Echo2 is comparable to Wt in the sense that it is a server-side library (although they call it a framework) to build web applications. On the other hand, GWT is comparable to Wt in the sense that it allows creating client-side event handling in the Java language. Wt provides this functionality using stateless slot learning, but then naturally starting from C++ code.
Combining Echo2 and GWT thus is a compelling idea, since they are two java-based complementary toolkits for web development.
Interestingly, the choice for a widget to create (which is in the framework world a component), fell on an edit-in-place field. Competitive as we are, and of course determined to show off the nice stuff in Wt, it will be nice to compare their implementation(s) to a Wt-based implementation.
Before comparing different implementations, we need to consider whether we have a comparable feature set, with respect to:
- Is the server state synchronized with client (does a 'reload' give the same page ?)
- Code size and elegance
- API -- how easy it is to use the widget/component ?
- Does client-side or server-side event handling look similar ? Can we easily switch ?
- Bandwidth usage and number of round trips
But as this is a blog, you are welcome to add additional test criteria you might be interested in !
Good luck to the Java camp!