client –server application for chat using UDP Sockets

Aim

Write a Program client –server application for chat using UDP Sockets

Program

UDPserver.java

import java.io.*;

import java.net.*;

class UDPserver

{

public static DatagramSocket ds;

public static byte buffer[]=new byte[1024];

public static int clientport=789,serverport=790;

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

{

ds=new DatagramSocket(clientport);

System.out.println("press ctrl+c to quit the program");

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

InetAddress ia=InetAddress.geyLocalHost();

while(true)

{

DatagramPacket p=new DatagramPacket(buffer,buffer.length);

ds.receive(p);

String psx=new String(p.getData(),0,p.getLength());

System.out.println("Client:" + psx);

System.out.println("Server:");

String str=dis.readLine();

if(str.equals("end"))

break;

buffer=str.getBytes();

ds.send(new DatagramPacket(buffer,str.length(),ia,serverport));

}

}

}

UDPclient.java

import java .io.*;

import java.net.*;

class UDPclient

{

public static DatagramSocket ds;

public static int clientport=789,serverport=790;

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

{

byte buffer[]=new byte[1024];

ds=new DatagramSocket(serverport);

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

System.out.println("server waiting");

InetAddress ia=InetAddress.getLocalHost();

while(true)

{

System.out.println("Client:");

String str=dis.readLine();

if(str.equals("end"))

break;

buffer=str.getBytes();

ds.send(new DatagramPacket(buffer,str.length(),ia,clientport));

DatagramPacket p=new DatagramPacket(buffer,buffer.length);

ds.receive(p);

String psx=new String(p.getData(),0,p.getLength());

System.out.println("Server:" + psx);

}

}

}

OUTPUT:

Server

C:\Program Files\Java\jdk1.5.0\bin>javac UDPserver.java

C:\Program Files\Java\jdk1.5.0\bin>java UDPserver

press ctrl+c to quit the program

Client:Hai Server

Server:

Hello Client

Client:How are You

Server:

I am Fine

Client

C:\Program Files\Java\jdk1.5.0\bin>javac UDPclient.java

C:\Program Files\Java\jdk1.5.0\bin>java UDPclient

server waiting

Client:

Hai Server

Server:Hello Clie

Client:

How are You

Server:I am Fine

Client:

end

CLIENT SERVER APPLICATION FOR CHAT

SERVER SIDE:

#include<stdio.h>

#include<sys/types.h>

#include<sys/socket.h>

#include<netinet/in.h>

#include<string.h>

int main(int argc,char **argv)

{

int len;

int listenfd,connfd,n;

int i,j,k=0,l,count=0;

struct sockaddr_in servaddr,cliaddr;

char buff[1024];

char str[1000];

listenfd=socket(AF_INET,SOCK_STREAM,0);

if(listenfd<0)

perror("cant create socket");

bzero(&servaddr,sizeof(servaddr));

servaddr.sin_family=AF_INET;

servaddr.sin_addr.s_addr=INADDR_ANY;

servaddr.sin_port=htons(20060);

bind(listenfd,(struct sockaddr *)&servaddr,sizeof(servaddr));

listen(listenfd,5);

len=sizeof(cliaddr);

connfd=accept(listenfd,(struct sockaddr *)&cliaddr,&len);

n=read(connfd,buff,1024);

printf("\n received message is %s\t",buff);

l=strlen(buff);

for(i=0;i<l;i++)

{

if(buff[i]=='l')

{

k=i;

count=0;

while(buff[k]=='l')

{

count++;

k++;

if(count==5)

{

for(j=k;j<l-1;j++)

buff[j]=buff[j+1];

l--;

buff[l]=='\0';

break;

}

i=k;

}

}

}

printf("\n unstuffed string is %s\n",buff);

close(connfd);

return 0;

}

CLIENT SIDE:

#include<stdio.h>

#include<sys/types.h>

#include<sys/socket.h>

#include<netinet/in.h>

#include<string.h>

int main(int argc,char **argv)

{

int len;

int sockfd,n,connfd;

int l,k=0,i,j,count=0;

struct sockaddr_in servaddr,cliaddr;

char buff[1024];

char str[1000];

sockfd=socket(AF_INET,SOCK_STREAM,0);