/**

* Java. Level 2. Lesson 6. Networking

* Class HelloServer: waiting and sending message to the client

*

* @author Sergey Iryupin

* @version dated Jan 12, 2018

*/

import java.net.*;

import java.io.*;

class HelloServer {

public static void main(String[] args) {

new HelloServer();

}

HelloServer() {

try (ServerSocket server = new ServerSocket(1024)) {

String ipAddress = getPublicIP("http://checkip.amazonaws.com");

System.out.println("Server started on IP " + ipAddress);

while (true) {

Socket socket = server.accept();

PrintWriter writer = new PrintWriter(socket.getOutputStream());

writer.println("Server from IP " + ipAddress + " says: Hello");

System.out.println("Message sent to client.");

writer.close();

}

} catch (IOException ex) {

System.out.println(ex);

}

}

private String getPublicIP(String url) throws IOException {

URL checkURL = new URL(url);

BufferedReader reader = new BufferedReader(

new InputStreamReader(checkURL.openStream()));

return reader.readLine();

}

}