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Polymorphism issue in the test code

 
Niccola LeBaron
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I don't know why it doesn't like the getName() call. this is my first post here so if I am missing something that I should have included please just let me know.



There is a super class called shapes and then two under that. TwoDimensionalShape and ThreeDimensionalShape
Under TwoDimensionalShape there are several subclasses. Circle, Square and triangle. Seems like everything is fine except the getName() call.
Here is what I have for one of the subclasses.

 
Hauke Ingmar Schmidt
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Welcome to the Ranch!

Please UseCodeTags.

The compiler uses the variable for determining if he can call the method. The variable you are calling getName on (currentShape) is of type Shape. So if Shape has no getName method it will not work, no matter whether the subclasses have such a method.

But of course the runtime will call the method of the current object and it's type.
 
Niccola LeBaron
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Thanks I figured out the code tags.

I added the getName method to shape and that fixed it. Thanks so much
 
Hauke Ingmar Schmidt
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Now your code is readable. In line 17 and 22 you create variables with the specific subtype. What about calling the methods on these variables? Not in every case you can change the interface of the super class.
 
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