What type of webapp is the sweet spot for Scala's Lift framework? - scala

What kind of applications are the sweet spot for Scala's lift web framework.
My requirements:
Ease of development and maintainability
Ready for production purposes. i.e. good active online community, regular patches and updates for security and performance fixes etc.
Framework should survive a few years. I don't want to write a app in a framework for which no updates/patches are available after 1 year.
Has good UI templating engines
Interoperation with Java (Scala satisfies this arleady. Just mentioning here for completeness sake)
Good component oriented development.
Time required to develop should be proportion to the complexity of web application.
Should not be totally configuration based. I hate it when code gets automatically generated for me and does all sorts of magic under the hood. That is a debugging nightmare.
Amount of Lift knowledge required to develop a webapp should be proportional to the complexity of the web application. i.e I should't have to spend 10+ hours learning Lift just to develop a simple TODO application. (I have knowledge of Databases, Scala)
Does Lift satisfy these requirements?

Well, you could cruise through the Lift getting started guide in which you build an Ajax To Do app ;-)
Lift has been around for 3 1/2 years. The Google Group has nearly 2,000 people on it. There are 40 committers, of whom, 10+ make commits each month. We close between 40 and 80 tickets per month, do monthly milestone releases. Companies like FourSquare, Xerox, and Novell have hardcore apps built on Lift.

IMHO, Lift meet those requirements. Not so sure about #4, though, on the other hand, it has a good collection of back ends to interact with other services.
I think it mostly hinges on complexity. Lift does things its own way, which you may get easily, or you may not. I'd take a day to write that TODO application -- and be sure to make use of the liftweb group, as there just aren't many Lifters on Stack Overflow -- and see how that goes. I think you'll be able to form an opinion on it -- just a day.

On sweet spots: http://seventhings.liftweb.net/

i think you should post this in the lift mailing list too:
http://groups.google.com/group/liftweb

After reading seventhings.liftweb.net and skimming the first two chapters of Lift in Action, Lift's sweet spot looks to be, complex HTML page-based applications with advanced client-side functionality (like Facebook and Twitter).
Compare to single-page ajax "webapp" applications (like a calendar, or mostly anything built with ExtJS) that provide advanced client-side functionality with pure javascript and ajax middle tier services but the programming model is javascript, html is abstracted away. Compare also to traditional HTML "website" based applications like a wiki or blog -- think twitter bootstrap + jquery -- that don't need advanced client-side functionality.
single-page webapps and page-based websites i think would be made more complex than necessary with Lift unless you had an experienced & disciplined team. This probably correlates with product maturity and team size - facebook and twitter are extremely large applications with hundreds of interacting teams and strong engineering leadership.
a small team of people still exploring and forming opinions on how various apps should be structured is likely, i think, to be mislead by Lift into more complex solutions when perhaps all they needed was straightforward HTML templates and simple ajax endpoints.

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Is GWT still an option for a large business application [closed]

