GUI 学生成绩管理系统

以下是一个基于Java Swing的GUI学生成绩管理系统的示例：

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

public class GradeManagementSystem extends JFrame implements ActionListener {
    private JTextField filePathField;
    private JTextArea resultArea;
    private JButton importButton;
    private JButton analyzeButton;
    private JButton sortButton;
    private JButton exportButton;

    private ArrayList<Integer> grades = new ArrayList<Integer>();

    public GradeManagementSystem() {
        super("学生成绩管理系统");

        // 设置窗口大小和位置
        setSize(600, 400);
        setLocationRelativeTo(null);

        // 设置窗口关闭时的操作
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        // 创建组件
        JLabel filePathLabel = new JLabel("文件路径：");
        filePathField = new JTextField(20);
        importButton = new JButton("导入");
        analyzeButton = new JButton("分析");
        sortButton = new JButton("排序");
        exportButton = new JButton("导出");
        resultArea = new JTextArea(10, 40);

        // 设置组件的事件监听器
        importButton.addActionListener(this);
        analyzeButton.addActionListener(this);
        sortButton.addActionListener(this);
        exportButton.addActionListener(this);

        // 添加组件到窗口中
        JPanel panel = new JPanel();
        panel.add(filePathLabel);
        panel.add(filePathField);
        panel.add(importButton);
        panel.add(analyzeButton);
        panel.add(sortButton);
        panel.add(exportButton);
        add(panel, BorderLayout.NORTH);
        add(new JScrollPane(resultArea), BorderLayout.CENTER);

        // 显示窗口
        setVisible(true);
    }

    // 处理按钮点击事件
    public void actionPerformed(ActionEvent e) {
        if (e.getSource() == importButton) {
            // 导入文件
            String filePath = filePathField.getText();
            try {
                BufferedReader reader = new BufferedReader(new FileReader(filePath));
                String line;
                while ((line = reader.readLine()) != null) {
                    grades.add(Integer.parseInt(line));
                }
                reader.close();
                resultArea.setText("成功导入 " + grades.size() + " 条数据");
            } catch (IOException ex) {
                resultArea.setText("导入失败：" + ex.getMessage());
            }
        } else if (e.getSource() == analyzeButton) {
            // 分析数据
            if (grades.size() == 0) {
                resultArea.setText("请先导入数据");
                return;
            }
            int sum = 0;
            int max = grades.get(0);
            int min = grades.get(0);
            for (int grade : grades) {
                sum += grade;
                if (grade > max) {
                    max = grade;
                }
                if (grade < min) {
                    min = grade;
                }
            }
            double average = (double) sum / grades.size();
            double variance = 0;
            for (int grade : grades) {
                variance += (grade - average) * (grade - average);
            }
            double standardDeviation = Math.sqrt(variance / grades.size());
            resultArea.setText("最高分：" + max + "\n最低分：" + min + "\n平均分：" + average + "\n标准差：" + standardDeviation);
        } else if (e.getSource() == sortButton) {
            // 排序数据
            if (grades.size() == 0) {
                resultArea.setText("请先导入数据");
                return;
            }
            Collections.sort(grades);
            resultArea.setText("排序结果：\n");
            for (int grade : grades) {
                resultArea.append(grade + "\n");
            }
        } else if (e.getSource() == exportButton) {
            // 导出数据
            if (grades.size() == 0) {
                resultArea.setText("请先导入数据");
                return;
            }
            String filePath = filePathField.getText();
            int dotIndex = filePath.lastIndexOf(".");
            String outputFilePath = filePath.substring(0, dotIndex) + ".xls";
            try {
                BufferedWriter writer = new BufferedWriter(new FileWriter(outputFilePath));
                for (int grade : grades) {
                    writer.write(grade + "\t");
                }
                writer.close();
                resultArea.setText("成功导出数据到 " + outputFilePath);
            } catch (IOException ex) {
                resultArea.setText("导出失败：" + ex.getMessage());
            }
        }
    }

    public static void main(String[] args) {
        new GradeManagementSystem();
    }
}