Spring 3.0 & Maven

I wanted to go over the process of upgrading the build from Spring 2.5 to Spring 3.0 (3.0 release announcement) using Maven for the build process. For almost all applications from basic dependency injection to webapps, and even enterprise applications with Spring Web Services and Spring Integration all upgraded without any issues.

I did change all the builds to use the SpringSource Enterprise Bundle Repository. It has all the Spring projects and also repackaged versions of many other open source ones. SpringSource did this to make all the artifacts OSGi enabled and also corrected any errors in dependencies where possible. It isn't necessary to use this repository and all Spring projects are also deployed to the main Maven repository tool.

I primarily switched so the projects could be more easily imported into an OSGi environment if someone needed to the SpringSource Enterprise Bundle Repository (EBR) and to avoid any dependency resolution issues since some artifacts will need to be resolved from the EBR.

Keith Donald, from SpringSource, did a blog discussing using Maven with Spring 3.0. It's called Obtaining Spring 3 Artifacts with Maven and is definitely worth reading to understand things in more detail.

Spring & Spring by Example

I've been working a lot on getting Spring by Example updated for Spring 3.0. A Simple Grails Webapp was also added to this release.

Almost everything is upgraded except for the AspectJ LTW example, GWT ones, and OSGi. The AspectJ one, I've had an odd problem that I've updated everything to use the Spring Repository, but when I change it to from Spring 2.5.6 to 3.0, the weaving stops working. No errors and no success resolving the issues, but I will keep working on it. I had trouble with the GWT webapps too, but I think it's mainly build related. I'll probably start over with a new project using GWT 2.0 and build the examples back up. For the Spring dm Server (OSGi) ones, I just haven't had time. I don't think there will be a problem upgrading them.

Everything is versioned on the site, so all past site releases and examples are available (Spring by Example 2.5.x, which is version 1.0.3). Just follow the subversion instructions at the end of the examples to checkout the correct version of the project the example describes. If you're ever not sure what version of something the example uses, check the 'Project Information' section at the end of the example and/or the Maven POM.

I have a Spring Roo example in progress that is the basis for a simple person and address example. Ideally I'd like to even use Roo to replace many of the webapp examples and/or have as much of them generated as possible. I'd also like to spend time redoing the web services add-ons for Roo and get them into a releasable state, but I just haven't had the time. I'm hoping it will fit in with a future project soon, so maybe it will get done.

I also plan on getting SpEL, REST, and some other examples together for the website. I've also done a lot of Flex work over the last year, so I'd really like to do some more advanced Flex examples and especially a basic messaging example and security example.

Spring Roo, SpringOne 2009, Spring by Example

I haven't been active on my blog or Spring by Example for a long time. I was just really busy. In that time I've been working with Flex, Spring BlazeDS Integration, Spring MVC, Spring Web Flow, Spring Roo, and other things.

Spring Roo was very useful. I made my own add-ons that generated web services based on a JPA bean and even the matching ActionScript class. I'm going to try working on a better version based on the new Spring Roo add-on format when I have time. What I did so far is checked into subversion. It was developed against Spring Roo 1.0.0.RC1 before there was standardized add-on format. I was very rushed when I did this, so it's functional but very basic and needs to be redone.

SpringOne 2009 in New Orleans was good. A lot of interesting presentations and nice getting to see different people again. The cloud presentation in the keynote was very interesting. Some of the improvements in Spring MVC that are in Spring 3.0 are quite nice. There is JSR-303 (Bean Validation) support, Type Conversion and Validation (blog by Keith Donald), REST support, and an MVC namespace for reduced configuration. Some of the SpEL (Spring EL) integration with other projects like Spring Integration and Spring Security look really useful. SpringOne is a really good conference and I'm glad I went.

I've been working for over a week on upgrading Spring by Example's projects to Spring 3.0.0.RC3. Most have upgraded without any issues, although I'm having trouble upgrading the GWT ones. I'm going to probably leave them and the dm Server (OSGi) examples as they are for now and finalize the other examples, double check everything is working, and update the documentation so I'll be ready for a release for the Spring 3.0 final release. The webapps (other than GWT & dm Server ones) have not only been upgraded to Spring 3.0, but have also been upgraded to JPA and following Spring MVC best practices as much as possible if they weren't already. All of them were changed to use the Spring MVC namespace which reduced their configuration slighlty. Also the applications with security had their login/logout pages changed to be served through Tiles and support i18n. When I have time I'd like to change the webapps to use jspx and use RESTful URLs.

I'm hoping to get a release of Spring by Example out in the next few days. Then continue working on everything else and possibly have another release before the end of the year. I'd also like to get a SpEL and Spring MVC REST examples added to the site.