Simple Client-Server Application for Android

This application is a simple client-server application which has a Android mobile client and a Java server which is run on a machine. In this example, client is run on the Android emulator and the server is run on the local host. In Android 10.0.2.2 is the IP address for local host. This application allow to type a text message on a text field and when the Send button is press the message is sent to the server. Server continuously listen to the port. When there is a incoming message server read it and show it on the standard output.



Client Side Application


SlimpleClientActivity.java

/*
 * This is a simple Android mobile client
 * This application read any string messege typed on the text field and 
 * send it to the server when the Send button is pressed
 * Author by Lak J Comspace
 */

package lakj.comspace.simpleclient;

import java.io.IOException;
import java.io.PrintWriter;
import java.net.Socket;
import java.net.UnknownHostException;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

public class SimpleClientActivity extends Activity {

 private Socket client;
 private PrintWriter printwriter;
 private EditText textField;
 private Button button;
 private String messsage;

 @Override
 public void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.main);

  textField = (EditText) findViewById(R.id.editText1); //reference to the text field
  button = (Button) findViewById(R.id.button1);   //reference to the send button

  //Button press event listener
  button.setOnClickListener(new View.OnClickListener() {

   public void onClick(View v) {

    messsage = textField.getText().toString(); //get the text message on the text field
    textField.setText("");      //Reset the text field to blank

    try {

     client = new Socket("10.0.2.2", 4444);  //connect to server
     printwriter = new PrintWriter(client.getOutputStream(),true);
     printwriter.write(messsage);  //write the message to output stream

     printwriter.flush();
     printwriter.close();
     client.close();   //closing the connection

    } catch (UnknownHostException e) {
     e.printStackTrace();
    } catch (IOException e) {
     e.printStackTrace();
    }
   }
  });

 }
}

/*
 * This is a simple server application
 * This server receive a string message from the Android mobile phone
 * and show it on the console.
 * Author by Lak J Comspace
 */
package simpleserver;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.ServerSocket;
import java.net.Socket;

public class Main {

    private static ServerSocket serverSocket;
    private static Socket clientSocket;
    private static InputStreamReader inputStreamReader;
    private static BufferedReader bufferedReader;
    private static String message;

    public static void main(String[] args) {

        try {
            serverSocket = new ServerSocket(4444);  //Server socket

        } catch (IOException e) {
            System.out.println("Could not listen on port: 4444");
        }

        System.out.println("Server started. Listening to the port 4444");

        while (true) {
            try {

                clientSocket = serverSocket.accept();   //accept the client connection
                inputStreamReader = new InputStreamReader(clientSocket.getInputStream());
                bufferedReader = new BufferedReader(inputStreamReader); //get the client message
                message = bufferedReader.readLine();

                System.out.println(message);
                inputStreamReader.close();
                clientSocket.close();

            } catch (IOException ex) {
                System.out.println("Problem in message reading");
            }
        }

    }
}

Judul: Simple Client-Server Application for Android
Ditulis oleh Unknown
Rating Blog 5 dari 5