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Need to know some things on generics

Dinesh Tahiliani
Ranch Hand

Joined: Aug 06, 2007
Posts: 486
Diffrence between
1. List<?>
2. List<?super Number>
3. List<? extends Number>
4. List<Number>

Please explain with example Please....


Thanks<br />Dinesh
Jesper de Jong
Java Cowboy
Saloon Keeper

Joined: Aug 16, 2005
Posts: 14114
    
  16

See Sun's Java tutorial on generics, especially the section about wildcards.


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