ScheduledThreadPoolExecutor, how stop runnable class JAVA

I have written the following code:

import java.util.Calendar;
import java.util.concurrent.ScheduledThreadPoolExecutor;
import java.util.concurrent.TimeUnit;

class Voter {   
public static void main(String[] args) {
    ScheduledThreadPoolExecutor stpe = new ScheduledThreadPoolExecutor(2);
    stpe.scheduleAtFixedRate(new Shoot(), 0, 1, TimeUnit.SECONDS);
}
}

class Shoot implements Runnable {
Calendar deadline;
long endTime,currentTime;

public Shoot() {
    deadline = Calendar.getInstance();
    deadline.set(2011,6,21,12,18,00);
    endTime = deadline.getTime().getTime();
}

public void work() {
    currentTime = System.currentTimeMillis();

    if (currentTime >= endTime) {
        System.out.println("Got it!");
        func();
    } 
}

public void run() {
    work();
}

public void func() {
    // function called when time matches
}
}

I would like to stop the ScheduledThreadPoolExecutor when the func() is called. There is no need for it to work futher! I think i should put the function func() inside Voter class, and than create some kind of callback. But maybe I can do it from within the Shoot class.

How can I solve it properly?