简单的android和本地服务器通信，以及乱码问题的解决

由于最近帮助一个学弟做了一个小的系统，需要用到客户端和服务器来实现通信的效果。然后我这边也是第一次做这样东西，所以我就把这几天遇到的问题在这里做下总结，也可以方便后面的网友们看看。

我们在通讯过程中客户端可以通过post和get两种方式来与服务端进行通信。我在这边就介绍下post方式吧。

1、客户端

public static JSONObject sendState(JSONObject json, String url) {InputStreamReader isr = null;DataOutputStream dos = null;HttpURLConnection urlConn = null;BufferedReader bufferedReader = null;JSONObject jsonObject = null;try {URL url1 = new URL(url);urlConn = (HttpURLConnection) url1.openConnection();urlConn.setDoInput(true);//设置输入流采用字节流urlConn.setDoOutput(true);//设置输出流采用字节流urlConn.setRequestMethod(\"POST\");//post方法urlConn.setUseCaches(false);//缓存urlConn.setReadTimeout(20000);urlConn.setConnectTimeout(20000);urlConn.setRequestProperty(\"Content-Type\", \"application/x-www-form-urlencoded\");//设置meta参数urlConn.setRequestProperty(\"Charset\", \"utf-8\");//缓存String data = json.toString();urlConn.connect();//连接服务器发送消息if(data!=null&&!\"\".equals(data)){dos = new DataOutputStream(urlConn.getOutputStream());dos.write((json.toString()).getBytes());//写数据dos.close();dos.flush();}if(urlConn.getResponseCode()==200){isr = new InputStreamReader(urlConn.getInputStream());bufferedReader = new BufferedReader(isr);String result = \"\";String readLine = null;while ((readLine = bufferedReader.readLine()) != null) {result += readLine;}jsonObject = new JSONObject(result);bufferedReader.close();isr.close();}urlConn.disconnect();//关闭连接return jsonObject;} catch (MalformedURLException e) {e.printStackTrace();return jsonObject;} catch (IOException e) {e.printStackTrace();return jsonObject;} catch (JSONException e) {e.printStackTrace();return jsonObject;}

我们可以将用来查询的Sql语句所需要的数据都存放到json中上传给服务器，例如登录功能，我们将用户名、密码写入json中。

2、服务端

public class Login extends HttpServlet{
private static final long serialVersionUID = 1L;

   /**
   * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
   */
   protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
       doPost(request, response);
   }

   /**
   * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
   */
   protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
       // 解决中文乱码
request.setCharacterEncoding(\”UTF-8\”);
response.setContentType(\”text/html;charset=UTF-8\”);
//response.setCharacterEncoding(\”UTF-8\”);
PrintWriter out = response.getWriter();
BufferedReader in = new BufferedReader(new InputStreamReader(
request.getInputStream(),\”utf-8\”));//这里很重要，中文乱码可以解决。
StringBuilder sb = new StringBuilder();
String line = null;
String result = \”\”;
JSONObject jsonObject = null;
while ((line = in.readLine()) != null) {
sb.append(line);
}
result = sb.toString();
jsonObject = JSONObject.fromObject(result);
String username = jsonObject.getString(\”username\”);
String password = jsonObject.getString(\”password\”);
UserServiceImpl impl = new UserServiceImpl();
boolean isExit = impl.queryUserForLogin(username, password);
Map<String, String> params = new HashMap<String, String>();
if(isExit) {
   params.put(\”result\”, \”success\”);
} else {
   params.put(\”result\”, \”fail\”);
}
JSONObject jsonObjec = JSONObject.fromObject(params);
out.write(jsonObjec.toString());
out.flush();
out.close();
   }
}