關於調用第三方接口時傳遞參數是File類型的解決方式

最近在做一個項目，需要頻繁的調用第三方的接口，本以爲都是基本的數據類型，沒想到需要傳一個文件類型的參數，我想着調用接口的時候直接用文件流把文件寫到connection不就行了，這就是我一開始寫的調用工具類

    public static String sendGetFile(String url, MultipartFile file) {
        String result = "";
        BufferedReader in = null;
        try {
            URL realUrl = new URL(url);
            // 打開和URL之間的連接
            URLConnection connection = realUrl.openConnection();
            // 設置通用的請求屬性
            connection.setRequestProperty("accept", "*/*");
            connection.setRequestProperty("connection", "Keep-Alive");
            connection.setRequestProperty("user-agent",
                    "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
            // 建立實際的連接
            connection.connect();
            // 獲取所有響應頭字段
            Map<String, List<String>> map = connection.getHeaderFields();
            // 遍歷所有的響應頭字段
            for (String key : map.keySet()) {
                System.out.println(key + "--->" + map.get(key));
            }
            // 定義 BufferedReader輸入流來讀取URL的響應
            in = new BufferedReader(new InputStreamReader(
                    connection.getInputStream()));
            String line;
            while ((line = in.readLine()) != null) {
                result += line;
            }
        } catch (Exception e) {
            System.out.println("發送GET請求出現異常！" + e);
            e.printStackTrace();
        }
        // 使用finally塊來關閉輸入流
        finally {
            try {
                if (in != null) {
                    in.close();
                }
            } catch (Exception e2) {
                e2.printStackTrace();
            }
        }
        return result;
    }

沒想到報了文件損壞錯誤，改方法無用，改用form-data方式來傳數據方法如下

  public static String sendGetFile(String url, String filePath) {
        String sResponse="";
        try {
            CloseableHttpClient httpClient = HttpClients.createDefault();
            HttpPost uploadFile = new HttpPost(url);

            MultipartEntityBuilder builder = MultipartEntityBuilder.create();
            File f = new File(filePath);
            // 把文件加到HTTP的post請求中
            builder.addBinaryBody(
                    "code_file",
                    new FileInputStream(f),
                    ContentType.APPLICATION_OCTET_STREAM,
                    f.getName()
            );
            HttpEntity multipart = builder.build();
            uploadFile.setEntity(multipart);
            CloseableHttpResponse response = httpClient.execute(uploadFile);
            HttpEntity responseEntity = response.getEntity();
            sResponse  = EntityUtils.toString(responseEntity, "UTF-8");
        }catch (Exception e){
            e.printStackTrace();
        }
        return sResponse;
    }

結果成功!