Extended WebSocketServer

import org.java_websocket.WebSocket;
import org.java_websocket.handshake.ClientHandshake;
import org.java_websocket.server.WebSocketServer;

import java.net.InetSocketAddress;
import java.net.UnknownHostException;
import java.util.Collection;

public class CustomWebSocketServer extends WebSocketServer {

    private static int Port = 80;
    private static CustomWebSocketServer ourInstance = null;

    public static CustomWebSocketServer getInstance() {
        if (ourInstance == null) {
            try {
                ourInstance = new CustomWebSocketServer(Port);
            } catch (Exception e) {
                Main.logger.warning("Cannot create instance of WebSocketServer on port " + Port);
            }
        }
        return ourInstance;
    }

    public CustomWebSocketServer(int port) throws UnknownHostException
    {
        super(new InetSocketAddress(port));
    }

    @Override
    public void onOpen(WebSocket conn, ClientHandshake handshake)
    {
        Main.logger.info("WebSocketServer::onOpen()");
    }

    @Override
    public void onClose(WebSocket conn, int code, String reason, boolean remote)
    {
        Main.logger.info("WebSocketServer::onClose() - " + code + " / " + reason);
    }

    @Override
    public void onMessage(WebSocket conn, String message)
    {
        Main.logger.info("WebSocketServer::onMessage() - " + message);
        sendToAll("Tnx for message");
    }

    @Override
    public void onError(WebSocket conn, Exception ex)
    {
        Main.logger.warning("WebSocketServer::onError() - " + ex.getMessage());

        if (conn == null) {
            // TAG: ---HERE---
            Main.logger.warning("WebSocketServer::onError() - exit(1)");
            System.exit(1);
        }
    }

    public void sendToAll(String text)
    {
        Collection<WebSocket> con = connections();
        synchronized(con) {
            for (WebSocket c : con) {
                c.send(text);
            }
        }
    }

}