Creating new data types: class

3.1 建立新的数据类型: class

Historically, however, most object-oriented languages have used the keyword class to mean "I 'm about to tell you what a new type of object looks like."

class ATypeName { /* class body goes here */ }

这样就建立了一种新的类型，接下来就可以用new创建这种类型的一个新对象：

ATypeName a = new ATypeName();