In Java, how do I execute code every X seconds?

Question

I'm making a really simple snake game, and I have an object called Apple which I want to move to a random position every X seconds. So my question is, what is the easiest way to execute this code every X seconds?

apple.x = rg.nextInt(470);
apple.y = rg.nextInt(470);

Thanks.

Edit:

Well do have a timer already like this:

Timer t = new Timer(10,this);
t.start();

What it does is draw my graphic elements when the game is started, it runs this code:

@Override
    public void actionPerformed(ActionEvent arg0) {
        Graphics g = this.getGraphics();
        Graphics e = this.getGraphics();
        g.setColor(Color.black);
        g.fillRect(0, 0, this.getWidth(), this.getHeight());
        e.fillRect(0, 0, this.getWidth(), this.getHeight());
        ep.drawApple(e);
        se.drawMe(g);

possible duplicate of [How to set a timer in java](http://stackoverflow.com/questions/4044726/how-to-set-a-timer-in-java) — Nim, Nov 23 '12 at 15:09
I do have a timer, I edited my question so you can see what it looks like. — Misoxeny, Nov 23 '12 at 15:14
http://www.ntu.edu.sg/home/ehchua/programming/java/J8d_Game_Framework.html — Sri Harsha Chilakapati, Nov 23 '12 at 15:34

score 8 · Answer 1 · answered Nov 23 '12 at 16:41

I would use an executor

ScheduledExecutorService scheduler = Executors.newScheduledThreadPool(1);
    Runnable toRun = new Runnable() {
        public void run() {
            System.out.println("your code...");
        }
    };
ScheduledFuture<?> handle = scheduler.scheduleAtFixedRate(toRun, 1, 1, TimeUnit.SECONDS);

score 2 · Answer 2 · edited Jun 17 '15 at 16:17

Use a timer:

Timer timer = new Timer();
int begin = 1000; //timer starts after 1 second.
int timeinterval = 10 * 1000; //timer executes every 10 seconds.
timer.scheduleAtFixedRate(new TimerTask() {
  @Override
  public void run() {
    //This code is executed at every interval defined by timeinterval (eg 10 seconds) 
   //And starts after x milliseconds defined by begin.
  }
},begin, timeinterval);

Documentation: Oracle documentation Timer

score 1 · Accepted Answer · edited Mar 31 '23 at 07:09

1

Simplest thing is to use Thread.sleep().

apple.x = rg.nextInt(470);
apple.y = rg.nextInt(470);
Thread.sleep(1000);

Run the above code in loop.

This will give you an approximate (may not be exact) one second delay.

edited Mar 31 '23 at 07:09

Oriol Roma

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answered Nov 23 '12 at 15:10

Yogendra Singh

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score 1 · Answer 4 · answered Nov 23 '12 at 15:23

You should have some sort of game loop which is responsible for processing the game. You can trigger code to be executed within this loop every x milliseconds like so:

while(gameLoopRunning) {
    if((System.currentTimeMillis() - lastExecution) >= 1000) {
        // Code to move apple goes here.

        lastExecution = System.currentTimeMillis();
    }
}

In this example, the condition in the if statement would evaluate to true every 1000 milliseconds.

In Java, how do I execute code every X seconds?

4 Answers4