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From: Abu Yahya <abu_yahya@invalid.com>
Newsgroups: comp.lang.java.programmer,comp.lang.java.help
Subject: Re: What's the difference between and instance and an object?
Date: Wed, 08 Jun 2011 22:07:28 +0530
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On 6/8/2011 10:03 PM, Patricia Shanahan wrote:

> There are two slightly different meanings of "X is an instance of Y".
>
> 1. X is an object whose class is Y. That is the meaning in which a
> constructor can only return an instance of its own class. The expression
> (new MyClass()), if it completes without exception or error, is always
> an object whose class is MyClass.
>
> 2. X is an object whose class implements or extends Y. This is the
> meaning that is tested by the "instanceof" operator. The expression
>
> (x instanceof Y)
>
> is true if x references an object whose class implements or extends Y.
>
> (x instanceof Object) is true unless x is null.


Thanks. That makes it /much/ clearer now.