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Thread: How to sort an ArrayList of Strings?

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    Default How to sort an ArrayList of Strings?

    I want to make different type of sort. I have an ArrayList of Strings. When the information is shown I want all the Strings beginning with "blablabla" to be shown first. How can I achieve that?


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    Super Moderator Norm's Avatar
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    Default Re: How to sort an ArrayList of Strings?

    Look at the Collections class. It has sort methods you can use. You'll need your own code to determine the sort order.

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    Default Re: How to sort an ArrayList of Strings?

    Try to look at Comparator and Comparable interfaces. You have to implement one of these or both interfaces, implement some methods and then sort the method by calling Collections.sort() or something. I can't tell exactly how it goes because I haven't done that for a long time, but the idea should be clear to you. Try to look for some examples with these interfaces.
    Last edited by Asido; September 15th, 2010 at 04:33 AM.

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    Default Re: How to sort an ArrayList of Strings?

    Quote Originally Posted by Asido View Post
    Try to look at Comparator and Comparable interfaces. You have to implement one of these or both interfaces
    String already implements Comparable.

    db

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    Super Moderator Norm's Avatar
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    Default Re: How to sort an ArrayList of Strings?

    Strings beginning with "blablabla" to be shown first
    That will require the OP to use his own code to set the order.

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    Default Re: How to sort an ArrayList of Strings?

    Quote Originally Posted by Darryl.Burke View Post
    String already implements Comparable.

    db
    In this case just override the method compareTo()

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    Default Re: How to sort an ArrayList of Strings?

    Quote Originally Posted by Asido View Post
    In this case just override the method compareTo()
    String is final cannot be extended, so its methods cannot be overridden. The Comparable interface must be implemented in some other way.

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