protected void _run() {
ConcurrentNavigableMap<Long, Entry>
head_map; // head_map = entries which are <= curr time (ready to be executed)
if (!(head_map = tasks.headMap(System.currentTimeMillis(), true)).isEmpty()) {
final List<Long> keys = new LinkedList<Long>();
for (Map.Entry<Long, Entry> entry : head_map.entrySet()) {
final Long key = entry.getKey();
final Entry val = entry.getValue();
pool.execute(
new Runnable() {
public void run() {
val.execute();
}
});
keys.add(key);
}
tasks.keySet().removeAll(keys);
}
if (tasks.isEmpty()) {
no_tasks.compareAndSet(false, true);
waitFor(); // sleeps until time elapses, or a task with a lower execution time is added
} else
waitUntilNextExecution(); // waits until next execution, or a task with a lower execution time
// is added
}
