| Methods Summary |
|---|
| final void | detachDispatchThread()
dispatchThread = null;
|
| protected void | dispatchEvent(java.awt.AWTEvent event)Dispatches an event. The manner in which the event is
dispatched depends upon the type of the event and the
type of the event's source object:
| Event Type |
Source Type |
Dispatched To |
| ActiveEvent |
Any |
event.dispatch() |
| Other |
Component |
source.dispatchEvent(AWTEvent) |
| Other |
MenuComponent |
source.dispatchEvent(AWTEvent) |
| Other |
Other |
No action (ignored) |
event.isPosted = true;
Object src = event.getSource();
if (event instanceof ActiveEvent) {
// This could become the sole method of dispatching in time.
setCurrentEventAndMostRecentTimeImpl(event);
((ActiveEvent)event).dispatch();
} else if (src instanceof Component) {
((Component)src).dispatchEvent(event);
event.dispatched();
} else if (src instanceof MenuComponent) {
((MenuComponent)src).dispatchEvent(event);
} else if (src instanceof AWTAutoShutdown) {
if (noEvents()) {
dispatchThread.stopDispatching();
}
} else {
System.err.println("unable to dispatch event: " + event);
}
|
| public static java.awt.AWTEvent | getCurrentEvent()Returns the the event currently being dispatched by the
EventQueue associated with the calling thread. This is
useful if a method needs access to the event, but was not designed to
receive a reference to it as an argument. Note that this method should
only be invoked from an application's event dispatching thread. If this
method is invoked from another thread, null will be returned.
return Toolkit.getEventQueue().getCurrentEventImpl();
|
| private synchronized java.awt.AWTEvent | getCurrentEventImpl()
return (Thread.currentThread() == dispatchThread)
? ((AWTEvent)currentEvent.get())
: null;
|
| final java.awt.EventDispatchThread | getDispatchThread()
return dispatchThread;
|
| public static long | getMostRecentEventTime()Returns the timestamp of the most recent event that had a timestamp, and
that was dispatched from the EventQueue associated with the
calling thread. If an event with a timestamp is currently being
dispatched, its timestamp will be returned. If no events have yet
been dispatched, the EventQueue's initialization time will be
returned instead.In the current version of
the JDK, only InputEvents,
ActionEvents, and InvocationEvents have
timestamps; however, future versions of the JDK may add timestamps to
additional event types. Note that this method should only be invoked
from an application's event dispatching thread. If this method is
invoked from another thread, the current system time (as reported by
System.currentTimeMillis()) will be returned instead.
return Toolkit.getEventQueue().getMostRecentEventTimeImpl();
|
| synchronized long | getMostRecentEventTimeEx()
return mostRecentEventTime;
|
| private synchronized long | getMostRecentEventTimeImpl()
return (Thread.currentThread() == dispatchThread)
? mostRecentEventTime
: System.currentTimeMillis();
|
| public java.awt.AWTEvent | getNextEvent()Removes an event from the EventQueue and
returns it. This method will block until an event has
been posted by another thread.
do {
/*
* SunToolkit.flushPendingEvents must be called outside
* of the synchronized block to avoid deadlock when
* event queues are nested with push()/pop().
*/
SunToolkit.flushPendingEvents();
synchronized (this) {
for (int i = NUM_PRIORITIES - 1; i >= 0; i--) {
if (queues[i].head != null) {
EventQueueItem eqi = queues[i].head;
queues[i].head = eqi.next;
if (eqi.next == null) {
queues[i].tail = null;
}
return eqi.event;
}
}
AWTAutoShutdown.getInstance().notifyThreadFree(dispatchThread);
wait();
}
} while(true);
|
| java.awt.AWTEvent | getNextEvent(int id)
do {
/*
* SunToolkit.flushPendingEvents must be called outside
* of the synchronized block to avoid deadlock when
* event queues are nested with push()/pop().
