Is it better to pass reference to an object or pass individual attributes in an object in Java?

I'm dealing with legacy code and I constantly see method calls with multiple attributes from the same object being passed into a method:

update(user.getID(), user.getLanguage() etc...)
 

Is there a distinct advantage or disadvantage to doing it this way or would I just be as well to pass in the user object (in this case) and deal with attributes within the method called?

Cheers,

Alexei Blue.

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