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Re: Generics and downcasts

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On Tuesday, April 25, 2017 at 4:21:08 PM UTC-4, Arne Vajhøj wrote:
> <quote>
> Like many myths about Java performance, the erroneous belief that 
> declaring classes or methods as final results in better performance is 
> widely held but rarely examined. The argument goes that declaring a 
> method or class as final means that the compiler can inline method calls 
> more aggressively, because it knows that at run time this is definitely 
> the version of the method that's going to be called. But this is simply 
> not true. Just because class X is compiled against final class Y doesn't 
> mean that the same version of class Y will be loaded at run time. So the 
> compiler cannot inline such cross-class method calls safely, final or 
> not. Only if a method is private can the compiler inline it freely, and 
> in that case, the final keyword would be redundant.
> </quote>
> 
> Arne

Eclipse Cleanup adds final modifiers all over the place.  I don't recall if these are supposed to help performance.  All I know is 3 of the purposes for final.  1) declaring a public, usually static constant variable 2) declaring a class that should never be extended and 3) declaring a variable in a class that needs to pass directly into something, like a SwingWorker.

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Re: Generics and downcasts Marcel Mueller <news.5.maazl@spamgourmet.org> - 2017-04-25 22:07 +0200
  Re: Generics and downcasts Arne Vajhøj <arne@vajhoej.dk> - 2017-04-25 16:20 -0400
    Re: Generics and downcasts Eric Douglas <e.d.programmer@gmail.com> - 2017-04-25 13:35 -0700
      Re: Generics and downcasts Arne Vajhøj <arne@vajhoej.dk> - 2017-04-25 19:54 -0400
    Re: Generics and downcasts Marcel Mueller <news.5.maazl@spamgourmet.org> - 2017-04-25 22:40 +0200
      Re: Generics and downcasts Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-04-25 18:13 -0400
      Re: Generics and downcasts Arne Vajhøj <arne@vajhoej.dk> - 2017-04-25 19:53 -0400

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