Need a lot of help with networking

Question

How would you make a program that would send a message to another person? Im fairly new a networking in java, and i cant seem to get the tutorials to work. Can anyone out there help me?

Answer 1

import java.io.PrintWriter;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
public class TCPEchoServer
   private static ServerSocket servSock;
   private static final int PORT = 1234;
   public static void main(String[] args)
      System.out.println("Opening port...\n");
      try
         servSock = new ServerSocket(PORT);      //Step 1.
      catch(IOException e)
         System.out.println("Unable to attach to port!");
         System.exit(1);
      do
         run();
      }while (true);
   private static void run()
      Socket link = null;                        //Step 2.
      try
         link = servSock.accept();               //Step 2.
         BufferedReader in =
              new BufferedReader(
                    new InputStreamReader(
                        link.getInputStream())); //Step 3.
         PrintWriter out = new PrintWriter(
                   link.getOutputStream(),true); //Step 3.
         int numMessages = 0;
         String message = in.readLine();         //Step 4.
         while (!message.equals("***CLOSE***"))
            System.out.println("Message received." +message);
            numMessages++;
            out.println("Message " + numMessages
                          + ": " + message);     //Step 4.
            message = in.readLine();
         out.println(numMessages
                         + " messages received.");     //Step 4.
          catch(IOException e)
               e.printStackTrace();
          finally
               try
                    System.out.println(
                                        "\n* Closing connection... *");
                    link.close();                        //Step 5.
               catch(IOException e)
                    System.out.println("Unable to disconnect!");
                    System.exit(1);
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.IOException;
import java.io.PrintWriter;
import java.net.UnknownHostException;
import java.net.Socket;
import java.net.InetAddress;
public class TCPEchoClient
     private static InetAddress host;
     private static final int PORT = 1234;
     public static void main(String[] args)
          try
               //host = InetAddress.getByName("A1005-22");
               host = InetAddress.getLocalHost();
          catch(UnknownHostException e)
               System.out.println("Host ID not found!");
               System.exit(1);
          run();
     private static void run()
          Socket link = null;                    //Step 1.
          try
               link = new Socket(host,PORT);          //Step 1.
               BufferedReader in =
                    new BufferedReader
                         (new InputStreamReader
                                 (link.getInputStream()));//Step 2.
               PrintWriter out = new PrintWriter(
                         link.getOutputStream(),true);      //Step 2.
               //Set up stream for keyboard entry...
               BufferedReader userEntry =
                         new BufferedReader
                               (new InputStreamReader(System.in));
               String message, response;
               do
                    System.out.print("Enter message: ");
                    message =  userEntry.readLine();
                    out.println(message);           //Step 3.
                    response = in.readLine();          //Step 3.
                    System.out.println("\nSERVER> " + response);
               }while (!message.equals("***CLOSE***"));
          catch(IOException e)
               e.printStackTrace();
          finally
               try
                    System.out.println(
                                   "\n* Closing connection... *");
                    link.close();                    //Step 4.
               catch(IOException e)
                    System.out.println("Unable to disconnect!");
                    System.exit(1);
}