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wildcards doubt again

 
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In generics using wildcards,
cannt we have ? on the RHS of Collection -declaration & initialization experession.
ie.
List<?> mylist=new ArrayList<? extends Object>();
Why is this so?
--From K&B ,chap7 pg 596

Thank you
 
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In the first part you declare a reference type and with the wild card you say the reference could be <? extends ...> Every object that extends from the given object type.

In the second part you create an object. This object should be of a certain class and could not defined as we don't know what kind of object it is but it could extend a given objecttype. No it is just a object of type X.

So you cannot use wild card notation in the object creation only as a reference.
 
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