public class Person {
}
public class Student extends Person{
}
public class Teacher extends Person {
}
public class Amplication {
public static void main(String[] args) {
Object object = new Student();
//instance 判断 = 号两边是否有父子关系
System.out.println(object instanceof Student); // true object是Student类的一个实例化
System.out.println(object instanceof Person); //true
System.out.println(object instanceof Object); // true
System.out.println(object instanceof Teacher); //false
System.out.println("================================");
//new一个Student类的实例,但是属于Person类
Person person = new Student();
System.out.println(person instanceof Student); //true
System.out.println(person instanceof Person); //true
System.out.println(person instanceof Object); //true
System.out.println(person instanceof Teacher); //false
System.out.println("=================================");
//new一个Student类的实例化,但属于Teacher类
Student student = new Student();
System.out.println(student instanceof Student); //true
System.out.println(student instanceof Person); //true
System.out.println(student instanceof Object); //true
// System.out.println(student instanceof Teacher); //false
}
}