根据一下内容实现用Java写一个学生成绩管理系统 要求1：带有图形界面。要求2：登录时输入用户名密码。要求3：能够录入、查询、修改、删除课程。 要求4：能够录入、查询、修改、删除学生某个课程的成绩。 要求5：能够持久化。代码不要太长！

好的，以下是一个简单的学生成绩管理系统的Java实现：

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.util.*;

public class ScoreManagementSystem extends JFrame implements ActionListener {
    private JLabel userLabel, passLabel, courseLabel, studentLabel, gradeLabel;
    private JTextField userField, passField, courseField, studentField, gradeField;
    private JButton loginButton, addButton, queryButton, modifyButton, deleteButton;
    private JTextArea resultArea;

    // 存储用户名和密码
    private Map<String, String> userMap = new HashMap<>();

    // 存储课程信息
    private List<Course> courseList = new ArrayList<>();

    // 存储学生成绩
    private Map<String, Map<String, Integer>> scoreMap = new HashMap<>();

    public ScoreManagementSystem() {
        initUI();
        initData();
    }

    // 初始化界面
    private void initUI() {
        userLabel = new JLabel("用户名：");
        passLabel = new JLabel("密码：");
        courseLabel = new JLabel("课程名：");
        studentLabel = new JLabel("学生名：");
        gradeLabel = new JLabel("成绩：");

        userField = new JTextField(10);
        passField = new JPasswordField(10);
        courseField = new JTextField(10);
        studentField = new JTextField(10);
        gradeField = new JTextField(10);

        loginButton = new JButton("登录");
        addButton = new JButton("添加");
        queryButton = new JButton("查询");
        modifyButton = new JButton("修改");
        deleteButton = new JButton("删除");

        resultArea = new JTextArea(10, 30);
        resultArea.setEditable(false);

        JPanel loginPanel = new JPanel(new GridLayout(2, 2));
        loginPanel.add(userLabel);
        loginPanel.add(userField);
        loginPanel.add(passLabel);
        loginPanel.add(passField);

        JPanel coursePanel = new JPanel(new GridLayout(4, 2));
        coursePanel.add(courseLabel);
        coursePanel.add(courseField);
        coursePanel.add(studentLabel);
        coursePanel.add(studentField);
        coursePanel.add(gradeLabel);
        coursePanel.add(gradeField);

        JPanel buttonPanel = new JPanel(new GridLayout(1, 5));
        buttonPanel.add(addButton);
        buttonPanel.add(queryButton);
        buttonPanel.add(modifyButton);
        buttonPanel.add(deleteButton);

        Container contentPane = getContentPane();
        contentPane.setLayout(new BorderLayout());
        contentPane.add(loginPanel, BorderLayout.NORTH);
        contentPane.add(coursePanel, BorderLayout.CENTER);
        contentPane.add(buttonPanel, BorderLayout.SOUTH);
        contentPane.add(new JScrollPane(resultArea), BorderLayout.EAST);

        loginButton.addActionListener(this);
        addButton.addActionListener(this);
        queryButton.addActionListener(this);
        modifyButton.addActionListener(this);
        deleteButton.addActionListener(this);

        setTitle("学生成绩管理系统");
        setSize(500, 300);
        setLocationRelativeTo(null);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }

    // 初始化数据
    private void initData() {
        try {
            // 从文件中读取用户名和密码
            Scanner scanner = new Scanner(new File("users.txt"));
            while (scanner.hasNextLine()) {
                String line = scanner.nextLine();
                String[] tokens = line.split(",");
                userMap.put(tokens[0], tokens[1]);
            }
            scanner.close();

            // 从文件中读取课程信息
            scanner = new Scanner(new File("courses.txt"));
            while (scanner.hasNextLine()) {
                String line = scanner.nextLine();
                String[] tokens = line.split(",");
                courseList.add(new Course(tokens[0], tokens[1]));
            }
            scanner.close();

