Implementation of Echo Server and Client Using TCP

/* Implementation of Echo Server and Client Using TCP */

// EchoServer.java : A Simple Echo Server Program

import java.io.*;

import java.net.*;

public class EchoServer

{

public static void main(String args[]) throws Exception

{

try

{

int Port;

BufferedReader Buf =new BufferedReader(new

InputStreamReader(System.in));

System.out.print(" Enter the Port Address : " );

Port=Integer.parseInt(Buf.readLine());

ServerSocket sok =new ServerSocket(Port);

System.out.println(" Server is Ready To Receive a Message. ");

System.out.println(" Waiting ..... ");

Socket so=sok.accept();

if(so.isConnected()==true)

            System.out.println(" Client Socket is Connected Succecfully. ");

InputStream in=so.getInputStream();

OutputStream ou=so.getOutputStream();

PrintWriter pr=new PrintWriter(ou);

BufferedReader buf=new BufferedReader(new

InputStreamReader(in));

String str=buf.readLine();

System.out.println(" Message Received From Client : " + str);

System.out.println(" This Message is Forwarded To Client. ");

pr.println(str);

pr.flush();

}

 catch(Exception e)

  {

  System.out.println(" Error : " + e.getMessage());

  }

}

}

// EchoClient.java: A Simple Echo Client Program

import java.io.*;

import java.net.*;

public class EchoClient

{

public static void main(String args[]) throws Exception

{

try {

int Port;

BufferedReader Buf =new BufferedReader(new

InputStreamReader(System.in));

System.out.print(" Enter the Port Address : " );

Port=Integer.parseInt(Buf.readLine());

Socket sok=new Socket("localhost",Port);

if(sok.isConnected()==true)

            System.out.println(" Server Socket is Connected Succecfully. ");

InputStream in=sok.getInputStream();

OutputStream ou=sok.getOutputStream();

PrintWriter pr=new PrintWriter(ou);

BufferedReader buf1=new BufferedReader(new

InputStreamReader(System.in));

BufferedReader buf2=new BufferedReader(new

InputStreamReader(in));

String str1,str2;

System.out.print(" Enter the Message : ");

str1=buf1.readLine();

pr.println(str1);

pr.flush();

System.out.println(" Message Send Successfully. ");

str2=buf2.readLine();

System.out.println(" Message From Server : " + str2);

     }

  catch(Exception e)

  {

   System.out.println(" Error : " + e.getMessage());

  }

}

}

OUTPUT :

EchoServer.java :

javac EchoServer.java

java     EchoServer

 Enter the Port Address : 1234

 Server is Ready To Receive a Message.

 Waiting .....

 Client Socket is Connected Succecfully.

 Message Received From Client : Welcome To JCE

 This Message is Forwarded To Client.

EchoClient.java :

javac EchoClient.java

java     EchoClient

 Enter the Port Address : 1234

 Server Socket is Connected Succecfully.

 Enter the Message : Welcome To JCE

 Message Send Successfully.

 Message From Server : Welcome To JCE

Implementation of Socket Programming Using UDP

/* Implementation of Socket Programming Using UDP */

// UDPServer.java : A Simple UDP Server Program

import java.io.*;

import java.net.*;

import java.util.*;

public class UDPServer

{

public static void main(String args[]) throws Exception

 {

try

  {

Date d = new Date();

byte[] Message = d.toString().getBytes();

int Port;

BufferedReader Buf =new BufferedReader(new

InputStreamReader(System.in));

System.out.print(" Enter the Port Address : " );

Port=Integer.parseInt(Buf.readLine());

DatagramSocket ds = new DatagramSocket(4343);

DatagramPacket dp = new DatagramPacket(Message,

Message.length,InetAddress.getLocalHost(),Port);

ds.send(dp);

System.out.println(" Message Send Successfully. ");    

ds.close();

   }

catch(Exception e)

  {

              System.out.println(" Error : " + e.getMessage());

