HttpUrlConnection支持Header,Body传值，支持Multipart上传文件

 Http请求之基于HttpUrlConnection，支持Header,Body传值，支持Multipart上传文件：

public static String post(String actionUrl, Map<String, String> headParams,Map<String, String> params,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(30 * 1000); // 缓存的最长时间conn.setDoInput(true);// 允许输入conn.setDoOutput(true);// 允许输出conn.setUseCaches(false); // 不允许使用缓存conn.setRequestMethod("POST");conn.setRequestProperty("connection", "keep-alive");conn.setRequestProperty("Charsert", "UTF-8");conn.setRequestProperty("Content-Type", MULTIPART_FROM_DATA+ ";boundary=" + BOUNDARY);if(headParams!=null){for(String key : headParams.keySet()){conn.setRequestProperty(key, headParams.get(key));}}StringBuilder sb = new StringBuilder();if (params!=null) {// 首先组拼文本类型的参数for (Map.Entry<String, String> entry : params.entrySet()) {sb.append(PREFIX);sb.append(BOUNDARY);sb.append(LINEND);sb.append("Content-Disposition: form-data; name=\""+ entry.getKey() + "\"" + LINEND);sb.append("Content-Type: text/plain; charset=" + CHARSET + LINEND);sb.append("Content-Transfer-Encoding: 8bit" + LINEND);sb.append(LINEND);sb.append(entry.getValue());sb.append(LINEND);}}DataOutputStream outStream = new DataOutputStream(conn.getOutputStream());if (!TextUtils.isEmpty(sb.toString())) {outStream.write(sb.toString().getBytes());}// 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());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);Log.i("HttpUtil", "写入中...");}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();Log.i("HttpUtil", "conn.getContentLength():"+conn.getContentLength());// 得到响应码int res = conn.getResponseCode();InputStream in = conn.getInputStream();if (res == 200) { BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(in, "UTF-8"));         StringBuffer buffer = new StringBuffer();       String line = "";       while ((line = bufferedReader.readLine()) != null){         buffer.append(line);       }  //int ch;//StringBuilder sb2 = new StringBuilder();//while ((ch = in.read()) != -1) {//sb2.append((char) ch);//}return buffer.toString();}outStream.close();conn.disconnect();return in.toString();}