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# instanceof

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given:-

Question:- what is Foo[]...I mean the '[]' part ?? and what is Foo[1] ??
is it an array ?...afaik, arrays were something like:-
bla [] x = new bla[3];

TIA

(attempt at formatting)
[ November 13, 2004: Message edited by: Barry Gaunt ]

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Where did this notation come from? Talk about confusing...

My guess is that Foo[] is meant to be an array of Foo objects. That would then lead me to believe that Foo[1] would be a single Foo object from that array.

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I think I understand what you are trying to say

The first column is implying what to put in the first operand of the instanceof

For example:

(1st operand) instance of (Foo, Foo[], etc)

So for your first row, If you do Foo[] instanceof (Foo or Bar or Face) the result is false

Because Foo[] is not an instance of any of those objects

Netty poestel
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It's the table 3-2 from the 3rd chapter of the K & B book.

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Note in the table that Object is not a choice for the Foo[] truth table because that would return true.

I suppose the point of the table is to emphasize the types of objects (note small letters) in Java and that an array is not only a type of Object (note caps) but also a different type of object (note small letters) from the Objects (note caps) it holds.

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