thoerup/schedulesamples/JavaTimer.java

/* using java.util.timer is the most simple but also very inflexible - and It is considered less-than-nice in relation to the app server since
 * it executes the scheduled task in a new background thread that the appserver has no control over.
 * 
 */

package dk.thoerup.schedulesamples;

import java.io.IOException;
import java.util.Calendar;
import java.util.Timer;
import java.util.TimerTask;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Servlet implementation class JavaTimer
 */
public class JavaTimer extends HttpServlet {
        private static final long serialVersionUID = 1L;
    
        class MyTask extends TimerTask {
                String str;
                int count = 0;
                
                public MyTask(String s) {
                        str = s;
                }
                
                @Override
                public void run() {
                        System.out.println("MyTask : " + str);
                        
                        count++;
                        if (count >=10)
                                this.cancel(); //cancel efter 10 runs                   
                }
        
                
        }
        
        Timer timer = new Timer();

        
        @Override
        public void destroy() {
                super.destroy();
                timer.cancel(); //remove all pending jobs
        }


        @Override
        protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
                //schedule a single run,, run after 3 seconds
                //timer.schedule(new MyTask("1"), 3000);
                
                
                //continuous execution first execution after 2 seconds and then with 1 second intervals
                //timer.schedule(new MyTask("2"), 2000, 1000);
                
                //schedule a single run at a specific time
                Calendar cal = Calendar.getInstance();
                cal.set(2010, 5, 1, 14, 40, 0); //months are zero indexed               
                timer.schedule(new MyTask("3"), cal.getTime() );                
                        
                response.getWriter().print("ok");
        }

}
1	/* using java.util.timer is the most simple but also very inflexible - and It is considered less-than-nice in relation to the app server since
2	* it executes the scheduled task in a new background thread that the appserver has no control over.
3	*
4	*/
5
6	package dk.thoerup.schedulesamples;
7
8	import java.io.IOException;
9	import java.util.Calendar;
10	import java.util.Timer;
11	import java.util.TimerTask;
12
13	import javax.servlet.ServletException;
14	import javax.servlet.http.HttpServlet;
15	import javax.servlet.http.HttpServletRequest;
16	import javax.servlet.http.HttpServletResponse;
17
18	/**
19	* Servlet implementation class JavaTimer
20	*/
21	public class JavaTimer extends HttpServlet {
22	private static final long serialVersionUID = 1L;
23
24	class MyTask extends TimerTask {
25	String str;
26	int count = 0;
27
28	public MyTask(String s) {
29	str = s;
30	}
31
32	@Override
33	public void run() {
34	System.out.println("MyTask : " + str);
35
36	count++;
37	if (count >=10)
38	this.cancel(); //cancel efter 10 runs
39	}
40
41
42	}
43
44	Timer timer = new Timer();
45
46
47
48	@Override
49	public void destroy() {
50	super.destroy();
51	timer.cancel(); //remove all pending jobs
52	}
53
54
55
56	@Override
57	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
58	//schedule a single run,, run after 3 seconds
59	//timer.schedule(new MyTask("1"), 3000);
60
61
62	//continuous execution first execution after 2 seconds and then with 1 second intervals
63	//timer.schedule(new MyTask("2"), 2000, 1000);
64
65	//schedule a single run at a specific time
66	Calendar cal = Calendar.getInstance();
67	cal.set(2010, 5, 1, 14, 40, 0); //months are zero indexed
68	timer.schedule(new MyTask("3"), cal.getTime() );
69
70	response.getWriter().print("ok");
71	}
72
73	}