Monday, December 4th, 2006
Application Development with Echo2 plus SOA
Mathew Brooks of RDF Group has published a summary of his experiences in developing mform — an Ajax-enabled mortgage application — using the Echo2 platform. Although fairly high level, the post is thought provoking and doesn’t just focus just on Ajax. With regard to best practices in using Echo2, he writes:
Whilst using echo 2 we discovered that whilst it was the most advanced tool for the job (at least when we started, which was before GWTcame out) we did find that we had to undertake the following:
- Adjust some of the java script in widget peers where it was not quite performing as we expected
- Subclass the echo 2 servlet to ensure that:
- We can trap non java script type clients and present a “non javascript” type version of the page
- We can present a more polished start up page rather than the ||| presented as default by echo 2
- Some post back functionality does not work well with IE either under load or restricted bandwidth. Due to the way that IE polls for the post back other events on the browser were being missed.
- Develop our own widgets where necessary if there was no suitable one available from echo or echopointNG
Beyond Echo2, the application makes use of ServiceMix (the Open Source ESB), Spring, Hibernate and EJB3. It also integrates with a CMS — Hippo — for conetent management. I haven’t used ServiceMix myself, but I have used the Mule ESB myself (it has much better docs and tutorials, IMHO), and beyond the SOA help it provides, I’ve found it’s support for FutureTask very helpful for some of the asynchronous processing you see more of in Ajax apps.
Mathew’s analysis goes well beyond just Ajax, of course, with some thoughts on how to avoid the Anaemic Data Model antipattern, among other things.
Echo2 looks like it uses polling to implement its “Ajax Push”.
Yes, Echo2 does use polling, though so do most examples of “push,” with the exception of Comet.
It’s great to see these tools available to developers, but it just irritates me that someone is making a profit off of open source development like this. Eclipse is open source, and JavaScript is too. So why are they charging people to use the Echo2 plugin. I’ve been using AWT with Eclipse, and I highly recommend it for those developing in the AJAX realm. There are alternatives out there. Don’t buy into the hype.
I’m not sure that’s a fair assessment. Echo2 is Open Source developed by NextApp. You can develop Echo2 apps without the eclipse plugin. If NextApp wants to provide a commercial Eclipse plugin to make it easier to develop apps in Echo2, more power to them.
Just to let you know that I will be at Javapolis in Antwerp 11-15th of this month. If anyone wants to meet up to discuss this project and technical architecture in general drop me a line at mbrooks@rdfgroup.com
Matthew Brooks
Wow, I can’t believe I’ve never heard of echo…
I saw the demonstration of Echo2 and it’s quite nice.
Besides Echo2 and GWT mentioned in the article, you should also look into IT Mill Toolkit when looking for “Code in Java, Ajax is also there” -framework:
demo, manual, download, features, more info
Ajax is the only way to go IMHO.
We have successfully implemented echo2 as our GUI layer for a large project and have not looked back since. The echo2 API is atable and the HTML rendered output is truly browser independent!
An echo user session does require a bit of memory overhead, but the benefits far outweight the costs.
We used echo2 for one of our clients (large mortgage firm) about 6 months ago and they are very satisfied with the functionality so far.