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Shravan Durvasula

Joined: Mar 06, 2004
Posts: 19
Why is it that the following code does not run?

Thanks in advance,
Fletcher Estes
Ranch Hand

Joined: Jul 01, 2004
Posts: 108
Hi Shravan,

A TreeSet must keep all its elements in order, but unless you specify how to order the elements, it's going to run into problems! What this means is that either
  • Any object you add to the TreeSet implements the Comparable interface. To implement this interface, your objects must contain a compareTo(Object o) method.
  • Or, when you initialise your TreeSet, pass a Comparator object. This Comparator has a compare(Object o1, Object o2) method that you should override.

  • Read more about the TreeSet on Sun's website.
    Shravan Durvasula

    Joined: Mar 06, 2004
    Posts: 19
    Thanks Fletcher. That helped.
    I agree. Here's the link:
    subject: TreeSet
    It's not a secret anymore!