/**	 * 採用get请求的方式	 * 	 * @param username	 * @param password	 * @return null表示求得的路径有问题,text返回请求得到的数据	 */	public static String getRequest(String username, String password) {		try {			String path = "http://172.22.64.156:8080/0001AndroidWebService/LoginServlet?username="					+ URLEncoder.encode(username)					+ "&password="					+ URLEncoder.encode(password);			URL url = new URL(path);			HttpURLConnection conn = (HttpURLConnection) url.openConnection();			conn.setReadTimeout(500);			conn.setRequestMethod("GET");			int code = conn.getResponseCode();			if (code == 200) {				// 请求成功				InputStream is = conn.getInputStream();				String text = StreamUtil.readStream(is);				return text;			} else {				// 请求失败				return null;			}		} catch (Exception e) {			e.printStackTrace();		}		return null;	}