World Wide VB

Two interesting talking points at the moment between Google's AJAX Framework and Continutations. Starting with, Continuations and GUIs, "...Web UIs are drastically constrained, offer a paucity of controls, and enforce a brutally linear control flow; and these are good things. I remember, in the early days, people saying “Once you know how to use one Windows app, you know how to use them all”. Ha ha ha. But you know what? Once you know how to use a browser, you are well on the way to being able to use most Web apps. The best AJAX apps are still very Web-like (as in, the Back button always works); but they’re faster and more responsive and nicer to look at. The worst AJAX apps are like bad Nineties VB."

This linked to: Continuations, cont’d "...there’s no need to drive a continuation bulldozer through your webapp, when a little REST garden spade will work quite nicely (and won’t tear up your lawn in the process). Don suggests that there may be other, more legitimate use cases for continuations outside of web applications, and I have no reason to disagree, but I would like to look at them pretty carefully."

The seed of the continued continuations conversation was, "Will Continuations continue?".

The Google Web Toolkit gets a reasonable overview, "GWT: Googles plain Java AJAX tools". This seems to be a similar approach taken by DWR 2.0 (out since late April) - using Java to write Javascript. DWR 2.0 also supports Jetty's AJAX continuations.

Update: So GWT is not like DWR. With DWR you still create your HTML and Javascript pages directly. With GWT you use widgets and lay them out like Swing - there's no direct access to the Javascript or layout. There is some criticism that this approach is at the wrong level of abstraction. One of the potential advantages is the ability to test drive the Java code and then deploy the Javascript - and hope that there are no bugs in only the Javascript version.