使用HttpURLConnection项目间传输附件

首先获取文件

@PostMapping(value = "/uploadFile")
public Result<?> uploadFile(@RequestBody String jsonStr, HttpServletRequest request, HttpServletResponse response) {
	//创建封装的返回对象
	Result<?> result = new Result<>();
	//将请求的参数转为JSONObject对象
	JSONObject jsonObj = JSONObject.parseObject(jsonStr);
	//获取到相应的请求参数
	String orderId = String.valueOf(jsonObj.get("orderId"));
	String type = String.valueOf(jsonObj.get("type"));

	//解析请求的附件列表转为JSONArray
	JSONArray json  = JSONArray.parseArray(String.valueOf(jsonObj.get("fileList")));
	//定义返回的提示
	String resultVal = "上传成功";
	//获取另一个项目需要接收附件的地址
	RequestBaseUrl info = requestBaseUrlService.getInfo();
	//拼接地址和基础的请求参数(参数中不能出现中文，否则报错)
	String actionUrl = info.getUrl3() + "/predictOrderController.do?fileReceive&orderno=" + orderId + "&type=" + type;
	
	//循环JSONArray
	for (Object o : json) {
		Map<String, File> files = new HashMap<String, File>();
		//强转发为map
		Map map = (Map)o;

		//得到文件地址
		String filePath = uploadpath + File.separator + map.get("filePath").toString();
		File file = new File(filePath);

		//判断文件是否存在
		if(!file.exists()){
			response.setStatus(404);
			result.setMessage("保存失败");
			result.setSuccess(false);
			throw new RuntimeException("文件不存在..");
		} else {
			files.put(file.getName(), file);
		}

		try {
			//调用附件传输方法，得到返回值
			resultVal = upLoadFilePost(actionUrl, files);
			//判断结果，接收附件接口返回的是Boolean也会被转为String类型，所以使用equals判断即可
			if("true".equals(resultVal)) {
				//删除附件(这里可删可不删)
				file.delete();
			} else {
				resultVal = "上传失败";
				result.setSuccess(false);
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	 result.setMessage(resultVal);

     return result;
}

传输文件

public String upLoadFilePost(String actionUrl, Map<String, File> files) throws IOException {
	String BOUNDARY = java.util.UUID.randomUUID().toString();
	String PREFIX = "--", LINEND = "\r\n";
	String MULTIPART_FROM_DATA = "multipart/form-data";
	String CHARSET = "UTF-8";
	URL uri = new URL(actionUrl);
	HttpURLConnection conn = (HttpURLConnection) uri.openConnection();
	conn.setReadTimeout(15 * 1000);
	conn.setDoInput(true);// 允许输入
	conn.setDoOutput(true);// 允许输出
	conn.setUseCaches(false);
	conn.setRequestMethod("POST"); // Post方式
	conn.setRequestProperty("connection", "keep-alive");
	conn.setRequestProperty("Charsert", "UTF-8");
	conn.setRequestProperty("Content-Type", MULTIPART_FROM_DATA
			+ ";boundary=" + BOUNDARY);

	DataOutputStream outStream = new DataOutputStream(
			conn.getOutputStream());
	// 发送文件数据
	if (files != null)
		for (Map.Entry<String, File> file : files.entrySet()) {
			StringBuilder sb1 = new StringBuilder();
			sb1.append(PREFIX);
			sb1.append(BOUNDARY);
			sb1.append(LINEND);
			sb1.append("Content-Disposition: form-data; name=\"file\"; filename=\""
					+ file.getKey() + "\"" + LINEND);
			sb1.append("Content-Type: application/octet-stream; charset="
					+ CHARSET + LINEND);
			sb1.append(LINEND);
			outStream.write(sb1.toString().getBytes("utf-8"));	//getBytes()不加utf-8 传输中文名附件时，接收附件的地方解析文件名会乱码

			InputStream is = new FileInputStream(file.getValue());
			byte[] buffer = new byte[1024];
			int len = 0;
			while ((len = is.read(buffer)) != -1) {
				outStream.write(buffer, 0, len);
			}

			is.close();
			outStream.write(LINEND.getBytes());
		}

	// 请求结束标志
	byte[] end_data = (PREFIX + BOUNDARY + PREFIX + LINEND).getBytes();
	outStream.write(end_data);
	outStream.flush();

	// 得到响应码
	int res = conn.getResponseCode();
	if (res == 200) {
		InputStream in = conn.getInputStream();
		InputStreamReader isReader = new InputStreamReader(in);
		BufferedReader bufReader = new BufferedReader(isReader);
		String line = "";
		String data = "";
		while ((line = bufReader.readLine()) != null) {
			data += line;
		}
		outStream.close();
		conn.disconnect();
		return data;
	}
	//关闭流
	outStream.close();
	//关闭连接
	conn.disconnect();
	return null;
}

接收附件

@RequestMapping(params="fileReceive")
@ResponseBody
public Boolean fileInteraction(HttpServletRequest request, HttpServletResponse response) throws Exception {
	Boolean result = false;
    MultipartHttpServletRequest multiRequest = (MultipartHttpServletRequest) request;
	//解析request，将结果放置在list中
	Map<String, List<MultipartFile>> fileMap = multiRequest.getMultiFileMap();
	for (String key : fileMap.keySet()) {
		List<MultipartFile> files = fileMap.get(key);
		for (MultipartFile file : files) {
			if (!file.isEmpty()) {
				String fileNamePath = file.getOriginalFilename();
				String[] params = fileNamePath.split("\\.");
				String filename = "";
				int i = 0;
				for (String str : params) {
					i = i + 1;
					if (StringUtils.isNotEmpty(filename)) {
						if (i==params.length) {
							filename = filename + "." + str;
						}else{
							filename = filename + "/" + str;
						}
					}else{
						filename = str;
					}
				}
				 // 文件保存路径
				 String filePath = request.getSession().getServletContext().getRealPath("/") + "upload/wxfile/" + filename;
				 System.out.println(filePath);
				 File iFile = new File(filePath);
				 File iFileParent = iFile.getParentFile();
				 if(!iFileParent.exists()){
					 iFileParent.mkdirs();
				 }
				 // 转存文件
				 file.transferTo(new File(filePath));
				 result = true;

			 }
		}
	}
	return result;
}