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Message:

Random Algorithm Shuffling - The Easy Way!

Posted by Matt Gerrans on November 09, 2001 at 12:13 AM

Duh. As I was out on my bike ride today, it occurred to me that Java does have a method for sorting Lists in the API. I had a vague impression that I had seen a list somewhere that had it already, but I thought it was Python, because when I looked at the List interface in my Java docs, there was no shuffle(). Java's does have it, though, it is just a little trickier to find because it is a static method of Collections, rather than a method of List, or one of its implementations. So all the previous example code could be reduced to Collections.shuffle(itemList); (assuming you want to use the default source of randomness to randomly permute your list).

- mfg

• biking Chin Long November 09, 2001 at 3:05 AM (4)
  • Weather Cycles Matt Gerrans November 09, 2001 at 3:40 AM (3)
    • hmmm Chin Loong November 10, 2001 at 5:42 AM (2)
      • hmmm (continued) Chin Loong November 10, 2001 at 5:46 AM (1)
        • oh geez Chin Loong November 10, 2001 at 5:57 AM (0)