Java Socket Chat unable to establish connection to port

Question!

I am trying to code a simple server and client chat application, however my code jumps straight to the exception, meaning it cannot create the connection to the port.

Server:

public class Server
{
   public static void main(String args[])
   {
   try
   {
       ServerSocket ss = new ServerSocket(80);
       Socket sock = ss.accept();
       DataInputStream recive = new DataInputStream(sock.getInputStream());
       DataOutputStream sendOut = new DataOutputStream(sock.getOutputStream());
       BufferedReader readOut = new BufferedReader(new InputStreamReader(System.in));

       String in = "";
       String out = "";
       Scanner scan = new Scanner(System.in);
       System.out.println("Talk with client(y/n): ");
       String start = scan.nextLine();
       while(start == "y")
       {
       in = recive.readUTF();
       System.out.println(in);
       out = readOut.readLine();
       sendOut.writeUTF(out);
       sendOut.flush();
      }
    }
    catch(IOException e)
    {System.out.println("[!]CANNOT ESTABLISH CONNECTION[!]");}

  }
}


Answers

Make sure that the port that you have specified is not already in use (port number 80) . It is likely that you may be running another application on the same port (such as a web server).

You can also refer this example: Basic Client and Server Communication using a Socket

By : Hiren


The reason this is not working as you expect is you are comparing JSON text to a text value.

You should cast the JSON value to the appropriate type, which is numeric, and compare to a number.

For example:

    select address from listing where ('address.coords.latitude')::numeric < 40;
By : slayer49


You're calling your static variable/method through object instead of the class where it's defined. When it says 'by declaring type ' it means that you declared your variable/method as a class variable/method and you should call it by that.



This video can help you solving your question :)
By: admin