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Re: default equals function?

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On Thursday, August 9, 2012 5:11:07 PM UTC-5, Eric Sosman wrote:
> On 8/9/2012 5:58 PM, bob smith wrote:
> 
> > Let's say I have a class like this:
> 
> >
> 
> > public class Kern_Pair {
> 
> > 	int letter1, letter2;
> 
> >
> 
> > }
> 
> >
> 
> > Can someone tell me how the default equals function will behave?
> 
> >
> 
> > like
> 
> >
> 
> > kernpair1.equals(kernpair2)
> 
> >
> 
> > ?
> 
> 
> 
>      Teachable Moment.
> 
> 
> 
>      The Kern_Pair class has no equals() method of its own, so it
> 
> inherits equals() from the nearest superclass that has one.  Walk
> 
> up the class inheritance tree to find the nearest ancestor with an
> 
> equals().  The class inheritance tree for Kern_Pair is fairly short:
> 
> Its immediate superclass is Object (because you didn't say "extends
> 
> SomethingElse"), so the equals() method for Kern_Pair *is* the
> 
> equals() method of Object.
> 
> 
> 
>      Now all you need to do is go to the Javadoc and study what
> 
> Object's equals() will do.
> 
> 
> 
> -- 
> 
> Eric Sosman
> 
> esosman@ieee-dot-org.invalid

The equals method for class Object implements the most discriminating possible equivalence relation on objects; that is, for any non-null reference values x and y, this method returns true if and only if x and y refer to the same object (x == y has the value true).

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default equals function? bob smith <bob@coolfone.comze.com> - 2012-08-09 14:58 -0700
  Re: default equals function? Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-08-09 18:11 -0400
    Re: default equals function? bob smith <bob@coolfone.comze.com> - 2012-08-10 07:12 -0700
      Re: default equals function? rossum <rossum48@coldmail.com> - 2012-08-10 16:47 +0100
      Re: default equals function? Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-08-10 12:29 -0400
  Re: default equals function? Jeff Higgins <jeff@invalid.invalid> - 2012-08-09 18:22 -0400
    Re: default equals function? Arne Vajhøj <arne@vajhoej.dk> - 2012-08-10 13:43 -0400

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