java 导出数据格式为csv

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解决方案：

引入pom文件

<dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-csv</artifactId>
            <version>1.8</version>
</dependency>

示例代码：

@GetMapping("/N042")
public CommonResult N042(HttpServletResponse response, @RequestParam("qs") Date qs,
                         @RequestParam("zs") Date zs) {
    try (Connection conn = DriverManager.getConnection(url, username, password);
         CallableStatement cs = conn.prepareCall("{call PRO_N042(?,?)}");) {
        // 设置输入参数的值
        cs.setDate(1, qs);
        cs.setDate(2, zs);
        // 调用存储过程
        cs.execute();
        ResultSet resultSet = cs.executeQuery();

        // 创建CSV文件
        File csvFile = new File("N042.csv");
        FileWriter writer = new FileWriter(csvFile);
        CSVPrinter csvPrinter = new CSVPrinter(writer, CSVFormat.DEFAULT);

        // 获取ResultSet的元数据
        ResultSetMetaData metaData = resultSet.getMetaData();
        int columnCount = metaData.getColumnCount();

        // 将列名写入CSV文件
        for (int i = 1; i <= columnCount; i++) {
            csvPrinter.print(metaData.getColumnName(i));
        }
        csvPrinter.println();

        // 将数据写入CSV文件
        while (resultSet.next()) {
            for (int i = 1; i <= columnCount; i++) {
                csvPrinter.print(resultSet.getString(i));
            }
            csvPrinter.println();
        }

        csvPrinter.close();
        writer.close();

        // 设置响应头信息
        response.setContentType("text/csv");
        response.setHeader("Content-Disposition", "attachment; filename=\"" + csvFile.getName() + "\"");

        // 将CSV文件写入响应流中
        FileInputStream fileInputStream = new FileInputStream(csvFile);
        OutputStream outputStream = response.getOutputStream();
        byte[] buffer = new byte[1024];
        int bytesRead;
        while ((bytesRead = fileInputStream.read(buffer)) != -1) {
            outputStream.write(buffer, 0, bytesRead);
        }
        outputStream.flush();
        outputStream.close();
        fileInputStream.close();

        // 删除临时CSV文件
        csvFile.delete();

    } catch (SQLException | IOException e) {
        return CommonResult.error(e.getMessage());
    }
    return CommonResult.success();
}

这段代码使用了CSVPrinter和CSVFormat来创建和写入CSV文件。在将文件写入响应流之后，会删除临时的CSV文件。