Java做一天了已经很焦虑了，还是没搞出来

学校接口：

public interface School {

    /**
     * 学校名称
     *
     * @return
     */
    default String getSchoolName() {
        return null;
    }

    /**
     * 学校编号
     *
     * @return
     */
    default String getSchoolNo() {
        return null;
    }

    /**
     * 学校所在城市
     *
     * @return
     */
    default String getSchoolCity() {
        return null;
    }

    void showInfo();
}

学生类：

public abstract class Student implements School {

    /**
     * 学号
     */
    private String no;

    /**
     * 姓名
     */
    private String name;

    /**
     * 年龄
     */
    private Integer age;

    /**
     * 英语成绩
     */
    private Double englishScore;

    public Student(String no, String name, Integer age, Double englishScore) {
        this.no = no;
        this.name = name;
        this.age = age;
        this.englishScore = englishScore;
    }

    /**
     * 输出属性
     */
    @Override
    public abstract void showInfo();


    public String getNo() {
        return no;
    }

    public void setNo(String no) {
        this.no = no;
    }

    public String getName() {
        return name;
    }

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

    public Integer getAge() {
        return age;
    }

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

    public Double getEnglishScore() {
        return englishScore;
    }

    public void setEnglishScore(Double englishScore) {
        this.englishScore = englishScore;
    }

    @Override
    public String toString() {
        return "Student{" +
                "no='" + no + '\'' +
                ", name='" + name + '\'' +
                ", age=" + age +
                ", englishScore=" + englishScore +
                '}';
    }
}

Senior 类：

public class Senior extends Student {

    /**
     * 总分数
     */
    private Double totalScore;

    /**
     * 挂科门数
     */
    private Double failCount;

    /**
     * 是否满足毕业要求
     */
    private Boolean graduate;

    public Senior(String no, String name, Integer age, Double englishScore) {
        super(no, name, age, englishScore);
    }

    @Override
    public void showInfo() {
        System.out.println(this);
    }

    @Override
    public String toString() {
        return "Senior{" +
                "totalScore=" + totalScore +
                ", failCount=" + failCount +
                ", graduate=" + graduate +
                '}';
    }

    public Double getTotalScore() {
        return totalScore;
    }

    public void setTotalScore(Double totalScore) {
        this.totalScore = totalScore;
    }

    public Double getFailCount() {
        return failCount;
    }

    public void setFailCount(Double failCount) {
        this.failCount = failCount;
    }

    public Boolean getGraduate() {
        return graduate;
    }

    public void setGraduate(Boolean graduate) {
        this.graduate = graduate;
    }
}

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