- display dashboard pseudo realtime charts and tables
- display graphs of objects and their associations and links
- make it feel like a state of the art application with some coolness factor
- make it usable and intuitive
- make it scale
So I built some sample screens using Java Swing, the Google Web Toolkit and Adobe's Flash. I was able to somewhat build the same screen using each of these technologies. Long story short.....Java Swing was eliminated since we wanted to run in a web browser with no installation required. Adobe Flash was eliminated since it would not run on various Apple devices and required a lot of specialization. This left the Google Web Toolkit. I had never used it, but had just come off learning Oracle's ADF Technology which actually has a lot in common. Also, the development environment would be Java with Google doing the javascript generation for me. Being a Java Swing expert put me right in the driver's seat.
- Advice to any Java Swing experts out there.....learn GWT. It's a very easy transition. -
To get a jump, I bought the Essential GWT book and started reading and experimenting. I also started reading and experimenting with the copious online documentation about GWT. Turns out that the stackoverflow web site would prove extremely valuable for answering detailed technical questions.
My first task was to architect the directory structure and modeling for the application. Using a MVP (Model, View, Presenter) model was the way to go. This would allow me to later change the view code to use any widgets (maybe Droid stuff?) without changing the model or presenter code. I may never do this with my application, but at least it's architected to get there someday. In a nutshell, the View classes do the widget creation and layout. The Presenter code handles all callbacks and handlers to push data to the widgets. The Model code gets data from my db into data structures that I can access asynchronously using rpc AsyncCallback mechanisms.
Everything seemed to fall into place as the application was built. A spot for images, dialogs, events, tables, panels and third party javascript integration was created. At this point, any new feature is more of a cut and paste of an existing feature, which is exactly where a product starts to mature.
I am very impressed with the GWT performance as well. Drawing tables and charts and lists is very quick and efficient. Integration with some javascript tools has been quite easy and reliable with the JSNI implementation. CSS overriding of the GWT widgets has allowed me to completely brand the application to our company style and give it a sophisticated look and feel. No gwt-ext or ext-gwt here.
Here's to releasing the product and showing some screen shots here soon....
