Android uses okHttp (get method) to log in

package .;

import ;

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/**
 * Created by Administrator on 2016-03-27.
 */
public class HttpUtils {

  OkHttpClient client = new OkHttpClient();
  public static final MediaType JSON
      = ("application/json; charset=utf-8");

  public String login(String url, String json) throws IOException {
    //Convert the requested content string to json    RequestBody body = (JSON, json);
    //RequestBody formBody = new FormEncodingBuilder()

    Request request = new ()
        .url(url)
        .post(body)
        .build();

    Response response = (request).execute();

    String result = ().string();


    return result;


  }


  public String bolwingJson(String username, String password) {
    return "{'username':" + username + "," + "'password':" + password + "}";
    //   "{'username':" + username + ","+"'password':"+password+"}";
  }


} 

package .okhttpdemo3post;

import .;
import ;
import ;
import ;
import ;
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import .;

import org.;

import ;

public class MainActivity extends AppCompatActivity implements  {
  private static final String TAG ="MainActivity" ;
  //username  private EditText mEtUsername;
  //password  private EditText mEtPwd;
  //Login button  private Button mBtnLogin;
  private TextView mTvResult;

  private String url ="http://192.168.1.102:8080/Login/login";

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    (savedInstanceState);
    setContentView(.activity_main);

    initView();
    initListener();
  }

  /**
    * Initialize the component
    */
  private void initView() {

    mEtUsername = (EditText) findViewById(.login_et_name);
    mEtPwd = (EditText) findViewById(.login_et_pwd);

    mBtnLogin = (Button) findViewById(.login_btn_login);


    mTvResult = (TextView) findViewById(.login_tv_result);

  }

  /**
    * Set up the listener
    */
  private void initListener() {

    (this);


  }

  /*
   Click event listening
    */
  @Override
  public void onClick(View v) {
    if(v==mBtnLogin){
      login();
    }
  }

  /*
   Log in
    */
  private void login() {

    final String username = ().toString().trim();
    final String password = ().toString().trim();


    if((username) || (password)){

      (, "Username or password cannot be empty", Toast.LENGTH_SHORT).show();
      return;
    }

    new Thread(){
      @Override
      public void run() {

          HttpUtils httpUtils = new HttpUtils();
          //Convert to JSON          String user = (username, password);



        //String user ="{'username':" + username + ","+"'password':"+password+"}";

        (TAG, "user:" + user);

        try {
          final String result = (url, user);
          (TAG, "result:" + result);
          //Update the UI, in the UI thread          runOnUiThread(new Runnable() {
            @Override
            public void run() {
              if("SUCCESS".equals(result)){

                ("Login successfully");

              }else{
                ("Login failed");
              }
            }
          });
        } catch (IOException e) {
          ();
        }




      }
    }.start();


  }
}