java后台模拟post请求上传图片

爱被打了一巴掌 2021-11-10 09:48 393阅读 0赞

public static JsonRtn<?> uploadImage(String filePath, String uploadUrl,String cookie) {
           
            File file = new File(filePath);
            if (!file.exists()) {
                return null;
            }
            String jsonStr = "";
            try {
                URL url1 = new URL(uploadUrl);
                HttpURLConnection conn = (HttpURLConnection) url1.openConnection();
                conn.setConnectTimeout(5000);
                conn.setReadTimeout(30000);
                conn.setDoOutput(true);
                conn.setDoInput(true);
                conn.setUseCaches(false);
                conn.setRequestMethod("POST");
                String boundary = "----WebKitFormBoundary" + createRandCode().substring(0, 16);
                conn.setRequestProperty("Content-Type", "multipart/form-data; boundary=" + boundary);
                conn.setRequestProperty("Cookie", cookie);
                OutputStream output = conn.getOutputStream();
                output.write(("--" + boundary + "\r\n").getBytes());
                output.write(String.format("Content-Disposition: form-data; name=\"file\"; filename=\"%s\"\r\n", file.getName()).getBytes());
                output.write("Content-Type: image/jpeg \r\n\r\n".getBytes());
                byte[] data = new byte[1024];
                int len = 0;
                FileInputStream input = new FileInputStream(file);
                while ((len = input.read(data)) > -1) {
                    output.write(data, 0, len);
                }
                output.write(("\r\n--" + boundary + "--").getBytes());
                output.flush();
                output.close();
                input.close();
                InputStream resp = conn.getInputStream();
                StringBuffer sb = new StringBuffer();
                while ((len = resp.read(data)) > -1)
                    sb.append(new String(data, 0, len, "utf-8"));
                resp.close();
                jsonStr = sb.toString();
                System.out.println(jsonStr);
              
            } catch (ClientProtocolException e) {
                logger.info(CLASS_NAME + "postFile，不支持http协议" + e.toString());
               
            } catch (IOException e) {
                logger.info("postFile数据传输失败" + e);
               
            }
        }
    
    
    
     /**
         * 获取一个随机字符串
         *
         * @return
         */
        private static String createRandCode() {
            char[] chars = new char[35];
            short start = '0';
            //如果此处没有加法，那么一个随机数取到1才会获得字符‘z’。所以此处+1即可，理论封顶是加到14，超过14就会取得其余字符，但我们通过了方法判断字符，不用担心！
            short end = 'z' + 14;
            for (int i = 0; i < chars.length; i++) {
                while (true) {
                    char orderNum = (char) (Math.random() * (end - start) + start);
                    if (Character.isLetter(orderNum) || Character.isDigit(orderNum)) {
                        chars[i] = orderNum;
                        /*System.out.println("orderNum:" + orderNum);*/
                        break;
                    }
                }
            }
            String str = new String(chars);
            return str;
        }

直接上代码，亲测有效！！！需要注意的地方是图片后台接收的名称需要修改，我这里后台接收的名称是file