Raible Designs

Denver JUG Meeting and Struts

I managed to attend the DJUG meeting tonight (as I wrote this, time slid past midnight - oh well, it looks better on a new day). I arrived early for the Basic Concepts meeting and stayed for the Main Event. Both sessions were focused on Struts - the first being a very basic overview of MVC and Struts, and the second highlighted the newest features (i.e. Declarative Exception Handling, Validator, DynaActionForms). Like I said earlier, I wanted to meet Sue in person, so that's why I got there early. I introduced myself and she actually seemed to remember me (from the e-mails). I confirmed that she really did remember me (or she faked it quite well) at the end when she signed a copy of her book (that I won) - she asked me if I spelled my name with one "t" or two? Cool! BTW - do you know anybody named "Mat?"

When the DJUG Prez asked if anyone was looking for work, I raised my hand and said a few words about this site and Roller. I doubt anyone will find this site though; I didn't see anyone writing my domain name down, and how the heck do you spell "Raible?" So to offer a little Google love, here are a few different versions: Rabel, Riable, Raibel, Raybel, Rable, Raybell. If I was really bold, I guess I could send an e-mail to the DJUG Mailing List. I think I'll have to pass though, I'm just not that forward of a guy.

The meeting was packed, probably a 100 people showed up - most they've had in long time from the way they were talkin'. It was at DU, my Alma Mater, so it was fun to visit the ol' stompin' grounds. I had Mini-Me with me and found the DU Wireless network, but it required VPN software to get in (and my old id/pass didn't work to d/l the software).

Sue was a good speaker and did manage to impress me with her Struts knowledge. I didn't know that she is a contributing author of the JSP and Servlets column at O'Reilly's OnJava.com, nor that she's got a list of seemingly great publications. I tried to give her a tip about XDoclet, but she said she already knew about it and was planning on mentioning it in her preso. Doh! She really put me in my place. The best part of her presentation (for me) was the declarative exception handling, which I tried to implement on my current project, but it was too immature and buggy at the time. I think it's time to re-examine and refactor.

As a service to my readers, and possibly to readers from the meeting, here is a whole posse of good Struts links:

• XDoclet Struts Tags (see Tag Reference for @struts)
• Struts Mailing List and Archive
• Struts Newsgroup (duplicates mailing list)
• About Struts at husted.com, Tips, Catalog
• Learning Struts 1.1
• Struts 1.1 (PDF) by Chuck Cavaness Atlanta JUG
• Display Tag Library - awesome for pageable or sortable lists

I'd love to see some weblogs published by Sue or Chuck (Cavaness) - it'd be great to see more Struts Evangelists in the blogging community. The next meeting should be good. Marc Fleury, founder of JBoss fame is going to be speaking.

Handling Time Consuming Requests

Domininic says, "I am try to find a good way to have an intermediate page load up while my Struts Action performs a large database query and then XSLT transformation." Ask and ye shall receive. I received the following e-mail from Alec Missine a while back. The attachment has a method of implementing a TCR. Let me know how it works as I haven't tried it myself.

----- Original Message -----
From: Alec Missine
To: [email protected]
Sent: Monday, January 07, 2002 3:59 PM
Subject: processing time consuming requests (was: wait page primer)


There's been some interest to the message I posted last month on the subject. The war file was too big though, so I compressed the stuff as much as I could. I also added some javadoc and UML diagrams.

The attached Struts-based application prototypes the wait page support for a time-consuming request (TCR). When a TCR (e.g., a database search) starts, the appropriate wait page is being sent to the browser after the request's ETC (Estimated Time to Complete) expires.

In the meantime, the corresponding action (the database search) is being started in the background thread on the server. If the default ETC is used (ad infinitum) or the action completes before the request's ETC expires, there is no wait page at all - the browser gets the result page right away, while the background thread is still busy closing the resources.

The wait page has javascript that polls the server to update the wait page with the TCR's progress. When the TCR completes, the wait page is being replaced with the appropriate result page.

This implementation has been tested on Apache Tomcat 4.0 with an Oracle 8.1.6 database as a data source. Presently, the application provides read-only access to all database tables for all database schemas through extensive use of the java.sql.DatabaseMetaData object. The next release will support insert/update/delete functionality.

Alec

Attachments: tcr.zip (114 KB)

Hope this helps!

Struts Kick Start

Kevin Bedell and James Turner have setup Struts Kick Start; A site devoted to discussion and support of the Struts web application platform, centered around the SAMS book.

Tomorrow night at the Denver Java User Group, Sue Spielman explains how to use Struts to build Enterprise Applications. I think I know most of what will be presented, but it never hurts to attend a Java User Group meeting. We'll have to see how Abbie and Mom feels about Daddy taking off for a few hours (Julie has the flu, so I doubt I'll make it). I actually contacted Sue a few weeks back about contracting prospects. She responded quickly and opportunities seemed promising after exchanging a couple of e-mails. But alas, I haven't heard from her since.

Struts now produces XHTML?!

I logged this bug many moons ago (December 19, 2001) - and tonight it appears to have been fixed!! This is sweeter than all getout in my opinion. This means that adding <html:html xhtml="true"> to the top of your JSP when using Struts will render XHTML-compliant markup. I haven't tested it yet - thanks David Graham!

Struts Goodies.

I went searching on the Struts User List this afternoon and found a couple treats. The first is that you can make $135 for each Struts bug you fix. The second is StrutsCX (Struts with Castor XML and XSLT - but without JSP.). Sounds cool, downloading now.

Update: I installed StrutsCX on this server so you can try it out. Pretty cool stuff. I wonder how difficult it would be to switch from Castor XML to Castor JDO, and then generate the whole thing using XDoclet. BTW, did you know you can install WAR files in Tomcat by 1) ftp-ing the file to your server, and 2) using a url in your browser? Pretty cool - here's the one I used to install simpleweb today:

http://raibledesigns.com/manager/install?path=/simpleweb&war=jar:file:/home/raible/webapps/simpleweb.war!/

A Tutorial.

Struts meets Swing. Thanks Erik. I hope that I never have to use this. I dread that day that I have to write a Swing app over a web app.

JSF Chat now at 11:00 a.m. MDT tomorrow.

It looks like they decided 6:00 AM was too early for me - now at 11:00 AM PDT - that's 12:00 noon for you mountain timers.

JSF Commentary.

Brian Pontarelli has written an article about the recent Java Server Faces specification from Sun. I received an e-mail from him this morning via the Denver JUG - a little search on Google seems to indicate he works for BEA.

Struts and XDoclet.

The last release of XDoclet has many more Struts-related features; such as building your validator.xml file and support for adding plug-ins to your struts-config.xml. It seems that a lot of work has been done by Erik Hatcher to make this happen. Is this the same Erik Hatcher that wrote the Ant book I'm reading? I think so. Erik sent this e-mail to the struts-dev mailing list this morning with a brief how-to on integrating XDoclet and Struts.

Apache moving from Bugzilla to Scarab?

I think it's true. While trying to remember Struts' URL for bugzilla tonight, I typed in nagoya.apache.org. Good stuff found there. Why was I going to Bugzilla for Struts? Because I don't think Roller is listed as a Powered by Struts site. This e-mail turned me on to this fact. This site is on there, but only because of Roller - so I figured I'd enter a bug for it.