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Thread: renaming/deleting file

  1. #1
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    Default renaming/deleting file

    Hi again, I now have a problem where I rename a file, and delete another one, and neither one of the actions are actually happening.

    It looks like this:
    static File rfile = new File(dir + "points.txt");
    File rfile4 = new File(dir + "temp.txt");
    rfile4.renameTo(rfile);
    		          System.out.println(rfile4);
    		          rfile.delete();

    I have nothing happening after this, yet when I go to check if anything happened, both files are still there, and neither have been renamed. To prove it, the data that I entered into rflie4 before renaming it is still there (and the file is called "temp"). The System.out.println statement returns "C:\Users\John\workspace\Various classes\temp.txt" when it should return "C:\Users\John\workspace\Various classes\points.txt."

  2. The Following User Says Thank You to The_Mexican For This Useful Post:

    javapenguin (January 14th, 2011)


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    Default Re: renaming/deleting file

    how did you define dir variable? try also to remove the "static" keyword.
    Last edited by JavaHater; January 9th, 2011 at 07:05 PM.

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    Default Re: renaming/deleting file

    renameTo(File dest) returns a boolean that indicates whether the rename operation was successful or not. I would recommend checking this return value to determine what behavior you should expect.

    From the javadoc:

    Many aspects of the behavior of this method are inherently platform-dependent: The rename operation might not be able to move a file from one filesystem to another, it might not be atomic, and it might not succeed if a file with the destination abstract pathname already exists. The return value should always be checked to make sure that the rename operation was successful.

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    Default Re: renaming/deleting file

    Quote Originally Posted by DavidFongs View Post
    renameTo(File dest) returns a boolean that indicates whether the rename operation was successful or not. I would recommend checking this return value to determine what behavior you should expect.

    From the javadoc:
    Ok, so I checked the return value and saw that they both came up as false. But now is there a way I could make it work? Does renameTo() just not work if there's always a file by that name?

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    Default Re: renaming/deleting file

    Quote Originally Posted by JavaHater View Post
    how did you define dir variable? try also to remove the "static" keyword.
    dir is basically where the program is running from. I can't remove the static because I was taking these lines somewhat out of context, there is a reason I need the static there.

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    Super Moderator copeg's Avatar
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    Default Re: renaming/deleting file

    Given DavidFong's post above noting the platform dependence of this function and the behavior you noted, there is always the ugly option of doing it the brute-force way (open and read the file, create/write a new file with the new name and write the contents, finally deleting the old file).

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    Default Re: renaming/deleting file

    From your original post, its obvious you are using Windows to do this. On a windows system, what you are trying to do will fail if a file already exists with the name you want to rename the temp file to. The operation will also fail if the source file that you are trying to rename doesn't exist (but that isn't your issue here).

    Since you are renaming rfile4 to rfile (effectively overwriting rfile) why not just call rfile.delete() before the rename call

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    Default Re: renaming/deleting file

    Quote Originally Posted by DavidFongs View Post
    From your original post, its obvious you are using Windows to do this. On a windows system, what you are trying to do will fail if a file already exists with the name you want to rename the temp file to. The operation will also fail if the source file that you are trying to rename doesn't exist (but that isn't your issue here).

    Since you are renaming rfile4 to rfile (effectively overwriting rfile) why not just call rfile.delete() before the rename call
    I tried what you suggested but it still came up as false and nothing happened It guess the only way this will work is doing what copeg suggested?

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    Default Re: renaming/deleting file

    1. What OS are you running under? With Windows Vista/7, certain areas require elevated privileges in order to modify (such as the Program Files folder).
    2. Do the original file and the new file both exist according to Java? Check using rfile4.exists() and rfile.exists().

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    Default Re: renaming/deleting file

    Quote Originally Posted by helloworld922 View Post
    1. What OS are you running under? With Windows Vista/7, certain areas require elevated privileges in order to modify (such as the Program Files folder).
    2. Do the original file and the new file both exist according to Java? Check using rfile4.exists() and rfile.exists().
    1. Windows Vista. I seriously doubt I would need elevated privileges in order to delete these text files. I've tried deleting them manually and it works.

    2. Yes, I checked using the way you suggested.

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    Default Re: renaming/deleting file

    Hmm... I'm not entirely sure what's going on. Perhaps it's an issue with your installed software? What version of the JDK and JRE do you have? The latest JDK/JRE is Java SE 6 update 23.

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    Default Re: renaming/deleting file

    Quote Originally Posted by helloworld922 View Post
    Hmm... I'm not entirely sure what's going on. Perhaps it's an issue with your installed software? What version of the JDK and JRE do you have? The latest JDK/JRE is Java SE 6 update 23.
    I have Java SE 6 Update 21. I guess I'll update it to 23 but I doubt that's the problem...

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    Default Re: renaming/deleting file

    it was a slim chance

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    Default Re: renaming/deleting file

    Well I guess I'll just do it the manual way copeg suggested. Thanks anyway guys!

    EDIT: Ah yes! I partly figured it out! Ok, so what needed to happen is that I had to delete/rename the files after I closed the FileInputStream, which I wasn't doing before. However, there is still a small problem. I can only either delete one or rename the other. For example, if I delete rfile first then I can't rename rfile4. If I rename rfile4 first then I can't delete rfile. Any ideas on how I should do this?
    Last edited by The_Mexican; January 12th, 2011 at 11:58 AM.

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    Cool Re: renaming/deleting file

    Hmmmmm....file has a method called renameTo(File dest).

    If you're renaming it, it's going somewhere else in memory.

    File also has a method called delete().

    I don't see why you can't do one or the other?

    Why would you rename it and then delete it right away for anyway?

    If you called renameTo and then called delete in the same place you're doing this operation, it should be able to do both. Have to look at the code to know more.
    Also, any idea how to update JDK to 6.23 so that I can use AWTUtilities?

    And why were you printing out a File?

    Did you mean to print out

    file.getName() instead?



    You could post the entire code. There might be something going wrong outside of what you've shown. *

    Also, I've added stars to your ratings, as this is a good thread, and it'll also attract more attention I think as it'll stand out.
    Last edited by javapenguin; January 14th, 2011 at 11:24 PM.

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    Default Re: renaming/deleting file

    This might also be a long shot, but why is one of your File objects static and the other isn't?

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