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Thread: Random Password

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    Question Random Password

    I'm a java beginner, i don't know english well. i do read tutorials, but i can't get all stuff about java. Now i'm trying to code a random pasword generator.. Rules :
    * maxlenght must be 8 characters
    * i can use only digits and lower cases.
    * three or more characters can't be the same.
    * the password must be different when i run the program again...

    Best Regards...


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    Default Re: Random Password

    Break it down into tasks:
    1. How to generate a random lowercase letter or digit.
    2. How to avoid more than 2 of the same character.
    3. How to stop when you have 8 characters.
    4. How to ensure the random selection is different each time you run it.

    Some tips: Before starting to write any code, figure out exactly how you plan to solve each of these problems. Make sure every step is worked out on paper in your native language before trying to translate it into Java. Designing an application and writing Java code are separate tasks, and each requires thought and care. Trying to do both at the same time will end in tears...

    There are two simple ways in the SDK to get a random number - the Math.random() method, which gives you a double (floating-point) random number, and the Random class, which has a bunch of methods for random numbers. There is another approach - you could shuffle a list of characters to randomize it. The Collections.shuffle(..) methods will shuffle a list.

    You also need to think about how to ensure you use no more than 2 of the same character - consider how you can check whether a character has already been used, and how to prevent it being selected again.

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    JavaPF (July 18th, 2011)

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    Default Re: Random Password

    i do know built an alghorithm but i can't use methots/functions... do need my program "shuffle" ?

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    Default Re: Random Password

    How you do it is up to you, but it might help to think of your set of possible password characters as a pack of cards, and consider how you could select 8 cards at random...

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    Default Re: Random Password

    use javascript to get the job done on the client side along with jsp......



    ashishkumar haldar.

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    Default Re: Random Password

    Quote Originally Posted by ashishkumar haldar View Post
    use javascript to get the job done on the client side along with jsp......



    ashishkumar haldar.
    I'm confused or maybe missed something. How does this apply to the original posters question?

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    Default Re: Random Password

    Quote Originally Posted by ashishkumar haldar View Post
    use javascript to get the job done on the client side along with jsp......



    ashishkumar haldar.
    I just know C n C++ how can i this job with javascript ?

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