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Need help with creating a random array.

Thomas Mullane
Greenhorn

Joined: Jan 29, 2012
Posts: 3
So first I had to create an insert method to place tracks into an array.. Got that easy enough.. Next I have to randomly mix up that array... Can get some of that but my last track is being duplicated a lot of the time.. I heed help to stop this! Here is my code!





list is the original array that the tracks were inserted into.
entryCount is the list length.
Stephan van Hulst
Bartender

Joined: Sep 20, 2010
Posts: 3378
    
    9
Hi Thomas,

Why don't you just use Lists instead of arrays? You will also be able to simply use the Collections.shuffle() method.
Jesper de Jong
Java Cowboy
Saloon Keeper

Joined: Aug 16, 2005
Posts: 13875
    
  10

The standard Java library already has a method to shuffle a List: Collections.shuffle(list). If you need to shuffle an array, you can use Arrays.asList(array) to wrap the array as a list.

So to shuffle your array of Track objects you could just do:

If you need to implement this yourself (for example because it's homework and you're supposed to implement it yourself), see Fisher–Yates shuffle for an explanation of a good and simple shuffling algorithm.


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