title: Incompatible type error between scanner.next() and String
body: <p>I am trying to compile this block of code, and it is telling me that <code>in.next()</code> in the while loop is not compatible with <code>String</code>, but I thought the <code>next()</code> method returns a <code>String</code>?</p>
  
  <p>I have import statements for <code>Scanner</code> class and <code>java.io</code></p>
  
  <pre><code>public static void main ( String[] args){
      Scanner in = new Scanner(new File(args[0]));
      while ( in.hasNext()){
          in = stringReverse(in.next());
      }
  }
  
  public static String stringReverse ( String s ) {...}
  </code></pre>