*/
SunToolkit.flushPendingEvents();
synchronized (this) {
for (int i = 0; i < NUM_PRIORITIES; i++) {
for (EventQueueItem entry = queues[i].head, prev = null;
entry != null; prev = entry, entry = entry.next)
{
if (entry.id == id) {
if (prev == null) {
queues[i].head = entry.next;
} else {
prev.next = entry.next;
}
if (queues[i].tail == entry) {
queues[i].tail = prev;
}
return entry.event;
}
}
}
this.waitForID = id;
wait();
this.waitForID = 0;
}
} while(true);
|
| final void | initDispatchThread()
synchronized (this) {
if (dispatchThread == null && !threadGroup.isDestroyed()) {
dispatchThread = (EventDispatchThread)
AccessController.doPrivileged(new PrivilegedAction() {
public Object run() {
EventDispatchThread t =
new EventDispatchThread(threadGroup,
name,
EventQueue.this);
t.setContextClassLoader(classLoader);
t.setPriority(Thread.NORM_PRIORITY + 1);
t.setDaemon(false);
return t;
}
});
AWTAutoShutdown.getInstance().notifyThreadBusy(dispatchThread);
dispatchThread.start();
}
}
|
| public static void | invokeAndWait(java.lang.Runnable runnable)Causes runnable to have its run
method called in the dispatch thread of the EventQueue.
This will happen after all pending events are processed.
The call blocks until this has happened. This method
will throw an Error if called from the event dispatcher thread.
if (EventQueue.isDispatchThread()) {
throw new Error("Cannot call invokeAndWait from the event dispatcher thread");
}
class AWTInvocationLock {}
Object lock = new AWTInvocationLock();
InvocationEvent event =
new InvocationEvent(Toolkit.getDefaultToolkit(), runnable, lock,
true);
synchronized (lock) {
Toolkit.getEventQueue().postEvent(event);
lock.wait();
}
Throwable eventThrowable = event.getThrowable();
if (eventThrowable != null) {
throw new InvocationTargetException(eventThrowable);
}
|
| public static void | invokeLater(java.lang.Runnable runnable)Causes runnable to have its run
method called in the dispatch thread of the EventQueue.
This will happen after all pending events are processed.
Toolkit.getEventQueue().postEvent(
new InvocationEvent(Toolkit.getDefaultToolkit(), runnable));
|
| public static boolean | isDispatchThread()Returns true if the calling thread is the current AWT
EventQueue's dispatch thread. Use this
call the ensure that a given
task is being executed (or not being) on the current AWT
EventDispatchThread.
EventQueue eq = Toolkit.getEventQueue();
EventQueue next = eq.nextQueue;
while (next != null) {
eq = next;
next = eq.nextQueue;
}
return (Thread.currentThread() == eq.dispatchThread);
|
| private static synchronized int | nextThreadNum()
return threadInitNumber++;
|
| private boolean | noEvents()Returns whether an event is pending on any of the separate
Queues.
for (int i = 0; i < NUM_PRIORITIES; i++) {
if (queues[i].head != null) {
return false;
}
}
return true;
|
| public synchronized java.awt.AWTEvent | peekEvent(int id)Returns the first event with the specified id, if any.
for (int i = NUM_PRIORITIES - 1; i >= 0; i--) {
EventQueueItem q = queues[i].head;
for (; q != null; q = q.next) {
if (q.id == id) {
return q.event;
}
}
}
return null;
|
| public synchronized java.awt.AWTEvent | peekEvent()Returns the first event on the EventQueue
without removing it.
for (int i = NUM_PRIORITIES - 1; i >= 0; i--) {
if (queues[i].head != null) {
return queues[i].head.event;
}
}
return null;
|
| protected void | pop()Stops dispatching events using this EventQueue.
Any pending events are transferred to the previous
EventQueue for processing.
Warning: To avoid deadlock, do not declare this method
synchronized in a subclass.
if (debug) {
System.out.println("EventQueue.pop(" + this + ")");
}
// To prevent deadlock, we lock on the previous EventQueue before
// this one. This uses the same locking order as everything else
// in EventQueue.java, so deadlock isn't possible.
EventQueue prev = previousQueue;
synchronized ((prev != null) ? prev : this) {
synchronized(this) {
if (nextQueue != null) {
nextQueue.pop();
return;
}
if (previousQueue == null) {
throw new EmptyStackException();
}
// Transfer all events back to previous EventQueue.
previousQueue.nextQueue = null;
while (peekEvent() != null) {
try {
previousQueue.postEventPrivate(getNextEvent());
} catch (InterruptedException ie) {
if (debug) {
System.err.println("interrupted pop:");
ie.printStackTrace(System.err);
}
}
}
AppContext appContext = AppContext.getAppContext();
if (appContext.get(AppContext.EVENT_QUEUE_KEY) == this) {
appContext.put(AppContext.EVENT_QUEUE_KEY, previousQueue);
}
previousQueue = null;
}
}
EventDispatchThread dt = this.dispatchThread;
if (dt != null) {
dt.stopDispatching(); // Must be done outside synchronized
// block to avoid possible deadlock
}
|
| public void | postEvent(java.awt.AWTEvent theEvent)Posts a 1.1-style event to the EventQueue.
