questions for dynamic binding and signature method in java ab -

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matching method signature , binding method implementation 2 sepearate issue ,what's wrong follows code?

container c5 = new jbutton();  object c6 = new jbutton();  c5.add(c6);       //----it wrong,why?

for me , c5 reference variable contain reference object of jbutton,and jbutton extends class component,so should right why ?

java single-dispatch language. means method signature analysis done @ compile time, not run time.

the type of c6 object. (yes, assign jbutton, declared type of variable still object.) when java looks @ c5 (a container) , methods, doesn't see add() method takes object. flags error.


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