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Scanner hasNext() and indexoutofboundsexception

David Delgado

Joined: Sep 19, 2010
Posts: 6
Hello everyone, I need some help here. So this program takes an input file that I will post at the bottom with ints.

Assignment: Write a program that inputs a list of numbers that are arranged into groups of various sizes. The program outputs the sum of the numbers in each group. Each group starts with a one-line descriptive phrase. The phrase can be anything that is not a number. Some groups may have zero number in them.

Problem: Everything runs fine at first and I get my first group sum of -44 which is correct but then i get this
I'm getting an StringIndexOutOfBoundsException String index out of range: 0 at java.lang.String.charAt(unknown source)

Input file:

Group A
Group B
Group C
Last Group

Solution should be:

Group 1
Sum = -44

Group 2
Sum = 5

Group 3
Sum = 0

Group 4
Sum = 108

Campbell Ritchie

Joined: Oct 13, 2005
Posts: 39396
Put some System.out.printf calls in for debugging. You may be getting a 0-length line. That is an obscure problem, which isn't well described in the books I have read. Ignore the rants, and have a look at what one of our more disreputable members said about that problem last year.
Sudipta Laha
Ranch Hand

Joined: Aug 23, 2010
Posts: 49

Try to give
scan.nextLine() once after
System.out.println("Group " + count + " equals " + sum);

check its working or not.. I believe you will be able to identity the error after that(line 27 if i am correct) and give the reason for that(as details given by Wouter).

Sudipta Kumar Laha
I agree. Here's the link:
subject: Scanner hasNext() and indexoutofboundsexception