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Ranch Hand
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Hi Ranchers, could someone please help me in my understanding of Sets. I know how to scroll through a Set but would like to know if its possible to edit a value in a Set. Below is an example of what I would like to do. I would like change the value in the Set from "Hello" to "Goodbye". Is this possible? I fear it may not be as I'm trying to do it.
Thanks
Robbie.

 
Java Cowboy
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Objects that are in a HashSet should be immutable, because the HashSet relies on the fact that the hash codes of the objects stored in it remain constant. If you put mutable objects in a HashSet and change the value of such an object while it's in the set (so that its hash code changes), the HashSet will get confused. The same is true for the keys of HashMap.

What you can do is remove the old value and insert the new one:
 
robert stannard
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Thanks Jesper thats a good answer, I understand it now.

Regards
Robert.
 
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