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Groups > comp.lang.java.programmer > #11708

Re: Converting Sets

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On 02/02/2012 08:34, Roedy Green wrote:
> What is the cleanest way to do this conversion?
>
> I have a Set<X>.
> I want a Set<Y>   where X implements Y.

This conversion exactly as asked:

Set<X> setOfX = obtainSetOfX();
Set<Y> setOfY = new YourPreferredSetImplementation<Y>(setOfX);

or:

Set<X> setOfX = obtainSetOfX();
Set<Y> setOfY = new YourPreferredSetImplementation<Y>();
setOfY.addAll(setOfX);

Conversion of a Set<X> to a Set<? extends Y>, ensuring the Set contains 
objects assignable to Y, but no new elements can be added to it:

Set<X> setOfX = obtainSetOfX();
Set<? extends Y> setOfY = setOfX;

Also, consider the possibility to build a Set<Y> and put X objects into 
it, in the first place.

--
Mayeul

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Thread

Converting Sets Roedy Green <see_website@mindprod.com.invalid> - 2012-02-01 23:34 -0800
  Re: Converting Sets Mayeul <mayeul.marguet@free.fr> - 2012-02-02 12:47 +0100
    Re: Converting Sets Roedy Green <see_website@mindprod.com.invalid> - 2012-02-02 05:32 -0800
      Re: Converting Sets Mayeul <mayeul.marguet@free.fr> - 2012-02-02 16:06 +0100
        Re: Converting Sets markspace <-@.> - 2012-02-02 09:21 -0800
          Re: Converting Sets Jim Janney <jjanney@shell.xmission.com> - 2012-02-02 13:13 -0700
            Re: Converting Sets markspace <-@.> - 2012-02-02 13:46 -0800
          Re: Converting Sets Roedy Green <see_website@mindprod.com.invalid> - 2012-02-02 16:29 -0800
            Re: Converting Sets Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-02-02 17:34 -0800
              Re: Converting Sets Arne Vajhøj <arne@vajhoej.dk> - 2012-02-04 20:49 -0500
                Re: Converting Sets Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-02-06 12:55 -0800
                Re: Converting Sets Arne Vajhøj <arne@vajhoej.dk> - 2012-02-06 20:47 -0500
                Re: Converting Sets Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-02-06 17:51 -0800
                Re: Converting Sets Arne Vajhøj <arne@vajhoej.dk> - 2012-02-06 20:57 -0500
            Re: Converting Sets markspace <-@.> - 2012-02-03 14:12 -0800
              Re: Converting Sets Lew <lewbloch@gmail.com> - 2012-02-03 22:32 -0800
            Re: Converting Sets Lew <lewbloch@gmail.com> - 2012-02-03 22:30 -0800
          Re: Converting Sets Lew <lewbloch@gmail.com> - 2012-02-03 22:33 -0800
      Re: Converting Sets Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-02-02 11:02 -0800
    Re: Converting Sets Roedy Green <see_website@mindprod.com.invalid> - 2012-02-02 18:25 -0800
      Re: Converting Sets markspace <-@.> - 2012-02-03 14:25 -0800

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