java - How to update jlabel while running animation? -

i have little animation rectangle, jlabel blue background, moving down screen. running thread this.

now, want have jlabel shows current position of rectangle.

public void run()  {      pnl.requestfocus();       x = (int) p.getx(); //find location of rectangle     y = (int) p.gety();      while (y < 450)      {         rectanglelabel.setlocation(x, y); //reset location of rectangle         y += 10;           try {                 thread.sleep(100);             }          catch (interruptedexception e)         {             }     }  } 

now want insert code inside while statement.

locationlabel.settext(string.valueof(450-y)); 

but every time do, jlable updates rectangle doesnt move anymore.

how go about?

try :

run example

   import javax.swing.*;    import java.lang.*;  class testthread extends jframe implements  runnable{  jlabel rectanglelabel,locationlabel; int x,y=0; testthread() {     setvisible(true);     setlayout(null);     rectanglelabel=new jlabel("rectangle");     rectanglelabel.setbounds(10,10,100,100);     locationlabel=new jlabel();     locationlabel.setbounds(200,200,100,100);     add(rectanglelabel);     add(locationlabel);      setsize(1000,1000);     thread t=new thread(this);     t.run();   }    public void run()   {   while (y < 450)  {     rectanglelabel.setlocation(x, y); //reset location of rectangle     y += 10;     locationlabel.settext(""+y);     try {             thread.sleep(100);         }      catch (interruptedexception e)     {     }     if(y==440)     {         y=0;      }    } }  public static void main(string args[]) {      testthread t=new testthread();   }    }