DWR 2.0

by Dejan Bosanac

I just saw the release note for DWR 2.0 milestone 1. It introduces many new features, but the most interesting is certainly "Reverse Ajax", which allows Java code to asynchronously call JavaScript code in the browser.

I've used DWR on few projects in the past and I find it to be a very good AJAX implementation for Java. Also, I can think of some very good use-cases for these new features, so I will certainly put my hands on this new release soon. How about you? What is your experience with DWR and what do you think of these new capabilities?


Nic Ferrier
2006-04-12 01:30:42
I don't know anything about DWR but if Java can call back into the UA there must be a fixed link established from the UA to the backend and that would be a horribly bad idea.
Joe Walker
2006-04-12 04:09:17
DWR 2.0 allows you to use either natural connections (slow, but no extra bandwidth), or polling (fairly fast, but can be high bandwidth depending on the poll speed) or comet - what I think you mean by fixed link (very fast, OK for small servers - for larger servers you need a continuations mechanism like in Jetty6)


Dejan Bosanac
2006-04-12 06:21:30
Indeed, Jetty continuations and DWR together can make a powerful AJAX environment.
Glen Smith
2006-04-12 19:21:15
+1. DWR is just awesome. Rock solid library with great documentation. Kudos to Joe and the guys for a great piece of work. I gave a demo to our local JUG last night on a Sudoku Solver using DWR (Demo) which was developed by exposing a Spring bean over DWR. Makes the web tier so simple.

The reverse Ajax stuff is going to be perfect for a Monitoring app we're developing (think: broadcasting of monitoring results to all clients presently online). Can't wait to take it for a spin.
2006-09-11 06:45:07
2008-01-20 21:23:03
I am satisfied with DWR2.0 but I think more documentation is needed. Recently I migrated my project from DWR1.2 to DWR2.0 but I faced some difficulty. like { escapeHtml:false },we can set { escapeHtml:false } parameter with dwr.util.setValue() function but not with dwr.util.setValues().Another problem is about setting checkbox value. At DWR1.2 we can check and uncheck by any valid value but in DWR2.0 it is not possible except true or false.