while (ltr.hasNext()) { Invoice next = (Invoice)ltr.next(); out.println(next.getPartNumber()+"\t"+next.getPartDis()+"\t"+next.getPrice()+"\t"+next.getQuanity());
while (ltr.hasNext()) { Invoice next = (Invoice)ltr.next(); out.println(next.getPartNumber()+"\t"+next.getPartDis()+"\t"+next.getPrice()+"\t"+next.getQuanity());