ScheduledExecutorService with variable delay

Question

Suppose I have a task that is pulling elements from a java.util.concurrent.BlockingQueue and processing them.

public void scheduleTask(int delay, TimeUnit ti         


        

Answer 1

I had to do this recently using ScheduledFuture and didn't want to wrap Runnable or such. Here's how I did it:

private ScheduledExecutorService scheduleExecutor;
private ScheduledFuture scheduleManager;
private Runnable timeTask;

public void changeScheduleTime(int timeSeconds){
    //change to hourly update
    if (scheduleManager!= null)
    {
        scheduleManager.cancel(true);
    }
    scheduleManager = scheduleExecutor.scheduleAtFixedRate(timeTask, timeSeconds, timeSeconds, TimeUnit.SECONDS);
}

public void someInitMethod() {

    scheduleExecutor = Executors.newScheduledThreadPool(1);    
    timeTask = new Runnable() {
        public void run() {
            //task code here
            //then check if we need to update task time
            if(checkBoxHour.isChecked()){
                changeScheduleTime(3600);
            }
        }
    };

    //instantiate with default time
    scheduleManager = scheduleExecutor.scheduleAtFixedRate(timeTask, 60, 60, TimeUnit.SECONDS);
}