初识对象和类

对象的生命周期

创建类

包的创建和使用类成员的访问控制 类成员与实例成员

继承嵌入类 Inner Classes

接口

-Acquaintance-type object and object type to create the life cycle of packet creation and use of the members of the Access Control category of members and members of the succession of examples of types of embedded interface Inner Classes