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Polymorphic method declarations  RSS feed

 
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A reference variable can refer to any object of the same type as the declared reference, or it can refer to any subtype of the declared type!



I have seen this in K & B SCJP Book. What is the main advantage in this kind of method declarations ?


What is the problem with this declaration ?


When should we choose polymorphic method declarations?
 
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In those cases where you want type specific methods to be executed. Like Animal class having an eat method. Now based on cat and dog subclasses object, you prefer to have the eat method of either dog/cat executed.

Example:


[ February 08, 2008: Message edited by: Gitesh Ramchandani ]
 
It is sorta covered in the JavaRanch Style Guide.
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