public void show() {
beforeFirstShow = false;
if (!isModal()) {
conditionalShow(null, null);
} else {
// Set this variable before calling conditionalShow(). That
// way, if the Dialog is hidden right after being shown, we
// won't mistakenly block this thread.
keepBlocking = true;
// Store the app context on which this dialog is being shown.
// Event dispatch thread of this app context will be sleeping until
// we wake it by any event from hideAndDisposeHandler().
showAppContext = AppContext.getAppContext();
AtomicLong time = new AtomicLong();
Component predictedFocusOwner = null;
try {
predictedFocusOwner = getMostRecentFocusOwner();
if (conditionalShow(predictedFocusOwner, time)) {
// We have two mechanisms for blocking: 1. If we're on the
// EventDispatchThread, start a new event pump. 2. If we're
// on any other thread, call wait() on the treelock.
modalFilter = ModalEventFilter.createFilterForDialog(this);
final Runnable pumpEventsForFilter = new Runnable() {
public void run() {
EventDispatchThread dispatchThread =
(EventDispatchThread)Thread.currentThread();
dispatchThread.pumpEventsForFilter(new Conditional() {
public boolean evaluate() {
return keepBlocking && windowClosingException == null;
}
}, modalFilter);
}
};
// if this dialog is toolkit-modal, the filter should be added
// to all EDTs (for all AppContexts)
if (modalityType == ModalityType.TOOLKIT_MODAL) {
Iterator it = AppContext.getAppContexts().iterator();
while (it.hasNext()) {
AppContext appContext = (AppContext)it.next();
if (appContext == showAppContext) {
continue;
}
EventQueue eventQueue = (EventQueue)appContext.get(AppContext.EVENT_QUEUE_KEY);
// it may occur that EDT for appContext hasn't been started yet, so
// we post an empty invocation event to trigger EDT initialization
Runnable createEDT = new Runnable() {
public void run() {};
};
eventQueue.postEvent(new InvocationEvent(this, createEDT));
EventDispatchThread edt = eventQueue.getDispatchThread();
edt.addEventFilter(modalFilter);
}
}
modalityPushed();
try {
if (EventQueue.isDispatchThread()) {
/*
* dispose SequencedEvent we are dispatching on current
* AppContext, to prevent us from hang.
*
*/
// BugId 4531693 (son@sparc.spb.su)
SequencedEvent currentSequencedEvent = KeyboardFocusManager.
getCurrentKeyboardFocusManager().getCurrentSequencedEvent();
if (currentSequencedEvent != null) {
currentSequencedEvent.dispose();
}
/*
* Event processing is done inside doPrivileged block so that
* it wouldn't matter even if user code is on the stack
* Fix for BugId 6300270
*/
AccessController.doPrivileged(new PrivilegedAction() {
public Object run() {
pumpEventsForFilter.run();
return null;
}
});
} else {
synchronized (getTreeLock()) {
Toolkit.getEventQueue().postEvent(new PeerEvent(this,
pumpEventsForFilter,
PeerEvent.PRIORITY_EVENT));
while (keepBlocking && windowClosingException == null) {
try {
getTreeLock().wait();
} catch (InterruptedException e) {
break;
}
}
}
}
} finally {
modalityPopped();
}
// if this dialog is toolkit-modal, its filter must be removed
// from all EDTs (for all AppContexts)
if (modalityType == ModalityType.TOOLKIT_MODAL) {
Iterator it = AppContext.getAppContexts().iterator();
while (it.hasNext()) {
AppContext appContext = (AppContext)it.next();
if (appContext == showAppContext) {
continue;
}
EventQueue eventQueue = (EventQueue)appContext.get(AppContext.EVENT_QUEUE_KEY);
EventDispatchThread edt = eventQueue.getDispatchThread();
edt.removeEventFilter(modalFilter);
}
}
if (windowClosingException != null) {
windowClosingException.fillInStackTrace();
throw windowClosingException;
}
}
} finally {
if (predictedFocusOwner != null) {
// Restore normal key event dispatching
KeyboardFocusManager.getCurrentKeyboardFocusManager().
dequeueKeyEvents(time.get(), predictedFocusOwner);
}
}
}
}
Nicht nur JOptionPane macht das so, auch JDialog.
