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Re: Alternative to TreeSet?

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On 05/06/2013 06:10 PM, laredotornado@zipmail.com wrote:
> Hi,
>
> We're using Java 6.  Is there a java.util.Set data structure that can
> return a sorted list of elements and can contain two elements even if
> compareTo returns 0 against those two elements but calling equals
> against the two elements returns false?  TreeSet doesn't do the job.

Implement a Comparator and pass it to the TreeSet. The Comparator can 
sort objects for which equals returns false in any arbitrary (but 
deterministic) order.

> In our example, we have products with an order ID column, so two
> products could have the same order ID but may not be equal.  We would
> like to sort the products based on this order ID, however.

The Comparator would sort the products based on their ID first - and if 
the IDs are equal it would sort them based on other attributes.

Is that what you want?



Regards,
   Sven

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Thread

Alternative to TreeSet? laredotornado@zipmail.com - 2013-05-06 08:10 -0700
  Re: Alternative to TreeSet? Eric Sosman <esosman@comcast-dot-net.invalid> - 2013-05-06 11:19 -0400
    Re: Alternative to TreeSet? Lew <lewbloch@gmail.com> - 2013-05-06 11:33 -0700
    Re: Alternative to TreeSet? Arved Sandstrom <asandstrom2@eastlink.ca> - 2013-05-06 18:01 -0300
  Re: Alternative to TreeSet? Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2013-05-06 08:25 -0700
    Re: Alternative to TreeSet? Robert Klemme <shortcutter@googlemail.com> - 2013-05-07 07:58 +0200
  Re: Alternative to TreeSet? Roedy Green <see_website@mindprod.com.invalid> - 2013-05-07 09:21 -0700
  Re: Alternative to TreeSet? Sven Köhler <remove-sven.koehler@gmail.com> - 2013-05-07 19:36 +0300

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