code: public void clear() {
  	assertEDT();
  	log.debug("[clear] Cleaning board");
  	for (int row = 0; row < SIZE; row++) {
  	    for (int col = 0; col < SIZE; col++) {
  		removeItem(new Point(col, row));
  	    }
  	}
      }
docs: Removes all the drawn elements