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    <p>The problem is in your <code>enterGradeNames()</code> method with:</p> <pre><code>input.next() </code></pre> <p>You have to first call <code>input.hasNext()</code>;</p> <p>From <a href="http://docs.oracle.com/javase/7/docs/api/java/util/Scanner.html#next%28%29" rel="nofollow noreferrer">documentation</a>:</p> <blockquote> <p>Throws: NoSuchElementException - if no more tokens are available.</p> </blockquote> <p><strong>EDIT:</strong> as per comments</p> <p>I am unable to reproduce the problem, but there are many unnecessary lines in your code, so try running this edited code and see whether it changes anything.</p> <pre><code>public class Grades { private int len; private String [] gradeNames; private int [] gradeArray; private int enterGradeNames(){ Scanner input = new Scanner(System.in); for (int i = 0; i &lt; len; i++){ System.out.println("Enter the type of grades you will be reporting: (" + (i + 1) + " of " + gradeArray.length + ")" ); gradeNames[i] = new String(input.next()); } return 0; } public Grades(int length){ this.len = length; gradeArray = new int[len]; gradeNames = new String[len]; } </code></pre> <p>It's not generally good choice to call non-static methods inside constructor as the object isn't finished yet. You could do this in a (factory) method instead:</p> <pre><code>public static Grades buildGrades(){ Scanner s = new Scanner(System.in); System.out.println("Enter size:"); int size = s.nextInt(); Grades grades = new Grades(size); grades.enterGradeNames(); return grades; } </code></pre> <p><strong>EDIT2:</strong></p> <p>I searched a bit and the problem might be with your closing of the <code>Scanner</code>. Because if you call close on the <code>Scanner</code>, it will look whether its stream implements <code>Closeable</code> and if so it will close it as well. I never thought <code>System.in</code> would be closeable, but <em>it is</em>.</p> <p>So the best option? Possibly use one <code>Scanner</code> for the whole program OR just don't close it if you dont want its stream to be closed. More can be read <a href="https://stackoverflow.com/questions/14142853/close-a-scanner-linked-to-system-in?lq=1">here</a>.</p>
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    1. COyeah, comments to "go check the documentation" are usually not useful as you can't assume someone hasn't. Whats more helpful is assistance in interpreting the meaning of the documentation. I still don't understand why checking "hasNext" which seemingly returns a bool is going to make my scanner suddenly work.
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    2. CO@gjnave it's not going to make it work. I though the documentation makes it clear enough.. hasNext tells you whether there is some token (string, int, ..) which can be returned. But if hasNext() returns false, it means there is no token, hence you shouldn't be calling the next() method, if you will then it must throw an Exception, because there is no element.
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    3. COok so heres the crux of the problem -besides that our teacher has explained none of this - (thank you for your reply), there is no token to return --- all that I understand about the class is that you call the "next..." method to input and the user inputs something. So, what do you do if there is no token to return? (i have googled this to no joy btw)
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