import com.sun.net.httpserver.HttpServer;
import java.net.InetSocketAddress;

public class Main {
    public static void main(String[] args) throws Exception {
        HttpServer server = HttpServer.create(new InetSocketAddress(8091), 0);
        server.createContext("/", exchange -> {
            byte[] body = "Hello, World! (from Java on OpenPanel)".getBytes();
            exchange.sendResponseHeaders(200, body.length);
            exchange.getResponseBody().write(body);
            exchange.close();
        });
        server.setExecutor(null);
        server.start();
        System.out.println("Listening on :8091");
    }