Raible Designs

Maven 2 Alpha - looking good!

I saw that the Maven 2 Alpha was released today and decided to give it a spin. The two features in Maven 2.0 that look compelling to me are 1) speed and 2) transitive dependencies. I've been using Maven 1.x on my current project since January and I still don't like it. Why? It's dog slow on my PowerBook (but tolerable on my Windows box) and you have to specify a shitload of dependencies when developing an app with Struts+Spring+Hibernate.

Maven 2 looks good, and it does seem to startup as fast as Ant (at least on Windows). Just typing "m2" completes in about a second, and so does typing "ant". Typing "maven" takes about 3 seconds (even though it reports it only took 1 second). I look forward to seeing Maven 2 evolve. I wonder if we should rewrite our POMs for Maven 2 (we current have 11 sub-projects)? We'd probably be a pretty good test-bed, but I don't think Maven 2 supports all the 1.x plugins - does it?

I doubt I'll use Maven 2 with Equinox or AppFuse this year - mostly b/c I don't expect it to be released until 2006. I do like the looks of Ivy and I've considered re-writing AppFuse's monstrous build.xml file using JAM. If I were to use Ivy, I think I'd still release with all JARs in a local "lib" directory. The nice thing about Ivy is it would give users the option of checking JARs into source control (currently, it's required).

Even after using Maven for several months, I still like local JARs better than downloading. It does make a lot of sense in a multi-project environment though.

As for JAM, I don't like it for two reasons: 1) it uses the non-transitive dependency listing like Maven 1.x and 2) it requires you install JAM and set a $JAM_HOME. I'd prefer to keep AppFuse to one build tool - Ant or Maven (or both).

I suggested a large refactoring of the build process (and collapsing of the source trees) for AppFuse 1.9, but it was rejected by users for the most part. Their opinion: the build process works great, we like it - work on other stuff that's more important (code generation, tools support, etc.). Another thing that's suprised me about AppFuse users is the relatively small number of folks that have requested support for appservers other than Tomcat. To date, I don't think I've had a single Resin or Orion request, but I've had plenty of WebLogic, WebSphere and Sun App Server requests. The most compelling reason to use JAM for building/deploying/testing AppFuse is for its server support, but if I don't need it, why add the complexity?

I guess some things just work, and there's no reason to fix them if they aren't broken. Maven 1.x is not one of those things IMO. It's good to see the improvements coming in Maven 2.

Cool Web Cam

A co-worker pointed out a pretty cool webcam today. It's called the Cupola Cam and it displays live shots from a camera in Littleton, Colorado. The coolest part is you wait in a queue for full-control of the camera, and then you can move it around to look at everything. Nice use of Java technology too (it's an applet).

Open Source CMS based on AppFuse

If you're looking for AppFuse examples or a Java-based CMS (Content Management System) - you might want to checkout AtLeap.

Blandware AtLeap is a multilingual free Java CMS (Content Management System) with full-text search engine. Blandware AtLeap is a framework which allows you to rapidly start your own Web application.

The screenshot looks pretty cool. According to Andrey Grebnev (the project's owner), this project is based on AppFuse 1.5 with pieces from 1.6.

Upgrading to Spring 1.2 RC1 and Hibernate 3.0

I spent an hour or so on Friday upgrading Equinox and AppFuse to use Spring 1.2 RC1 and Hibernate 3.0. The upgrade for AppFuse was relatively painless, but the upgrade for Equinox failed. Equinox uses HSQLDB version 1.7.1. The main reason I use the 1.7.1 version is to avoid the infamous "lock exception" that the new HSQL version throws in standalone mode. With version 1.7.1, it seems you could have more than one connection open to the file-based database w/ no problem. I really like this feature in 1.7.1 b/c it means you can run the app in Tomcat and browse the database at the same time.

So what's the problem? Why can't I just use Hibernate 3.0 with HSQL 1.7.1? The problem is I like using the following setting as part of my "sessionFactory" bean:

<prop key="hibernate.hbm2ddl.auto">update</prop>

This setting will update the schema when you change mapping files, but otherwise leave the data intact. Furthermore, it'll actually create the tables if they don't exist. Not so with Hibernate 3. With Hibernate 3, using "update" doesn't create the tables. Of course, upgrading to a newer version of HSQL fixes the problem, but then I get the lock problem. My eventual solution will probably be to hack Hibernate or HSQL, but for now I just won't upgrade Equinox. Another solution might be to look at some other embedded databases. Of course, I could also require users to install a database to run Equinox - but I like having the "no setup required" feature.

Regardless of the problems I experienced with HSQL and Hibernate 3, upgrading AppFuse was pretty painless. Here's the set of instructions I sent to the mailing list:

1. Download Hibernate 3.0 and Spring 1.2 RC1.
2. Create a lib/spring-1.2-rc1 and put the following files in it (NOTE: spring.jar now contains aopalliance.jar):

       acegi-security-0.8.1.jar
       commons-codec.jar
       ehcache-1.1.jar
       license.txt
       spring-mock.jar
       spring.jar

3. Create a lib/hibernate-3.0 and put the following files in it:

       hibernate3.jar
       lgpl.jar
       lib/antlr-2.7.5H3.jar
           antlr.license.txt
           asm.jar
           c3p0-0.8.5.jar
           c3p0.license.txt
           cglib-2.1.jar
           dom4j-1.5.2.jar
           jta.jar
           jta.licence.txt
           oscache-2.1.jar
           swarmcache-1.0rc2.jar

4. Change the versions for Hibernate and Spring in lib/lib.properties. Also, change the hibernate.jar property to reference hibernate3.jar instead of hibernate2.jar.
5. In build.xml, change the "package-web" target to include all the Hibernate JARs instead of just specific ones:

   <lib dir="${hibernate.dir}/lib" includes="*.jar" excludes="jta.jar"/>

6. Change web/common/taglibs.jsp to use uri="/oscache" for the oscache taglib.
7. Search for "net.sf.hibernate" and replace it with "org.hibernate".
8. Search for "orm.hibernate" and replace it with "orm.hibernate3" (for Spring).