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My company is planning on developing a brand new web front-end application.
Some background:
It must "sizzle" i.e. a nice marketable look and feel.
Our development team has no Java experience, with limited experience in Silverlight, Javascript, JQuery or CSS.
Time to market is a factor.
We need to stream large amounts of data from an Oracle database.
It must support 500 - 1000 concurrent users
It will be hosted internally behind a firewall.
We need mapping (geo-spatial) capabilities.
Someone has recommended using GWT instead of Silverlight or Traditional technologies(Javascript, jquery, CSS etc.).
I am not sure if this is the right way to go? A lot of the GWT news is from 2007/2008. It makes me think that this technology is old and maybe dying.
If you had a choice would you choose GWT?
unfortunately two of your statements are mutually exclusive in this context:
Our development team has no Java experience
Time to market is a factor
I'm a Java programmer who has picked up GWT over the last year or so. It's immensely effective being able to write direct to the browser using a compiled language & mature development tools. I can fly through web-development faster than ever before (using ASP, JSP, ExtJS ...).
But, as the other commenters have said: if you've no Java experience you're going to find it a real challenge picking up both technologies (Java & GWT) in a short time. If you do manage to make it to market in a reasonable time I could only imagine the code base would be in very poor condition (since you'd be learning as you go) - which would be a very poor foundation for your organisation's shiny new venture.
There again, you don't have a 'lot' of skills in the other related skills you listed either.
I suspect there's a more effective solution. As some wise old goat project manager said:
I have three variables to delivering your project: time, cost and quality. Pick any two
In your situation, if the organisation wants a quality product in a short time, it's the cost factor that must compensate - your organisation should buy in some interim GWT expertise to give you a sound software architecture and to mentor your team for the next few months. After that you'll be ready to take the reigns, inheriting a quality codebase by 'standing on the shoulders of giants'.
As others have said, GWT definitely is not a dying project. Quite the contrary actually as there are now more than 20 regular contributors from within Google (versus a semi-dozen back in 2008). Wave (despite being discontinued as a Google service, it's still alive as an Apache Foundation project), Orkut, AdWords, Google Moderator and the new (still beta) Google Groups are made with GWT; and parts of Google Buzz and a few other projects at Google are built with it too.
Now as to your choice:
Silverlight is a dying technology. Microsoft made it clear that it now invests in "HTML5": http://www.zdnet.com/blog/microsoft/microsoft-our-strategy-with-silverlight-has-shifted/7834
GWT is mostly a client-side toolkit, but it comes with "high productivity" tools for client-server communications (GWT-RPC and RequestFactory for end-to-end protocols, AutoBeans for easy JSON serialization). With UiBinder, you can easily put to use your web designer skills.
if you're comfortable with JS, then go for it, but then you'd have to choose the "right toolkit" (jQuery? Google Closure?). Otherwise (which seems to be the case), it really depends how much "ajaxy" you need/want to be. I'm a strong believer in "one-page apps", but YMMV, or you can have specific constraints that rule it out. In any case, you'd have to choose a server-side technology.
So, depending on your needs/wants and skills, I'd choose GWT or "some JS toolkit". In any case, you'll have full control over the look and feel (unless you choose one of the bloated players: ExtJS/ExtGWT, SmartGWT or similar; you'll probably have a shorter time-to-market with these, but you'll pay it later, in terms of performance, integration with other toolkits, and look-and-feel).
In the light of what you're saying about your skills, I would definitely recommend GWT (despite your lack of experience with Java); because lack of experience with JavaScript is far worse than lack of experience with Java (you're talking about a "large application", so it's really important to start building things right and/or have tools to help refactoring, which you'll have with Java).
#ianmayo replied while I was writing the above, and I can only second what he said!
GWT is definitely not old or dying! A lot of Google's own applications are developed using GWT. You can download the GBST case study and learn how the global financial company uses GWT to improve productivity and create a rich user experience. You have to know that when you use GWT you automatically use javascript, html, etc. You create a your gwt application in java, but when you compile it gwt creates a folder with html files, javascript code, css, etc...
I definitely recommend it!
In order not to mislead readers with above seemingly unanimous answers, keep objective view in respected stackoverflow, following review expressed exact experiences I had with using GWT. Whether GWT is dying depends on how many new apps will adopt it,Google trend can tell (gwt trend).
Excerpt from https://softwareengineering.stackexchange.com/questions/38441/when-not-to-use-google-web-toolkit
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I am both good and bad to answer this question - good, in that I've actually used it before, and bad, in that I was quite experienced with HTML/CSS/JavaScript prior to working with GWT. This left me maddened by using GWT in a way that other Java developers who don't really know DHTML may not have been.
