This is the second of a four part series comparing Seam and Spring Web Flow (SWF),and looks at the Spring implementation of the sample application that we discussed in part 1. In a day or so I will have the piece that looks at writing the application using Seam.
This is the first of a four part series comparing Seam and Spring Web Flow (SWF) from different aspects, primarily with respect to building web based CRUD applications. It includes writing a simple but fairly complete application using both frameworks and then comparing the differences between the Seam and the SWF implementation.
This first part starts by taking a look at the two frameworks, where they come from and briefly, how they are used.
In this post I talked about how the Java standards are important to ensuring java has a long and fruitful life. This post references Spring as an example but was written before the fallout from the Spring licensing issues. This fallout tends to back up the argument that standards are important, although since there were no standards at the time for Spring to follow, it is not a totally valid position.
Over the years, many people have been knocked for claiming that Spring is a proprietary framework. How can it be when it is open source would often be the argument. Proprietary in its literal sense means that it has one owner or controller which is true for Spring for the most part. A less formal definition when discussing programming, Java in particular, is that it does not follow any open standards. Spring broke a lot of new ground which in many cases, meant that there were no standards or only bad standards to follow. However, a number of developers also bought into using other Spring features like the Templates to aid them in their development.
Now that Spring has penetrated developers code to a large degree, vendor lock in was in place for many companies with large spring based projects and Rod and Co turned off the free beer once everyone was hooked. Again, it’s their business, their platform, and they can do with it as they like.
However, if the Java platform had a set of good standards for defining framework functions, then nobody would seriously bother with a non-standard framework, and nobody would be able to shut off the tap because they could be replaced in an instant by an alternative implementation of the standard. Again, this reinforces the need for good standards (like EJB3.1 appears to be) and also for timely updates to the standards.
Reading this post on Javalobby prompted me to go and dust off a post I wrote a while ago but hadn?t published regarding Spring and the revitalized EJB standard. At the time I was fired up by this post by Rod Johnson which seemed to be a large helping of FUD and insults. Nonsense such as suggesting that because some people were using app servers and some weren?t the age of the app server was over, like suggesting that because I want a shovel to dig a hole, we no longer need backhoes. This was interspersed with some irrelevant quotes from Gartner made to look like evidence and malicious comments about EJBs and their users. It seemed like the Spring folks were chomping at the bit to pronounce EJB dead when in fact, as evidenced by some recent posts, it is very much alive. In hindsight, it seems the Spring guys were trying to lay some marketing groundwork prior to releasing their own OSGI application server.
This brings me to this latest post, one of a number of recent posts which sings the praises of EJBs and in this case asks the Spring developer “why not?”. It’s almost like the question nobody asks because the presumption is that the answer is obvious. It also touches on the issue of Spring and EJB developers not getting along which I think in part was fueled by the old arguments of Rod and Gavin who seem ‘passionate’ about their technology choices. However, there is still some animosity between the two camps years after those minor flame wars. I think part of it stems from the normal response of users being defensive, and therefore offensive or protective of their technology of choice because of flaws they are aware off even if they disagree with them, which is a normal response.
Disclaimer : I’m currently working on a Seam project and have been involved on the Seam forums. However, when I need a quick dependency injection library (especially for SE), I turn to Spring.
EJB users are having to defend a technology which has the appearance of being stodgy and has a terrible legacy even though its modern day incarnation is far more hip, cool and even Spring-like. Few negative comments about EJBs appear to be about flaws in the current implementation other than the fact that EJBs require a container.
The Spring users have to defend a technology that is in essence proprietary as opposed to standards based, and while the core Spring functionality (DI, AOP) is very good, a number of people believe that it is starting to spread itself a little too thin, and starting to suffer from the dreaded ?Bloat?. It is now facing competition from EJB, a technology that is not only as easy to use and powerful but is also a standard, which, all things being equal, is a positive. If nothing else, being a standard will also give it a helping hand in being adopted in some of the more corporate shops.
While SpringSource haven?t implemented the standards, I?m sure there will be a Spring driven implementation of Web Beans (JSR 299) which could drag Spring kicking and screaming under the standards umbrella. If Web Beans gains traction and becomes the accepted way of defining components for web applications, then there is a chance people will choose the standards based web beans syntax over a proprietary Spring syntax and be able to swap out implementations. One advantage Spring does have is the ability to provide its core functionality on both desktop and web applications which unfortunately, isn?t a part of the Web Beans spec (yet?). This may provide enough reason for developers to avoid using Web Beans or at least limit it to pieces that will definitely be web based only.
I do like the fact that the only opaque part of Spring is the container. Other pieces like the transaction manager, data sources and so on are all transparent for you to see in your configuration unlike the EJB container where they are just bundled in and magically mess with your beans. This lack of apparent simplicity can also be a turn off for some people who prefer a simpler Spring solution over complex old EJBs.
In some ways Spring feels like that small cafe that worked really well, was cheap and served great food compared to ‘those chains’. They decide to open a couple more restaurants up, and the owner can’t run all of them so he hires extra help, and trains them, but they don’t always get it right, and lack the enthusiasm with personal service. He opens a couple more stores up and decides to produce a manual detailing every aspect of the recipes and customer service. Before he knows it, he is one of ‘those chains’, and the quality of food has gone down, and the prices have gone up. Not that I think every Spring project is prone to fail unless it is under the guiding hand of Rod. However, Spring has spread beyond it’s core functionality and expecting the same level of buy-in from developers, and from Rod’s post referenced at the beginning of this post, it seems they are even trying to Manufacture buy-in.
At one time, the Spring team would have criticized the inability to move a ‘standard’ EJB from one app server to another, now they just expect you to deploy applications in their proprietary modules for their app server. They would have criticized the bloat of the implemented standards, and now if you want to use their web flow API, you have to include their Web MVC framework even if you are using JSF. I think this is a bit of a reach from the SpringSource folks. Just because I put my Dependency Injection egg in your basket, it doesn’t automatically mean I’m going to put my view technology and server choice eggs in there too.