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Thread: what happens when you supply the same name of a nonexistent input file?

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    Smile what happens when you supply the same name of a nonexistent input file?

    i have a LineNumberer program that i wanna know what happens when i supply the name of a nonexistent input file to this program? does it just throw a FileNotFound exception?


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    Super Moderator helloworld922's Avatar
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    Default Re: what happens when you supply the same name of a nonexistent input file?

    Not necessarily. Files can hold any file/directory path whether they exist or don't. You can check if a file exists using the exists() method.

    File file = new File("garbage.txt");
    if (file.exists())
    {
         System.out.println("You have garbage on your computer!");
    }
    else
    {
         System.out.println("There is no garbage on your computer!");
    }

    However, if you try to open up a non-existent file for reading/writing, you will get a FileNotFoundException.

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    Default Re: what happens when you supply the same name of a nonexistent input file?

    Um, unless you are overwriting an existing file, it's normal to "open" a "nonexistent" file for writing by constructing a FileOutputStream etc. with the non-existent file as argument.

    Attempting to open a non-existent file for reading (is with an InputStream) will, as staed, throw an FNFE.

    db

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    Default Re: what happens when you supply the same name of a nonexistent input file?

    What happens when you supply the same name for the input and output files to the LineNumberer program?


    just trying to learn about writing data to files

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    Member Darryl.Burke's Avatar
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    Default Re: what happens when you supply the same name of a nonexistent input file?

    A better way to learn is to just try it and see for yourself, don't you think?

    db

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