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As we have just released the first milestone of the Spring Data JPA project I'd like to give you a quick introduction into its features. As you probably know, the Spring framework provides support to build a JPA based data access layer. So what does Spring Data JPA add to this base support? To answer that question I'd like to start with the data access components for a sample domain implemented using plain JPA + Spring and point out areas that leave room for improvement. After we've done that I will refactor the implementations to use the Spring Data JPA features to address these problem areas. The sample project as well as a step by step guide of the refactoring steps can be found on Github.

JPA with RAD8

"Stop using Tomcat and wondering why JEE "doesn't work." You're doing yourself a big disservice. Start thinking about JBoss AS 6, or GlassFish v3 - Yes, I know, it's a "Full JEE Container," - it's "Heavy," but with JEE6, that's not a bad thing: It all "Just works" and it works really well. Trust me, the reason people have thought Java EE sucks, is because they try to do this stuff on Tomcat, and say "Why doesn't (JPA, JMS, JTA, EJB, JSF, CDI) work?" Well… that's because Tomcat only gives you Servlet - the Request/Response lifecycle. So people install all these things manually, or try to, and then say, "Wow, Java EE is really hard to use, shit, I'm gonna use Spring or Grails instead.""

A step by step tutorial on adding CRUD (Create,Read,Update,Delete) capability on Spring MVC using Hibernate JPA.

"Texo provides JPA annotations, model and template driven development technology powered by EMF for web application (WAR) development projects. Texo uses components currently present in the Eclipse Modeling Framework (EMF) and Eclipse Modeling Framework Technology (EMFT) projects. Texo is a proposed open source component in the Eclipse Modeling Framework Technology (EMFT) project. "

Querydsl is a framework which enables the construction of type-safe SQL-like queries for multiple backends including JPA, JDO and SQL in Java. Instead of writing queries as inline strings or externalizing them into XML files they are constructed via a fluent API. Code completion in IDE (all properties, methods and operations can be expanded in your favorite Java IDE) Almost no syntactically invalid queries allowed (type-safe on all levels) Domain types and properties can be referenced safely (no Strings involved!) Adopts better to refactoring changes in domain types Incremental query definition is easier Querydsl is licensed under the LGPL 2.1 license.

Last weekend while pondering the question "Is Scala ready for the enterprise?" I decided to write a simple Java EE 6 app entirely in Scala, without using any Java. I had three main reasons for doing this: one was just to see how easy/difficult it would be to write everything in Scala (it was easy).  Another was to document the process for others journeying down the same road (the entire project is on github).  Finally, I wanted to identify advantages of using Scala instead of Java that are specific to Java EE apps (I found several). Background The specific app I created was an adaptation of the Books example from Chapter 10 of Beginning Java™ EE 6 Platform with GlassFish™ 3. It's a simple web app that displays a list of books in a database and lets you add new books. Although it's a pretty trivial app, it does touch on several important Java EE 6 technologies: JPA 2.0, EJB 3.1 and JSF 2.0.

Hades is a utility library to work with Data Access Objects implemented with Spring and JPA. The main goal is to ease the development and operation of a data access layer in application

Does it all make sense now? Do you know how to solve every problem? Probably not, but when it comes right down to it, using Java EE can be even simpler than using Spring, and take much less time. You just have to find the right guides and the right documentation (which is admittedly a severe sore-spot of Java EE; the documentation is still a work in progress, but is getting much better, save blogs like this one.) You have to turn to a vendor like JBoss, or IBM in order to get the use-case driven documentation you need, and they do have documentation, it's just a matter of finding it. Seam 3 in particular strives to give extensive user-documentation, hopefully making things much simpler to adopt, and easier to extend. The main purpose of this article was not to bash Spring, although I may have taken that tone on occasion just for contrast and a little bit of fun. Both Spring and Java EE are strongly engineered and have strong foundations in practical use, but if you want a clean programming experience right out of the box - use Java EE 6 on JBoss Application Server 6 - JBoss Tools - and Eclipse. I will say, though, that the feeling I've gotten from the Spring forums vs the Java EE forums, is that there are far many more people willing to help you work through Java EE issues, and more available developers of the frameworks themselves to actually help you than there are on the Spring side. The community for Java EE is much larger, and much more supportive (from my personal experience.) In the end, I did get my application migrated successfully, and despite these issues (from which I learned a great deal,) I am still happy with Java EE, and would not go back to Spring! But I do look forward to further enhancements from the JBoss Seam project, which continue to make developing for Java EE simpler and more fun. Don't believe me? Try it out. Find something wrong? Tell me. Want more? Let me know what you want to hear.

" Brings transactions and persistence to managed beans, provides a simplified transaction API and hooks transaction propagation events to the CDI event bus."

"This Tech Tip presents some of the features of inheritance supported in the Java Persistence API. A sample package accompanies the Tech Tip. It demonstrates some of the features discussed in the tip. The examples in the tip are taken from the source code for the sample (which is included in the package). The sample uses an open source reference implementation of Java EE 5 called GlassFish. You can download GlassFish from the GlassFish Community Downloads page."

Tuning Hibernate