java - Should all the methods in an abstract superclass be declared abstract? -


i haven't been able find clear answer this. there definitive answer?

short answer - no. if you're writing methods listed abstract, consider interface instead.

long answer: in abstract class have ability have methods implemented (generally, methods intend share among extenders of abstract class) , other methods can abstract force extenders implement them. methods (abstract , implemented) can freely referenced other methods usual.


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