Java通過POI將表數據導出爲Excel

前段時間項目需要將用戶操作日誌表導出爲Excel，上網搜了幾篇文章參考，最終實現了。這裏記錄下代碼，避免以後實現一樣的功能時再上網去搜。

導入以下兩個依賴：

<dependency>
    <groupId>org.apache.poi</groupId>
    <artifactId>poi</artifactId>
    <version>3.17</version>
</dependency>
<dependency>
    <groupId>org.apache.poi</groupId>
    <artifactId>poi-ooxml</artifactId>
    <version>3.17</version>
</dependency>

controller層：

@GetMapping("/export")
public void export(HttpServletResponse response) throws IOException {
    operationLogService.export(response);
}

service層：

public void export(HttpServletResponse response) throws IOException {
    HSSFWorkbook workbook = new HSSFWorkbook();
    //sheet名稱
    HSSFSheet sheet = workbook.createSheet("用戶操作日誌表");
    //獲取表數據，根據自己實際情況獲取
    List<OperationLog> logList = operationLogDao.listAll();
    //設置要導出的文件的名字
    String fileName = "用戶操作日誌" + ".xls";
    //新增數據行，並且設置單元格數據
    int rowNum = 1;
    String[] headers = {"id", "模塊", "姓名", "訪問時間", "IP地址", "操作內容"};
    //headers表示excel表中第一行的表頭
    HSSFRow row = sheet.createRow(0);
    //在excel表中添加表頭
    for (int i = 0; i < headers.length; i++) {
        HSSFCell cell = row.createCell(i);
        HSSFRichTextString text = new HSSFRichTextString(headers[i]);
        cell.setCellValue(text);
    }
    SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
    //在表中存放查詢到的數據放入對應的列
    for (OperationLog operationLog : logList) {
        HSSFRow row1 = sheet.createRow(rowNum);
        row1.createCell(0).setCellValue(operationLog.getId());
        row1.createCell(1).setCellValue(operationLog.getModule());
        row1.createCell(2).setCellValue(operationLog.getUserName());
        row1.createCell(3).setCellValue(format.format(operationLog.getLogTime()));
        row1.createCell(4).setCellValue(operationLog.getIp());
        row1.createCell(5).setCellValue(operationLog.getContent());
        rowNum++;
    }
    //設置自動列寬
    for (int i = 0; i < headers.length; i++) {
        sheet.autoSizeColumn(i);
        sheet.setColumnWidth(i, sheet.getColumnWidth(i) * 13 / 10);
    }
    response.setContentType("application/octet-stream;charset=UTF-8");
    response.setHeader("Content-Disposition", "attachment;filename=" + URLEncoder.encode(fileName, "utf-8"));
    workbook.write(response.getOutputStream());
}

最後直接用瀏覽器調即可。