GWT does what it says - it abstracts JavaScript and to some degree HTML into Java. To many developers, this sounds brilliant. However, we know, as Jeff Atwood puts it, all abstractions are failed abstractions (worth a read if considering GWT). With GWT, this specifically introduces the following problems:
Using HTML in GWT sucks.
As I said it, to some degree, even abstracts away HTML. It sounds good to a Java developer. But it's not. HTML is a document markup format. If you wanted to create Java objects to define a document, you would not use document markup elements. It is maddeningly verbose. It is also not controlled enough. In HTML there is essentially one way to write
<p>Hello how are <b>you</b>?</p>
In GWT, you have 3 child nodes (text, B, text) attached to a P node. You can either create the P first, or create the child nodes first. One of the child nodes might be the return result of a function. After a few months of development with many developers, trying to decipher what your HTML document looks like by tracing your GWT code is a headache-inducing process.
In the end, the team decided that maybe using HTMLPanel for all HTML was the right way to go. Now, you've lost many of GWT's advantages of having elements readily available to Java code to bind easily for data.
Using CSS in GWT sucks.
By attachment to HTML abstraction, this means that the way you have to use CSS is also different. It might have improved since I last used GWT (about 9 months ago), but at the time, CSS support was a mess. Because of the way GWT makes you create HTML, you often have levels of nodes that you didn't know were injected (any CSS dev knows how this can dramatically affect rendering). There were too many ways to embed or link CSS, resulting in a confusing mess of namespaces. On top of that you had the sprite support, which again sounds nice, but actually mutated your CSS and we had problems with it writing properties which we then had to explicitly overwrite later, or in some cases, thwarted our attempts to match our hand-coded CSS and having to just redesign it in ways that GWT didn't screw it up.
Union of problems, intersection of benefits
Any languages is going to have it's own set of problems and benefits. Whether you use it is a weighted formula based on those. When you have an abstraction, what you get is a union of all the problems, and an intersection of the benefits. JavaScript has it's problems, and is commonly derided among server-side engineers, but it also has quite a few features that are helpful for rapid web development. Think closures, syntax shorthand, ad-hoc objects, all of the stuff done by Jquery (like DOM querying by CSS selector). Now forget about using it in GWT!
Separation of concerns
We all know that as the size of a project grows, having good separation of concerns is critical. One of the most important is the separation between display and processing. GWT made this really hard. Probably not impossible, but the team I was on never came up with a good solution, and even when we thought we had, we always had one leaking into the other.
Desktop != Web
As #Berin Loritsch posted in the comments, the model or mindset GWT is built for is living applications, where a program has a living display tightly coupled with a processing engine. This sounds good because that's what so many feel the web is lacking. But there are two problems: A) The web is built on HTTP and this is inherently different. As I mentioned above, the technologies built on HTTP - HTML, CSS, even resource-loading and caching (images, etc.), have been built for that platform. B) Java developers who have been working on the web do not easily switch to this desktop-application mindset. Architecture in this world is an entirely different discipline. Flex developers would probably be more suited to GWT than Java web developers.
In conclusion...
GWT is capable of producing quick-and-dirty AJAX applications quite easily using just Java. If quick-and-dirty doesn't sound like what you want, don't use it. The company I was working for was a company that cared a lot about the end product, and it's sense of polish, both visual and interactive, to the user. For us front-end developers, this meant that we needed to control HTML, CSS, and JavaScript in ways that made using GWT like trying to play the piano with boxing gloves on
First of all , GWT is not dying technology, its usage increases, and its latest version is 2.2. I am using GWT for 2 years, since version 1.6. Its improvements since them is quite amazing.
Since GWT is client side technology, it does have only positive effects of your application scaliblity feature. Because server side web technologies such as jsf, struts, wicket are server resource consumers, but gwt does not need any server resource to render user interface..
But there is problem for your team. Because your team has no java experience, it would be quite difficult to adapt yourself two new technologies java and gwt.. If you have time to learn , I would strongly suggest GWT.
It takes approx 1 year to become proficient in GWT. Using GWT pays off if you develop an application as sophisticated as MicrosoftOffice or PhotoShop. It makes no sense to use GWT for small and relatively simple apps, IMHO. GWT is a time killing framework indeed, and you have to have very strong reasons to use it. I think that 99% of web apps don't need GWT.
GWT is not dying framework, but time killing framework. It has security issue. You can do easily CSRF(Cross site request forgery) request to the GWT applications. Also Java and Javascript are totally different languages, you can't translate easily. For your productivity avoid GWT.