            // 从文件中读取学生成绩
            scanner = new Scanner(new File("scores.txt"));
            while (scanner.hasNextLine()) {
                String line = scanner.nextLine();
                String[] tokens = line.split(",");
                String student = tokens[0];
                String course = tokens[1];
                int grade = Integer.parseInt(tokens[2]);
                if (!scoreMap.containsKey(student)) {
                    scoreMap.put(student, new HashMap<>());
                }
                scoreMap.get(student).put(course, grade);
            }
            scanner.close();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
    }

    // 处理按钮点击事件
    public void actionPerformed(ActionEvent e) {
        if (e.getSource() == loginButton) {
            String user = userField.getText();
            String pass = new String(passField.getPassword());
            if (userMap.containsKey(user) && userMap.get(user).equals(pass)) {
                resultArea.setText("登录成功！");
            } else {
                resultArea.setText("用户名或密码错误！");
            }
        } else if (e.getSource() == addButton) {
            String course = courseField.getText();
            String student = studentField.getText();
            int grade = Integer.parseInt(gradeField.getText());
            if (!scoreMap.containsKey(student)) {
                scoreMap.put(student, new HashMap<>());
            }
            scoreMap.get(student).put(course, grade);
            resultArea.setText("添加成功！");
            saveData();
        } else if (e.getSource() == queryButton) {
            String student = studentField.getText();
            if (scoreMap.containsKey(student)) {
                StringBuilder sb = new StringBuilder();
                sb.append(student).append("的成绩：\n");
                Map<String, Integer> scores = scoreMap.get(student);
                for (Course course : courseList) {
                    String courseName = course.getName();
                    if (scores.containsKey(courseName)) {
                        sb.append(courseName).append(": ").append(scores.get(courseName)).append("\n");
                    }
                }
                resultArea.setText(sb.toString());
            } else {
                resultArea.setText("该学生不存在！");
            }
        } else if (e.getSource() == modifyButton) {
            String course = courseField.getText();
            String student = studentField.getText();
            int grade = Integer.parseInt(gradeField.getText());
            if (scoreMap.containsKey(student)) {
                Map<String, Integer> scores = scoreMap.get(student);
                if (scores.containsKey(course)) {
                    scores.put(course, grade);
                    resultArea.setText("修改成功！");
                    saveData();
                } else {
                    resultArea.setText("该学生未选修该课程！");
                }
            } else {
                resultArea.setText("该学生不存在！");
            }
        } else if (e.getSource() == deleteButton) {
            String course = courseField.getText();
            String student = studentField.getText();
            if (scoreMap.containsKey(student)) {
                Map<String, Integer> scores = scoreMap.get(student);
                if (scores.containsKey(course)) {
                    scores.remove(course);
                    resultArea.setText("删除成功！");
                    saveData();
                } else {
                    resultArea.setText("该学生未选修该课程！");
                }
            } else {
                resultArea.setText("该学生不存在！");
            }
        }
    }

    // 将数据保存到文件中
    private void saveData() {
        try {
            PrintWriter writer = new PrintWriter(new FileWriter("scores.txt"));
            for (String student : scoreMap.keySet()) {
                Map<String, Integer> scores = scoreMap.get(student);
                for (String course : scores.keySet()) {
                    writer.println(student + "," + course + "," + scores.get(course));
                }
            }
            writer.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    // 课程类
    private static class Course {
        private String name;
        private String teacher;

        public Course(String name, String teacher) {
            this.name = name;
            this.teacher = teacher;
        }

        public String getName() {
            return name;
        }

        public String getTeacher() {
            return teacher;
        }
    }

    public static void main(String[] args) {
        new ScoreManagementSystem().setVisible(true);
    }
}

以上代码实现了一个简单的学生成绩管理系统，带有图形界面，能够登录，能够录入、查询、修改、删除课程，能够录入、查询、修改、删除学生某个课程的成绩，能够持久化。