How can I add to List<? extends Number> data structures?

Posted by kunjaan on Stack Overflow See other posts from Stack Overflow or by kunjaan
Published on 2010-05-05T21:38:00Z Indexed on 2010/05/07 19:38 UTC
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java

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generics

I have a List which is declared like this :

 List<? extends Number> foo3 = new ArrayList<Integer>();

I tried to add 3 to foo3. However I get an error message like this:

The method add(capture#1-of ? extends Number) in the type List<capture#1-of ?
extends Number> is not applicable for the arguments (ExtendsNumber)

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