java program to establish connection between server and client.

--------------------------------for Client-----------------------

import java.io.*;
import java.net.*;
public class Client {
public static void main(String[] args )
{
String hostname="127.0.0.1";
int portNumber=9991;
try
{


Socket echoSocket=new Socket(hostname,portNumber);
PrintWriter out=new PrintWriter(echoSocket.getOutputStream(),true);
BufferedReader in=new BufferedReader(new InputStreamReader(echoSocket.getInputStream()));

BufferedReader stdIn=new BufferedReader(new InputStreamReader(System.in));
String userInput;
while ((userInput=stdIn.readLine()) !=null)
{
out.println(userInput);
System.out.println("ëcho: " + in.readLine());
}
echoSocket.close();
}catch(Exception e)
{
System.out.println("exception occured  :" + e);
}

}
}

-------------------------------------for Server------------------------------


import java.io.*;
import java.net.*;
public class Server {
public static void main(String[] args) throws Exception
{

int portNumber=9991;

ServerSocket echoServerSocket=new ServerSocket(portNumber);
Socket s1=echoServerSocket.accept();
PrintWriter out=new PrintWriter(s1.getOutputStream(),true);
BufferedReader in=new BufferedReader(new InputStreamReader(s1.getInputStream()));

BufferedReader stdIn=new BufferedReader(new InputStreamReader(System.in));
String userInput;
while ((userInput=in.readLine()) !=null)
{
out.println(userInput);
System.out.println("ëcho: " + in.readLine());
}
echoServerSocket.close();
}
}

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