java实现文件下载功能

java实现文件下载功能 根据图片地址下载图片至本地 并上传至oss

/** * 单个文件下载 * * @param fileName 单个文件名 * @throws Exception */
    @Override
    public void downOneFile(String fileName) throws Exception { 
   
        HttpServletResponse resp = ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes()).getResponse();
        File file = new File(FILE_ROOT_PATH + fileName);
        if (file.exists()) { 
   
            resp.setContentType("application/x-msdownload");
            resp.setHeader("Content-Disposition", "attachment;filename=" + new String(fileName.getBytes(), "ISO-8859-1"));
            InputStream inputStream = new FileInputStream(file);
            ServletOutputStream ouputStream = resp.getOutputStream();
            byte b[] = new byte[1024];
            int n;
            while ((n = inputStream.read(b)) != -1) { 
   
                ouputStream.write(b, 0, n);
            }
            ouputStream.close();
            inputStream.close();
        }
    }

 /** * 文件批量打包下载 * * @param fileNameList 多个文件名，用英文逗号分隔开 * @throws IOException */
    @Override
    public void downTogetherAndZip(List<String> fileNameList) throws IOException { 
   
        HttpServletResponse resp = ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes()).getResponse();
        resp.setContentType("application/x-msdownload");
        //暂时设定压缩下载后的文件名字为test.zip
        resp.setHeader("Content-Disposition", "attachment;filename=test.zip");
        String str = "";
        String rt = "\r\n";
        ZipOutputStream zos = new ZipOutputStream(resp.getOutputStream());
        for (String filename : fileNameList) { 
   
            str += filename + rt;
            File file = new File(FILE_ROOT_PATH + filename);
            zos.putNextEntry(new ZipEntry(filename));
            FileInputStream fis = new FileInputStream(file);
            byte b[] = new byte[1024];
            int n = 0;
            while ((n = fis.read(b)) != -1) { 
   
                zos.write(b, 0, n);
            }
            zos.flush();
            fis.close();
        }
        //设置解压文件后的注释内容
        zos.setComment("download success:" + rt + str);
        zos.flush();
        zos.close();
    }

将网络图片下载到本地并上传至阿里云oss

   public String uploadImg(Integer customerId, CustomerImageType customerImageType, String imageUrl) { 
   
        if (StringUtils.isEmpty(imageUrl)) { 
   
            return null;
        }
        //获取图片类型
        String imgFormat = imgFormat(imageUrl);
        //拼接图片名称
        String name = MxcUtils.tagImageFileName(customerId, customerImageType) + "." + imgFormat;
        //存储路径
        String path = ApiConstants.ID_CARD_PHOTO_PATH;
        if (customerImageType.equals(CustomerImageType.ID_CARD_FRONT)) { 
   
            path = ApiConstants.ID_CARD_PHOTO_PATH;
        }
        if (customerImageType.equals(CustomerImageType.PAN)) { 
   
            path = ApiConstants.PAN_PHOTO_PATH;
        }
        if (customerImageType.equals(CustomerImageType.FACE_IMAGE)) { 
   
            path = ApiConstants.FACES_PHOTO_PATH;
        }
        try { 
   
            URL url = new URL(imageUrl);
            HttpURLConnection huc = (HttpURLConnection) url.openConnection();
            //从HTTP响应消息获取状态码
            int code = huc.getResponseCode();
            if (code == 200) { 
   
                //获取输入流
                InputStream ips = huc.getInputStream();
                byte[] buffer = new byte[1024];
                int len = 0;
                ByteArrayOutputStream bos = new ByteArrayOutputStream();
                while ((len = ips.read(buffer)) != -1) { 
   
                    bos.write(buffer, 0, len);
                }
                bos.close();
                //下载到本地
                String filePath = uploadFileByBytes(bos.toByteArray(), name);
                File files = new File(filePath);
                InputStream inputStream = new FileInputStream(files);
                //上传文件至oss
                String respath = fileUploadOss(name, path, inputStream);
                //清除本地文件
                files.delete();
                return respath;
            }
            return "";
        } catch (Exception e) { 
   
            return "";
        }
    }

    /** * 将图片储存到 本地 * * @param bytes * @param fileName * @return * @throws Exception */
    private String uploadFileByBytes(byte[] bytes, String fileName) throws Exception { 
   
        for (int i = 0; i < bytes.length; i++) { 
   
            if (bytes[i] < 0) { 
   
                bytes[i] += 256;
            }
        }
        String realPath = System.getProperty("user.dir") + File.separator + "upload" + File.separator;
        //文件路径
        String url = realPath + fileName;
        //判断文件路径是否存在，如果没有则新建文件夹
        File files = new File(realPath);
        if (!files.exists()) { 
   
            files.mkdirs();
        }
        //把文件写入到指定路径下
        try (OutputStream out = new BufferedOutputStream(new FileOutputStream(url, false))) { 
   
            out.write(bytes);
        }
        return url;
    }

    /** * 上传阿里云 * * @param saveName 文件名 * @param savePath 路径 * @param inputStream 流 * @return url */
    private String fileUploadOss(String saveName, String savePath, InputStream inputStream) { 
   

        try { 
   
            aliyunOSSClient.uploadObject2OSS(saveName, inputStream, savePath);
            return aliyunOSSClient.getUrl(aliOssConfig.getBaseDir() + savePath + saveName);
        } catch (Exception e) { 
   
            log.error("文件上传oss失败!");
            e.printStackTrace();
        }
        return null;
    }


    public String imgFormat(String path) { 
   
        String imgFormat = "jpg";
        if (path.contains("bmp")) { 
   
            imgFormat = "bmp";
        }
        if (path.contains("png")) { 
   
            imgFormat = "png";
        }
        if (path.contains("tif")) { 
   
            imgFormat = "tif";
        }
        if (path.contains("gif")) { 
   
            imgFormat = "gif";
        }
        if (path.contains("pcx")) { 
   
            imgFormat = "pcx";
        }
        if (path.contains("tga")) { 
   
            imgFormat = "tga";
        }
        if (path.contains("exif")) { 
   
            imgFormat = "exif";
        }
        if (path.contains("fpx")) { 
   
            imgFormat = "fpx";
        }
        if (path.contains("svg")) { 
   
            imgFormat = "svg";
        }
        if (path.contains("psd")) { 
   
            imgFormat = "psd";
        }
        if (path.contains("cdr")) { 
   
            imgFormat = "cdr";
        }
        if (path.contains("pcd")) { 
   
            imgFormat = "pcd";
        }
        if (path.contains("dxf")) { 
   
            imgFormat = "dxf";
        }
        if (path.contains("ufo")) { 
   
            imgFormat = "ufo";
        }
        if (path.contains("eps")) { 
   
            imgFormat = "eps";
        }
        if (path.contains("ai")) { 
   
            imgFormat = "ai";
        }
        if (path.contains("raw")) { 
   
            imgFormat = "raw";
        }
        if (path.contains("WMF")) { 
   
            imgFormat = "WMF";
        }
        if (path.contains("webp")) { 
   
            imgFormat = "webp";
        }
        if (path.contains("avif")) { 
   
            imgFormat = "avif";
        }
        if (path.contains("apng")) { 
   
            imgFormat = "apng";
        }
        if (path.contains("apng")) { 
   
            imgFormat = "apng";
        }
        if (path.contains("JPEG")) { 
   
            imgFormat = "JPEG";
        }
        return imgFormat;
    }