Android Developers use GET to request and send data to servers

Android Developers use GET to request and send data to servers
#1. First, use a new servlet to process login requests

The Code is as follows. Only the doGet method is implemented.

package com.wzw.servlet;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;/** * Servlet implementation class LoginServlet */public class LoginServlet extends HttpServlet {private static final long serialVersionUID = 1L;           /**     * @see HttpServlet#HttpServlet()     */    public LoginServlet() {        super();        // TODO Auto-generated constructor stub    }/** * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response) */protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {String username=request.getParameter("username");String password=request.getParameter("password");if(username.equals("admin")&&password.equals("123456")){response.getWriter().println("success");}else{response.getWriter().println("failed");}}/** * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response) */protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {// TODO Auto-generated method stub}}

#2. In the android layout file, the layout is as follows: two input boxes and buttons

Added a click event on the button. #3. Implement the specific code in main_activity

Package com. wzw. submitdata; import com. wzw. submitdata. utils. netUtil; import android. OS. bundle; import android. app. activity; import android. view. menu; import android. view. view; import android. widget. editText; import android. widget. toast; public class MainActivity extends Activity {private EditText etUsername; private EditText etPassword; @ Overrideprotected void onCreate (Bundle savedInstanceState) {super. onCreate (savedInstanceState); setContentView (R. layout. activity_main); etUsername = (EditText) findViewById (R. id. et_username); etPassword = (EditText) findViewById (R. id. et_password);} public void doGet (View v) {final String username = etUsername. getText (). toString (); final String password = etPassword. getText (). toString (); new Thread (new Runnable () {@ Overridepublic void run () {// the access network needs to be implemented in the Child Thread. Use get to get data final String state = NetUtil. loginOfGet (username, password); // run the runOnUiThread (new Runnable () {public void run () {// operation on the main thread. The result Toast is displayed. makeText (MainActivity. this, state, 0 ). show ();}});}}). start ();}}

#4. Create another small tool class to access the network

Package com. wzw. submitdata. utils; import java. io. byteArrayOutputStream; import java. io. inputStream; import java.net. httpURLConnection; import java.net. malformedURLException; import java.net. URL; public class NetUtil {/*** use GET to access the network * @ param username * @ param password * @ return result returned by the server */public static String loginOfGet (String username, string password) {HttpURLConnection conn = null; try {String data = "use Rname = "+ username +" & password = "+ password; URL url = new URL (" http: // 192.168.1.4: 8080/AndroidServer/LoginServlet? "+ Data); conn = (HttpURLConnection) url. openConnection (); conn. setRequestMethod ("GET"); conn. setConnectTimeout (10000); conn. setreadtimeouts (5000); conn. connect (); int code = conn. getResponseCode (); if (code = 200) {InputStream is = conn. getInputStream (); String state = getStringFromInputStream (is); return state ;}} catch (Exception e) {e. printStackTrace ();} finally {if (conn! = Null) {conn. disconnect () ;}} return null;}/*** returns a String * @ param is * @ return * @ throws Exception */private static String getStringFromInputStream (InputStream is) based on the input stream) throws Exception {ByteArrayOutputStream baos = new ByteArrayOutputStream (); byte [] buff = new byte [1024]; int len =-1; while (len = is. read (buff ))! =-1) {baos. write (buff, 0, len);} is. close (); String html = baos. toString (); baos. close (); return html ;}}

In this way, you can request data from the server.