Spring vs. Java EE

I like Java, but I've never tried diving into the Spring or Java EE world. The little I've looked at it seem daunting and complex and I'm not sure what it really gives you at the end of the day. What functionality does it provide, what are the killer features? And is all this complexity justified?

JavaEE provides a lot of the stuff programmers like me want in a way that is more or less consistent between different vendors.

Typically this includes database access, ORM, message bus access etc.

It also does so in a very integrated way so you can easily have for example a transaction that spans database modification and sending to a message bus.

I like it. I found that embracing it allowed me to simplify lots of code.

Depends on what you're trying to solve. If you need to use a database, serve or get data over HTTP, run things every hour etc. chances are you'll save time and have a more stable and performing solution by using libraries from other parties. For example Spring libraries.

Spring (and latest JEE editions with better support of DI) no more encourages spaghetti designs than does manual wiring of objects, so usually these giant balls of mud are the result of project management and design mistakes, not the failure of the tool. In fact, properly designed system that uses DI is indeed decoupled (because you can limit the number of interfaces between components) and modularized (because you can wire dependency of one module on interface with implementation in another one). Moreover, it opens the way to plugin architecture, because application context definition can serve also as plugin definition and there exists discovery mechanism (e.g. classpath:/plugins/*.xml in plain DI or Spring Boot AutoConfiguration).

I'll put my disclosure up-front: I work for Pivotal on a Cloud Foundry project. Pivotal employs many members of the Spring team. I am not speaking for either Spring or Pivotal.

Both Spring and Java EE are very featuresome because of a long period of evolution across multiple partial paradigm shifts (3-tier, CORBA, Web 1.0, App Containers, SOA, VMs, Web 2.0, Containers...).

I'm personally only familiar with Spring. And by "familiar" I mean I've learnt enough to be dangerous. But I've also learned to ask, before doing something: "Have the Spring team already solved this?"

Take, for example, retrying an operation. A slightly hacky way to achieve this is to nest try-catches. A slightly less hacky way is some sort of loop. Then we extract this functionality out. I dunno, lambdas maybe?

Or: I could use Spring-Retry[0].

That's just one example from my own experience.

It used to be that Java EE was it. And it had to be: the mega-buyers insisted that there were sufficiently rigorous standards that they could switch vendors. Every giant corporation bleeds gold to some ancient vendor and they have an immune reaction, nearly a spasm allergy, to vendor lockin[1].

Opensource tools kinda sail around this, because ... uh ... what vendor lockin? Who has you grasped, by what kind of delicate hair? Nobody. It's opensource. You can wait for community action, or engage a consultancy, or a related product company, or hire specialists, or sponsor something ... you have a wider range of options.

Oh sure, there's tech lockin, but that's true of any decision. Either you exploit the features of a platform and tie yourself to it, or you write a rubber-room abstraction layer and tie yourself to that instead, but at your expense.

In my observation as a 1st? 2nd? party, the Spring team pay close attention to the standards and support them. And, not coincidentally, many standards look -- gee, just awfully similar to something Spring had road-tested a few years prior.

I think a lot of the shade thrown in this debate is happening because of money. Pivotal backs Spring very strongly, because it helps to sell our version of Cloud Foundry (imaginatively: Pivotal Cloud Foundry).

Meanwhile, Oracle owns a lot of Java products, some inherited from Sun, as well as being the stewards of the Java EE standards process. Red Hat own a solid suite of Java EE-capable and platform products, a portfolio largely overlapping with Pivotal's, IBM's and SAP's.

In each of these cases there's a zero-ish sum-ish game underway. A company that bets on Red Hat doesn't bet on IBM. A company going all-in with Oracle (RIP your chequebook) isn't going to buy much from Pivotal.

Meanwhile, the Spring team are just writing software. I lurk some of their internal Slack channels. It's almost exclusively technical and usually very thoughtful. As a Pivot indoctrinated by Pivotal Labs, I appreciate having a very different example of how to develop high-quality software.

[0] https://github.com/spring-projects/spring-retry

[1] You will often find companies accusing each other this.