Pros and Cons of Various Java Web Presentation Lay

问题:

I'm currently working on a web app that makes heavy use of JSF and IceFaces. We've had some discussions of moving to another presentation layer, and I thought I'd take the discussion out into SO and see what the experts think.

I'm curious if anyone could weigh in on the pros and cons of the various Java presentation layer technologies. If you've only worked with one, say why you love it or hate it. If you've worked with several, give your impressions of how they stack up against each other.

Our technologies under consideration are:

• IceFaces
• JSF (without IceFaces)
• GWT (Google Web Toolkit)
• Wicket
• Tapestry

And if I'm missing anything from my list, let me know.

Thanks!

回答1:

My opinions are quite heavily biased towards Wicket because I've been using it for a while after tripping over JSP mines far too many times.

Wicket PROs:

• True separation of layout and code.
• Component based which means high reusability of site elements; For example you can create prettified form with automatic labeling and CSS styles and everything and just by changing it's DAO object in the component's constructor it's completely reusable in another project.
• Excellent support for things like Ajax, Portlets and various frameworks in general directly out-of-the-box AND more importantly it doesn't rely on anything else than slf4j/log4j to work, everything's optional!

Wicket CONs:

• Development has some confusion about things in general and Wicket generics are a bit of a mess right now although they've been cleaned a lot in 1.4
• Some components (like Form.onSubmit()) require extensive subclassing or anonymous method overriding for injecting behaviour easily. This is partly due to Wicket's powerful event-based design but unfortunately it also means it's easy to make a code mess with Wicket.

Random CONs: (that is, I haven't used but these are my opionions and/or things I've heard)

• GWT is JavaScript based which sounds stupid to me. Main issue is that it reminds me too much of JSP:s and its autogenerated classes which are horrible.
• Tapestry doesn't separate markup and code properly in a manner which could be easily validated between the two which will cause problems in the future.

回答2:

I've used GWT for a couple small projects. Here are some things I like about it:

1. It's ajax by default, so I didn't have to make it do ajax, it just came along with using GWT.
2. It's got good separation of client versus server-side code.
3. I can unit-test my client code using junit
4. It lets you built crisp, snappy apps, largely because it's ajax.

Things I don't like:

1. Some things don't work as expected. For example, I've seen cases where click events didn't fire as expected, so I had to do a workaround.
2. Auto-deploy to tomcat running in eclipse sometimes just stops working, and I could never figure out why.

回答3:

The biggest question I'd ask is why are you changing presentation layer? That's a very expensive cost and I can see the benefits of one technology outweighing the others by as much as the cost to change...

回答4:

In short:

= JSF =

PROS:

• component architecture;
• many libraries & tools;
• somewhat good IDE support

CONS:

• heavy weight, both in CPU/memory and learning curve;
• when something doesn't work as expected, it's difficult to debug

= WICKET =

PROS:

• lightweight;
• sensible templating system;
• good tutorials;

CONS:

• reference documentation is not so well organized and deep as are the tutorials;
• development team had some serious difficulties, especially when becoming and incubated project. This lead to confusion on important aspects of the framework, at that time I had to switch to another framework because of this...

回答5:

What about Stripes?

回答6:

My pick would be Wicket. Have used it and is gives excellent re-usability. It has one of the most vibrant forum/mailing list. As a question and its gonna be answered in minutes. It has excellent support for AJAX. One of the usual cons attributed to Wicket is the steep learning curve. Well those were one of the old age cons which hold no value anymore now.

JSF: Better stay away from it. Another team which developed a project on JSF is now thinking to shift to Wicket after our success with it.

@Megadix: Like you said the documentation was poor in the beginning, but not any more. There is an excellent book called Wicket in Action written by the developers of Wicket. The sample code provided on the site is also a good place to start and learn

回答7:

I'd wonder if you a have a service layer that's distinct from the web client, something that the web controllers simply invoke to get their work done.

If you do, the choice of web UI technology can be decoupled from the back end. If it's exposed as a contract first web service, you can have different apps share it. As long as your clients can send and receive XML they can interact with your services. Want to switch to Flex? No worries - point it at the service and render the XML response.

回答8:

See my comparison of Wicket and Tapestry 5: Difference between Apache Tapestry and Apache Wicket.