por ejemplo
private ScheduledExecutorService scheduler;
private AccurateScheduledRunnable periodic;
private ScheduledFuture<?> periodicMonitor;
private int taskPeriod = 30;
private SimpleDateFormat sdf = new SimpleDateFormat("dd.MM.yyyy HH:mm:ss");
private SimpleDateFormat sdfHour = new SimpleDateFormat("HH");
. . .
scheduler = Executors.newSingleThreadScheduledExecutor();
periodic = new AccurateScheduledRunnable() {
private final int ALLOWED_TARDINESS = 200;
private int countRun = 0;
private int countCalled = 0;
@Override
public void run() {
countCalled++;
if (this.getExecutionTime() < ALLOWED_TARDINESS) {
countRun++;
dateNext = new java.util.Date();
dateLast = new java.util.Date();
long tme = dateNext.getTime();
tme += (taskPeriod * 60) * 1000;
dateNext.setTime(tme);
//System.out.println("");
//System.out.println("");
//System.out.println("Next Sheduled Time at : " + sdf.format(dateNext));
//System.out.println("Periodic Cycle In : " + (countRun) + "/" + countCalled + " at " + sdf.format(dateLast));
//ti.displayMessage(null, " Running Sheduled Task at " + sdf.format(new Date()), TrayIcon.MessageType.NONE);
distAppInfo();
}
}
};
periodicMonitor = scheduler.scheduleAtFixedRate(periodic, 0, taskPeriod, TimeUnit.MINUTES);
periodic.setThreadMonitor(periodicMonitor);
e implementa Monitor que devuelve f.e. el tiempo restante hasta el siguiente Shedule
long she = periodicMonitor.getDelay(TimeUnit.SECONDS);
y Monitor
abstract class AccurateScheduledRunnable implements Runnable {
private ScheduledFuture<?> thisThreadsMonitor;
public void setThreadMonitor(ScheduledFuture<?> monitor) {
this.thisThreadsMonitor = monitor;
}
protected long getExecutionTime() {
long delay = -1 * thisThreadsMonitor.getDelay(TimeUnit.MILLISECONDS);
return delay;
}
}