public class Main { public static void main(String[] args) { Person p = new Person("小明", 12); Student s = new Student("小红", 20, 99); // TODO: 定义PrimaryStudent,从Student继承,新增grade字段: Student ps = new PrimaryStudent("小军", 9, 100, 5); System.out.println(ps.getScore()); }}class Person { protected String name; protected 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; }}class Student extends Person { protected int score; public Student(String name, int age, int score) { super(name, age); this.score = score; } public int getScore() { return score; }}class PrimaryStudent extends Student { // TODO private final int grade; public PrimaryStudent(String name, int age, int score, int grade) { super(name, age, score);//调用父类构造方法 this.grade = grade; }}
I WILL.