Member method
1.Definition of method: including method declaration and method implementation
2 . Method declaration:
(1) What the object can do.
(2) Composition: Modifier, return value type, method name, formal parameter list and thrown exception.
(3) There can be 0~n modifiers in a method, and there is no sequence of positions among multiple modifiers.
3 .Method implementation
(1) How the object is represented.
(2){// the realization of the method.}