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Map map = new Hashmap()

yamini nadella
Ranch Hand

Joined: Apr 13, 2004
Posts: 257
Assume Map interface has 10 public methods. Hashmap class implemented Map interface and some extra methods, total 20 public methods.
Map map = new Hashmap()
From this map object how many methods can I access. Can I access 10 or 20?
Barry Gaunt
Ranch Hand

Joined: Aug 03, 2002
Posts: 7729
You can only access the 10 methods of Map through the reference map.
You would, in your example, have to cast the reference map to a HashMap reference if you wanted to access all of HashMap's methods.
For instance: ((HashMap)map).someMethodSpecificToHashMap()

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