Question : Java Scanner NullPointerException

I am trying to add a scanner to my application to my server so the people can type in commands and such.,, it compiles fine but when I run it I get this:

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Starting game server...
Port number: 4444

**********************
*** SERVER STARTED ***
**********************

Enter a command: Exception in thread "main" java.lang.NullPointerException
        at Server.main(Server.java:42)
Press any key to continue . . .

code:

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import java.io.*;
import java.net.*;
import java.util.*;
import java.util.Scanner;

public class Server{

    static  Socket clientSocket = null;
    static  ServerSocket serverSocket = null;
    static String responseLine;
   	public static boolean stillServ = false;
   	public static Scanner scanner;

	static  clientThread t[] = new clientThread[10];


    public static void main(String args[]) {

	// The default port



	int port_number=4444;

	if (args.length < 1)
	    {
		System.out.println("Starting game server...\nPort number: "+port_number);
		Scanner scanner = new Scanner(System.in);
	    } else {
		port_number=Integer.valueOf(args[0]).intValue();
	    }

        try {
	    serverSocket = new ServerSocket(port_number);
	    System.out.println("\n**********************\n*** SERVER STARTED ***\n**********************\n");
        }
        catch (IOException e)
	    {System.out.println(e);}


			   	System.out.print("Enter a command: ");
			   	String password = scanner.nextLine();

			   	if (password.equalsIgnoreCase("secret")) {
			   	    System.out.println("Welcome to Java Application");
			   	}


	while(true){




	    try {
		clientSocket = serverSocket.accept();
		System.out.println("*** SOMEONE CONNECTED ***\n");
		for(int i=0; i<=9; i++){
		    if(t[i]==null)
			{
			    (t[i] = new clientThread(clientSocket,t)).start();
			    break;
			}
		}
	    }
	    catch (IOException e) {
		System.out.println(e);}
	}
    }
}

class clientThread extends Thread{

	BufferedReader is = null;
    PrintStream os = null;
    Socket clientSocket = null;
    clientThread t[];
    Random roll = new Random();

    public clientThread(Socket clientSocket, clientThread[] t){
	this.clientSocket=clientSocket;
        this.t=t;
    }

    public void run()
    {

	String line;
        String name;

        int py;
	try{

	    is = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));

	    os = new PrintStream(clientSocket.getOutputStream());

	    int px = roll.nextInt(200);
	    //os.println("Enter your name.");

	    name = "Guest #" + roll.nextInt(6);

	    System.out.println(name+" has entered the game. Their attack: " + px);

	    for(int i=0; i<=9; i++)
		if (t[i]!=null && t[i]!=this)
		    t[i].os.println("*** A new user "+name+" entered the chat room !!! ***" );

	    while (true) {

		line = is.readLine();
                if(line.startsWith("/quit")) break;
		for(int i=0; i<=9; i++)
		    if (t[i]!=null)  t[i].os.println("<"+name+":"+px+"> "+line); // someone said something
	    }
	    for(int i=0; i<=9; i++)
		if (t[i]!=null && t[i]!=this) {
		System.out.println("\n" + name + " has left!\n");
		    t[i].os.println("*** The user "+name+" is leaving the chat room !!! ***" );
		}

	    os.println("*** Bye "+name+" ***");

	    for(int i=0; i<=9; i++) {
		if (t[i]==this) t[i]=null;
		System.out.println("\nSomeone has left!\n");
	}

	    is.close();
	    os.close();
	    clientSocket.close();

	}
	catch(IOException e){};



    }
}

I don't get why I am getting the error... ti worked by itself... :\

Answer : Java Scanner NullPointerException

You should be able to add the application, but need to select the executable manually. For udp/1434 it is the browser sqlbrowser.exe (usually "c:\Program Files\Microsoft SQL Server\90\Shared\sqlbrowser.exe"), for tcp/1433 sqlservr.exe ("c:\Program Files\Microsoft SQL Server\MSSQL10.EXPRESS10\MSSQL\Binn\sqlservr.exe"). You can lookup both in services.msc.

With "remote port" I meant the port of the client in the firewall. You have set it to 1433 ("Here are the settings for the firewall exception rule: protocol type is tcp, local port is 1433, remote port is 1433, ").