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Hairy generics question

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I have a number of sets of matched parameterized classes: a bean, a
presenter, and a view.
The presenters and views have parallel inheritance hierarchies (where
T is the bean type, P the presenter type, and V is the view type):

public class CompA extends CompItem<AInfo, CompA, CompAView>
public class CompB extends CompItem<BInfo, CompB, CompBView>

public class CompAView extends CompItemView<AInfo, CompA, CompAView>
public class CompBView extends CompItemView<BInfo, CompB, CompBView>

public class CompItemView<T extends CompItemInfo,
                             P extends AbstractCompItem<T, P, V>,
                             V  extends CompItemViewInterface<T, P,
V>>
  extends AbstractCompItemView<T, P, V>
  implements CompItemViewInterface<T, P, V>

public abstract class CompItem<T extends CompItemInfo,
                                  P extends AbstractCompItem<T, P, V>,
                                  V extends CompItemViewInterface<T,
P, V>>
  extends AbstractCompItem<T, P, V>
  implements CompWidget<T>

Many of the views are the same, so I wanted to just use the base view
class instead of creating a separate view class for each presenter.
So I tried:

public class CompA extends CompItem<AInfo, CompA, CompItemView>

But I get an error that says "The type CompItemView is not a valid
substitute for the bounded parameter <V extends
CompItemViewInterface<T,P,V>> of the type CompItem<T,P,V>.
Why can I use a class that extends CompItemView for the V type, and
not CompItemView itself?

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Hairy generics question sclaflin <steve@steveclaflin.com> - 2012-02-21 06:30 -0800
  Re: Hairy generics question Lew <noone@lewscanon.com> - 2012-02-21 09:24 -0800
  Re: Hairy generics question Roedy Green <see_website@mindprod.com.invalid> - 2012-02-21 11:05 -0800
    Re: Hairy generics question Lew <noone@lewscanon.com> - 2012-02-21 12:09 -0800
  Re: Hairy generics question Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-02-21 18:04 -0800
    Re: Hairy generics question Lew <noone@lewscanon.com> - 2012-02-21 18:31 -0800
    Re: Hairy generics question Steven Simpson <ss@domain.invalid> - 2012-02-22 08:31 +0000
  Re: Hairy generics question sclaflin@webucator.com - 2012-02-24 11:12 -0800
    Re: Hairy generics question Lew <noone@lewscanon.com> - 2012-02-24 12:03 -0800
      Re: Hairy generics question sclaflin@webucator.com - 2012-02-24 14:07 -0800
        Re: Hairy generics question Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-02-24 15:36 -0800
          Re: Hairy generics question sclaflin@webucator.com - 2012-02-25 10:27 -0800
          Re: Hairy generics question Arved Sandstrom <asandstrom3minus1@eastlink.ca> - 2012-02-26 13:13 -0400
            What is Model View Presenter. (Was: Hairy generics question) Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-02-26 10:22 -0800
              Re: What is Model View Presenter. (Was: Hairy generics question) Lew <noone@lewscanon.com> - 2012-02-26 13:08 -0800
                Re: What is Model View Presenter. (Was: Hairy generics question) Arne Vajhøj <arne@vajhoej.dk> - 2012-02-26 18:17 -0500
                Re: What is Model View Presenter. (Was: Hairy generics question) sclaflin@webucator.com - 2012-02-28 06:22 -0800
            Re: Hairy generics question Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-02-28 09:46 -0800
              Re: Hairy generics question Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-02-28 09:49 -0800
              Re: Hairy generics question Lew <noone@lewscanon.com> - 2012-02-28 12:45 -0800
              Re: Hairy generics question Arved Sandstrom <asandstrom3minus1@eastlink.ca> - 2012-02-29 19:37 -0400
                Re: Hairy generics question Lew <noone@lewscanon.com> - 2012-02-29 22:32 -0800

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