BaseTimerTask getNextNotCancelledMin() {
BaseTimerTask e = getMin();
while (e != null && e.isCancelled()) {
removeMin();
cancelCount++;
e = getMin();
}
return e;
}
void fireTask(BaseTimerTask e) {
try {
boolean f = e.fire(e.getTime());
if (f) {
timer.eventsDelivered++;
} else {
cancelCount++;
}
} catch (Throwable ex) {
timer.fireExceptionCount++;
timer.log.warn("timer event caused exception", ex);
}
}
/**
* Cleans cancelled timer tasks from the priority queue. We do this just in the thread that calls
* us, but without holding up event delivery . When a purge occurs we work with two queues. One
* for added timer tasks and one for delivered timer tasks. Newly added timer tasks will be
* appended to the the out queue after the purge is finished. Thus, the delivery of new timer
* tasks is delayed after the purge is finished.
*
* <p>One tricky thing is to catch up with tasks that fired during the purge from the out queue.
* This is achieved by skipping to the time of the task that will fire next and by the ensurance
* that the timer thread will always process events of the same time within one synchronized
* block.
*/
void performPurge() {
Queue _purgeQ;
int _queueSizeBefore;
synchronized (lock) {
if (inQueue != outQueue || inQueue.size == 0) {
return;
}
addedWithoutPurge = Integer.MIN_VALUE;
cancelCount += inQueue.cancelCount;
outQueue.cancelCount = 0;
_purgeQ = outQueue.copy();
inQueue = new Queue();
_queueSizeBefore = outQueue.size;
}
_purgeQ.purge();
synchronized (lock) {
boolean _somethingFired = outQueue.size != _queueSizeBefore;
if (_somethingFired) {
BaseTimerTask _nextTimerTaskInQueue = outQueue.getNextNotCancelledMin();
if (_nextTimerTaskInQueue == null) {
cancelCount += outQueue.cancelCount;
_purgeQ = new Queue();
} else {
long _forwardUntilTime = _nextTimerTaskInQueue.getTime();
BaseTimerTask t;
BaseTimerTask _previousSkippedTask = null;
while ((t = _purgeQ.getMin()).getTime() != _forwardUntilTime) {
if (t.isCancelled()) {
_purgeQ.cancelCount++;
}
_purgeQ.removeMin();
_previousSkippedTask = t;
}
}
}
BaseTimerTask t;
while ((t = inQueue.getNextNotCancelledMin()) != null) {
inQueue.removeMin();
_purgeQ.addQueue(t);
}
cancelCount += inQueue.cancelCount;
inQueue = outQueue = _purgeQ;
addedWithoutPurge = 0;
if (inQueue.size > 0) {
startThread();
lock.notify();
}
purgeCount++;
}
}
int loop() {
long _fireTime;
long t = System.currentTimeMillis();
BaseTimerTask e;
int fireCnt = 0;
for (; ; ) {
boolean _fires;
synchronized (timer.lock) {
Queue q = timer.outQueue;
for (; ; ) {
e = q.getNextNotCancelledMin();
if (e == null) {
return fireCnt;
}
_fires = false;
_fireTime = e.getTime();
if (_fireTime > t) {
t = System.currentTimeMillis();
}
if (_fireTime <= t) {
if (_fireTime < t) { // missed timely execution?
recordLapse(_fireTime, t);
}
q.removeMin();
BaseTimerTask _next = q.getMin();
boolean _fireWithinLock = _next != null && _fireTime == _next.getTime();
if (_fireWithinLock) {
fireTask(e);
fireCnt++;
continue;
}
_fires = true;
}
break;
} // inner for loop
} // synchronized
if (_fires) {
fireTask(e);
fireCnt++;
} else {
long _waitTime = _fireTime - t;
waitUntilTimeout(_waitTime);
}
} // outer loop
}
