Function

Function 扩展额外参数，3 至 6。

Function3<String, String, String, Integer> f = (a, b, c) -> 1;
Function4<String, String, String, String, Integer> f = (a, b, c, d) -> 1;
Function5<String, String, String, String, String, Integer> f = (a, b, c, d, e) -> 1;
Function6<String, String, String, String, String, String, Integer> ff = (a, b, c, d, e, f) -> 1;