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Enum class - equals() and hashCode() ?

kri shan
Ranch Hand

Joined: Apr 08, 2004
Posts: 1372
Whether enum classes need object's equals() and hashCode() ?
Campbell Ritchie
Sheriff

Joined: Oct 13, 2005
Posts: 38075
    
  22
Start in the Java™ Language Specification. Remember enum members are singletons, so == is adequate as a test for equality.
Rob Spoor
Sheriff

Joined: Oct 27, 2005
Posts: 19656
    
  18

Besides, all enum classes implicitly extend java.lang.Enum which has final implementations of both. equals uses == and hashCode uses Object.hashCode. Try overriding them in any enum and you'll get a compiler error.


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