Android uses handler to send requests every 5 seconds

    Handler handler = new Handler();

    Runnable runnable = new Runnable() {

        @Override
        public void run() {

            //要做的事情
            System.out.println("执行次数："+(++n)+"\n");
            handler.postDelayed(runnable, 5000);
        }
    };

call execution code

 handler.postDelayed(runnable, 5000);

It can also be implemented with Thread + Handler

    Handler handler = new Handler(new Handler.Callback() {
        @Override
        public boolean handleMessage(Message message) {

            int what = message.what;
            if(what == 1){
                String obj = (String) message.obj;
                System.out.println(obj);
            }

            return false;
        }
    });
    Thread thread = new Thread(new Runnable() {
        @Override
        public void run() {

            while (true){
                Message message = Message.obtain();
                message.what = 1;
                message.obj = "执行次数："+(++n);
                handler.sendMessage(message);
                //沉睡5秒
                try {
                    Thread.sleep(5000);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }
    });

start thread

 thread.start();