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array sorting

Jini Varghese
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Joined: Dec 06, 2000
Posts: 58
How to sort an array in descending order ?
java.util.Arrays has methods that sorts in the ascending order. Do I have to use Comparator interface implementing the code for descending sort in its compare(), and pass the instance of the class that implements Comparator to sort() of Arrays class ?
Paul Anilprem
Enthuware Software Support
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Joined: Sep 23, 2000
Posts: 3254
    
    2
You do not have to implement the code for descending sort. It is already done by Arrays class. What you need to do is implement a Comparator object having compare method which just compares the two objects and return appropriate results ( ie. -1 when o1 is greater than o2 etc.) Pass this comparator object as the second parameter to the sort() method.
Or
Just implement compareTo() method in the class of objects that you want to sort. In this case you just have pass the array of objects.
Read Comparator, Arrays.sort() API for more details.
HTH,
Paul.
HTH,
Paul.
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Jini Varghese
Ranch Hand

Joined: Dec 06, 2000
Posts: 58
Thanks. It helped a lot...
 
It is sorta covered in the JavaRanch Style Guide.
 
subject: array sorting
 
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