StringTokenizer / NullPointerException problem

I have been getting a NullPointerException during this specific section in my application. I assume that the StringTokenizer is grabbing a null value which is causing the problem, but it is my understanding that the hasMoreTokens() method should eliminate that problem. The input file that I use is a .csv file.

public String ipScrub(String replacement)
    {
        String scrubbed = null;
        try
        {
            File file = new File("classcodes.csv");
            FileReader fileReader = new FileReader(file);
            BufferedReader reader = new BufferedReader(fileReader);
            StringTokenizer parser;
            String line = null;
            String check = null;
            int num;
            do
            {
                line = reader.readLine();
                parser = new StringTokenizer(line, ",");
                {
                    check = parser.nextToken();
                    if (check.equals(replacement))
                    {
                        scrubbed = parser.nextToken();
                        check = null;
                    }
                    else
                    {
                        System.out.println("No match!");
                        check = null;
                    }
                }
                System.out.println("Exited For Loop");
            }
            while (parser.hasMoreTokens());
            reader.close();
            System.out.println("Reader closing...");
        }
        catch(Exception ex)
        {
            ex.printStackTrace();
        }
 
        if (scrubbed == null)
        {
            scrubbed = "X.X";
        }
        
        return scrubbed;
    }

This is the error.

You don't call hasMoreTokens until you have made at least one call to nextToken.
But what I think your problem really is, is that you don't check if 'line' is null before passing it to StringTokenizer.

What I'll do is add a string like EOF on the end of my classcodes file and use that as a delimiter for the end of the file. This is a little cludgy, but it will at least narrow the focus.

line will be set to null when you reach the end of the file so why don't you use that to end your while loop
Try