java - Extended Class And implemented interface having same method name -

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in java, if have classa extends classx , implements interfacey, , both classx , interfacey have methodc(), why don't have give implementation of methodc() in classa? kind of method overloading ?

because if classx has implementation of methodc() , classa extends classx, classa does have implementation of methodc() - classx's implementation of it.

if classa has it's own implementation of methodc(), called method overriding - classa's implementation override implementation of super class (classx).

overloading different issue entirely: overloading occurs when class has multiple methods same name/return type take different parameters. useful when want able perform same or similar operations different inputs, , has nothing overriding, useful when have subclass implementation of particular method needs different of super-class.

see here helpful discussion differences between them.


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