java中的子类和父类问题(补充)

public class Person {

    private String name;

    private Integer age;

    public Person() {

       super();

       this.name = null;

       this.age = -1;

    }

    public Person(String name, Integer age) {

       super();

       this.name = name;

       this.age = age;

    }

}

public class Student extends Person{

    private String id;

    public Student() {

       super();

    }

    public Student(String id) {

       super();

       this.id = id;

    }

}

super()调用 super.Studeng();调用