What is wrong with opening and closing a stream like this?

Question

So I wrote some code and Netbeans suggests convert to try-with-resources on the same line I instantiate sc . This suggestion pops up the moment I put the sc.close() after the while-loop. I don't quite understand why this close-operation is badly placed.

        public static void main(String[] args)  {
         try{
             Scanner sc = new Scanner(new File(args[0]));
             while(sc.hasNext()){
                 System.out.println(sc.nextLine());
             }
             sc.close();

         } catch(FileNotFoundException e){
             System.out.println("Het bestand kon niet gevonden worden.");
         } catch(Exception e){
             System.out.println("Onbekende Fout");
         }
    }

Answer 1

The problem is that if anything inbetween the open and the close returns from the method or throws an exception then the close doesn't get called.

Using a try-with-resources (or pre Java 7 try-finally) to do the close guarantees that the stream gets closed every single time.