Java多态数组

package com.leo.polyArr;
// 父类
public class Person {
    private String name;
    private int age;

    public Person(String name, int age) {
        this.name = name;
        this.age = age;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public String say() {
        return "name = " + name + " age = "+ age;
    }
}

package com.leo.polyArr;

public class Student extends Person{
    private double score;
    public Student(String name, int age, double score) {
        super(name, age);
        this.score = score;
    }

    public double getScore() {
        return score;
    }

    public void setScore(double score) {
        this.score = score;
    }

    @Override
    public String say() {
        return "Student " + super.say() + "score = " + score;
    }

    public void study() {
        System.out.println("学生在学习");
    }
}

package com.leo.polyArr;

public class Teacher extends Person{
    private double salary;

    public Teacher(String name, int age, double salary) {
        super(name, age);
        this.salary = salary;
    }

    public double getSalary() {
        return salary;
    }

    public void setSalary(double salary) {
        this.salary = salary;
    }

    @Override
    public String say() {
        return "Teacher " + super.say() + "salary = " + salary;
    }

    public void teach() {
        System.out.println("老师在上课");
    }
}

package com.leo.polyArr;

public class Poly {
    public static void main(String[] args) {
        Person[] persons = new Person[5];
        persons[0] = new Person("Leo", 30);
        persons[1] = new Student("Mike", 20, 100);
        persons[2] = new Student("John", 22,90);
        persons[3] = new Teacher("Scott", 35,10000);
        persons[4] = new Teacher("King",   40,20000);

        for (int i = 0; i < persons.length; i++) {
            System.out.println(persons[i].say());
            if (persons[i] instanceof Student) {
                Student student = (Student)persons[i];
                student.study();
            } else if(persons[i] instanceof Teacher) {
                Teacher teacher = (Teacher)persons[i];
                teacher.teach();
            } else {
                System.out.println("你的类型错误，请检查");
            }
        }
    }
}