import java.io.*;
import java.net.*;

public class ServerTest2 {

public static void main(String[] argv) {

  try {
      ServerSocket serverSocket = new ServerSocket(2000); // Create Socket and bind to port 2000
      System.out.println("Created");
      Socket clientSocket = serverSocket.accept(); //Wait for client and if possible accept
      System.out.println("Connection accepted");
      BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(clientSocket.getOutputStream())); // for outputs
      BufferedReader br = new BufferedReader(new InputStreamReader(clientSocket.getInputStream())); // for inputs

      String request; // requst/input of client
      String answer; // the answer for the client

      System.out.println("Start Waiting");
      request = br.readLine(); //Wait for input from client
      answer = "answer to "+request;
      bw.write(answer);  // Send answer to client
      System.out.println("send");
      bw.newLine();
      bw.flush();

      //Shut everything down
      bw.close();
      br.close();
      clientSocket.close();
      serverSocket.close();
    }
    catch (Exception e) {
      System.out.println(e);
    }
  }
}

import java.io.*;
import java.net.*;

public class ClientTest2 {

public static void main(String[] argv) {

  try {
      String host = "185.75.149.8"; //public ip of router
      Socket clientSocket = new Socket(host,2000);  //Create and connect Socket to the host on port 2000

      BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(clientSocket.getOutputStream())); // for outputs
      BufferedReader br = new BufferedReader(new InputStreamReader(clientSocket.getInputStream())); // for inputs

      String answer;
      String request = "HelloWorld";

      bw.write(request); //Write to server
      bw.newLine();
      bw.flush();
      System.out.println("Waiting");
      answer = br.readLine(); //Wait for answer

      System.out.println("Host = "+host);
      System.out.println("Echo = "+answer);

      //Shut eveything down
      bw.close();
      br.close();
      clientSocket.close();
    }
    catch (Exception e) {
      System.out.println(e);
    }
  }
}