Socket program erroring out

Hi,
I have the following basic socket program :

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.Date;

public class JokeServer {
    static final char[] EOL = {(char) '\r', (char) '\n'};

    public static void main(String a[]) throws IOException {
        // Using try with resources as it closes everything autocloseable
        try (
                ServerSocket serverSocket = new ServerSocket(Constants.jokeServerPort, Constants.backLog);
                Socket socket = serverSocket.accept();
                BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
                PrintWriter out = new PrintWriter(socket.getOutputStream(), true);
        ) {
            out.println("HTTP/1.1 200 OK");
            out.println("Content-type: " + "application/json");
            out.println("Content-Length: " + 10);
            out.write("\r\n");
        }
    }

}

The port here is 4545.
Now when i use http://localhost:4545/  from chrome after running the above server.
The server stops. And in chrome network tab all i see is red color request nothing else
How to find out what error exactly it is.

Also i tried doing  curl -i -H "Accept: application/json" http://localhost:4545 
The ouput was  -
curl: (7) Failed to connect to localhost port 4545: Connection refused
Dont know what that means.

what could be the reason for these errors and how to resolve them.

Thanks