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

public class EchoClient {
  public static void main(String[] args) throws IOException {
    
    if (args.length != 2) {
      System.err.println(
        "Usage: java EchoClient <host name> <port number>");
      System.exit(1);
    }

    String hostName = args[0];
    int portNumber = Integer.parseInt(args[1]);
    InetSocketAddress socketAddress = new InetSocketAddress(hostName, portNumber);

    try (
      Socket echoSocket = new Socket();      
      BufferedReader stdIn =
        new BufferedReader(
          new InputStreamReader(System.in));
    ) {
      echoSocket.connect(socketAddress);
      System.out.println("Connected to "+echoSocket.getInetAddress().toString()+":"+echoSocket.getPort());
      try (
        PrintWriter out = new PrintWriter(echoSocket.getOutputStream(), true);
        BufferedReader in = new BufferedReader( new InputStreamReader(echoSocket.getInputStream() ));
      ) {
        String userInput;
        while ((userInput = stdIn.readLine()) != null) {
          out.println(userInput);
          System.out.println("echoed: "+in.readLine());
        }
      }
      // no catch
    } catch (UnknownHostException e) {
      System.err.println("Don't know about host " + hostName);
      System.exit(1);
    } catch (IOException e) {
      System.err.println("Couldn't get I/O for the connection to " +
        hostName);
      System.exit(1);
    }
  }
}