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Re: default equals function?

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From "Eric Sosman" <eric.sosman@1:261/38.remove-t9h-this>
Subject Re: default equals function?
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  To: bob smith
From: Eric Sosman <esosman@ieee-dot-org.invalid>

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

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Thread

default equals function? "bob smith" <bob.smith@1:261/38.remove-t9h-this> - 2012-08-10 18:39 +0000
  Re: default equals function? "Eric Sosman" <eric.sosman@1:261/38.remove-t9h-this> - 2012-08-10 18:39 +0000
    Re: default equals function? "bob smith" <bob.smith@1:261/38.remove-t9h-this> - 2012-08-10 18:39 +0000
      Re: default equals function? "rossum" <rossum@1:261/38.remove-t9h-this> - 2012-08-10 18:39 +0000
      Re: default equals function? "Eric Sosman" <eric.sosman@1:261/38.remove-t9h-this> - 2012-08-10 18:39 +0000
  Re: default equals function? "Jeff Higgins" <jeff.higgins@1:261/38.remove-t9h-this> - 2012-08-10 18:39 +0000
    Re: default equals function? "Arne Vajhøj" <arne.vajhøj@1:261/38.remove-6gh-this> - 2012-08-10 19:41 +0000

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