Problem with sockets example

[Vladimir Vucetic]

I am trying to run example from "Head First Book Java" sockets chapter, but have no luck.
This should be server code project:

public class Main {

	String[] adviceList = {"Take smaller bites", "Go for the tight jeans. No they do NOT make you look fat",
	        "One word: inappropriate", "Just for today, be honest.  Tell your boss what you *really* think", 
	        "You might want to rethink that haircut"};
	        
	    public void go() {
	        try {
	            ServerSocket serverSock = new ServerSocket(4242);
	            while (true)
	            {
	                Socket sock = serverSock.accept();
	                
	                PrintWriter writer = new PrintWriter(sock.getOutputStream());
	                String advice = getAdvice();
	                writer.println(advice);
	                writer.close();
	                System.out.println(advice);
	            }
	        } catch (IOException ex)
	        {
	            ex.printStackTrace();
	        }
	    }
	    
	    private String getAdvice() {
	        int random = (int) (Math.random() * adviceList.length);
	        return adviceList[random];
	    }
	    
	    public static void main(String[] args)
	    {
	    	Main server = new Main();
	        server.go();
	    }

}

This shoud be client code project.

public class Main {

	public void go() {
        try {
            Socket s = new Socket("127.0.0.1", 4242);
            InputStreamReader streamReader = new InputStreamReader(s.getInputStream()); 
            BufferedReader reader = new BufferedReader(streamReader);
            
            String advice = reader.readLine();
            System.out.println("Today you should: " + advice);
            reader.close();
        }
        catch (IOException ex)
        {
            ex.printStackTrace();
        }
    }
    
    public static void main(String[] args)
    {
    	Main client = new Main();
        client.go();
    }

}

I first run server project and then run client but have no luck.
When I run server project error text is:

java.net.SocketException: Unrecognized Windows Sockets error: 0: JVM_Bind
	at java.net.PlainSocketImpl.socketBind(Native Method)
	at java.net.PlainSocketImpl.bind(PlainSocketImpl.java:365)
	at java.net.ServerSocket.bind(ServerSocket.java:319)
	at java.net.ServerSocket.<init>(ServerSocket.java:185)
	at java.net.ServerSocket.<init>(ServerSocket.java:97)
	at Main.go(Main.java:14)
	at Main.main(Main.java:39)

What is the problem here?

[Vladimir Vucetic]

I am sorry it from some unknown reason start working. But I am not sure why that error occurred before

[David Newton]

This error is sometimes related to trying to open a port that's already open; it may just be that you already had an instance running.

Glad you got it working, though!