在Java中使用文件io创建一个高分

Question

I have been attempting to create a highscore with file.io but have not been able to do it. This is the code I have.

public void highScore ()
{
    int highScore = 0;
    String line = "";
    try
    {
        BufferedReader reader = new BufferedReader (new FileReader ("highScores"));
        while ((line = reader.readLine ()) != null)                 // read the score file line by line
        {
            try
            {
                int score = Integer.parseInt (line); // parse each line as an int
                if (score > highScore)                       // and keep track of the largest
                {
                    highScore = score;
                }
            }
            catch (NumberFormatException e1)
            {
                // ignore invalid scores
                //System.err.println("ignoring invalid score: " + line);
            }
            line = reader.readLine ();
        }
        reader.close ();

    }
    catch (IOException ex)
    {
        System.err.println ("ERROR reading scores from file");
    }
    c.println (highScore);
}

My text file has only numbers in it in each line

Answer 1

I guess you get:

"ERROR reading scores from file"

You should fix your filename extension:

BufferedReader reader = new BufferedReader (new FileReader ("highScores.txt"));

and make sure the file lies in the project's folder.

Also, notice you read two lines from the file each time, at the end of the while loop and in the while header, so delete line = reader.readLine (); at the end of the loop.

Answer 2

As a side note the best practice would be catching Exception . Right now you are just trying to catch IOException , do something like

catch(Exception e){
   e.printStackTrace();
}

As Exception is super class of all exceptions you can see if the code is breaking because of some other exception (in this case it might be FileNotFoundException )

and printing the stack tarce will help you point out the issue with line number in the code where exactly you are getting an exception.