Threads in vector

I have 3 classes.

//Task.class as follow
import java.util.*;
import java.io.*;
import java.text.*;

public class Task extends Thread {
     boolean live = true;
     long sleepInterval;
     int cc = 0;
     public static Task Instance;
     public Task() {
          Instance = this;
          sleepInterval = 5000;
          start();
     }
     
     public void run() {
     
          while (live) {
               try {
                    sleep(sleepInterval);
               } catch (Exception e) {
                    System.out.println("Interrupted sleep:loadsubmit " + e);
                    }
          }
     }

     public void setSleepInterval()
     {
          this.interrupt();
          sleepInterval = 10000;
     }

     public void printText() {
          System.out.println("thread is alive " + this.isAlive());
     }
}

//END

2. UpdateTask.class will extends Thread and call Task.Instance.setSleepInterval to update the sleepInterval for specific Task.
2. Main.class contain a vector to add a numbers of Task.class.
My answer is how can i refer UpdateTask to the specific Task.Instance because every Task.class has the same Instance name (Task).

Thanks alot.