java面向对象(类相关)

定义class

public class people {public void sayHello() {System.out.println( "hello!" );}}

实例化

people wang = new people();wang.sayHello();

继承

public class man extends people {}

调用继承的方法

man Mr_wang = new man();Mr_wang.sayHello();

重写继承的方法

public class man extends people {public void sayHello() {System.out.println( "man Hello!" );}}

构造方法和成员变量

public class man extends people {private String _name;public man( String name ){this._name = name;}public void sayHello() {System.out.println( this._name+"man Hello!" );}}

man Mr_wang = new man( "wangLiu_" );Mr_wang.sayHello();