import java.io.*;

import java.net.*;

import java.util.Date;

import javafx.application.Application;

import javafx.application.Platform;

import javafx.scene.Scene;

import javafx.scene.control.ScrollPane;

import javafx.scene.control.TextArea;

import javafx.stage.Stage;

public class Server extends Application {

@Override

public void start(Stage primaryStage) {

TextArea ta = new TextArea();

Scene scene = new Scene(new ScrollPane(ta), 450, 200);

primaryStage.setTitle("Server");

primaryStage.setScene(scene);

primaryStage.show();

new Thread(() -> {

try {

ServerSocket serverSocket = new ServerSocket(8000);

Platform.runLater(() ->

ta.appendText("Server started at " + new Date() + '\n'));

Socket socket = serverSocket.accept();

DataInputStream inputFromClient = new DataInputStream(socket.getInputStream());

DataOutputStream outputToClient = new DataOutputStream(socket.getOutputStream());

while (true) {

double radius = inputFromClient.readDouble();

double area = radius * radius * Math.PI;

outputToClient.writeDouble(area);

Platform.runLater(() -> {

ta.appendText("Radius received from client: " + radius + '\n');

ta.appendText("Area is: " + area + '\n');

});

}

}

catch(IOException ex) {

ex.printStackTrace();

}

}).start();

}

}