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Santosh Kumar Nayak
Ranch Hand

Joined: Aug 02, 2011
Posts: 141
What is the meaning of the Collection<? extends String> my_plan

Can some one explain me the above syntax.
Jesper de Jong
Java Cowboy
Saloon Keeper

Joined: Aug 16, 2005
Posts: 15091

That's generics with wildcards. See this tutorial: Generics - Wildcards.

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Tony Docherty

Joined: Aug 07, 2007
Posts: 2839
That use of an upper bounded wildcard is actually pointless as the String class is final and so there are no subclasses of String.
Consider Paul's rocket mass heater.
subject: collections
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