diff --git a/day09/src/com/inmind/extends02/Demo02.java b/day09/src/com/inmind/extends02/Demo02.java new file mode 100644 index 0000000..ce43e39 --- /dev/null +++ b/day09/src/com/inmind/extends02/Demo02.java @@ -0,0 +1,18 @@ +package com.inmind.extends02; +/* +.继承中成员变量(属性)的访问特点 +1.直接通过对象去访问,看对象创建语句=左边的内容,是谁就优先使用谁的成员变量,如果没有则向上(父类)找 +2.间接通过对象调用成员方法去访问,调用时,方法属于谁,就优先使用谁的成员变量,如果没有则向上(父类)找 + */ +public class Demo02 { + public static void main(String[] args) { + //创建一个子类对象 + Zi zi = new Zi(); + System.out.println(zi.num);//展示的是=左边类的成员变量,zi类中有直接获取 + System.out.println(zi.numFu);//展示的是=左边类的成员变量,zi类中没有,则向父类获取 + System.out.println(zi.numZi);//展示的是=左边类的成员变量,zi类中有直接获取 + //以下是间接访问 + zi.methodZi();//30 + zi.methodFu();//10 + } +} diff --git a/day09/src/com/inmind/extends02/Fu.java b/day09/src/com/inmind/extends02/Fu.java new file mode 100644 index 0000000..8d75717 --- /dev/null +++ b/day09/src/com/inmind/extends02/Fu.java @@ -0,0 +1,10 @@ +package com.inmind.extends02; + +public class Fu { + int num = 10; + int numFu = 20; + + public void methodFu(){ + System.out.println(num); + } +} diff --git a/day09/src/com/inmind/extends02/Zi.java b/day09/src/com/inmind/extends02/Zi.java new file mode 100644 index 0000000..465f37f --- /dev/null +++ b/day09/src/com/inmind/extends02/Zi.java @@ -0,0 +1,10 @@ +package com.inmind.extends02; + +public class Zi extends Fu{ + int num = 30; + int numZi = 40; + + public void methodZi(){ + System.out.println(num); + } +}