From b5a8af3ffbe16da7fa3b752a6256987db83415e6 Mon Sep 17 00:00:00 2001 From: xuxin <840198532@qq.com> Date: Sat, 23 May 2026 10:23:12 +0800 Subject: [PATCH] =?UTF-8?q?day09-=E7=BB=A7=E6=89=BF=E4=B8=AD=E6=9E=84?= =?UTF-8?q?=E9=80=A0=E6=96=B9=E6=B3=95=E7=9A=84=E8=AE=BF=E9=97=AE=E7=89=B9?= =?UTF-8?q?=E7=82=B9?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- .../inmind/extends_constructor04/Demo05.java | 17 +++++++++++++++++ .../com/inmind/extends_constructor04/Fu.java | 16 ++++++++++++++++ .../com/inmind/extends_constructor04/Zi.java | 9 +++++++++ 3 files changed, 42 insertions(+) create mode 100644 day09/src/com/inmind/extends_constructor04/Demo05.java create mode 100644 day09/src/com/inmind/extends_constructor04/Fu.java create mode 100644 day09/src/com/inmind/extends_constructor04/Zi.java diff --git a/day09/src/com/inmind/extends_constructor04/Demo05.java b/day09/src/com/inmind/extends_constructor04/Demo05.java new file mode 100644 index 0000000..c2be63e --- /dev/null +++ b/day09/src/com/inmind/extends_constructor04/Demo05.java @@ -0,0 +1,17 @@ +package com.inmind.extends_constructor04; +/* +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) { + //创建子类对象 + Zi zi = new Zi(); + //创建父类对象 + Fu fu = new Fu(10); + + System.out.println("程序结束"); + } +} diff --git a/day09/src/com/inmind/extends_constructor04/Fu.java b/day09/src/com/inmind/extends_constructor04/Fu.java new file mode 100644 index 0000000..f69f3b8 --- /dev/null +++ b/day09/src/com/inmind/extends_constructor04/Fu.java @@ -0,0 +1,16 @@ +package com.inmind.extends_constructor04; + +public class Fu { + int num; + + //父类的无参构造方法 + public Fu(){ + System.out.println("父类无参构造方法"); + } + + //父类的有参构造方法 + 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_constructor04/Zi.java b/day09/src/com/inmind/extends_constructor04/Zi.java new file mode 100644 index 0000000..15c63b9 --- /dev/null +++ b/day09/src/com/inmind/extends_constructor04/Zi.java @@ -0,0 +1,9 @@ +package com.inmind.extends_constructor04; + +public class Zi extends Fu{//子类继承了父类,拥有了父类的非私有的成员 + + public Zi(){ + //super(10);//注意:如果不写该行代码,编译器会自动添加super(),调用父类的无参构造,并且必须在第一行 + System.out.println("子类的无参构造方法"); + } +}