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Generic type wild-card ? vs Object

 
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I don't understand the need for the wild-card character, "?" in generics.

Can someone explain to me why we need List<?> and why List<Object> isn't good enough. I don't understand the difference.

Kaydell
 
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List<Object> imposes more restriction than List<?>.
You can only pass List<Object> where List<Object> is required not
List<A>, List<B> and so.

With using wildcard ? parameterized type you can pass List parameterized with
any type.


Thanks,
 
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