I was looking for something about js so I decided to make a simple scan port with dialogs.
If you got any question please ask.
I also got the .jar so if someone wants it let me know.

Code:
import java.net.*;  
import java.io.IOException;  
import javax.swing.*;  
import java.awt.*;  
import java.awt.event.*;  
    public class Main {  
         public static void main(String[] args) {  
         InetAddress ia=null;  
         String host=null; 
         String getPort = null;
        String showDialog = null;
         
         Object[] result_show = {"Console","Dialog"};
         
         int port = 0;
             try {  
              
             host=JOptionPane.showInputDialog("Enter the Host name to scan:\n example: xxx.ro"); 
             getPort=JOptionPane.showInputDialog("Port?");
             showDialog =  (String)JOptionPane.showInputDialog(null,"Were do you want to see the result?","Question",JOptionPane.PLAIN_MESSAGE,null,result_show,"Console");
             port = Integer.parseInt(getPort);    
                 if(host!=null){  
                 ia = InetAddress.getByName(host);  
             scan(ia,port,showDialog); }  
         }  
             catch (UnknownHostException e) {  
             System.err.println(e );  
         }  
         System.exit(0);  
     }  
         
         public static void scan(final InetAddress remote,int port,String showDialog){
        	 String hostname = remote.getHostName();
        	 try{
        		 Socket s = new Socket(remote,port);
        		 if((showDialog != null) && (showDialog.length() > 0 ) && (showDialog == "Dialog")){
                 	JOptionPane.showMessageDialog(null, "Port (open): " + port + " on host " + hostname);
                 }else{
        		 System.out.println("Port (open): " + port + " on host "+ hostname); }
        		 s.close();
        		 
        	 }
        	 catch(IOException ex){
        		 if((showDialog != null) && (showDialog.length() > 0 ) && (showDialog == "Dialog")){
                  	JOptionPane.showMessageDialog(null, "Port (close): " + port + " on host " + hostname);
                  }else{
        		 System.out.println("Port (close): " + port + " on host " + hostname); }
        		 
        	 }
        	 
         }