diff --git a/day09/src/com/inmind/extends_constructor05/Demo05.java b/day09/src/com/inmind/extends_constructor05/Demo05.java
new file mode 100644
index 0000000..2ed023c
--- /dev/null
+++ b/day09/src/com/inmind/extends_constructor05/Demo05.java
@@ -0,0 +1,14 @@
+package com.inmind.extends_constructor05;
+/*
+继承中构造方法的访问特点
+1.创建子类对象时，一定会调用父类的构造方法
+2.super调用父类的构造方法时，必须在子类的构造方法的第一行
+3.super可以调用父类的有参构造方法。
+ */
+public class Demo05 {
+    public static void main(String[] args) {
+        Fu fu = new Fu();
+        System.out.println("--------------");
+        Zi zi = new Zi();
+    }
+}
diff --git a/day09/src/com/inmind/extends_constructor05/Fu.java b/day09/src/com/inmind/extends_constructor05/Fu.java
new file mode 100644
index 0000000..ada2009
--- /dev/null
+++ b/day09/src/com/inmind/extends_constructor05/Fu.java
@@ -0,0 +1,15 @@
+package com.inmind.extends_constructor05;
+
+public class Fu {
+    int num;
+
+    public Fu(){
+        System.out.println("父类无参构造方法");
+    }
+
+    public Fu(int num){
+        System.out.println("父类有参构造方法");
+        this.num = num;
+    }
+
+}
diff --git a/day09/src/com/inmind/extends_constructor05/Zi.java b/day09/src/com/inmind/extends_constructor05/Zi.java
new file mode 100644
index 0000000..17676f0
--- /dev/null
+++ b/day09/src/com/inmind/extends_constructor05/Zi.java
@@ -0,0 +1,10 @@
+package com.inmind.extends_constructor05;
+
+public class Zi extends Fu{
+    public Zi(){
+        super(1);//如果不写这行代码，编译器也会默认添加，super()调用父类的无参构造方法
+        System.out.println("子类无参构造方法");
+    }
+
+
+}
diff --git a/day09/src/com/inmind/override04/Demo04.java b/day09/src/com/inmind/override04/Demo04.java
new file mode 100644
index 0000000..f8585bf
--- /dev/null
+++ b/day09/src/com/inmind/override04/Demo04.java
@@ -0,0 +1,16 @@
+package com.inmind.override04;
+
+public class Demo04 {
+    public static void main(String[] args) {
+        //来一个旧手机
+        Phone phone = new Phone();
+        phone.call();
+        phone.sendMessage();
+        phone.show();
+        //来一个新手机
+        NewPhone newPhone = new NewPhone();
+        newPhone.call();
+        newPhone.sendMessage();
+        newPhone.show();
+    }
+}
diff --git a/day09/src/com/inmind/override04/NewPhone.java b/day09/src/com/inmind/override04/NewPhone.java
new file mode 100644
index 0000000..0134192
--- /dev/null
+++ b/day09/src/com/inmind/override04/NewPhone.java
@@ -0,0 +1,17 @@
+package com.inmind.override04;
+
+public class NewPhone extends Phone{
+    //老的功能直接继承
+
+    //对于部分功能要进行扩展增强，就重写
+    //快捷键：ctrl+o
+    //重写的作用：对父类的方法进行选择性的扩展
+    @Override
+    public void show() {
+        //super.show();//调用父类的原本功能（沿袭父类的功能）
+        //以下代码就是子类对父类的功能不满足，则进行扩展增强
+        System.out.println("头像显示");
+        System.out.println("电诈提示");
+        System.out.println("展示归属地");
+    }
+}
diff --git a/day09/src/com/inmind/override04/Phone.java b/day09/src/com/inmind/override04/Phone.java
new file mode 100644
index 0000000..a6a3cdf
--- /dev/null
+++ b/day09/src/com/inmind/override04/Phone.java
@@ -0,0 +1,16 @@
+package com.inmind.override04;
+
+public class Phone {
+
+    public void call(){
+        System.out.println("打电话");
+    }
+
+    public void sendMessage(){
+        System.out.println("发短信");
+    }
+
+    public void show(){
+        System.out.println("旧手机来电号码显示");
+    }
+}