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which version of method is actually called ? the reference one or actual object one ?

 
Ranch Hand
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In K&B book,there is an example



And then it says,

Animal c = new Horse();
c.buck(); // Can't invoke buck();
// Animal class doesn't have that method

Why will it not check for Horse class for buck method ?

Can somebody help me out in making clear picture when methods on reference variable are called and when methods on actual object is called ?
 
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in case of overriding method on object type is called and in case of overloading method on reference type is called
 
Ranch Hand
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Android VI Editor Java
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Animal c = new Horse();
c.buck(); // Can't invoke buck();
// Animal class doesn't have that method

Why will it not check for Horse class for buck method ?



I remember sometime ago seen similar post and the reply impressed me was

" Animal reference cannot used to call buck() method " because simply there is no button( buck) in the remote (Animal) to use
 
Greenhorn
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A Agr wrote:

Animal c = new Horse();
c.buck(); // Can't invoke buck();
// Animal class doesn't have that method

Why will it not check for Horse class for buck method ?

Can somebody help me out in making clear picture when methods on reference variable are called and when methods on actual object is called ?



Compiler will try to look for a buck() method in Animal and will not find it. So, this will not even compile
 
Ranch Hand
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The Reference variable's type not the object's type determines which method can be called and polymorphic method invocation apply only to overridden method. Thats why this code
runs eat() method of Horse.
As eat() method is an overridden method and Polymorphism applies to overriding so object's type( here Horse) method runs.
Here the reference type is Animal which doesn't have buck() method so it will not compile. buck() is not an overridden method but an instance method of Horse. Calling of method is determined at compile time based on reference type






 
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Animal reference cannot used to call buck() method " because simply there is no button( buck) in the remote (Animal) to use




This is a great explanation, it looks like a Sierra & Bates Head First quote!
 
Java Cowboy
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A Agr, welcome to JavaRanch.

Please use code tags when you post source code.
 
A Agr
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Alright. I didn't know before , will use code tags from now.
 
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