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List<?> doubt

 
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List<?> l=new ArrayList<String> ;
l.add(null); why is this legal?i thought we cant add anything with ?
 
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Hi Raju,

we use generics to get compile time type safety. collection of <?> type does not let us add any element of specific type to maintain the type safety. Null does not have any type so adding this element would maintain the type safety feature of generics and would be completely valid.


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