Cafeteria Management System as a project. What should I use?

This is a part of my course project.
Basically, there are vendors which provide food and at peak hours the queue gets so large that people have to wait long for their order.
Our project is like an online site which will enable users to order food. After ordering the food, the user will get an info as to where does he lie in the queue. This way students can order from their hostel rooms without actually going to the vendor and getting their time wasted by waiting in the line. As soon as the user orders the food, vendor gets notified of the project so that he can start preparing the food.
I am completely new to web development so I am not sure what to use. This project will also work as an exercise to learn about web development.
I have heard about Drupal & Joomla CMS. Also, Django framework is also there and I am actually confused as to what technology to use.
I am also confused as to what is the difference between a framework and a CMS? How do they differ and which one will suit me.
So, how do I go about developing the
application?
A framework is a basic application without any concrete business logic. It contains basic structure and sometimes basic features (like database connectivity and other standard libraries). You have to write your code yourself.
A CMS is a content management system. It is essentially a complete website but without the content. it provides tools to write content (web pages). The most popular ones (like Joomla) come with a bunch of templates too that you can download to give your site any look you want.
A CMS probably doesn't have enough features to provide you with this logic. You will probably need to do some programming to get this done. It may still be useful to use a CMS, though. Lots of them support various plugins that allow you to add these kind of features and still allow you to easily edit regular pages.
Frameworks are libraries turned on their heads. You plug a library into your code; a framework turns this around by abstracting a particular problem in such a way that you plug your code into it to solve a problem. It's the Hollywood principle: "Don't call us; we'll call you."
People who write frameworks have deep knowledge of a particular problem domain. They usually represent the distillation of several attempts to solve a problem, with best practices, clear abstractions, and good plug-in points made clear from long experience.
Django is a Python framework for web applications that have a browser front end and relational databases for persistence.
That's one example of a framework.
A CMS (Content Management System) allows users to dynamically add and manage content in a web application. I think they solve slightly different problems from Django, because it is specialized to the problem of content management.
I'd recommend starting your queuing problem without a front end at all - just text. Concentrate on the subtleties of queuing. Get that right with your object model and then expose a user interface to display it to users.
CMS is a 'content management system'. If provides modules that you can plug in. The end effect is it sets up a website for you, and you have admin pages where you can enter content. For special stuff, you use plugins. If you have to, you can write your own plugins.
A development framework is just a stack of technologies you can use to develop an application. So for example, the Grails framework uses Hibernate(persistence) and Spring(dependency injection and other stuff) under the covers -- it is providing and using existing tools (which are themselves frameworks) which you will in turn use to build the application.
With a framework, you basically start with a bunch of tools in your toolbox, but little or no parts of a running web app out of the box. You have to develop the functionality with the tools. With a CMS system, it's like they have implemented something for you, but it is really generic and you will have to tailor it to your needs.

Zend Framework - Ruby on Rails has a screencast showing how to code a blog in 15 minutes. Does ZF have a similar screencast?

Ruby on Rails has a screencast presentation they use to promote their framework that shows how to code a basic weblog system in 15 minutes with RoR. Does the Zend PHP Framework have a similar screencast/presentation/whatever demonstrating something similar? It doesn't have to be a blog specifically, but I would definitely like to find a presentation that shows some rapid application development using ZF.
Where I'm coming from: I have been programming on and off for years now. I started out with QBASIC waaaaay back in the day making little programs (text adventure games, screensavers, simple little things). I then moved to C++ but never really did anything too impressive with it. Since then (probably 5 years or so now) I have started to use C# for my desktop development and PHP for my web development. I've made some pretty cool tools here and there, but am certainly not a professional programmer by any stretch of the term as it has always simply been a hobby of mine.
Right now I have two major web applications that I will start work on shortly. (Like tomorrow, or later tonight ideally.. :) ) Both will be database-driven apps that will require user registration, the ability to manipulate data that is specific to their account (their posts, listings, user account details, etc), amongst other things.
Currently I am evaluating different frameworks to help me develop these web apps more quickly. I've been looking at, and have heard good things about Ruby on Rails. Hulu and YellowPages.com using it is an obvious endorsement - Of course, I have heard about the scalability issues that it potentially has; but that shouldn't be an issue with what I am working on. I don't expect millions of users per day for either project.
I am also seriously looking at the Zend Framework for my needs because I already have some experience with PHP. Ideally I would like to find a ZF screencast that shows an app being written quickly so that I have a roughly equal comparison between the two options I am exploring and can see first-hand how things get done in both.
That said - I am not opposed to considering frameworks other than RoR or ZF. The only research I've done on the subject has been over the past couple of days so I am quite certain that there are other excellent options out there that I've not even looked at - or heard of. Of course, it'd be awesome if there is a rapid app dev presentation that I can watch for whatever else is suggested.
So - Suggestions? Links to good screencasts that show rapid application development in other frameworks? Are there other PHP frameworks that I should be considering? (Ones that are easy to deploy would be ideal, so I don't have to purchase a dedicated server that I have full control over. I'd like to keep my hosting costs down assuming that it's reasonable)
Thanks in advance!
-Sootah
You can checkout ZendCasts.com
However, when deciding between ZF and RoR, you should be aware that they are very different from each other. RoR is a full stack with integrated ORM built on AR and a rather rigid structure. It's powerful and there is lots of magic inside and I'd say it's RAD capabilities are above ZF due to rake being more powerful than Zend_Tool
ZF, on the other hand, is first and foremost a loosely coupled component library with a use-at-will architecture for maximum flexibility. You can use it's components together, but you don't have to. While it does feature convention over configuration, ZF doesn't take you by the hand too much. It expects you know how to walk. Also ZF has no full fledged ORM and no AR, but you can very much integrate Doctrine or Propel or whatever library you like to use.
You often hear folks new to ZF complain about it is hard to get into it, simply because they expect ZF to work like RoR or Symfony or Cake, e.g. a full stack framework
EDIT:
Cake aims to be a port of RoR to PHP. It is built around ActiveRecord. Like CI < v2, it is backwards compatible with PHP4, which means it doesn't fully utilize the OOP capabilities you get in PHP5. I'd say both are easier to get in than ZF though.
This is a common question on SO.
I posted some valuable links in my response to this post
If you Google for such tutorials, look for Zend Application or Zend Tool, not ZF.
The difference between the other frameworks and Zend Framework is that Zend Framework is rather a general purpose framework, not application framework (not only for MVC, HTTP). E.g. Google uses ZF to provide access to their services.
You may easily use Symfony or CodeIgnitier with Zend Framework together.
BTW, To be precise, tutorials you ask are not blogs, but just a simple CRUD controllers. You may use Wordpress to create blog in 15 minutes, (then customize it) but not a PHP Framework.