If there is an existing event on the queue with the same ID
and event source, the source Component's
coalesceEvents method will be called.
SunToolkit.flushPendingEvents();
postEventPrivate(theEvent);
|
| private void | postEvent(java.awt.AWTEvent theEvent, int priority)Posts the event to the internal Queue of specified priority,
coalescing as appropriate.
if (dispatchThread == null) {
if (theEvent.getSource() == AWTAutoShutdown.getInstance()) {
return;
} else {
initDispatchThread();
}
}
Object source = theEvent.getSource();
// Expanding RepaintArea
if (source instanceof Component) {
ComponentPeer sourcePeer = ((Component)source).peer;
if (sourcePeer != null && theEvent instanceof PaintEvent &&
!(sourcePeer instanceof LightweightPeer)) {
sourcePeer.coalescePaintEvent((PaintEvent)theEvent);
}
}
EventQueueItem newItem = new EventQueueItem(theEvent);
boolean notifyID = (theEvent.getID() == this.waitForID);
if (queues[priority].head == null) {
boolean shouldNotify = noEvents();
queues[priority].head = queues[priority].tail = newItem;
if (shouldNotify) {
if (theEvent.getSource() != AWTAutoShutdown.getInstance()) {
AWTAutoShutdown.getInstance().notifyThreadBusy(dispatchThread);
}
notifyAll();
} else if (notifyID) {
notifyAll();
}
} else {
boolean isPeerEvent = theEvent instanceof PeerEvent;
// For Component source events, traverse the entire list,
// trying to coalesce events
if (source instanceof Component) {
EventQueueItem q = queues[priority].head;
if (theEvent.id == Event.MOUSE_MOVE ||
theEvent.id == Event.MOUSE_DRAG) {
EventQueueItem qm;
for(qm = q; qm != null; qm = qm.next) {
if ((qm.event instanceof MouseEvent) &&
qm.id != theEvent.id) {
q = qm;
}
}
}
for (; q != null; q = q.next) {
// Give Component.coalesceEvents a chance
if (q.event.getSource() == source && q.id == newItem.id) {
AWTEvent coalescedEvent = ((Component)source).coalesceEvents(q.event, theEvent);
if (isPeerEvent && coalescedEvent == null && q.event instanceof PeerEvent) {
coalescedEvent = ((PeerEvent)q.event).coalesceEvents((PeerEvent)theEvent);
}
if (coalescedEvent != null) {
// Remove debugging statement because
// calling AWTEvent.toString here causes a
// deadlock.
q.event = coalescedEvent;
return;
}
}
}
}
// The event was not coalesced or has non-Component source.
// Insert it at the end of the appropriate Queue.
queues[priority].tail.next = newItem;
queues[priority].tail = newItem;
if (notifyID) {
notifyAll();
}
}
|
| final void | postEventPrivate(java.awt.AWTEvent theEvent)Posts a 1.1-style event to the EventQueue.
If there is an existing event on the queue with the same ID
and event source, the source Component's
coalesceEvents method will be called.
theEvent.isPosted = true;
synchronized(this) {
int id = theEvent.getID();
if (nextQueue != null) {
// Forward event to top of EventQueue stack.
nextQueue.postEventPrivate(theEvent);
} else if (theEvent instanceof PeerEvent &&
(((PeerEvent)theEvent).getFlags() &
PeerEvent.ULTIMATE_PRIORITY_EVENT) != 0) {
postEvent(theEvent, ULTIMATE_PRIORITY);
} else if (theEvent instanceof PeerEvent &&
(((PeerEvent)theEvent).getFlags() &
PeerEvent.PRIORITY_EVENT) != 0) {
postEvent(theEvent, HIGH_PRIORITY);
} else if (id == PaintEvent.PAINT ||
id == PaintEvent.UPDATE) {
postEvent(theEvent, LOW_PRIORITY);
} else {
postEvent(theEvent, NORM_PRIORITY);
}
}
|
| public synchronized void | push(java.awt.EventQueue newEventQueue)Replaces the existing EventQueue with the specified one.
