The Java is clean because it's perfectly understandable. I don't have to think about "+ 1m" meaning month, minute, or milli-. Verbose, yes, but the meaning is 100% unambiguous which I think makes it a better API.
> overloading strings
I'm pretty sure writing "+ 1m" is more of an overloading of a string than ".plusMinutes(1)".
> overloading strings
I'm pretty sure writing "+ 1m" is more of an overloading of a string than ".plusMinutes(1)".