Whose responsibility is it to check data validity?

Question

I am confused as to whether it is the *caller* or the *callee's* responsibility to check for data legality.Should the *callee* check whether passed-in arguments meet some other requirements so that the *callee* method can execute normally? Or it is the *caller's* responsibility to do this?

Answer 1

I've seen it done both places.

It is a design topic that gets discussed.