Java 学生管理系统

今天简单练习了一下 数组和循环的一些知识，写了一个小游戏，大致如下

/**
 * 一个小功能：学生管理系统
 * 1、添加学生信息
 * 2、显示学生信息
 * 3、删除学生信息
 * 4、修改学生信息
 * 5、查看学生信息
 * 6、排序
 * 7、退出
 */
public class StudentManage {

    public static void main(String[] args) {
        Integer[] studentId = new Integer[100];
        Integer[] studentScore = new Integer[100];
        String[] studentName = new String[100];

        int mumber = 0;
        Integer studentCount = 0;
        int time = 0;

        System.out.println("欢迎进入学生管理系统\n1、添加学生信息\n2、显示学生信息\n3、删除学生西悉尼\n4、修改学生信息\n5、查询学生信息\n6、排序\n7、退出");
        while (true) {
            System.out.println("请输入操作信息：");
            Scanner scanner = new Scanner(System.in);
            int number = scanner.nextInt();

            switch (number) {
                case 1:
                    studentCount = add(studentId, studentName, studentScore, studentCount);
                    System.out.println("添加成功");
                    break;
                case 2:
                    display(studentId, studentName, studentScore, studentCount);
                    break;
                case 3:
                    studentCount = delete(studentId, studentName, studentScore, studentCount);
                case 4:
                    update(studentId, studentName, studentScore, studentCount);
                    break;
                case 5:
                    select(studentId, studentName, studentScore, studentCount);
                    break;
                case 6:
                    sort(studentId, studentName, studentScore, studentCount);
                    break;
                case 7:
                    System.exit(0);
                    break;
                default:
                    System.out.println("请正确输入（1~7）的数字");
            }
        }
    }

    /**
     * 功能描述：添加学生信息
     *
     * @param studentId
     * @param studentName
     * @param studentScore
     * @param studentCount
     * @return
     */
    public static Integer add(Integer[] studentId, String[] studentName, Integer[] studentScore, Integer studentCount) {
        System.out.println("请输入学生ID");
        Scanner scan = new Scanner(System.in);
        studentId[studentCount] = scan.nextInt();
        System.out.println("请输入学习姓名");
        studentName[studentCount] = scan.next();
        System.out.println("请输入学生成绩");
        studentScore[studentCount] = scan.nextInt();
        studentCount++;
        return studentCount;
    }

    /**
     * 功能描述： 显示学生信息
     *
     * @param studentId
     * @param studentName
     * @param studentScore
     * @param studentCount
     */
    public static void display(Integer[] studentId, String[] studentName, Integer[] studentScore, Integer studentCount) {
        System.out.println("学号" + "\t姓名" + "\t成绩\n");
        for (int i = 0; i < studentCount; i++) {
            System.out.println(studentId[i] + "\t" + studentName[i] + "\t" + studentScore[i]);
            ;
        }
    }


    /**
     * 功能描述：删除学生信息
     *
     * @param studentId
     * @param studentName
     * @param studentScore
     * @param studentCount
     * @return
     */
    public static Integer delete(Integer[] studentId, String[] studentName, Integer[] studentScore, Integer studentCount) {
        Integer select = select(studentId, studentName, studentScore, studentCount);
        System.out.println("确定删除学生信息吗？(y/n)");
        Scanner scanner = new Scanner(System.in);
        char next = scanner.next().trim().toLowerCase().charAt(0);
        switch (next) {
            case 'n':
                System.out.println("您已经需求删除操作了...");
                break;
            case 'y':
                for (int i = 0; i < studentCount; i++) {
                    if (i < studentCount - 1) {
                        studentId[i] = studentId[i + 1];
                        studentName[i] = studentName[i + 1];
                        studentScore[i] = studentScore[i + 1];
                    }
                    studentId[i] = null;
                    studentName[i] = null;
                    studentScore[i] = null;
                    return studentCount--;
                }
        }
        return studentCount;
    }


    /**
     * 功能描述：查询学生信息
     *
     * @param studentId
     * @param studentName
     * @param studentScore
     * @param studentCount
     * @return
     */
    public static Integer select(Integer[] studentId, String[] studentName, Integer[] studentScore, Integer studentCount) {
        System.out.println("请输入学习姓名");
        Scanner scanner = new Scanner(System.in);
        String queryStudentName = scanner.next();
        for (int i = 0; i < studentCount; i++) {
            if (queryStudentName.trim().equals(studentName[i].trim())) {
                System.out.println("学号" + "\t姓名" + "\t成绩");
                System.out.println(studentId[i] + "\t" + studentName[i] + "\t" + studentScore[i]);
                return studentId[i];
            }
        }
        return null;
    }

    /**
     * 功能描述：修改学生信息
     *
     * @param studentId
     * @param studentName
     * @param studentScore
     * @param studentCount
     */
    public static void update(Integer[] studentId, String[] studentName, Integer[] studentScore, Integer studentCount) {

        Integer select = select(studentId, studentName, studentScore, studentCount);
        if (select == null) {
            System.out.println("你输入的信息有误，请重新输入");
        } else {
            System.out.println("请输入新学号");
            Scanner scanner = new Scanner(System.in);
            studentId[select] = scanner.nextInt();
            System.out.println("请输入新学生姓名");
            studentName[select] = scanner.next().trim();
            System.out.println("请输入新学生成绩");
            studentScore[select] = scanner.nextInt();
            System.out.println("修改完成");
        }
    }

    /**
     * 功能描述: 排序
     *
     * @param studentId
     * @param studentName
     * @param studentScore
     * @param studentCount
     */
    public static void sort(Integer[] studentId, String[] studentName, Integer[] studentScore, Integer studentCount) {
        System.out.println("请选择排序规则：1、按学号排序，2、按成绩排序");
        Scanner scanner = new Scanner(System.in);
        int num = scanner.nextInt();
        switch (num) {
            case 1:
                for (int i = 0; i < studentCount; i++) {
                    for (int j = 0; j < studentCount - i - 1; j++) {
                        if (studentId[j] > studentId[j + 1]) {
                            int temp = studentId[j];
                            studentId[j] = studentId[j + 1];
                            studentId[j = 1] = temp;

                            temp = studentScore[j];
                            studentScore[j] = studentScore[j + 1];
                            studentScore[j + 1] = temp;

                            String s = studentName[j];
                            studentName[j] = studentName[j + 1];
                            studentName[j + 1] = s;
                        }
                    }
                }
                display(studentId, studentName, studentScore, studentCount);
                break;
            case 2:
                for (int i = 0; i < studentCount; i++) {
                    for (int j = 0; j < studentCount - i - 1; j++) {
                        if (studentScore[j] > studentScore[j + 1]) {
                            int temp = studentId[j];
                            studentId[j] = studentId[j + 1];
                            studentId[j = 1] = temp;

                            temp = studentScore[j];
                            studentScore[j] = studentScore[j + 1];
                            studentScore[j + 1] = temp;

                            String s = studentName[j];
                            studentName[j] = studentName[j + 1];
                            studentName[j + 1] = s;
                        }
                    }
                }
                display(studentId, studentName, studentScore, studentCount);
                break;
            default:
                System.out.println("输入错误，退出程序");
        }
    }
}