Timer Rescheduling problem

[Tom Keith]

Hi,

I have a problem in using Timer and TimerTask.

Problem:
I have a arraylist of say 100 codes. I have to loop through the arraylist and start individual process for each code. Then after eaach individual code is done, reschedule it back in 1 hour.

I am able to do the first part, but struck in the second part.

Code snippet:

 
public class CodeScheduler {
  RunTask task = null;
  Timer timer = new Timer(); // java.util.Timer
  for(int index = 0; index < codeList.size(); index++) {
    task = new RunTask((String)codeList.get(index), this);
    timer.schdeule(task, new Date(2000L));   
  }
  public void complete(RunTask task) {
     if(task != null) {
        task.cancel();
     }
  }
 
  class RunTask extends TimerTask { // java.util.TimerTask
      String strCode = null;
      CodeScheduler objCodeScheduler = null;
      public RunTask(String code, CodeScheduler cs) {
         strCode = code;
         objCodeScheduler = cs;
      }
      public void run() {
         do someting...
         objCodeScheduler.complete(this);
      }
  }
}

Can somebody tell me now how to schedule each code again after 1 hour?

Thanks to all in advance.

Thanks,
Tom


[HW: Added code tags]
[ September 16, 2006: Message edited by: Henry Wong ]

[Henry Wong]

Side question... Why are you calling the cancel() method on the timertask upon completion? If the task is *not* repetitive, it won't do anything as the current one is already running. But that leads to...

Repetitive tasks is exactly what you want. You can configure the timer to call the task every hour -- provided that you don't cancel it. See the JavaDoc for the overloaded schedule() methods.

Henry

[Tom Keith]

I tried another way of doing this and the following is the code:

import java.util.Date;
import java.util.TimeZone;
import java.util.Calendar;
import java.util.StringTokenizer;
import java.util.GregorianCalendar;
import java.text.SimpleDateFormat;
import java.text.ParsePosition;
import java.util.ArrayList;

public class TimerTest {

String arr[]={"element1", "element2"};
public static RunTask task = null;
public static int RETRY_COUNT = 4;
ArrayList arraylist = new ArrayList();
Date today, future;

public static void main(String[] args) {
new TimerTest();
}

public TimerTest() {
//Different ways to Add Elements to the arraylist
for(int i=0;i<arr.length;i++) {
arraylist.add(i,arr[i]);
}

String strCode = null;
try {
for(int i = 0;i< arraylist.size();i++) {
strCode = (String)arraylist.get(i);
task = new RunTask(strCode, RETRY_COUNT);
task.start();
System.out.println( "\n["+ Thread.currentThread().getName()+"] Started the thread ->" + task.getName());
System.out.println("Sleeping for 2 seconds...");
Thread.sleep(2000L);
}
}
catch(Exception e) {
}
}
}

class RunTask extends Thread {
String strCode = null;
RunTask task;
int iRetryCount = 0;

public RunTask(String code, int iCount) {
strCode = code;
iRetryCount = iCount;
}

public RunTask(String code, int iCount, RunTask rt) {
strCode = code;
task = rt;
iRetryCount = iCount;
}

public void run() {
try {
iRetryCount--;

if(task != null) {
System.out.println("Sleeping for 30 seconds...");
Thread.sleep(30000);
if(! task.isAlive()) {
System.out.println(Thread.currentThread().getName() + " is dead...");
}
}
// do someting

if(iRetryCount != 0) {
task = new RunTask(strCode, iRetryCount, this);
task.start();

System.out.println( "\n["+ Thread.currentThread().getName()+"] Stopped & terminated." +
"Starting thread ->" + task.getName());
}

Thread.sleep(1000L);
System.out.println(Thread.currentThread().getName() + " sleeping for 1 second...");

}
catch (ThreadDeath e) {
System.out.println(e.getMessage());
}
catch (Exception e) {
System.out.println(e.getMessage());
}
}
}

But, I have a question. I am killing the current Thread and creating another Thread and ask it to sleep for 30 seconds. This is just a simulation. My actual program will wait for 45 minutes.

My questionis, is there any other better way of doing it?

Thanks,
Tom