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instanceof operator

 
Greenhorn
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i want to ask a question that whether we can use instanceof operator with arrays?
 
Ranch Hand
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sure, if you want to check of array is instanceof int[], use this

 
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Originally posted by Ajay Singh:

if(array instanceof int[].class)



That should be

if (array instanceof int[]) ...
 
Ajay Singh
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thanks for correction!
 
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just wondering whether there is a way to compare instances of two objects

e.g.


cheers,

John
 
Ajay Singh
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you can't compare the way have done below. Howerver, you can use something like:

 
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It is exactly how you stated;
 
Ernest Friedman-Hill
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Originally posted by Christopher Elkins:
[QB]It is exactly how you stated;



No, it's not. The second argument to instanceof is the literal name of a class, not variable data of any kind, and certainly not an object.
 
lowercase baba
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This doesn't make sense to me:

that's like saying

what kind of object is fred? is satchmo? fred is an instance of Person, but satchmo is an instance of FredsCat.

unless your in a jazz music program, then satchmo could be a Person.

You can only have an instance of a class (or interface).

I think what you are trying to get at is, given two object references, you want to know if they are of the same type. Is that what you are asking?
[ January 08, 2007: Message edited by: Fred Rosenberger ]
 
Rippon Jalali
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actually the question was like this
# instanceof operator can be used with ...

1. interfaces
2. Arrays
3. Classes
4. All of the above

so should answer be the (4)
 
Ajay Singh
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Yes, the right hand should be any type, interface, array, class
 
Rippon Jalali
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i checked it for:
if(array instanceof int[]).
it is working .And ofcourse the answer should be (4).Thank you for your response
 
John Bartlett
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Yes that is what i meant, my method gets passed two Objects and i want to be able to tell whether they are the same type.
 
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