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What this mean again?

 
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What is the following mean??

We can always cast between an interface and a non-final object.
 
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Assuming you are talking about compile time, what this means is:
You can cast a class referrence to "any" interface reference,
as long as the class is not a final class. The class does
not need to implement the interface.
However, if the class is a final class, it can only be casted
to the interface that it implements.
Run-time check is another story.
 
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Yes I agree because even if the class does'nt implement the interface one of its subclasses might do. This is not the case if the class is final.
 
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