Disruptive forces don't come along all that often in the development world. They do in the IT world in general. You could easily say that cloud computing or the emergence of mobile applications have been disruptive forces, but they don't fundamentally change the way we approach the task of actually writing code and developing our apps.

In the Java ecosystem, the last major disruptive force that really changed how we developed our applications was Rod Johnson and his promotion of dependency injection. The Spring framework really did become a disruptive force in the Java world, and even when DI and AOP techniques became more and more mainstream, Rod Johnson always remained a strong personality in the Java realm.

But what will be the next, big disruptive force in the development world? Is is Scala? Scala's got a good shot at making it. It's certainly got a passionate development community behind it. But what will it take for Scala to go beyond the tipping point as the Spring framework did at some point in the last decade? Maybe TypeSafe just needs more money to make it happen?

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Disruptive forces in Java: Is Scala the new Spring framework?

So, what about Grails? Groovy seems to be in the same sweet spot as Scala and Grails offers the Spring Framework foundation plus a modular approach? Doesn't that give it an advantage over Scala?

I think (and hope...) the Java world appreciates static typing more than that. But I don't think Scala will ever be mainstream either. Based on a brief look, Ceylon looks more promising as far as the language design goes (finding the balance between difficulty and features/flexibility).

Grails is the new Spring Framework.  Scala is too different for Java developers.  Groovy is nice and gentle and makes Java developers feel good.

No and no

+1

If it happens, I reckon the next disruptive move in the Java world will be inclusion of Lambda expressions in Java 8.    It'll change the way we write code, the way APIs are done, and it will lead to plethora of new libraries/frameworks to simplify and change the way we write java code.  That is, if it is good enough and successful.  Otherwise it'll just chase people away.

Scala has got too big a type system, combined with complete lack of backwards compatibility, to ever become successful in the mainstream.  However, I reckon it'll inspire a number of smart people, just like Smalltalk influenced a small platoon of thought leaders in OO before.  Once they leave Scala behind and turn to charming average Joe developer with new ideas on how to write good code, it'll create ripples.

Scala has several nice features, but it's too complicated for average Joe programmer.