Dan Allen

CDI and Seam 3 are the Future of Both the Seam Community and Red Hat.

Jessica Thornsby

In the second installment of our interview with Dan Allen, we find out what Java EE 6 means for the future of Seam.

In part two of our interview with Dan Allen, Jan Groth and
Andreas Eigenmann ask him where Seam 3 fits into the Java EE 6
picture, and find out whether there are any plans for a ‘Seam in
Action’ sequel……

Jan Groth: I’d like to switch to some more
technical issues. Looking at the exciting new features of Java EE
6, like CDI, bean validation and JSF 2.0, a Seam developer will
recognize many of these concepts from Seam 2. Has it been a
strategy, to get these core ideas standardized?

Dan Allen: Absolutely. Jay Balunas, the
RichFaces lead, had a great way of describing our strategy:

“Find a void. Fill the void. Standardize the fill.”

Red Hat is strong when the Java EE platform is strong. Our
strategy does not depend on the platform remaining weak to justify
the existence of our projects. It’s quite the opposite. If we make
one of our own projects obsolete, or some part of it, that’s
progress. Then we look for the next area to improve (there’s a
perpetual queue.) If anything, we are the ones that really push
this platform to reach its full potential. We invest in this cycle
because JBoss has always been about choice: a low barrier to entry
or exit. We want to be selected based on merit, expertise,
leadership and a commitment to standards and openness. Not because
you need our liferaft to use Java EE.

That’s only part of the story. In order to standardize these
core ideas, the JCP has to be willing and able to allow it to
happen. Not only do we bring ideas to the JCP to standardize, we
also bring our principles of openness and transparency. We’ve
worked hard, and continue to work, to make the JCP a
community-driven organization. Admittedly, we have a long way to

Seam 2 affected all of the specs you mentioned above. The core
of Seam evolved into CDI. Hibernate Validator and its integration
with JSF went into Bean Validation and JSF 2.0 respectively. And
about half of the JSF enhancements in Seam, and other
recommendations in Seam (e.g, Facelets,) became standardized in JSF
2.0. And Java EE 6 in general adopted Seam’s minimal configuration
and minimal layers spirit. It was a huge step forward and certainly
Seam 2 developers will be right at home in the Java EE programming

Speaking of Seam and how it fits with Java EE 6…

Jan Groth: Some people are saying that Java EE
6 is “enough” and Seam 3 isn’t really needed any more. What would
you say to those people?

Dan Allen: Seam’s mission statement remains the
same: To provide a fully integrated development platform for
building Internet applications based upon the Java EE

Java EE 6 is a tremendous step forward for the platform. It’s
the first revision that I can bring to a talk and, with a straight
face, show the audience that you can build an application with it
without any add-ons (i.e., liferafts.) In fact, it’s significantly
better than the core of Seam 2, both in design and performance.
There is a commitment to type-safety across Java EE 6 and that
means stronger tooling, more robust code and less coding errors.
And so much is calculated at application startup, that the runtime
impact is close to zero.

The application servers are also so lightweight now that you
should strongly reconsider your reasoning for using a Servlet
container. As I like to say it, “Don’t settle for a Servlet
container.” I say that because it’s like having to bring your own
beer to the party. The environment has gaps. The introduction of
the web profile closes the gap between the efficiency of a Servlet
container and the full featured application servers, hitting the
happy medium where developers can be productive and have all the
key technologies that they need to create enterprise web

However, if I told you that you could develop an entire
application without a single third-party library, I’d be lying to
you. Just like a house, you will need to furnish the platform in
some places. Some of it just wasn’t standardized in time or
addressed at all (*cough* security,) some of it still needed more
thought and there are many things that simply cannot be
standardized because of licensing (e.g., PDF creation) or it’s too
specialized (BPM or rules engines). We don’t want Java EE to be a
dumping ground for technologies. But it’s not totally spartan,
either. You can think of it as a model home. You can move right in
and start living, but eventually you will find needs that are
unique and you’ll need to customize it. That’s where the Weld
extensions and Seam 3 comes into play.

There’s going to be one very important difference this time
around, though. Seam 3 is going to be modular and portable across
Java EE application servers and servlet containers from the start.
If you are a JSF user, you can think of Seam 3 modules as more like
UI component libraries in how they fit into the platform. This
portability will be ensured through three guarantors:

1. Seam 3 is primarily built on the CDI portable extension SPI,
insulated from handling low-level concerns that run a high risk of
breaking portability.

2. One of the principal requirements of Seam 3 modules is

3. The Arquillian in-container test framework allows modules to
be continuously tested against an array of application servers.