Any pending events are transferred to the new EventQueue
for processing by it.
if (debug) {
System.out.println("EventQueue.push(" + newEventQueue + ")");
}
if (nextQueue != null) {
nextQueue.push(newEventQueue);
return;
}
synchronized (newEventQueue) {
// Transfer all events forward to new EventQueue.
while (peekEvent() != null) {
try {
newEventQueue.postEventPrivate(getNextEvent());
} catch (InterruptedException ie) {
if (debug) {
System.err.println("interrupted push:");
ie.printStackTrace(System.err);
}
}
}
newEventQueue.previousQueue = this;
}
/*
* Stop the event dispatch thread associated with the currently
* active event queue, so that after the new queue is pushed
* on the top this event dispatch thread won't prevent AWT from
* being automatically shut down.
* Use stopDispatchingLater() to avoid deadlock: stopDispatching()
* waits for the dispatch thread to exit, so if the dispatch
* thread attempts to synchronize on this EventQueue object
* it will never exit since we already hold this lock.
*/
if (dispatchThread != null) {
dispatchThread.stopDispatchingLater();
}
nextQueue = newEventQueue;
AppContext appContext = AppContext.getAppContext();
if (appContext.get(AppContext.EVENT_QUEUE_KEY) == this) {
appContext.put(AppContext.EVENT_QUEUE_KEY, newEventQueue);
}
|
| final void | removeSourceEvents(java.lang.Object source, boolean removeAllEvents)
SunToolkit.flushPendingEvents();
synchronized (this) {
for (int i = 0; i < NUM_PRIORITIES; i++) {
EventQueueItem entry = queues[i].head;
EventQueueItem prev = null;
while (entry != null) {
if ((entry.event.getSource() == source)
&& (removeAllEvents
|| ! (entry.event instanceof SequencedEvent
|| entry.event instanceof SentEvent
|| entry.event instanceof FocusEvent
|| entry.event instanceof WindowEvent
|| entry.event instanceof KeyEvent
|| entry.event instanceof InputMethodEvent)))
{
if (entry.event instanceof SequencedEvent) {
((SequencedEvent)entry.event).dispose();
}
if (entry.event instanceof SentEvent) {
((SentEvent)entry.event).dispose();
}
if (prev == null) {
queues[i].head = entry.next;
} else {
prev.next = entry.next;
}
} else {
prev = entry;
}
entry = entry.next;
}
queues[i].tail = prev;
}
}
|
| static void | setCurrentEventAndMostRecentTime(java.awt.AWTEvent e)
Toolkit.getEventQueue().setCurrentEventAndMostRecentTimeImpl(e);
|
| private synchronized void | setCurrentEventAndMostRecentTimeImpl(java.awt.AWTEvent e)
if (Thread.currentThread() != dispatchThread) {
return;
}
currentEvent = new WeakReference(e);
// This series of 'instanceof' checks should be replaced with a
// polymorphic type (for example, an interface which declares a
// getWhen() method). However, this would require us to make such
// a type public, or to place it in sun.awt. Both of these approaches
// have been frowned upon. So for now, we hack.
//
// In tiger, we will probably give timestamps to all events, so this
// will no longer be an issue.
if (e instanceof InputEvent) {
InputEvent ie = (InputEvent)e;
mostRecentEventTime = ie.getWhen();
} else if (e instanceof InputMethodEvent) {
InputMethodEvent ime = (InputMethodEvent)e;
mostRecentEventTime = ime.getWhen();
} else if (e instanceof ActionEvent) {
ActionEvent ae = (ActionEvent)e;
mostRecentEventTime = ae.getWhen();
} else if (e instanceof InvocationEvent) {
InvocationEvent ie = (InvocationEvent)e;
mostRecentEventTime = ie.getWhen();
}
|
| private void | wakeup(boolean isShutdown)
synchronized(this) {
if (nextQueue != null) {
// Forward call to the top of EventQueue stack.
nextQueue.wakeup(isShutdown);
} else if (dispatchThread != null) {
notifyAll();
} else if (!isShutdown) {
initDispatchThread();
}
}
|
