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Custom Immutable

 
Greenhorn
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Hi Team,



What is the reason that PersonImmutable class is not correct immutable class?
 
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Is this a homework question?

Are all members immutable?
 
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Why have you used Integer?
 
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Because it has mutable member variables (id and date)
 
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Integer (id) is not mutable.
 
Ranch Hand
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Special attention needed for  Date field

Below you can see an Immutable Class Sample :-

 
Campbell Ritchie
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Rob Spoor wrote:Integer (id) is not mutable.

So why didn't you simply use an int?
 
Rob Spoor
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The only reason I can think of is that null is allowed. The generated primary key of an entity in an ORM framework comes to mind. I'm not sure if this example qualifies though.
 
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