JDK8 is going to be great. Webbit is also really nice (based on Netty).

App.java

package webserver;

import org.webbitserver.WebServers;

public class App {
  public static void main(String[] args) {
    WebServers.createWebServer(8080).add((req, res, con) -> {
      res.content("Hello, world!").end();
    }).start();
  }
}

Very slick. Will you be able to do optional function parameters in JDK8?

If you mean default parameters, no. Still have to rely on overloading. It is on my list to get in along with local type inference for variables.