/*
* returns true if this thread can obtain the global lock or already has the lock;
* otherwise this loader and thread are added to the waitingList
*/
private static synchronized boolean tryLock(Thread currentThread, Object loader) {
if (lockThread == currentThread) {
lockCount++;
return true;
}
if (lockThread == null) {
lockCount++;
lockThread = currentThread;
return true;
}
waitingList.add(new Object[] {currentThread, loader});
return false;
}
/*
* unlocks the global lock and notifies the first waiting thread that they
* now have the lock
*/
private static void unlock() {
Thread waitingThread = null;
Object loader = null;
synchronized (BundleLoader.class) {
lockCount--;
if (lockCount != 0) return;
if (waitingList.isEmpty()) {
lockThread = null;
return;
}
Object[] waiting = (Object[]) waitingList.get(0);
waitingThread = (Thread) waiting[0];
loader = waiting[1];
}
synchronized (loader) {
synchronized (BundleLoader.class) {
lockThread = waitingThread;
waitingList.remove(0);
loader.notifyAll();
}
}
}
