java mysql导出excel

import java.io.FileOutputStream;
import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import org.apache.poi.ss.usermodel.*;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

public class MySQLToExcel {
    public static void main(String[] args) {
        String url = "jdbc:mysql://localhost:3306/mydatabase";
        String user = "username";
        String password = "password";
        String sql = "SELECT * FROM mytable";

        try (Connection conn = DriverManager.getConnection(url, user, password);
             Statement stmt = conn.createStatement();
             ResultSet rs = stmt.executeQuery(sql)) {

            Workbook workbook = new XSSFWorkbook();
            Sheet sheet = workbook.createSheet("Data");

            // 创建表头
            Row headerRow = sheet.createRow(0);
            for (int i = 1; i <= rs.getMetaData().getColumnCount(); i++) {
                Cell cell = headerRow.createCell(i - 1);
                cell.setCellValue(rs.getMetaData().getColumnName(i));
            }

            // 填充数据
            int rowNum = 1;
            while (rs.next()) {
                Row row = sheet.createRow(rowNum++);
                for (int i = 1; i <= rs.getMetaData().getColumnCount(); i++) {
                    Cell cell = row.createCell(i - 1);
                    cell.setCellValue(rs.getString(i));
                }
            }

            // 写入文件
            try (FileOutputStream fileOut = new FileOutputStream("data.xlsx")) {
                workbook.write(fileOut);
            }

            System.out.println("数据已成功导出到 data.xlsx 文件中。");

        } catch (SQLException | IOException e) {
            e.printStackTrace();
        }
    }
}