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From: bob smith <bob@coolfone.comze.com>
Newsgroups: comp.lang.java.programmer
Subject: Re: default equals function?
Date: Fri, 10 Aug 2012 07:12:06 -0700 (PDT)
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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:
>=20
> > Let's say I have a class like this:
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> >
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> > public class Kern_Pair {
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> > 	int letter1, letter2;
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> >
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> > }
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> >
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> > Can someone tell me how the default equals function will behave?
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> >
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> > like
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> >
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> > kernpair1.equals(kernpair2)
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> >
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> > ?
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>=20
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>      Teachable Moment.
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>=20
>=20
>      The Kern_Pair class has no equals() method of its own, so it
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> inherits equals() from the nearest superclass that has one.  Walk
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> up the class inheritance tree to find the nearest ancestor with an
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> equals().  The class inheritance tree for Kern_Pair is fairly short:
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> Its immediate superclass is Object (because you didn't say "extends
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> SomethingElse"), so the equals() method for Kern_Pair *is* the
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> equals() method of Object.
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>=20
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>      Now all you need to do is go to the Javadoc and study what
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> Object's equals() will do.
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>=20
>=20
> --=20
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> Eric Sosman
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> esosman@ieee-dot-org.invalid

The equals method for class Object implements the most discriminating possi=
ble equivalence relation on objects; that is, for any non-null reference va=
lues x and y, this method returns true if and only if x and y refer to the =
same object (x =3D=3D y has the value true).