William Vambenepe's blog

Spring’s Rod Johnson writes today about the future he sees for Java Bloatware (his unkind term for Java EE middleware). Of course, as Mr. Spring, he is far from neutral. Of course he is focusing on a certain class of applications (web-centered, mostly greenfield, which is a huge - and sexy - segment, but not in any way the only kind of applications). Of course he underestimates how established technology that works remains used long after it may have ceased to be the optimal solution for new developments. But even taking all that into account, he makes some good points about the proliferation of rarely-used capabilities in Java EE and the associated cost. Most of those points are well understood and are driving the more modular approach taken by Java EE 6. As well as the adoption of OSGi (see here and here for BEA’s example). In addition, as Rod mentions, the JCP now has to share the playground with other framework standardization efforts like SCA.

The most interesting part of Rod’s post from my perspective, is this prediction:

“The market will need to address the gap between Tomcat and WebLogic/WebSphere. Currently an important part of the market is neglected. The majority of Java web applications are most at home on Tomcat. A minority actually want some of the more esoteric functionality of a full-blown application server, such as JCA, or specialized capabilities such as distributed transaction management. But a larger minority need some of the operational and management features of those products, but are not interested in the esoteric APIs and the bloat they bring along with them. As more and more end user companies look to phase out legacy application servers in favor of better suited technologies, there will inevitably be a response to market demand, with products that hit the sweet spot and bridge this gap.”

Right on. This is the second time in a week that we see an acknowledgment of the importance of application manageability coming from SpringSource. Whether this mid-point demand will be met from the top down by a more modular Java EE stack or from the bottom up by building on top of Tomcat (or some non-Java HTTP server) remains to be seen. The two aren’t exclusive either.

I expect that the hosted application frameworks like the recently announced Google App Engine will also aim at that “more than Tomcat, less than J2EE” sweetspot. But the cost/benefit formula of a more full-featured (or “bloated” if you prefer Rod’s terminology) environment might turn out to be different in a “hosted framework” situation.

SpringSource has made some recent announcements, in an effort to build up its commercial offering on top of the open source Spring framework. There is now a SpringSource Enterprise subscription which gives you access to an “enterprise” edition of the framework, some support and the SpringSource Performance Suite.

The first two components (enterprise edition and support) are common approaches to commercial open source.

The performance suite is a new product, comprised of the Tool Suite (for development), an Advanced Pack for Oracle (for better use of Oracle RAC features) and the Application Management Suite (AMS). Application and middleware management is what I care most about, so AMS is the part of the announcement that caught my attention.

The only publicly-accessible source of meaningful information about AMS that I could find is this blog post by Jennifer Hickey. AMS is built on Hyperic. The monitoring is based on collecting, through instrumentation, entry and exit times for monitored methods. The agents then reports this to a server. Add to this some discovery capabilities and the console can then report observed metrics on the discovered/selected resources.

The blog post ends by saying that “we’d like to make it as powerful and easy to use as possible for both Developers and Operations staff”. At this stage, I think it’s a lot more likely to be used for development than for operations. The instrumentation overhead is supposed to be “very slight” but, as always with monitoring, this warrants more precise data. Also, it is not clear if/how AMS can integrate with other management tools.

In any case, it’s encouraging to see an open source application development framework which doesn’t entirely focus on ease of development but also acknowledges the full lifecycle of an application (and concerns such as monitoring, as addressed here, but also configuration management, governance, business activity management…). That’s the difference between “the best framework to create an application” and “the best framework to create an application that is expected to be used”. Before open source became a business strategy, a defining characteristic was that the developers where also users of the product. Which naturally meant that it was heavily biased towards developers and development tasks.

From an operations perspective, the AMS team should focus its efforts on application modeling, metric collection and management integration rather than the dashboard. A simple specialized console is great for application developers. The ability to discover, model, configure and monitor applications in conjunction with the other elements of the IT system (e.g. underlying infrastructure, end user experience, business processes and other forms of application integration, etc) is what operators really need.

In any case, it will be interesting to test the practical value of “Spring-aware” application management, above and beyond generic Java application management.

Bonus question: the enterprise edition of the Spring framework is “warranted to be virus-free”. Since the enterprise version includes the base framework, to the extent that the enterprise version is virus-free then mustn’t the base logically be “virus-free” as well? And what does “virus-free” mean anyway?

March starts next week and the middleware blogging bees are busy collecting OSGi-nectar, Spring-nectar, SCA-nectar, bringing it all back to the hive and seeing what kind of honey they can make from it.

