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Generic methods doubt

Andry Dub
Ranch Hand

Joined: Nov 06, 2007
Posts: 43
Hi! Please explain me why I can't invoke addandDisp with parameters ls1 and object of type Object? What second parameter is allowed with first parameter will be ls1?

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Sandip Sarkar
Ranch Hand

Joined: Nov 25, 2007
Posts: 55

Have a look at the below forum discussion---

web page

i hope it will answer you.

Nitesh Kant

Joined: Feb 25, 2007
Posts: 1638

mmm, i am not sure what you wish to intend by List<? super Object>
This means either a superclass of Object(No class qualifies this rule) or the Object itself.
Since, there is no superclass of Object, its as good as saying List<Object>
If you do the above, everything should work fine.

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Kelvin Chenhao Lim
Ranch Hand

Joined: Oct 20, 2007
Posts: 513
Hi Andry,

I'm not sure what the issue here is. The code you provided compiles fine.

SCJP 5.0
prajal Mehta
Ranch Hand

Joined: Dec 03, 2007
Posts: 66
Hi kevin,

That code is from this site-
question no. 3

prajal Mehta
Ranch Hand

Joined: Dec 03, 2007
Posts: 66
I am not sure if the answer given is correct.
Please somebody explain the correct answer to me ..
Alexsandra Carvalho
Ranch Hand

Joined: Jul 13, 2007
Posts: 75
I really dont understand why this does not compile:

//call 2
List<? extends Object> ls2 = new LinkedList<Object>();
addandDisp(ls2,new Object());
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