package com.example.test;

public class AndroidTestActivity extends Activity {

    JSONArray jArray;

    String result = null;

    InputStream is = null;

    StringBuilder sb = null;

    public static final String HTTPCustomer ="http://192.168.1.102:8080/SevletTest/AndroidServlet"; 

    @Override

    public void onCreate(Bundle savedInstanceState) {

       super.onCreate(savedInstanceState);

       setContentView(R.layout.main);

       Button b1 = (Button) findViewById(R.id.button1);

       b1.setOnClickListener(new Button.OnClickListener() {

           @Override

           public void onClick(View v) {

              // TODO Auto-generated method stub

              EditText tv = (EditText) findViewById(R.id.editView);

              // http get

              try {

//                 HttpParams httpParameters = new BasicHttpParams(); 

//                  HttpConnectionParams.setConnectionTimeout(httpParameters, 5000); 

//                  HttpConnectionParams.setSoTimeout(httpParameters, 5000); 

//                  HttpConnectionParams.setTcpNoDelay(httpParameters, true);

                  HttpClient httpclient = new DefaultHttpClient();

                  HttpGet httpget = new HttpGet(HTTPCustomer);

                  HttpResponse response = httpclient.execute(httpget);

                  int status = response.getStatusLine().getStatusCode();

                  System.out.println("status="+status);

                  result = EntityUtils.toString(response.getEntity(), "UTF-8");

              } catch (Exception e) {

                  e.printStackTrace();

              }

              try {

                Gson gson = new Gson();

                List names = gson.fromJson(result, new TypeToken>(){}.getType());

                StringBuffer str = new StringBuffer();

                for(String name:names){

                   str.append(name);

                }

                tv.setText(str);

              }catch (Exception e) {

                  e.printStackTrace();

              }

           }

       });

    }

}

import java.io.BufferedReader;

import java.io.File;

import java.io.IOException;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.io.PrintWriter;

import java.sql.DriverManager;

import java.sql.ResultSet;

import java.text.SimpleDateFormat;

import java.util.ArrayList;

import java.util.Collections;

import java.util.Date;

import java.util.List;

import javax.servlet.ServletException;

import javax.servlet.annotation.WebServlet;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.google.gson.Gson;

import com.mysql.jdbc.Connection;

import com.mysql.jdbc.Statement;

@WebServlet("/AndroidServlet")

public class AndroidServlet extends HttpServlet {

         private static final long serialVersionUID = 1L;

         static String driver = "com.mysql.jdbc.Driver";

         static String url = "jdbc:mysql://localhost:3306/testdb";

         static String user = "username";

         static String password = "password";

    public AndroidServlet() {

        super();

        // TODO Auto-generated constructor stub

    }

         protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

                   // TODO Auto-generated method stub

                   request.setCharacterEncoding("UTF-8");

        response.setCharacterEncoding("UTF-8");

        response.setContentType("application/json;charset=utf-8");

        List resultList = null;

                   try {

                            resultList = getData();

                   } catch (Exception e) {

                            // TODO Auto-generated catch block

                            e.printStackTrace();

                   }

        Gson gson = new Gson();

        String result = gson.toJson(resultList);

        PrintWriter out = response.getWriter();

//        }

        out.write(result);

        out.flush();

        out.close();

         }

    private List getData() throws Exception {

        List resultList = new ArrayList();

                   Class.forName(driver);

                   Connection conn = (Connection) DriverManager.getConnection(url, user, password);

                   Statement statement = (Statement) conn.createStatement();

                   String sql = null;

                   sql = "select name from teacher";

                   ResultSet rs = statement.executeQuery(sql);

                   while(rs.next()){

                            resultList.add(rs.getString("name"));

                   }

        return resultList;

    }

         protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

                   // TODO Auto-generated method stub

         }

}