New to Java

I am trying to insert a sleeper thread inbetween two actions in an else statement, here is my code:

else{
current.setBackground(Color.red);
last.setBackground(Color.red);
try {


Thread.sleep(4000);


} catch (InterruptedException ie)
{
System.out.println(ie.getMessage());
}


finally {

last.flipBack();
current.flipBack();
last.setEnabled(true);
current.setEnabled(true);
current.setBackground(null);
last.setBackground(null);
last=null;



}
}

Could someone tell me why the background changes above the try statement are being skipped, and how to fix it, or tell me of another way to put in a time delay. Thanks.