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hash codes for classes that do not implement the hashCode() method

Rachel Glenn
Ranch Hand

Joined: Oct 24, 2012
Posts: 95
Suppose I have a class called Dog, as follows:




This class does not implement the hashCode() method.

Is it guaranteed then that all instances of Dog will produce unique hash codes (that I assume are generated by the java run time) ?
Matthew Brown
Bartender

Joined: Apr 06, 2010
Posts: 4240
    
    7

There's no guarantee they'll be unique. Thing about this: you can create more objects than there are int values, in which case you'd have to have duplicate hash codes. But there's a good chance that they will be distinct.
 
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