The major difference for Hibernate is you no longer need odmg-3.0.jar, but you do need asm.jar and antlr-2.7.5H3.jar. Let me know if you find any issues with these instructions. You could also just download AppFuse from CVS.

NOTE: The CVS version of AppFuse has an XDoclet version that only supports generating Hibernate 2.x mapping files. I believe there is support for Hibernate 3 in XDoclet's CVS - but I haven't had a chance to upgrade yet.

Update: Here's more on the HSQL bug that's not really a bug (according to a comment on the post). Regardless of whether it's a bug or not, it'd be nice to have the 1.7.1 behavior as an option - it's a great feature for get-started-quick apps like Equinox.

RE: Going to work for Microsoft

You know you're good when your April Fool's joke gets picked up by a major news site.

With a fair bit of attention being given to using older Web technologies to create new Net applications, Microsoft is apparently looking to make sure it is staying up to date. The company has hired Java specialist Matt Raible to help make sure that Ajax is in Visual Studio's cupboard of tools.

Going to work for Microsoft

I received a fair amount of feedback from yesterday's post. A few folks sent e-mails asking me to partner with them to start a company, and a couple of companies called claiming they could set me up with my "dream job". The call I didn't expect was from Ashwin Karuhatty of Microsoft. Ashwin is the Developer Evangelist that invited me to the Developer Summit in Redmond a few weeks ago.

He offered me a position with Microsoft being a Developer/Evangelist working on the Visual Studio Team to integrate Ajax-ish components into .NET. I've been doing a lot with Ajax stuff lately, and really enjoying myself, so I've accepted the position. I just submitted my two-weeks notice to my Project Manager and will become a Microsoftee on April 11. For the first 2 months, they're going to let me work out of my house, with an eventual move to Redmond, WA. I'm pretty excited about the move - both my parents and my sister live w/in 4 hours of Redmond. Sure it rains a lot there, but having family so close should make up for that.

If you have any suggestions for Ajax Components in Visual Studio, let me know!

Ditchnet.org: JavaScript tips and a cool Tabs Tag Library

Thanks to a post to the Struts Menu Mailing List, I discovered a nice blog about JavaScript and DHTML. Not only does it seem to have lots of good tips and tricks, but its author also has a couple of cool menu examples:

• JSP Tabs Taglib
• Nice DHTML Dropdown Menus

Nice work Todd!

Trim Spaces in your JSP's HTML

One of the annoying things about JSPs is all of the dynamic (non-rendered) parts of the page still produce line breaks. This means that if you do a view-source, you'll likely see large blocks of whitespace.

The good news is you can get rid of this whitespace if you're using Tomcat 5.5.x. Just locate the "jsp" servlet in $CATALINA_HOME/conf/web.xml and add the following <init-param>:

    <init-param>
        <param-name>trimSpaces</param-name>
        <param-value>true</param-value>
    </init-param>

I tested it and it works great. This begs the question - why isn't this on by default? Source: Struts Mailing List.

Update: JSP 2.1 adds the ability to trim whitespaces.

Spring Live is done, but constantly improving

I've talked to a couple of Java developers lately that asked me "Sooo, when are you going to be done with Spring Live?" I was quite surprised to hear this because I finished it in October. I guess folks just aren't used to the constantly updated thing. Or maybe SourceBeat needs to do better marketing?

Regardless, Spring Live has been a blast to write. I was definitely hesitant when I signed up to write it b/c I didn't know much about Spring. But a year later, it seems to be getting good reviews and holding it's own when compared with the other Spring books. I'm also starting to see some traction from the book itself - not only in book sales, but also in training and invitations to speak at conferences.

If you're looking for Spring training, don't hesitate to contact me or SourceBeat directly. Also, the Spring Developers offer Spring training as does Rick Hightower.

How IE handles PDFs

From the Struts User Mailing List, I spotted a good explanation of how IE handles PDFs. It's quite messed up, so I thought I'd post it for your amusement.

If your application returns data that is to be handled with an ActiveX control (ie Adobe Acrobat Reader) the browser sends additional requests to the server. In IE 4.x and 5 it actually sends three requests. For IE 5.5+ it sends two.

Assuming that your using IE 5.5+, the first request is the original request (duh), but then IE sends a second request to get the content-type. Who knows why they can't figure this out on the first request This second request has it's userAgent header set to "contype". You can solve this problem and increase the performance of your application by writing a Servlet filter that sits in front of whatever Actions you have setup to serve PDF content. Have this filter look at the userAgent header of each request. If it's set to "contype" just send an an empty response back to the client with the content type set to "application/pdf". Simple as that.

More info on this "feature" is on Microsoft's site.