  }

 }

}

//  UDPClient.java : A Simple UDP Client Program

import java.net.*;

import java.util.*;

import java.io.*;

public class UDPClient

{

public static void main(String args[]) throws IOException

 {

try

  {

byte Message[] = new byte[2024];

int Port;

BufferedReader Buf =new BufferedReader(new

InputStreamReader(System.in));

System.out.print(" Enter the Port Address : " );

Port=Integer.parseInt(Buf.readLine());

DatagramSocket ds = new DatagramSocket(Port);

System.out.println(" Client is Ready To Receive a Message. ");

System.out.println(" Waiting ..... ");

DatagramPacket dp = new

DatagramPacket(Message,Message.length);

ds.receive(dp);

byte[] info=dp.getData();

System.out.println(" Message Received From Server. ");

//  System.out.println(" The Current Server Time is : " + new

String(dp.getData(),0,dp.getLength()));  

System.out.println(" The Current Server Time is : " + new

String(info,0,dp.getLength()));

ds.close();

  }

catch(Exception e)

  {

              System.out.println(" Error : " + e.getMessage());

  }

 }

}

OUTPUT :

UDPServer.java :

javac UDPServer.java

java     UDPServer

 Enter the Port Address : 1234

 Message Send Successfully.

UDPClient.java :

javac UDPClient.java

java     UDPClient

 Enter the Port Address : 1234

 Client is Ready To Receive a Message.

 Waiting .....

 Message Received From Server.

 The Current Server Time is : Thu Sep 02 20:46:14 IST 2010

Implementation of Socket Programming Using TCP

/* Implementation of Socket Programming Using TCP */

            //  TCPServer.java : A Simple TCP Server Program

            import java.net.*;

            import java.util.*;

            import java.io.*;

            public class TCPServer

            {

public static void main(String args[]) throws IOException

            {

            try

            {

            int Port;

BufferedReader Buf =new BufferedReader(new

InputStreamReader(System.in));

            System.out.print(" Enter the Port Address : " );

            Port=Integer.parseInt(Buf.readLine());

            ServerSocket ss = new ServerSocket(Port);

            System.out.println(" Wait Client Socket is Connecting ..... ");

            Socket s=ss.accept();

            if(s.isConnected()==true)

            System.out.println(" Client Socket is Connected Succecfully. ");

            OutputStream out = s.getOutputStream();

            PrintWriter p=new PrintWriter(out);

            Date d=new Date();

            p.print(" Current Server Time is : " + d);

            p.flush();

            out.close();

            System.out.println(" Message send Successfully. " );

            }

            catch(Exception e)

                        {

                                      System.out.println(" Error : " + e.getMessage());

                          }

              }

            }

            // TCPClient.java : A simple TCP Client Program

            import java.net.*;

            import java.io.*;

           

            public class TCPClient

            {

            public static void main(String args[]) throws IOException

             {

            try

              {

            int Port;

            BufferedReader Buf =new BufferedReader(new

InputStreamReader(System.in));

            System.out.print(" Enter the Port Address : " );

            Port=Integer.parseInt(Buf.readLine());

            Socket s = new Socket("localhost",Port);

            if(s.isConnected()==true)

            System.out.println(" Server Socket is Connected Succecfully. ");

            InputStream in = s.getInputStream();

            BufferedReader buf=new BufferedReader(new

InputStreamReader(in));

            String str = buf.readLine();

            System.out.println(" Message Received From Server. " );

            System.out.println(str);

            in.close();

            s.close();

               }

            catch(Exception e)

                        {

                              System.out.println(" Error : " + e.getMessage());

                        }

             }

            }

OUTPUT :

TCPServer.java :

javac TCPServer.java

java     TCPServer

 Enter the Port Address : 1234

 Wait Client Socket is Connecting .....

 Client Socket is Connected Succecfully.

 Message send Successfully.

TCPClient.java :

javac TCPClient.java

java     TCPClient

 Enter the Port Address : 1234

 Server Socket is Connected Succecfully.

 Message Received From Server.

 Current Server Time is : Thu Sep 02 19:37:48 IST 2010