The short answer is that no, as long as I have any say in it, Shale will not morph to be dependent on Action2. SAF2 is too heavyweight and too complexfor my tastes (see below for more about that remark), besdes the fact that it implements a lot of stuff that is redundant to what is already part of JSF (and therefore Shale) that -- from the perspective of a new application deveoper -- just complicates the picture instead of simplifying it.
Don't get me wrong ... SAF2 is a very elegant evolution of the action-oriented controller paradigm. It's the paradigm that I have a problem with. The complete longer answer will need to wait until I finish my analysis of what Don did (but thanks for addressing WW-1357 right away!) to improve the support for JSF components in SAF2. But the bottom line is that, in 2006, I have philosophical differences with action oriented frameworks (in the sense of what we see available today) as the right long term answer to designing new Java based web applications -- Struts or WebWork or whatever. It's wonderful that you are looking out for the migration use case, where people need to add a few JSF components to their existing Struts or WebWork based apps. No matter what happens, I can be comforted by the fact that people wanting to add a bit of JSF component wizardry to their existing apps will have that option. But the end result of an SAF2 + JSF based application is pretty much the same, from an architectural viewpoint, as the result of a Struts 1.x + Struts-Faces integration library + JSF based application. You end up using only part of JSF (the UI components part ... valuable, yes, but not the whole story). Worse, though, you end up with this wierd mismash of a front controller in front of a front controller (mashed teogether in the interceptor chain in the SAF2 implementation, but the same conceptually). Leading to continual decisions during the maintenance phase of a development project ... do I add a new page via action-framework navigation, or JSF navigation? Do I use the action framework's validation scheme, or JSFs? Am I forced to depend on Spring or whatever for dynamically created beans with dependency injection, or can I rely on the fact that JSF already provides a basic facility for this? Red Flags time! Indeed, one could make the same argument Don makes about consolidation, but in favor of adopting JSF as the fundantal controller architecture, and providing a full-up JSF implementation (probably based on MyFaces) that also incorporated XWork interceptors on each lifecycle phase (see SHALE-106 and SHALE-136). At least you could test such a thing for compliance with the JSF spec, and not have to hope that the folks that are utilizing some of the more critical JSF extension points are doing so in a manner that is going to be compatible with "pure JSF" component libraries and frameworks. To me, it does not make sense for a framework to say "I adopt JSF" but then have *redundant* implementations of things like validation and navigation and depdency injection and expression evaluation and .... This is fine for a migration story, but for new development it needlessly complicates the architecture of the resulting aplications. JSF already supports navigation (pluggable, if you want something completely different). Why should I be forced into SAF2 Results? JSF already supports a validation framework (easily extensible to client side validation, see Shale's feature in this respect). Why should I limit myself to what SAF2 offers? JSF has managed beans for basic dependency injection (including the abiltity to inject beans into a particular scope, which Spring is only now supporting in 2.x). Why should I go back to a single execute method (plus prepare() if you implement Preparable) as the only application events an action ever hears about, versus the four supported by Shale's ViewController? Why should I be required (or encouraged) to use Spring even if I don't need all the fancy stuff like constructor injection that Spring provides (which, by the way "works fine lasts a long time" with pure JSF already)? To say nothing of the fact that not using managed beans means you are passing on the resource injection facilities already available in Java EE 5. To say even more nothing about the future ... keep an eye on things like JSR 299 if you want to see where the "mainstream" market is going ( i.e. not necessarily what the geeks like, but where the market opportunity for consultants is going to be the best :-). Personally, I can look back with a lot of pride at the longevity of the MVC-oriented concepts that Struts 1.x brought to the web application space. Sic years in Internet time is FOREVER! But, for me, it's time to move on. I care passionately about a migration path for existing Struts-based apps, and the current SAF2 approach is acceptable for that (although it's certainly feasible to do better on "migrate to JSF' than "migrate to SAF2" for current Struts 1.x users). You won't hear any whining about the fundamentals from me of SAF2 -- although I reserve the right to comment on the details :-) But, for new developers, I prefer to think of action-oriented frameworks as "been there, done that". The understanding of O-O concepts, and the willingness to code things in configuration files (I *hope* you guys are thinking about annotations for things like Preparable :-) you need to really leverage all the cool stuff that SAF2 includes is far too limiting for my vision of what Java as a platform needs to do in the future. I want to focus on attracting a much larger audience of developers who are *not* O-O professionals, whose idea of "code reuse" is cut-n-paste, and who might actually prefer to use tools (SAF2's fundamental architecture is pretty much untoolable, even if someone were motivated to spend the effort to build tooling around it). For the O-O bigots around this mailing list, I can take comfort in the fact that the audience I'm interested in is *many times* the size of the audience that will actually appreciate the technical elegance in SAF2. Or, if you want it all in one sentence: for new developers, I would much prefer to compete with SAF2 than to cooperate with it. If that means a (hopefully amicable) divorce, then so be it. SAF2 is a much better (technical) approach to the problems that Struts 1.x targeted, but the world has moved beyond those problems. I'm no longer interested in playing on that particular playground. Craig McClanahan On 6/20/06, Don Brown <[EMAIL PROTECTED]> wrote:
As Shale and Action zero in on their first GA release, I don't think it is too late to ask the question, "Does Struts really need two frameworks?" We have been putting out the message, "two frameworks, one community", for almost a year now, but I still sense a lot of confusion and even rejection from the Struts community. The problem is for our whole history, Struts was a single framework, what you went to if you wanted to structure your web application according to Model2 principles. Our attempts to turn Struts into an umbrella project, I feel, have failed. Struts Action 2 is seen, by some, as a simple rebranding of WebWork 2, and to be honest, it really is at this stage. Struts Shale is seen as non-sequitur, milking the Struts brand name. While these opinions are most extremely expressed by our more radical members, they are also held to some degree by some very smart, sensible people [1]. From a Struts committer perspective, Wendy made a good point to me the other day saying that Struts lacks the single purpose or vision of most Open Source projects. Despite our recent attempts to find common ground, Shale and Action are still positioned as competing frameworks with no overlap. This division leads to conflicts that suck the joy out of Open Source development. Recently, Struts Action 2 unified the programming models of action-based and component-based development by allowing the developer to adopt an action-based approach for an application, yet use JSF components and abilities where needed. We have always said the desired end state would be to return Struts into a unified framework, and I think we should jump on this chance now. I propose Struts return to its roots as a unified framework through building on three libraries to make JSF and pure Servlet/JSP development easier. Namely, I propose the Struts project to be the following subprojects, each with their own release cycle: - Framework: Struts 2 - Libraries: Struts Action, Shale and Struts Tags Struts would be the single framework the world would see. It would contain support for Action-based, JSF-based, and hybrid applications. Its documentation would promote the Struts Action controller as the preferred entry point, even if only to be used for AJAX services. Its JSF library, Struts Shale, however, could be used with a regular FacesServlet. JSF components and Struts Tags would be equals when describing how to tackle the View of an application. Struts Action would be the core library driving Struts 2, replace Struts 1.x. This library would be everything now known as Struts Action 2, but without the UI components. We would aim for a solid Action-based library independent of the view, much like Action 1.x. When we talked about what an Action JSR would look like, this would be it. Struts Shale would be repositioned as a library, which I think is a better fit. A framework to me is a comprehensive, one-stop-shop solution to create an application. A library is a collection of independent features that can be used in piecemeal. Therefore, I think a library is a better definition for Shale's collection of JSF extensions. While Struts Action would definitely support Shale, it would continue to be able to be used with pure JSF applications. Struts Tags would be the WebWork UI components, a library of re-usable, stateless tags that can be used in Velocity, Freemarker, or JSP. They would include current and future AJAX tags. These tags would most likely remain tied to Struts Action 2, but not necessarily. How would this benefit Struts Action? By splitting of the tags, we can focus on the core project and get it out the door quicker. By publicizing our JSF and Shale integration, we would open our framework up to a broader audience. How would this benefit Struts Shale? Shale would also be opened up to a broader, Action-based audience and wouldn't be seen as a competitor to Struts Action. It wouldn't lose its autonomy or pure JSF support. It would gain developer support as more Action-based apps would start to use JSF and need Shale. How would this benefit Struts Tags? The tags could evolve quicker with faster releases due to less code. They would be free to add new marginal features without worrying about bloating Struts. This project would be analogous to MyFaces Tomahawk as a library of components. How would this benefit the Struts community? Finally, Struts returns to its roots as a single framework. While pieces of it may be usable outside the Action-based controller like Shale, it becomes the single place you go to solve your application development needs. The documentation would be unified and the supporting committer community in step. If you wanted the whole framework, you download Struts. If you just want one of the libraries, they are available ala carte as well. This proposed change is primarily one of message and vision, and should have minimal impact on current development activity. With the next generation of books and conferences in the works, I think it is important to develop a clear message to the Struts community and minimize any confusion. The bottom line is we want Struts to be the place to go to make web development easier, faster, with less hassles. I think this proposal provides the vision to make that happen. Don [1] http://www.oreillynet.com/onjava/blog/2006/06/isnt_rails_supposed_to_change.html --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
