Difference between calling stop from applet menu and restart in appletviewer

Question

 i have an animation program using threads and applet.

when i call stop option from applet menu in appletviewer program works normally but when i press restart there is some abnormality in its working. Thread does not come out of the while loop on calling restart at line no.34

   class saver
    {
    .


     .
        public void run()
        {
        System.out.println("run "+Thread.currentThread().getName());
         func();
        System.out.println("out of synchronized block");
        }
        synchronized public void func()
        {
        int i;
        while(running)
        {
        for(i=0;i<4;i++)
        {
        gap[i]+=10;
        if(gap[i]==360)
        gap[i]=0;
        System.out.println(Thread.currentThread().getName());
        calc(gap[i],400,i%2==0?(byte)1:(byte)-1);
        yb[i]=(int)(y)+yc;
        xb[i]=(int)(x)+xc;
      }
        repaint();
         try                   
          {                 
           Thread.sleep(1000);          
         }              
        catch(Exception e)
        {}
         }
         System.out.println("out of while in synchronized block");//not being printed
        }