如何在JAVA中使用DirectionService（）GWT

Question

Is there an example anywhere that deals with DirectionService() and is up-to-date? and also in Java not javascript?
I can't find it anywhere. I want some concrete examples of how to use this.

Anyways Here are my questions:

Set the renderer to use the result from the DirectionsService. Setting a valid set of directions in this manner will display the directions on the renderer's designated map and panel.

This is what it says on the Google Map DirectionRenderer().setDirection().
And when I click to see DirectionServices, the only method is.

route(request:DirectionsRequest, callback:function(DirectionsResult, DirectionsStatus))

Which makes sense. but I have no idea how to use the callback. I've done some research but still errrors.. here are my codes.

DirectionsRequest req = DirectionsRequest.create();
req.setOrigin(userPosition);
req.setDestination(destination);
DirectionsService serv = DirectionsService.create();
serv.route(req, new ???????)

So, this is where I got stuck. The only help that I have ever found was https://github.com/branflake2267/GWT-Maps-V3-Api/blob/master/gwt-maps-showcase/src/main/java/com/google/gwt/maps/testing/client/maps/DirectionsServiceMapWidget.java
this link above. but they seem to use old version of gwt and my version doesn't work anymore. Please, any help is thankful!

Answer 1

figured out....

serv.route(req, new DirectionsService.Callback() {

        @Override
        public void handle(DirectionsResult a, DirectionsStatus b) {
            // TODO Auto-generated method stub

        }
    });

I sincerely hope someone would find this when they have this same problem