提高代码的重复性, 复用性
class 子类名 extends 父类名{
子类的属性
子类的方法
}
class Teacher{
String name;
int age;
public void sleep(){
System.out.println("Teacher is sleeping");
}
}
/**
*子类的定义
* class 子类 extends 父类
**/
class JavaTeacher extends Teacher{
public void teachJava(){
System.out.println("Teaching Java.");
}
}
class PHPTeacher extends Teacher{
public void teachPHP(){
System.out.println("Teaching PHP.");
}
}
class testDemo{
public static void main(String [] args) throws Exception{
JavaTeacher jt = new JavaTeacher();
jt.name = "Mr.Java";
jt.sleep();
PHPTeacher pt = new PHPTeacher();
pt.name = "Mr.PHP";
pt.sleep();
}
}
子类只能获得父类中的非private属性
对于private属性,可以通过get和set得到
对于private方法,无法继承
java中只能做单继承,不能继承多个
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