[Java知识库]FileNotFoundException (文件名、目录名或卷标语法不正确。)

excel转为流，进行下载。本地可以，服务器报：

java.io.FileNotFoundException: file:\E:\liziyi\guopei6\gp6-exam\target\gp6-exam-0.0.1-SNAPSHOT.jar!\BOOT-INF\classes!\exceltemplate\exam_record_import_template.xls (文件名、目录名或卷标语法不正确。)

因为服务器上是要打jar包，运行的。这时候再查询文件地址，会报错

 public String download(String fileName, String folder, HttpServletRequest request, HttpServletResponse response) {
        response.setCharacterEncoding("utf-8");
        response.setContentType("multipart/form-data");
        response.setHeader("Content-Disposition", "attachment;fileName=" + fileName);
        try {
            String path = this.getClass().getClassLoader().getResource(folder + "/" + fileName).getPath();
            InputStream inputStream = new FileInputStream(new File(path));
            OutputStream os = response.getOutputStream();
            byte[] b = new byte[2048];
            int length;
            while ((length = inputStream.read(b)) > 0) {
                os.write(b, 0, length);
            }
            // 这里主要关闭。
            os.close();

            inputStream.close();
        } catch (IOException e) {
            log.error(e.getMessage(), e);
        }
        return null;
    }

因为jar属于压缩包，所以要使用getResourceAsStream，不能使用getResource

public String download(String fileName, String folder, HttpServletRequest request, HttpServletResponse response) {
        response.setCharacterEncoding("utf-8");
        response.setContentType("multipart/form-data");
        response.setHeader("Content-Disposition", "attachment;fileName=" + fileName);
        try {
        InputStream inputStream = this.getClass().getClassLoader().getResourceAsStream(folder + "/" + fileName);
            OutputStream os = response.getOutputStream();
            byte[] b = new byte[2048];
            int length;
            while ((length = inputStream.read(b)) > 0) {
                os.write(b, 0, length);
            }
            // 这里主要关闭。
            os.close();

            inputStream.close();
        } catch (FileNotFoundException e) {
            log.error(e.getMessage(), e);
        } catch (IOException e) {
            log.error(e.getMessage(), e);
        }
        return null;
    }

待补充：

excel，先生成，再下载

excel使用多线程和redis下载文件