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Thread: How would you check for duplicate usernames in a file?

  1. #1
    Junior Member
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    Feb 2011
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    Default How would you check for duplicate usernames in a file?

    If I create a filename named users.txt that stores a list of usernames people would like to chose for an account, and I want to make sure their username is not already taken, how would I go about that?

    Thanks for the help

  2. #2
    Administrator copeg's Avatar
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    Oct 2009
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    Default Re: How would you check for duplicate usernames in a file?

    This question is extremely broad and open to many fine grained details...but if your looking for a good way to check for duplicate elements, use a Set. See The Set Interface (The Java™ Tutorials > Collections > Interfaces)

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