import java.io.*;

import java.net.*;

import java.util.*;

public class ServerAB {

public static void main(String[] args) {

new ServerAB();

}

public ServerAB() { // constructor

try {

// Create a server socket

ServerSocket serverSocket = new ServerSocket(8000);

System.out.println("Server started at " + new Date() + '\n');

// Listen for a connection request

Socket socket = serverSocket.accept();

// Create data input and output streams

DataInputStream inputFromClient = new DataInputStream(

socket.getInputStream());

DataOutputStream outputToClient = new DataOutputStream(

socket.getOutputStream());

while (true) {

// Receive radius from the client

double radius = inputFromClient.readDouble();

InetAddress ip = socket.getInetAddress();

System.out.println("Host Name: " + ip.getHostName());

System.out.println("IP Address: " + ip.getHostAddress());

System.out.println("We have received radius value "+ radius);

// Compute area

double area = radius * radius * Math.PI;

// Send area back to the client

outputToClient.writeDouble(area);

}

} catch(IOException ex) {

System.err.println(ex);

}

}

}