技術標籤：txt文件匯出java 常用工具類java

匯出txt文件
學習地址：https://www.cnblogs.com/godtrue/p/6879594.html

   @GetMapping("/{id}/export")
    @ApiOperation("下載txt文件")
    public void exportText(HttpServletResponse response, @PathVariable(value = "id") @ApiParam(value = "主鍵id", example =
 
 "1", required = true) Integer id) {
       
        String jsonString = "2223";
        ExportTextUtil.writeToTxt(response, jsonString, "zsw");
    }

工具類

/**
 * 匯出檔案檔案的工具類
 */
@Slf4j
public class ExportTextUtil {


    /**
     * 匯出文字檔案
     *
     * @param response
     * @param jsonString
     * @param fileName
     */
 

    public static void writeToTxt(HttpServletResponse response, String jsonString, String fileName) {//設定響應的字符集
        response.setCharacterEncoding("utf-8");
        response.setContentType("text/plain");
        response.addHeader(
                "Content-Disposition"
 
,
                "attachment; filename="
                        + FileUtil.genAttachmentFileName(fileName + "_", "ZSW")
                        + MessageFormat.format("{0,date,yyyy-MM-dd}", new Object[]{Calendar.getInstance().getTime()})
                        + ".txt");//通過後綴可以下載不同的檔案格式
        BufferedOutputStream buff = null;
        ServletOutputStream outStr = null;
        try {
            outStr = response.getOutputStream();
            buff = new BufferedOutputStream(outStr);
            buff.write(delNull(jsonString).getBytes("UTF-8"));
            buff.flush();
            buff.close();
        } catch (Exception e) {
            log.error("匯出檔案檔案出錯，e:{}", e);
        } finally {
            try {
                buff.close();
                outStr.close();
            } catch (Exception e) {
                log.error("關閉流物件出錯 e:{}", e);
            }
        }
    }

    /**
     * 如果字串物件為 null，則返回空字串，否則返回去掉字串前後空格的字串
     *
     * @param str
     * @return
     */
    public static String delNull(String str) {
        String returnStr = "";
        if (StringUtils.isNotBlank(str)) {
            returnStr = str.trim();
        }
        return returnStr;
    }
}

@Slf4j
public class FileUtil {

    public static void writeCsv(HttpServletResponse httpServletResponse, String fileName, List<String> header, List<List<String>> columns) {

        httpServletResponse.setContentType("application/octet-stream;charset=utf-8");
        httpServletResponse.setHeader("Content-Disposition", "attachment; filename=\"" + URLUtil.encode(fileName, "UTF-8") + "\"");
        List<List<String>> rowList = new ArrayList<>();
        rowList.add(header);
        rowList.addAll(columns);
        final CsvWriter writer;
        try {
            writer = CsvUtil.getWriter(httpServletResponse.getWriter());
        } catch (IOException e) {
            log.error("IO error", e);
            throw new CustomizeException(BaseResultCode.FAIL_IO);
        }
        writer.write(rowList);
    }

    /**
     * 生成匯出附件中文名。應對匯出檔案中文亂碼
     * <p>
     * response.addHeader("Content-Disposition", "attachment; filename=" + cnName);
     *
     * @param cnName
     * @param defaultName
     * @return
     */
    public static String genAttachmentFileName(String cnName, String defaultName) {
        try {
            cnName = new String(cnName.getBytes("gb2312"), "ISO8859-1");
        } catch (Exception e) {
            cnName = defaultName;
        }
        return cnName;
    }
}