Implementing a timer in java

Question

My situation is, I have two concurrent threads, one that cant start a timer and the other can stop the timer. The timer works in a way such that, once it has started it will count to 5 seconds and execute a function after, it will keep doing this until the timer is stopped by the other thread. How can this be implemented in Java. This is what I have, I feel it is the wrong way of doing it:

Note that sleep is a global volatile variable that the other two threads turn on and off.

            void creatTime(final EventHandler handler)
            {
                Thread timer = new Thread()
                {
                    public void run()
                    {
                        try
                        {
                            while(true)
                            {
                                while(sleep) Thread.sleep(1000);

                                //invoke function

                            }
                        }
                        catch(IOException e)
                        {
                            System.out.println(e);
                        }
                    }
                };
                timer.start();
            }
            }

Well, I don't see anybody assigning the sleep Boolean any value. — GingerHead
– GingerHead, Commented Nov 6, 2012 at 6:48
@Harutyun yes, I haven't posted all the code, its long, but its just simple, switching that is synchronized. — Mike G
– Mike G, Commented Nov 6, 2012 at 6:49
@ShashankKadne so that the while condition is continuously being checked — Mike G
– Mike G, Commented Nov 6, 2012 at 6:51
So what's wrong with using java.util.Timer or a ScheduledService? — MadProgrammer
– MadProgrammer, Commented Nov 6, 2012 at 6:53

Shashank Kadne · Accepted Answer · 2012-11-06 06:56:19Z

4

You can create a TimerTask and schedule it to run every 5 seconds

TimerTask timerTask = new TimerTask() {

            @Override
            public void run() {
                // TODO Auto-generated method stub
                //Invoke your function here
            }
        };

//Create a Timer and schedule it

Timer timer = new Timer();

timer.scheduleAtFixedRate(timerTask, 0, 5*1000);

//To terminate the Timer you can call its cancel method.

answered Nov 6, 2012 at 6:56

Shashank Kadne

8,1017 gold badges43 silver badges54 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Patricia Shanahan · Accepted Answer · 2012-11-06 13:43:50Z

2

I agree with the TimerTask recommendation. In general, the more of your thread-related work you can pass on to the higher level features of java.util.concurrent etc. the better. For example, the original code does not deal with early wake-ups from sleep.

In addition, if the sleep variable remains after redesign, it needs to be marked volatile or accessed through synchronized get and set methods. There is a limited set of activities that ensure that writes done in one thread must become visible to reads done in another thread.

answered Nov 6, 2012 at 13:43

Patricia Shanahan

26.2k4 gold badges42 silver badges75 bronze badges

Collectives™ on Stack Overflow

Implementing a timer in java

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related