Is Java EE 6 a solid platform? Yes. Will you still need
extensions? Yes. And CDI was designed specifically to be able to
root and foster such an ecosystem. You can even write your own
extensions, which really wasn’t possible with Seam 2. Now we just
need a plug-in site ;)

Jan Groth: Say I’m a software architect looking
for an enterprise framework for my next web project. I heard a lot
of good things about Seam, but I feel a bit torn between at least
three options: Use Seam 2.2 on Java EE 5, use CDI / Weld on Java EE
6, or wait for Seam 3. Is there any advice you could give me?

Dan Allen: That’s always a tough question
because you don’t want to leave anyone out. I certainly wouldn’t
have written a book about Seam 2 if I didn’t think it was something
pretty compelling and productive. If you are preparing an
application for immediate deployment to production, you are
comfortable with Seam 2 or you want to be able to use the Red Hat
Enterprise Application Platform (EAP), then you should strongly
consider Seam 2. You might also like Seam 2 because its rules for
injection and state management are a lot less strict than CDI. But
know that CDI and Seam 3 are the future of both the Seam community
and Red Hat. So even if you are using Seam 2, you should be
spending time researching and learning Java EE 6 and Seam 3. If you’re
to make the move to Java EE 6, which I highly recommend for early
and more flexible adopters, you don’t have to wait for Seam 3. It’s
happening now. There are alpha releases of several modules
available and many more will be ready by summertime. If something
is missing, it’s really not that difficult to write a CDI extension
to fill the void in the meantime. Heck, it might even get you
involved in Seam 3 development.

Jan Groth: As an interested developer, is there
a chance to contribute to Seam? What would be a good starting

Dan Allen: Absolutely. The best place you can
go is the Seam 3 website. We’ve spent a lot of time laying out a
very clear map of all Aspects of Seam 3, from using it, to
contributing to it. I recommend that you read up on the ways to get
involved and find what works best for you. If something is unclear,
please let us know either on the forums or the mailinglist. We are
eager to make the instructions as lucid as possible. In fact, it
sounds like something I need to blog about.

To post on the forums, you first need to create an account.
If you haven’t done so already, we also encourage you to create an account at
so that you can establish a profile, connect with other
developers and post to related projects and use JIRA. If you want
to get coding right away, you can either browse JIRA for a feature
request that interests you or browse the modules page to see if there is a module you either
want to join or help lead.

As I mentioned before, we don’t just want Seam to be a framework
you get for free. That’s not Open Source. We want it to be open and
collaborative. We want you to feel ownership, however you may fit
in. There are no closed doors and there are no dumb ideas, as long
as they are backed by a real need. (However, people may not always
like your ideas, so come ready to defend them when necessary.) We
not only aim to be the best framework for developing internet
applications in Java, but also the most fun.

Jan Groth: Dan, you are the author of ‘Seam in
Action,’ one of the most highly regarded books on Seam – are there
any concrete plans for a sequel?

Dan Allen: Thanks. I wrote the book because I
had been told I had a very unique and in-depth way of explaining
the topic and I knew that if I could tell my story, it would
benefit a lot of developers. I’m grateful to hear that it did. Even
for people who haven’t adopted Seam, I think the book shed light on
problems with the platform that needed resolving.

Are there concrete plans for writing a sequel? At this point,
no, the plans are not concrete. For one, I still think it’s too
early. We are only just beginning to find out what can be done with
CDI extensions. And I think a book that doesn’t cover the
extensions isn’t going to be a complete handbook for developers
like ‘Seam in Action’ has been. I also have to consider the impact
it will have on the project and the community. I am really enjoying
getting more involved with the community and, with Pete, guiding
the module leads. I can’t imagine how I would manage to fit writing
a book in between all of my initiatives. I think by the beginning
of next year, we will have lots of extensions out, things will be
humming along, and then the world may be ready for a sequel. I’m
also strongly considering having a co-author, not just because it’s
too difficult to do alone, but because I think people will benefit
from at least one other perspective (and I will keep my marriage.)
Whenever the book is written, people will be very happy to know
that there will be a much stronger emphasis on testing, now that we
have Arquillian for writing proper and flexible in-container tests.
And yes, since Seam 3 is built with Maven 2, and we have official
Maven archetypes for CDI and Java EE projects, the examples will be
built with Maven 2 (and seam-gen will no longer be a big scary Ant

I’m very excited about all the innovation that is taking place
in the JBoss Community right now and I encourage you to become a
part of it. You never know where it will lead, but I can guarantee
you it will open doors for you.

Jan Groth: Thank you very much for your

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