Simple yet powerful
Initially, the switch to Java 5 appears to be one of the big topics of Spring 3.0. However, since previous versions of the framework have already largely supported Java 5, other topics are perhaps more significant.
The support of the increasingly important REST architecture further extends the new range of web features, first introduced in the previous version 2.5, and extends it to include a new operational context.
The Spring Expression Language offers new possibilities for creating more flexible Spring configurations. The potential impact of this approach is also demonstrated by the length of time the introduction of an expression language has been on the wish list of Spring users: The relevant feature request has a single digit number.
Conversations are directly supported in Spring. While this approach is technically required in the implementation of many web applications, developers often get by with holding the data within HTTP sessions, or through similar measures. Although conversations have been previously available in Spring Web Flow, their integration into Spring, makes them accessible to a much larger audience, while Spring Web Flow still adds a lot of additional valuable features.
Finally, the Spring developers tidied up some areas, like the build management and the project's structure. They even removed some obsolete features, to ensure that in the long run, Spring remains "simple yet powerful" .
Eberhard Wolff
is the Regional Director and Principal Consultant for SpringSource in the German-speaking world. He speaks at various national and international conferences and, among others, has written the first German language book about Spring.