/**
* Dequeue the oldest object on the queue. Used only by the run() method.
*
* @return the oldest object on the queue.
* @exception java.lang.InterruptedException if any thread has interrupted this thread.
*/
private synchronized QueueElement dequeue() throws InterruptedException {
while (tail == null) wait();
QueueElement elt = tail;
tail = elt.prev;
if (tail == null) {
head = null;
} else {
tail.next = null;
}
elt.prev = elt.next = null;
return elt;
}
/**
* Enqueue an event.
*
* @param event Either a <tt>NamingExceptionEvent</tt> or a subclass of <tt>NamingEvent</tt> or
* <tt>UnsolicitedNotificatoniEvent</tt>. If it is a subclass of <tt>NamingEvent</tt>, all
* listeners must implement the corresponding subinterface of <tt>NamingListener</tt>. For
* example, for a <tt>ObjectAddedEvent</tt>, all listeners <em>must</em> implement the
* <tt>ObjectAddedListener</tt> interface. <em>The current implementation does not check this
* before dispatching the event.</em> If the event is a <tt>NamingExceptionEvent</tt>, then
* all listeners are notified.
* @param vector List of NamingListeners that will be notified of event.
*/
synchronized void enqueue(EventObject event, Vector vector) {
QueueElement newElt = new QueueElement(event, vector);
if (head == null) {
head = newElt;
tail = newElt;
} else {
newElt.next = head;
head.prev = newElt;
head = newElt;
}
notify();
}