Java面向对象高级性题

在主函数中定义父类引用子类是怎么个意思，怎么做，渴望代码，什么意思，不是很明白，望解答

public class EmployeeTest {

    public static void main(String[] args) {
        Employee saler = new Saler();
        //销售员月薪
        saler.setSalary(20);
        saler.showSalary();
        
        //经理月薪
        Employee manger = new Manger();
        manger.setSalary(10000);
        manger.showSalary();
    }
    
}

public abstract class Employee {

public double salary;

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

public abstract void showSalary();

}

public class Saler extends Employee {

    @Override
    public void showSalary() {
        System.out.println("销售员的月薪为：" + salary * 8 * 30);
    }

}

public class Manger extends Employee {

    @Override
    public void showSalary() {
        System.out.println("经理的月薪为：" + salary);
    }

}

以上如有帮助请采纳

是多态
而且你的子类可以不用定义抽象类了，定义了的话不能实例化