Like James Governor, I had to train myself to stop associating OSGi with OGSI (which was the framework created by GGF, now OGF, to implement OGSA, and was - not very successfully - replaced with OASIS’s WSRF, want more acronyms?). Having established that OSGi does not relate to OGSI, how does it relate to SCA and Spring? What with the Sprint-OSGi integration and this call to integrate OSGi and SCA (something Paremus says they already do)? The third leg of the triangle (SCA-Spring integration) is included in the base SCA framework. Call this a disclosure or a plug as you prefer, I’ll note that many of my Oracle colleagues on the middleware side of the house are instrumental in these efforts (Hal, Greg, Khanderao, Dave…).

There is also a white paper (getting a little dated but still very much worth reading) that describes the potential integrations in this triangle in very clear and concrete terms (a rare achievement for this kind of exercise). It ends with “simplicity, flexibility, manageability, testability, reusability. A key combination for enterprise developers”. I am happy to grant the “flexibility” (thanks OSGi), “testability” (thanks Spring) and “reusability” (thanks SCA) claims. Not so for simplicity at this point unless you are one of the handful of people involved in all three efforts. As for the “manageability”, let’s call it “manageability potential” and remain friends.

That last part, manageability, is of course what interests me the most in this area. I mentioned this before in the context of SCA alone but the conjunction of SCA with Spring and/or OSGi only increases the potential. What happened with BPEL adoption provides a good illustration of this:

There are lots of JEE management tools and technologies out there, with different levels of impact on application performance (ideally low enough that they are suitable for production systems). The extent to which enterprise Java has been instrumented, probed and analyzed is unprecedented. These tools are often focused on the performance more than the configuration/dependency aspects of the application, partly because that’s easier to measure. And while they are very useful, they struggle with the task of relating what they measure to a business view of the application, especially in the case of composite applications with many shared components. Enter BPEL. Like SCA, BPEL wasn’t designed for manageability. It was meant for increased productivity, portability and flexibility. It was designed to support the SOA vision of service re-use and to allow more tasks to be moved from Java coding to infrastructure configuration. All this it helps with indeed. But at the same time, it also provides very useful metadata for application management. Both in terms of highlighting the application flow (through activities) and in terms of clarifying the dependencies and associated policies (through partner links). This allowed a new breed of application management tools to emerge that hungrily consumer BPEL process definitions and use them to better relate application management to the user-visible aspects of the application.

But the visibility provided by BPEL only goes so far, and soon the application management tools are back in bytecode instrumentation, heap analysis, transaction tracing, etc. Using a mix of standard mechanisms and “top secret”, “patent pending” tricks. In addition to all of their well-known benefits, SCA, OGSi and Spring also help fill that gap. They provide extra application metadata that can be used by application management tools to provide more application context to management tasks. A simple example is that SCA’s service/reference mechanism extends BPEL partner links to components not implemented with BPEL (and provides a more complete policy framework). Of course, all this metadata doesn’t just magically organize itself in an application management framework and there is a lot of work to harness its value (thus the “potential” qualifier I added to “manageability”). But SCA, OSGi and Spring can improve application management in ways similar to what BPEL does.

Here I am again, taking exciting middleware technologies and squeezing them to extract boring management value. But if you can, like me, get excited about these management aspects then you want to follow the efforts around the conjunction of these three technologies. I understand SCA, but I need to spend more time on OGSi and Spring. Maybe this post is my way of motivating myself to do it (I wish my mental processes were instrumented with better metadata so I could answer this question with more certainty - oh please shoot me now).

And while this is all exciting, part of me also wonders whether it’s not too early to risk connecting these specifications too tightly. I have seen too many “standards framework” kind of powerpoint slides that show how a bunch of under-development specifications would precisely work together to meet all the needs of the world. I may have even written one myself. If one thing is certain in that space, it’s that the failure rate is high and over-eager re-use and linkage between specifications kills. That was one of the errors of WSDM. For a contemporary version, look at this “Leveraging CMDBf” plan at Eclipse. I am very supportive of the effort to create an open-source implementation of the CMDBf specification, but mixing a bunch of other unproven and evolving specifications (in addition to CMDBf, I see WS-ResourceCatalog, SML and a “TBD” WS API which I can’t imagine will be anything other than WS-ResourceTransfer) is very risky. And of course IBM’s good old CBE. Was this HTML page auto-generated from an IBM “standards strategy” powerpoint document? But I digress…

Bonus question: what’s the best acronym to refer to OGSi+SCA+Spring. OSS? Taken (twice). SOS? Taken (and too desperate-sounding). SSO? Taken (twice). OS2? Taken. S2O? Available, as far as I can tell, but who wants a name so easily confused with the stinky and acid-rain causing sulfur dioxide (SO2)? Any suggestion? Did I hear J3EE in the back of the room?