Java socket run on localhost against outside server

Question

Hi everyone,
I am newbie to Java socket and networking. By spending this weekend over the internet reading and researching I have made my first Server-Client java socket program run sucessfully on my localhost 127.0.0.1. They can be connected and ok to communicate.
However, when I put my server program to the LIVE server outside the network the client side says cannot connect to the server because: Connection Error, Connection refused: connect. So I read some stuff about firewall and NAT on the web but i was shamed that I don't understand there is any solution to this.
It is great appreciated if someone can point me out how can I resolve this or make a step out because I am running out of time to give out the program against the deadline. But I really thank you anyone has been reading this.
The server code:
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package instantmessenger;
import java.io.*;
import java.net.*;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
    public class Server extends JFrame implements ActionListener {
        JTextArea textreceive   =new JTextArea();
        JTextArea textsend      =new JTextArea();
        JButton button          =new JButton("Send");
        BufferedReader in;
        PrintWriter out;
        public Server () {
                //init   controls
                setTitle("Server");
                setBounds(50,50,500,400);
                getContentPane().setLayout(null);
                getContentPane().add(textreceive);
                getContentPane().add(textsend);
                getContentPane().add(button);
                textreceive.setBounds(10,10,450,300);
                textsend.setBounds(10,320,350,30);
                button.setBounds(370,320,70,30);
                button.addActionListener(this);
        public void listenClient() throws IOException {
                ServerSocket   server=new   ServerSocket(9999);
                System.out.println("start:"+server);
                textreceive.append("start"+server+"\n");
                try {
                        Socket s = server.accept();
                        try {
                                System.out.println("connecting   :"+s);
                                textreceive.append("connecting   :"+s+"\n");
                                in = new BufferedReader(new InputStreamReader(s.getInputStream()));
                                    out=new   PrintWriter(
                                    new   BufferedWriter(
                                    new   OutputStreamWriter(s.getOutputStream())));
                                out = new PrintWriter(s.getOutputStream());
                                String str=null;
                                while(true) {
                                        str = in.readLine();
                                        System.out.println(str);
                                        textreceive.append(str+"\n");
                        finally {
                            s.close();
                finally {
                    server.close();
        } // end function
        public void actionPerformed(ActionEvent event) {
                String str = textsend.getText();
                if( !str.equals("")) {
                        out.println(textsend.getText());
                        //out.println(textsend.getText());
                        out.flush();
                        textreceive.append(textsend.getText()+"\n");
                        textsend.setText("");
        } // end function
        public   static   void   main(String   args[])   throws   IOException {
            Server   s=new   Server();
            s.show();
            s.listenClient();
        } // end function
    } // end classThe client source code:
package instantmessenger;
    import   java.net.*;
    import   java.io.*;
    import   javax.swing.*;
    import   java.awt.*;
    import   java.awt.event.*;
    public   class   Client   extends   JFrame implements   ActionListener {
        JTextArea   textreceive=new   JTextArea();
        JTextArea   textsend   =new   JTextArea();
        JButton     button   =new   JButton   ("Send");
        BufferedReader  in;
        PrintWriter     out;
        public Client(){
                //init   controls
                setTitle("Client");
                setBounds(50,50,500,400);
                getContentPane().setLayout(null);
                getContentPane().add(textreceive);
                getContentPane().add(textsend);
                getContentPane().add(button);
                button.addActionListener(this);
                textreceive.setBounds(10,10,450,300);
                textsend.setBounds(10,320,350,30);
                button.setBounds(370,320,70,30);
       } // init
        public void startNet() throws IOException {
              //Socket client=new Socket("localhost",9999);
              Socket client=new Socket("222.33.444.5555",9999);  // NOT REAL SERVER IP
              try {
                      System.out.println("Socket="   +client);
                      in    =   new BufferedReader(new InputStreamReader(client.getInputStream()));
                      out   =   new PrintWriter(new BufferedWriter(new OutputStreamWriter(client.getOutputStream())),true);
                      String str=null;
                      while(true) {
                          str   =   in.readLine();
                          System.out.println(str);
                          textreceive.append(str+"\n");
              finally {
                    client.close();
        } // end function
        public void actionPerformed(ActionEvent   event) {
            String str=textsend.getText();
            if(!str.equals("")) {
                out.println(textsend.getText());
                //out.println(textsend.getText());
                out.flush();
                textreceive.append(textsend.getText()+"\n");
                textsend.setText("");
        } // function
        public static void main(String args[]) throws IOException {
            Client c=new Client();
            c.show();
            c.startNet();
        } // function
} // end classThank you
Morris Lee

Answer 1

However, when I put my server program to the LIVE server outside the network the client side says cannot connect to the server because: Connection Error, Connection refused: connect. So I read some stuff about firewall and NAT on the web but i was shamed that I don't understand there is any solution to this.What do you want us to do? You already know that the problem probably is that you need to open port 9999 in the firewall, and you probably also need to configure it for port forwarding.
Most clients will be able to connect after that, but some might still have problems. E.g. some companies don't allow clients to connect to other ports than a few well known ones (e.g. 21, 80 and 443)