通过输入控制台命令查询学生成绩

咱就是说，这玩意好难，我捣鼓了一宿，有没有人帮我看看这个eclipse的

private static String[] stuNames = { "张三丰", "郭靖", "乔峰", "张无忌", "杨过" };
    private static String[] courses = { "JAVA", "C++", "Oracle", "Android" };
    private static int[][] sorces = { { 87, 76, 63, 98 }, { 67, 79, 83, 75 }, { 90, 76, 65, 60 }, { 84, 88, 63, 79 },
            { 72, 66, 58, 77 } };

    @SuppressWarnings("resource")
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String tip = "请输入以下指令：\n1、查询某门课程的平均分\n2、查询某位学生总分\n3、按照某门课程的成绩排序 输出\n"
                + "4、查询某位剩下的某门课程的成绩\n5、退出程序";
        System.out.println(tip);
        boolean flag = true;
        while (flag) {
            int n = sc.nextInt();
            switch (n) {
            case 1:
                System.out.println("请输入课程名称：");
                Scanner sc1 = new Scanner(System.in);
                String cName = sc1.nextLine();
                double avg = avg(cName);
                System.out.println(cName+"课程平均分数为：" + avg);
                break;
            case 2:
                System.out.println("请输入学生姓名：");
                Scanner sc2 = new Scanner(System.in);
                String uName = sc2.nextLine();
                double sum = sum(uName);
                System.out.println("学生"+uName+"总分数为：" + sum);
                break;
            case 3:
                System.out.println("请输入课程名称：");
                Scanner sc3 = new Scanner(System.in);
                String couName3 = sc3.nextLine();
                sort(couName3);
                break;
            case 4:
                System.out.println("请输入学生姓名：");
                Scanner sc4 = new Scanner(System.in);
                String stuName = sc4.nextLine();
                System.out.println("请输入课程名称：");
                String couName = sc4.nextLine();
                double score = get(stuName, couName);
                System.out.println("学生"+stuName+"的"+couName+"课程分数为："+score);
                break;
            case 5:
                System.exit(0);
                break;
            }
            System.out.println("是否继续操作？(y/n)");
            Scanner sc5 = new Scanner(System.in);
            String no = sc5.nextLine();
            if ("y".equals(no)) {
                flag = true;
                System.out.println(tip);
            } else {
                flag = false;
            }
        }
        
        
    }

    public static double avg(String cName) {
        double avg = 0;
        int num = -1;
        for (int i = 0; i < courses.length; i++) {
            if (cName.equals(courses[i])) {
                num = i;
            }
        }
        for (int j = 0; j < sorces.length; j++) {
            if (num >= 0) {
                avg += sorces[j][num];
            }
        }
        return avg / sorces.length;
    }

    // 查询学生总分
    public static double sum(String uName) {
        double sum = 0;
        int num = -1;
        for (int i = 0; i < stuNames.length; i++) {
            if (uName.equals(stuNames[i])) {
                num = i;
            }
        }
        for (int j = 0; j < courses.length; j++) {
            if (num >= 0) {
                sum += sorces[num][j];
            }
        }
        return sum;
    }

    public static void sort(String cName) {
        int num = -1;
        for (int i = 0; i < courses.length; i++) {
            if (cName.equals(courses[i])) {
                num = i;
            }
        }
        List<Integer> arr = new ArrayList<Integer>();
        for (int j = 0; j < sorces.length; j++) {
            if (num >= 0) {
                arr.add(sorces[j][num]);
            }
        }

        arr.sort((a1, a2) -> {
            if (a1 > a2) {
                return -1;
            } else {
                return 1;
            }
        });
        System.out.println(arr);
    }
    
    public static double get(String uName, String cName) {
        int x = -1;
        int y = -1;
        double score = 0;
        for (int i = 0; i < stuNames.length; i++) {
            if (uName.equals(stuNames[i])) {
                x = i;
            }
        }
        for (int i = 0; i < courses.length; i++) {
            if (cName.equals(courses[i])) {
                y = i;
            }
        }
        if (x >= 0 && y >= 0) {
            score = sorces[x][y];
        }
        return score;
    }