desktop,
                   java.lang.Object mutex)
        Description copied from interface: UiEngine
        Wakes up a single event processing thread for the specified desktop that is waiting on the specified object.

        Unlike UiEngine.notify(Object), this method can be called any time. It is designed to let working threads resume an event processing thread.

        Notice: if this method is NOT called in an event processing thread, the resumed thread won't execute until the next request is received. To enforce it happen, you might use the timer component (found in ZUL).

        Specified by:
        notify in interface UiEngine
        Parameters:
        desktop - the desktop which the suspended thread is processing. It must be the same desktop of the suspended thread.
        mutex - any non-null object to identify what to notify. It must be same object passed to UiEngine.wait(java.lang.Object).
        See Also:
        UiEngine.notify(Object), UiEngine.notifyAll(Desktop, Object)

      • notifyAll

        public void notifyAll​(Desktop desktop,
                      java.lang.Object mutex)
        Description copied from interface: UiEngine
        Wakes up all event processing threads for the specified desktop that are waiting on the specified object.

        Unlike UiEngine.notifyAll(Object), this method can be called any time. It is designed to let working threads resume an event processing thread.

        If this method is NOT called in an event processing thread, the resumed thread won't execute until the next request is received. To enforce it happen, you might use the timer component (found in ZUL).

        Specified by:
        notifyAll in interface UiEngine
        Parameters:
        desktop - the desktop which the suspended thread is processing. It must be the same desktop of the suspended thread.
        mutex - any non-null object to identify what to notify. It must be same object passed to UiEngine.wait(java.lang.Object).
        See Also:
        UiEngine.notify(Object), UiEngine.notifyAll(Desktop, Object)

      • activate

        public boolean activate​(Execution exec,
                        int timeout)
        Description copied from interface: UiEngine
        Activates an execution such that you can access a component. Unlike UiEngine.activate(Execution), you could specify an amount of time (timeout), and it returns false if it takes longer than the given amount of time before granted.
        Specified by:
        activate in interface UiEngine
        timeout - the number of milliseconds to wait before giving up. It is ignored if negative, i.e., it waits until granted if negative.
        Returns:
        whether the activation succeeds

      • deactivate

        public void deactivate​(Execution exec)
        Description copied from interface: UiEngine
        Deactivates an execution, such that other threads could activate and access components.
        Specified by:
        deactivate in interface UiEngine

      • getNativeContent

        public java.lang.String getNativeContent​(Component comp,
                                         java.util.List<NodeInfo> children,
                                         Native.Helper helper)
        Description copied from interface: UiEngine
        Retrieve the native content for a property of the specified component. The native content is a value of a property that is represented by a XML fragment (actually NativeInfo).

        Example: 

        <html>
 <attribute name="content">
  <br/>
 </attribute>
</html>
        Specified by:
        getNativeContent in interface UiEngine
        Parameters:
        comp - the component that the native content will be assigned to. It is the object that the self variable is assigned when evaluating EL expressions.
        children - a list of NativeInfo, TextInfo and others. This method evaluates them one-by-one and returns the result which is the value that will be assigned.
        helper - the helper used to generate the content.
        See Also:
        Property