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Thread: How do you check to see if a RandomAccessFile already exists?

  1. #1
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    Default How do you check to see if a RandomAccessFile already exists?

    I'm asking the user to give me the name of the file they wish to write to. If that file already exists, I will ask them if they wish to update that file, or just create a different file with a different name. If the file doesn't exist, I just create the file right there.

    This was working well through the ".exists()" method of the File class, but apparently RandomAccessFiles can't do that??

    I looked the API for the RAF and nowhere have I found anything that resembles ".exists()".

    Here's my code:
    System.out.println("What is the name of the file you would like to write to?");
            public RandomAccessFile receiveFile ()
            {
                    String fileName;
                    String yesno = "y";
                    RandomAccessFile raf = null;
                    Scanner input = new Scanner(System.in);
     
                    do
                    {
                            System.out.println("What is the name of the file you would like to write to?");
                            fileName = input.next();
     
                            try
                            {
                                    raf = new RandomAccessFile(fileName, "rw");
     
                            } catch (IOException ex)
                            {
                                    System.out.println();
                            }
     
                            // check if file already exists
                            if(raf.exists()) // ERROR THIS DOESN'T WORK
                            {
                                    System.out.println("That file already exists. Would you like to update it? (y/n)");
                                    yesno = input.next();
                            }
     
                    } while (yesno.equals("n"));
     
                    return raf;
            }


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    Default Re: How do you check to see if a RandomAccessFile already exists?

    But you can still use the user-specified filename as a File, determine if it exists, etc., and then create the RandomAccessFile using the constructor that takes a File as an argument. Won't that work?

  3. The Following User Says Thank You to GregBrannon For This Useful Post:

    ineedahero (November 2nd, 2013)

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    Default Re: How do you check to see if a RandomAccessFile already exists?

    Well that works! Haha, thanks.

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