Should web based applications follow web standards?

By day, I am a front-end web developer but in my off time I dabble with other languages such as C, Objective-C, Python, etc. When I first got into web development the idea of web applications was just getting started.
Since then two amazing frameworks have appeared, SproutIt's SproutCore and 280 North's Cappuccino (+Objective-J). SproutCore is being used by Apple for it's MobileMe application and 280 North released 280 Slides. Both of these applications are amazing and they are a testament to what is possible on the web. So the momentum is shifting. Web applications starting to look and act like desktop applications.
So my question is this: should web based applications follow web standards, separation of markup (content), presentation (design), and behavior (functionality) or no?
I am not sure about SproutCore since I have not look at the source code, but I know that if you go to 280slides.com and turn off the JavaScript everything basically disappears. You are left with some meaningless words.
Let me clarify, I understand that web based applications such as 280 Slides is meant to have JavaScript on and not meant to be functional without it but in my day job my main focus is writing clean markup, separating content, presentation, and behavior so that our site and applications can be used by as many people as possible.
It seems like the other people who have answered so far have no idea what you're talking about.
Like me, you've had it pounded into your head to make your web applications as accessible as possible. That is, they should work without scripting and without stylesheets. JavaScript and CSS should only be used to enhance the experience. They should not be required.
SproutCore and Cappuccino are frameworks for front-end development that require the user to have both JavaScript and CSS enabled. Your question is around how we reconcile this with the dogma of the day.
Unfortunately, I don't have a clear-cut answer. I like the fact that SproutCore and Cappuccino (and probably others) are testing the limits of what's possible within a web browser. I also believe firmly that information and services provided on the web should be available to as many people as possible, given the limitations of the technology.
How you approach your solutions needs to be based on a deep knowledge of your user-base. If you're working on an iPhone app, you don't need to worry about traditional web accessibility because the experience is intensely visual. If you're building a web application for a general audience, these new frameworks are probably a poor choice (if you value the widest possible access to your information and services).
Over time, screen reader software is likely to get better at interpreting JavaScript-heavy interfaces, so perhaps this issue will fade. Thing is, something else is likely to "sprout" up in its place.
Javascript is a Web standard — certainly more so than, say, Flash, which was previously (and still often is) used for rich Web applications. In this regard, SproutCore and Cappuccino are giant improvements in my book.
The question here really seems to be how important accessibility is. And that is largely a personal decision based, as Andrew said, on knowing your users. For some apps, accessibility really doesn't make that much sense — 280 Slides is a good example of this. It's a graphic design app that's largely about visual behaviors. It doesn't make very much sense for it to degrade to plaintext. (At least, a text-based app meant to accomplish what 280 Slides does would be really be a completely different thing.)
Yes. It will be difficult at first, but once the codebase matures you will be thankful you followed those rigorous standards.
Edit: An added benefit will be portability to many web-based platform via CSS profiles and whatnot.
The MVC model can be applied just as easily to desktop applications as it can to web based applications. I don't see much reason to distinguish between the two, especially since the line is more blurred in the case of web applications.
I don't know about these particular frameworks, but a lot of web frameworks these days are structured around the MVC model, such as ASP MVC, CakePHP, Ruby on Rails, etc.
Separate as much as you can and it will pay out in the end. When things get complicated and hairy :)
I think they should. Following that type of MVC design allows for changes to be more easily implemented, provides good separation of concern, and is generally easier to understand for newcomers to a project.

