network programs

/*PROGRAM USING TCP SOCKET*/

SOURCE CODE:

SERVER PROGRAM:

import java.io.*;

import java.net.*;

class TCPServer

{

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

{

String fromclient;

String toclient;

ServerSocket Server=new ServerSocket(5000);

System.out.println("TCP server waiting for client on port     5000");

while(true)

{

Socket connected=Server.accept();

System.out.println("THE CLIENT"+" +connected.getInetAddress()+":"+connected.

getPort()+"IS CONNECTED");

BufferedReader inFromUser=new BufferedReader(new InputStreamReader(System.in));

BufferedReader inFromClient=new BufferedReader(new InputStream

Reader(connected.getInputStream()));

PrintWriter outToClient=new PrintWriter (connected.getOutputStream(),true);

while(true)

{

System.out.println("SEND(Type Q or q to Quit):");

toclient=inFromUser.readLine();

if(toclient.equals("q")||toclient.equals("Q"))

{

outToClient.println(toclient);

connected.close();

break;

}

else

outToClient.println(toclient);

fromclient=inFromClient.readLine();                                          if(fromclient.equals("q")||fromclient.equals("Q"))

{

connected.close();

break;

}

else

System.out.println("RECEIVED:"+fromclient);

}

}

}

}

CLIENT PROGRAM:

import java.io.*;

import java.net.*;

class TCPClients

{

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

{

String FromServer;

String ToServer;

Socket ClientSocket=new Socket("localhost",5000);

BufferedReader inFromUser=new BufferedReader(new InputStreamReader(System.in));

PrintWriter outToServer=new PrintWriter(Client

Socket.getOutputStream(),true);

BufferedReader inFromServer=new BufferedReader(new InputStream

Reader(ClientSocket.getInputStream()));

while(true)

{

FromServer=inFromServer.readLine();

if(FromServer.equals("q")||FromServer.equals("Q"))

{

ClientSocket.close();

break;

}

else

{

System.out.println("RECEIVED:"+FromServer);

System.out.println("SEND(Type Q or q to Quit):");

ToServer=inFromUser.readLine();

if(ToServer.equals("Q")||ToServer.equals("q"))

{

outToServer.println(ToServer);

ClientSocket.close();

break;

}

else

{

outToServer.println(ToServer);

}

}

}

}

}

 --------------------------------------------------------

/*PROGRAM USING UDP SOCKET*/

Source code

SERVER PROGRAM:

import java.net.*;

import java.io.*;

class UDPServer

{

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

{

byte[] receive_data=new byte[1024];

byte[] send_data=new byte[1024];

int recv_port;

DatagramSocket server_socket=new DatagramSocket(5000);

System.out.println("UDPServer waiting for client on port 5000");

while(true)

{

DatagramPacket receive_packet=new DatagramPacket(receive_data,receive_data.length);

server_socket.receive(receive_packet);

String data=new String(receive_packet.getData(),0,0,receive_packet.getLength());

InetAddress IPAddress=receive_packet.getAddress();

recv_port=receive_packet.getPort();

if(data.equals("q")||data.equals("Q"))

break;

else

System.out.println("("+IPAddress+","+recv_port+")said:"+data);

}

}

}

CLIENT PROGRAM:

import java.net.*;

import java.io.*;

class UDPClient

{

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

{

byte[] send_data=new byte[1024];

BufferedReader infromuser=new BufferedReader(new InputStreamReader(System.in));

DatagramSocket client_socket=new DatagramSocket();

InetAddress IPAddress=InetAddress.getByName("127.0.0.1");

while(true)

{

System.out.println("Type something(q or Q to quit):");

String data=infromuser.readLine();

if(data.equals("q")||data.equals("Q"))

break;

else

{

send_data=data.getBytes();

DatagramPacket send_packet=new DatagramPacket(send_

data,send_data.length,IPAddress,5000);

client_socket.send(send_packet);

}

}

client_socket.close();

}

}

/*SIMULATION OF SLIDING WINDOW PROTOCOL*/

SOURCE CODE:

//SENDER:

import java.net.*;

import java.io.*;

import java.rmi.*;

public class Sender

{

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

{

ServerSocket ser=new ServerSocket(10);

Socket s=ser.accept();

DataInputStream in=new DataInputStream(System.in);

DataInputStream in1=new DataInputStream(s.getInputStream());

String sbuff[]=new String[8];

PrintStream p;

int sptr=0,sws=8,nf,ano,i;

String ch;

do

{

p=new PrintStream(s.getOutputStream());

System.out.println("Enter the no.of frames:");

nf=Integer.parseInt(in.readLine());

p.println(nf);

if(nf<=sws-1)

{

System.out.println("Enter"+nf+"messages to be send\n");

for(i=1;i<=nf;i++)

{

sbuff[sptr]=in.readLine();

p.println(sbuff[sptr]);

sptr=++sptr%8;

}

sws-=nf;

System.out.println("Acknowledgement received");

ano=Integer.parseInt(in1.readLine());

System.out.println("for"+ano+"frames");

sws+=nf;

}

else

{

System.out.println("The no.of frames exceeds window size");

break;

}

System.out.println("Do you wants to send some more frames:");

ch=in.readLine();

p.println(ch);

}

while(ch.equals("yes"));

s.close();

}

}

//CLIENT:

import java.net.*;

import java.io.*;

class Receiver

{

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

{

Socket s=new Socket(InetAddress.getLocalHost(),10);

DataInputStream in=new DataInputStream(s.getInputStream());

PrintStream p=new PrintStream(s.getOutputStream());

int i=0,rptr=-1,nf,rws=8;

String rbuff[]=new String[8];

String ch;

System.out.println();

do

{

nf=Integer.parseInt(in.readLine());

if(nf<=rws-1)

{

for(i=1;i<=nf;i++)

{

rptr=++rptr%8;

rbuff[rptr]=in.readLine();

System.out.println("The received frame"+rptr+"is:"+rbuff[rptr]);

}

rws-=nf;

System.out.println("\nAcknowledgement sent\n");

p.println(rptr+1);

rws+=nf;

}

else

break;

ch=in.readLine();

}while(ch.equals("yes"));

}

}