请看这个演示:

import java.util.Timer;
import java.util.TimerTask;

class Test {
     public static void main( String [] args ) {
          int delay = 5000;// in ms 

          Timer timer = new Timer();

          timer.schedule( new TimerTask(){
             public void run() { 
                 System.out.println("Wait, what..:");
              }
           }, delay);

           System.out.println("Would it run?");
     }
}

使用CountDownTimer非常简单。 详情https://developer.android.com/reference/android/os/CountDownTimer.html

import android.os.CountDownTimer;

// calls onTick every second, finishes after 3 seconds
new CountDownTimer(3000, 1000) { 

   public void onTick(long millisUntilFinished) {
      Log.d("log", millisUntilFinished / 1000);
   }

   public void onFinish() {
      // called after count down is finished
   } 
}.start();

Kotlin & Java多种方式

1. 使用处理程序

Handler().postDelayed({
    TODO("Do something")
    }, 2000)

2. 使用TimerTask

Timer().schedule(object : TimerTask() {
    override fun run() {
        TODO("Do something")
    }
}, 2000)

或者更短

Timer().schedule(timerTask {
    TODO("Do something")
}, 2000)

或者说最短的是

Timer().schedule(2000) {
    TODO("Do something")
}

3.使用执行人

Executors.newSingleThreadScheduledExecutor().schedule({
    TODO("Do something")
}, 2, TimeUnit.SECONDS)

在Java中

1. 使用处理程序

new Handler().postDelayed(new Runnable() {
    @Override
    public void run() {
        //Do something
    }
}, 2000);

2. 使用定时器

new Timer().schedule(new TimerTask() {          
    @Override
    public void run() {
        // Do something
    }
}, 2000);

3.使用ScheduledExecutorService

private static final ScheduledExecutorService worker = Executors.newSingleThreadScheduledExecutor();

Runnable runnable = new Runnable() {
  public void run() {
      // Do something
  }
  };
worker.schedule(runnable, 2, TimeUnit.SECONDS);

好吧，如果你使用Java，你总是可以使用遗留的Thread.sleep()。

new Thread(() -> {

    try {
        Thread.sleep(millis); //delay in milliseconds
    } catch (Exception e) {
        e.printStackTrace();
    }

    yourMethod();

}).start();

这里唯一的问题是你不能做任何UI更新，因为它是一个单独的线程。

final Handler handler = new Handler(); 
Timer t = new Timer(); 
t.schedule(new TimerTask() { 
    public void run() { 
        handler.post(new Runnable() { 
            public void run() { 
                //DO SOME ACTIONS HERE , THIS ACTIONS WILL WILL EXECUTE AFTER 5 SECONDS...
            }
        }); 
    } 
}, 5000); 

如果你使用RxAndroid，那么线程和错误处理就会变得容易得多。以下代码在延迟后执行

Observable.timer(delay, TimeUnit.SECONDS)
        .subscribeOn(Schedulers.io())
        .observeOn(AndroidSchedulers.mainThread())
        .subscribe(aLong -> {
            // Execute code here
        }, Throwable::printStackTrace);