Delayed Background Thread Runnable

With Java 1.5, if you want a function to execute at a certain time in the future, it is no longer necessary to create timers and callbacks. Java 1.5 has a ExecutorService that can execute tasks at scheduled times. Below shows a quick example of how it can be used.

package drills;

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;

public class Tester {

  DateFormat _df;

  public Tester() {
    _df = new SimpleDateFormat("yyyyMMdd HH:mm:ss");
  }

  public String GetTimeNow() {
    Date dt = new Date();
    return _df.format(dt);
  }

  public void RunTest() {
    Runnable worker = new Runnable() {
      public void run() {
        System.out.format("%s: Worker running\n", GetTimeNow());                
      }
    };

    ScheduledExecutorService ex = Executors.newSingleThreadScheduledExecutor();
    System.out.format("%s: Scheduled worker to run in 5 seconds\n", GetTimeNow());
    ex.schedule(worker, 5, TimeUnit.SECONDS);

    try {
      Thread.sleep(10000);
    } catch(Exception e) {
      // Even if interrupted exception is thrown during sleep, keep going
    }
    System.out.println("Test completed");
  } 

  public static void main(String[] args) {
    Tester t = new Tester();
    t.RunTest();
  }
}

The test app output looks like this:

20140317 23:56:53: Scheduled worker to run in 5 seconds
20140317 23:56:58: Worker running
Test completed