productivity superstar frameworks/tools for side gigs

If you were going to start building web sites as a consulting business on the side -- keeping your day job -- and you also had a toddler and a wife, what frameworks/tools would you pick to save you typing?
Any language.
I'm looking for a productivity superstar stack that won't tie my hands too much when I have to update the site 6 months later, or "evolve" the data model once in production.
It needs to allow me to say "yes" to the client: community features, CMS, security, moderation, AJAX, ...
I would suggest Django. Super simple to get something up and running really quick. You are using Python which has a large library to go with it. For me Ruby on Rails would be a close second.
I'd probably look at DotNetNuke. Its easy to set up (a lot of hosts will do it for you) and easy to use and put together a custom site that business's will be able to maintain in the future.
Its fairly easy to create custom modules that are specific to a business and hundreds of modules for sale (or free) that can be integrated into DNN for special uses.
Take a look at Microsoft's Sharepoint server if you'd like a pre-made framework with many options for plugging in your own code. Sharepoint is kind of a world unto itself but it is a very powerful environment.
Update: I'm surprised to have been voted down on this one. Keep in mind that the questioner specifically requested frameworks that included a CMS. Sharepoint meets this criteria - unlike straight .NET or other web development frameworks.
If you are going to vote the entry down, I think you owe it to the person who asked the question to explain why you don't think he should not even explore it as an option. You could be right - collective wisdom is what voting on SO is all about. But without an explanation, we don't know why you think you are right.
My answers are going to revolve around the .NET stack.
Use Master pages and CSS templates. This makes it so much easier to pop in a new look and feel for your customer.
For sure I'd include the Dynamic Data framework in the .NET world.
Hosting might become an issue for your customer. Questions around managing email addresses, procedures on how to quickly update the website to include the new contact phone number (different for each customer, I'd assume) Consider getting a reseller account on your favorite webhost, and dole out webhosting accounts as appropriate. There are lots of issues around this point. It may turn out to be a nice source of recurring revenue.
Build yourself a few patterns including a database wrapper which would handle all your data calls (i.e. a dll which wraps all your data calls, sets up your ADO.NET objects, runs your sproc calls, and picks up the connstring from app.config or something similar.)
This goes a long way to maintainability as well.
I would recomend going with anything MVC in a language you can undertand! Theres a couple of CMS's in python, php and ruby using that design and well... that allows you to be ready for combat for Ajax and expanding anything very fast.
This is definitely not a question that can be answered.
I prefer asp.net webforms because I think it allows for extremely rapid web app development, but I am sure you will receive recommendations for:
asp.net mvc
Ruby on Rails
PHP and some framework
Python and some framework such as Django
I believe PHP has the most pre-built apps that you can use, though asp.net also has the things you are looking for.
All of these platforms and frameworks can do what you want.
Choose between Rails and Django. They both have different strengths. I like Rails better in general, but Django's admin interface can save you a lot of time when you need it.
There's another factor to take into consideration here: what are you the most familiar with? I believe that some studies have found upwards of a 30% loss of productivity when trying to learn a new language/framework.
Sometimes, there's nothing wrong with just sticking to what you know. But if you're interested in what languages/frameworks to learn, I'll refer you to the other posts because the above was the only thing I really have to add.
I recommend looking into Grails. It uses Groovy which is similiar to Java (so if you know this already you're good to go). Groovy runs on the JVM so you can still use all the great libraries already available for Java. Yet, since it's a dynamic language with a lot of the similar bells and whistles like Ruby you can use closures and that kind of neat stuff when you need/want to. And you're not slowed down by Java's traditonal slow compile-deploy-test development cycle.
Grails is already setup with Hibernate and Spring. You can create CRUD application in practically no-time (pretty much like Rails applications), and at the same time drill down and be able to control every little details since it's built on such proven and well-supported technologies. In addition there's literally hundreds of plugins available that helps you easily set up things like mailing lists, security, AJAX components and so on.
Otherwise, if you want to set up a community site and don't want to code a single line you could always check out ning.com.