What is it?
Sun Java System Application Server (SJSAS), the commercial
implementation of the
Glassfish community project, is moving up from a brash young
contender to a serious challenger to established application
servers from the likes of
Oracle, BEA and IBM.
SJSAS is a core part of the Java Enterprise System, supporting
development technologies such as
Java Studio Enterprise, Java Studio Creator and Netbeans 6.0
integrated development environment.
Sun Microsystems has the edge when it comes to new Java
releases, and Glassfish version 1 - the open source version of
SJSAS - was the first Java EE5 application server. Glassfish v1 was
strictly a developers' version. Glassfish version 2 and its
commercial counterpart SJSAS 9 update 1, released in September,
added enterprise-strength features, such as high availability and
scalability through clustering and replication.
The commercial and open source versions offer the same core
features, but SJSAS comes with services and several optional
bundles. Analyst firm Gartner says, "Glassfish is available as a
free 'use at your own risk' download. Sun's SJSAS is a certified,
supported and indemnified offering available by subscription or as
a perpetual licence."
Gartner describes Glassfish and SJSAS as "promising alternatives
to the current open source Java EE products", but as yet with
"limited industry production experience".
The free downloads and Glassfish community resources and support
provide an alternative skills acquisition route to Sun's own, very
expensive, training.
Where did it originate?
Project Glassfish was launched in June 2005. Sun donated SJSAS
version 8.x to the Glassfish community, hence the disparity in
numbering: Glassfish version 1 was SJSAS 9.0.
Oddly, Oracle, one of the application server market leaders, is
a major contributor to the project, donating its Toplink Essentials
persistence technology. Ericsson supplies the SIP Servlet
technology.
What's it for?
The clustering support in SJSAS allows servers to be grouped for
scalability and to replicate data in-memory for failover protection
and high availability. Application server clusters can be managed
from a central console.
The September releases also introduced support for
interoperability between web services running on Java or Microsoft
Windows. This uses the Project Metro web service stack.
The SJSAS 9.1 optional bundles include a graphical installer, to
be introduced to the community version with Glassfish 3, and a
high-availability ("99.999%") database as a stronger alternative to
the open source memory replication. This database is not yet open
sourced, and Sun's developer network site describes its
implementation and maintenance costs as "relatively high".
What makes it special?
Sun describes Glassfish as "the standard Java EE reference
implementation". Gartner describes "the large Solaris installed
base" as another potential strength.
How difficult is it to master?
Sun offers a one-day workshop for people already involved in
application design, deployment, administration, or support for
£400.
Where is it used?
As always with open source products, it is hard to know how many
downloads have resulted in production implementations. There are at
least 3,000 users of SJSAS worldwide.
What systems does it run on?
Solaris 9 and 10 on x86 and Sparc, Red Hat and SuSE Enterprise
Linux, Windows Server 2000 and 2003, XP and Vista.