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Overriding equals() & hashcode() in collections

ramya narayanan
Ranch Hand

Joined: Oct 06, 2008
Posts: 338
Dear all,
What is the need for overriding equals() & hashcode() in Collections .
Normally every instance by default inherits Object class which has equals() & hashcode() . Then why we should override it?
Regards.
Campbell Ritchie
Sheriff

Joined: Oct 13, 2005
Posts: 43368
    
  32
java NameDemo ramya ramya

See what comes out. You need to have two identical objects recoognised as identical to each other for the Collections to work.
 
Consider Paul's rocket mass heater.
 
subject: Overriding equals() & hashcode() in collections
 
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