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We plan to use smart GWT, GWT and related frameworks for the client side rich interface and Spring MVC which returns JSON data on the server side.

As part of the investigation to see if it fits our requirement, the following questions need some answers :

  1. Building a GWT application from scratch without using any frameworks will need considerable amount of effort to follow the standard MVP pattern. But this is more flexible and unit testable, though time consuming. GWT best practise suggests using MVP design pattern for building larger applications.

SmartGWT has its own approach, where you use a widget, introduce a datasource into it and you are done. Yet to identify the best practise around building such smart GWT components in a modularised (or MVP) fashion. Any suggestions

  1. Using framework GWT-platform and SmartGWT could be an option to try MVP architecture as mentioned here. Any suggestions?

  2. Validation/message/exceptions display and other generic feature support of smart GWT is yet to be investigated.

  3. Client server architecture: Having Spring MVC + Spring core on the server side and GWT + Smart GWT on the client side could be a good stack of open source technologies, but given that GWT by default uses RPC for client server interaction, usage of these needs to be better evaluated. (esp. authentication/session handling/security etc). Any suggestions?

Thanks

MountainRock
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  • I built my app using SmartGwt and MVP. There is an answer I wrote in another thread exlaining how I did it, that might be of interest to you. http://stackoverflow.com/questions/2832779/is-there-a-recommended-way-to-use-the-observer-pattern-in-mvp-using-gwt/2832919#2832919 – Mia Clarke Mar 06 '11 at 13:30

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I nerver used SmartGWT or any other rich libraries. My opinions may be biased, but I really think that Gwt components are easy to customize and lightweight. That's something I never felt coming from SmartGwt are any other librairie of that type.

That being said, here's my answer to two of your concern:

Using framework GWT-platform and SmartGWT could be an option to try MVP architecture as mentioned here. Any suggestions?

Well, to stay MVP like in that aspect, just set the datasource from the presenter. In your view, the SmartGWT widget should be "passive" and wait for configuration coming from the presenter.

Advantage: You don't have to unit test the view, since SmartGWT widgets should already be well tested. You only have to test the presenter where you actually call the view to configure that widget and verify if you call it correctly.

Client server architecture: Having Spring MVC + Spring core on the server side and GWT + Smart GWT on the client side could be a good stack of open source technologies, but given that GWT by default uses RPC for client server interaction, usage of these needs to be better evaluated. (esp. authentication/session handling/security etc). Any suggestions?

RPC is an option, not the default communication. There's two other type of communication (and even more if you try experimental feature like DeRPC): RequestBuilder and RequestFactory.

RequestBuilder could be use to HTTP GET with JSON Response. Can't help you for the smart GWT approach.

Here's a user of Gwt-Platform that use Smart GWT, read his blog, it should enlighten you: http://uptick.com.au/blog

At the time of writing this answer, the blog was down, but it should come back soon.

Christian Goudreau
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  • Thanks Christian for sharing. We are using Spring MVC and GWT +Smart GWT widgets with RestDatasource. Have chosen JSON request/response data format. So far so good. But initial impression is that the Smart GWT lacks standards and hard to customise. – MountainRock Mar 15 '11 at 23:32
  • Based on your other comments you are overcomplicating your applications for reason that have nothing to with SmartGWT. Name an actual customization scenario (in a new thread here or on the forums at forums.smartclient.com) and we will show code to achieve it that is simple and straightforward. – Charles Kendrick Apr 21 '11 at 18:12
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I am currently working on a Smart GWT / GWT application.

My opinion of Smart GWT currently is that it does save a lot of time, and it provides some good-looking, useful widgets. That said, because it's a wrapper around a JavaScript library it does have some caveats, particularly when debugging. Often it makes it much more difficult to track down an error than it would be using plain GWT (or GWT with a library that wasn't a JavaScript wrapper).

To try and comment on your questions:

  1. I haven't found the Smart GWT libraries to be a problem in this respect. It's probably different to the GWT recommended way but it doesn't mean you suddenly have to abandon all best practices.

  2. Can't really comment on this - haven't found the validation / message / exception libraries to be an issue

  3. We use JAX-RS for the client / server communication, which Smart GWT supports natively and is pretty easy to implement. It's possibly a bit easier to debug than GWT RPC because it uses an XML format. We just use Spring Security for the security and, again, no issues there.

I think the main thing for us that would make me think twice about using Smart GWT again is the customisability: when you use their forms, for example, you can't do very much with them in terms of layout. Smart GWT has its own way of doing things, and you're pretty much locked into that way unless you want to write your own components (which isn't ideal because Smart GWT don't recommend mixing Smart GWT and plain GWT components).

If you're happy to write an application which uses the Smart GWT library and doesn't require much customisation it would be fine.

  • Thanks, We have a Scenario: ListGrid -->select record --> send request to server to fetch details of the record --> show details of this fetched record as readonly Question: 1. What is the best approach to send HTTP GET request and rendering the JSON response in a Smart GWT component. 2. We considered using DetailsViewer and Dynamic form. Though DetailsViewer.setData(...) works when we pass the current selected ListGrid record, we want to get more details that is not held in the ListGrid row. Any help would be much appreciated – MountainRock Feb 28 '11 at 09:53
  • be sure to look at the FormLayout docs and at CanvasItem. We don't have anyone else claiming there are layout limitations. @MountainRock unless you have, say, 30+ more fields in the DetailViewer than in the grid, you should just load the full record into the grid and use component-specific fields to display limited fields in the grid (see QuickStart Guide Data Binding chapter). This avoids an extra server trip. If you have 30+ extra fields, you can call DataSource.fetchData() to fetch the complete record by primary key for use with the DetailViewer. – Charles Kendrick Feb 28 '11 at 19:17
  • @Charles Thanks. Had to abandon DetailViewer as it doesn't work with data source. Looks like its tightly coupled with ListGrid to render cached record. Ended up using DynamicForm -> RequestBuilder and parsing the response. It works well now. But having issues with Looping list grid when we try to implement server side pagination. Initial impression is Smart GWT hard to customise. Business requirements are ever changing and with such rigid widgets, its quite annoying. – MountainRock Mar 15 '11 at 23:37
  • DetailViewer works fine directly with DataSource and there is no tight coupling whatsoever to ListGrid, many samples show this. If you are using RequestBuilder and doing parsing you are radically overcomplicating your application. Instead of posting absurd commentary on SmartGWT here, try posting to the forums (forums.smartclient.com). There are many community members who will happily correct your code if your post is both complete and polite. – Charles Kendrick Apr 21 '11 at 18:10
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You should first consider your goals in using MVP.

If you look over the SmartGWT samples, you'll find they already have clear and minimal code. You can't simplify or clarify any of the samples by introducing MVP, you can only add additional code and complexity.

So you should have a very specific and concrete, very compelling reason why you want to use MVP and introduce extra code: a particular design goal that cannot be met in a simpler way by using SmartGWT normally.

It's very hard to find a valid goal of this kind, because SmartGWT is very flexible and already supports testing via Selenium, and even has Selenium IDE extensions and support for Selenium RC.

A possible example of a valid reason to pursue MVP might be having two completely separate view implementations, one in SmartGWT and a simplified one in plain GWT. I know, it's not a very good example and it's hard to imagine anyone needing to do this, but that's because we have yet to have any developer come along and articulate a reason to use MVP with SmartGWT other than very vague notions of flexibility.

If you're going to take on the task of using MVP I think you should understand the situation well enough to say something like "we need to do X, and if we use SmartGWT normally that will take 6 months, if we add MVP, it will take 3". To my knowledge, no one has ever identified such a scenario.

Charles Kendrick
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