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Duplicates in HashSet

 
Greenhorn
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Hi, can somebody tell me why seemingly equal Person object are added to HashSet. It prints Total 5 for size, I thought it should be 3. What I'm doing wrong when trying to override equals? Code is from K&B master exam, I added something to it...
 
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It's the hashCode() method -- with a capital C.

Henry
 
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Hi,

change hashcode to hashCode() with upper 'C', and it should work fine
 
Alexander Danilou
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Thanks. Amazing how simple things can elude you sometimes...
 
Java Cowboy
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This is exactly what the @Override annotation is for. If you would have used it in your code, like this:

Then you would have gotten a compiler error, because hashcode() is not overriding a method in a superclass.

(Note, annotations are not part of the SCJP exam, but it's important to understand them, because they are being used more and more, especially in Java EE).
 
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