Question

I have a java scanner and two loops to handle user input, However it throws an NoSuchElement exception the second it hits the first loop with out asking for any input from the user.

Scanner Guess_input = new Scanner( System.in );


    while (guess > 0){
        failure = true;
        while(failure)
        {

            System.out.println("Please input");
            try
            {
                if (Guess_input.nextLine().length() == 1 && guesses.size() >= 1) {
                    guesses.add(Guess_input.nextLine());
                    System.out.println("You guessed" + guesses.get(guesses.size()) + "");
                }
                else if (Guess_input.nextLine().length() == 0) {
                    System.err.println("ERROR:");
                    Guess_input.nextLine();   //Clean Buffer
                    failure = true;
                }
                else 
                {
                    System.err.println("ERROR");
                    Guess_input.nextLine();   //Clean Buffer
                    failure = true;
                }
            }   
            catch(InputMismatchException ime)

            {
                System.err.println("error");
            }
            finally
            {
                Guess_input.close();
            }
        }
    }

Answer 1

From the java documentation, when using the next() method of the Scanner class, you’ll get

NoSuchElementException - if no such tokens are available

Whenever you call the nextLine() method, you are supposed to enter a String. You should first store the result of nextLine() in local variable unless that’s what you want.

Another problem is that your try catch finally is done in your while loop. It means that for each iteration, your finally bloc will be executed everytime, so you’ll think that there is an exception, while might be none. Apply these changes

try {
   while (guess > 0) {
       while (.....) {
           .....
       }
   }
} catch (...){
   ....
  }
finally{ .... }