title: --- in is already defined in main(java.lang.String[]) --- ERROR MESSAGE DRIVING ME MAD
body: <p>I'm a student starting out on my first programming module. The textbook I'm working from is 'Java for Everyone', Cay Horstmann. I'm on chapter 2.4 - Constants. I have copied and checked (over 15 times!) the code directly from the book, however every time I compile it produces the compile error <strong>in is already defined in main(java.lang.String[])</strong>. </p>
  
  <p>It highlights <strong>Scanner in = new Scanner(System.in);</strong> as being the problem. I have written another extremely simple program which also includes <strong>Scanner in = new Scanner(System.in);</strong> and I had exactly the same problem. </p>
  
  <p>I have tried to find the solution, I've reinstalled both Java JDK and BlueJ (compiler), but nothing has worked. I have Googled the problem, but I'm unable to find anything which matches my problem. I am a Java virgin, so to be honest it's pretty difficult to work out where I should be looking.</p>
  
  <p>Any help would be greatly appreciated. I'm behind a couple of weeks already, and this is holding my progress up considerably. </p>
  
  <p>Thanks, in advance, for any advice offered.</p>
  
  <p>All the best,</p>
  
  <p>Vicky</p>
  
  <pre><code>import java.util.Scanner;
  
  public class Volume2 
  {
  
      public static void main(String[] args)
      {
  
          final double BOTTLE_VOLUME = 2;  
          final double LITRES_PER_OUNCE = 0.0296; 
          final double CAN_VOLUME = 12 * LITRES_PER_OUNCE; 
  
          System.out.print("Please enter quantity of bottles: ");
  
          Scanner in = new Scanner(System.in);
  
          int bottles = in.nextInt();
  
          double totalVolume = totalVolume * BOTTLE_VOLUME;
  
          System.out.print("Please enter the number of cans: ");
  
          **Scanner in = new Scanner(System.in);** // This is highlighted as being the problem
  
          int cans = in.nextInt();
  
          double additionalVolume = cans * CAN_VOLUME;
  
          totalVolume = totalVolume + additionalVolume;
  
          System.out.print("The total volume is: ");
          System.out.println(totalVolume);
  
      }
  }
  </code></pre>
  
  <hr>
  
  <p>Error Message: <strong>in is already defined in main(java.lang.String[])</strong></p>
  
  <hr>