package oop.Test05;
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public class Application {
public static void main(String[] args) {
//new Student();
//一个对象的实际类型是确定的
//new Person()
//可以指向的实际类型是不确定的
//父类的引用指向子类
//student能调用的方法都是自己的或者继承父类的
Student s1= new Student();
//person父亲型,可以指向子类,但是不能调用子类独有的方法.
Person s2=new Student();
Object s3=new Student();
//对象能执行那些方法主要看左边的类型,和右边的关系不大
s2.run();//子类重写了父类的方法,执行子类的方法
s1.run();
s1.eat();
s1.eat();
((Student)s2).eat();
//object>string
//object>Person>teacher
//object>Person>student
Object object=new Student();
Person person=new Student();
System.out.println(object instanceof Student);
System.out.println(object instanceof Person);
System.out.println(object instanceof Object);
System.out.println(object instanceof Teacher);
System.out.println(object instanceof String);
System.out.println("+++++++++++++++++++++++++++++++++++++++");
System.out.println(person instanceof Student);
System.out.println(person instanceof Person);
System.out.println(person instanceof Object);
System.out.println(person instanceof Teacher);
/*System.out.println(person instanceof String);*/
Student student=new Student();
System.out.println("============================================");
System.out.println(student instanceof Student);
System.out.println(student instanceof Person);
System.out.println(student instanceof Object);
/* System.out.println(student instanceof Teacher);*/
/*System.out.println(student instanceof String);*/
/* System.out.println(X instanceof Y);*///能不能编译通过主要看是否有父子关系
}
}
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