UPDATE 1: Flash Builder 4, BlazeDS 4, and Spring 1.0.3 have all been release so you no longer have to use beta or nightly builds of these products. Use the production versions!
Last week I posted a screencast that walks through the basics of connecting a Flex 4 application to a Java / Spring back-end with the new Data Wizards in Flash Builder 4. Here is a new video that extends beyond just simple RPC method calls and adds Hibernate for persistence. Let me know what you think.
67 Comments
Thanks James for the screen-cast, cool stuff!, I like the data binding form wizard, one thing less in my wishlist, now if I could only encourage Adobe to have flash builder 4 work on linux :( , ya there are some tweaks but not quite there yet, what’s the outcome from the survey they run last month? (I participated :)
Cheers, and thanks again for the post.
Thanks Martin for doing the survey. Still no word on FB for Linux support. Sorry.
Hi,
Thanks for these two screencasts. Quite informative.
Any chance of perhaps doing something that demonstrates the use of role-based security?
Thanks
Hi Raihaan,
That would be cool. I’ll add it to my list of screencasts I want to create!
-James
+1 for a screencast with basic security. It’s the only thing I miss to really take Flex 4 for a ride on my new project.
James, thank you very much for these nice screencast. I will try to mavenize it.
+1 for security screencast.
-Ignacio
FYI, I created a Grails plugin based on your screencasts: http://grails.org/plugin/blazeds
@Sébastien That’s awesome! Thanks for posting that!
Is the source available so I don’t have to type all the config files again?
Thanks, great screencast!
Hi Martin,
Most of the configuration should be here:
http://www.jamesward.com/downloads/springFlex-server.zip
Thanks James for the cast. Just wondering if the limitations we have always had with flex-hibernate lazy loading objects have been eliminated. These examples are great and they prove the concept but it would great to have a real world example with lazy loading integrated with the flex front end. Is there any such example today?
Thanks again.
Hi salim,
You could extend the regular code generators to support lazy loading. By default lazy loading is not addressed. Everything needs to be eager. Hopefully some open source projects will crop up that deal with this.
-James
You should check out something called dpHibernate on Google Code. I don’t know if it works because I personnally prefer to use DTO’s anyway. But it might be what you are looking for.
I am sorry, it is a really nice screencast for a cool product. But I had to stop watching because of the bad practices that you are showing in the video on Spring and a layered architecture. Just a couple of comments
1) context:component-scan automatically includes context:annotation-config
2) Services should not access the database directly, so injecting or writing queries in a service class is tightly coupling your code. (Yes it is a simple example, but people will take that as the way they should go)
3) Since you created this in 2010, HibernateTemplate is no longer beneficial. You get all the benefits just injecting the sessionFactory into your Repository (again not Services), and then called getCurrentSession to get access to the Session object.
That is about as far as I could watch.
Now it looks like you had to do a lot of configuration to set things up. In another video I saw from a while ago, you only needed Springs DispatcherServlet in the web.xml and you also didn’t have to declare all the services to access them from a Flex Widget. Has this changed since then, or do we have to do it the long way like in your video? I hope it is much easier than that.
Thanks, and please excuse my “meanness” I don’t mean to be mean, and I would love to see more of your screencasts.
Mark
One thing about the lazy loading with Hibernate.
When developing using Hibernate, fetching should be use case dependent. You map everything as lazy loading, and based on the use case, you set the query you want to run to eager fetch everything you need for the page. Nothing more, nothing less.
If you had a fix on the client side to leave the Session open, you are probably going to be degrading performance because of the subsequent calls back to the server to load the next bits of data that has been lazy loaded. If you have eager fetched in the query, then the client side would already have all the data that it needed and not need the extra remote calls. So while, the up front query might be slightly slower, the speed you gain from less server side calls would outweight the gain you got from lazy loading.
LazyLoadingException is the most common exception in Hibernate, especially when you don’t consider the request and what fetching strategy is being used. While, it is simple to keep it all use case driven, it is a good example of why Hibernate has a really big learning curve. It is much more than just the mapping that is necessary to understand to use Hibernate effectively.
Mark
Wow, three comments in a row.
OK, I see why you had more configuration. Your video is just hooking Flex to Spring, but not using the latest Spring Integration with BlazeDS. In which you only need to have the Spring Dispatcher Servlet in your web.xml, etc. So I apologize for last paragraph in my first comment. I mean I apologize for it all, as I am not trying to be negative, just wanted to make sure it is using best practices so that everyone adopts this way of integrating Flex, BlazeDS, and Spring.
Mark
OK, ignore my lazy loading comment too. I see now that the problem is even if you get just the data you need for the UI, it might include associations that aren’t needed for the UI, and that Flex will traverse the entire object graph, including those that aren’t needed for the UI in that Use Case.
Thanks
Mark
Hello James Ward， Thanks for your article. I have successfully deploy a flex+spring+blazeds project., and it can work normally, but when I refresh the Data/Service view in flash builder. I catch a error that the service can’t find in the configure file. Yes it can’t find from the services-config.xml because of we useing annotation and I have to delete the service from the Data/service view and so can recompile project. Do you meet the problem? how to resolve it?
Hi yuanqixun,
That seems like a bug. Can you file it: http://bugs.adobe.com/
Thanks.
-James
Hi Mark,
Thanks for you feedback! This is really helpful. The lazy loading thing is a challenge to work around. Here is an article that walks through a strategy for dealing with that:
http://ria.dzone.com/articles/flex-hibernate-integration
As far as the HibernateTemplate, can you point me to an example that shows the right way to do it?
The extra config in the web.xml is needed for FB to connect to BlazeDS and query it’s services. I don’t think the latest Spring BlazeDS Integration does that for you. Correct me if I’m wrong.
Thanks again for your feedback.
-James
It is very good stuff about flex, hibernate and spring i have ever seen. I have tried to run this stuff, but i could’nt. It would be very nice if this stuff is published as a full tutorial.
Thanks again for another great guide. Only thing that was different for me was the generated code. I got services:Foo instead of foo:foo like yours. Hence, I had to change a few things to get it to work:
Hello James,
I got your guide almost working , so if I test operation it is fine, however running the application on the browser gives me the following error, any thoughts why this is happening:
“Detected duplicate HTTP-based FlexSessions, generally due to the remote host disabling session cookies. Session cookies must be enabled to manage the client connection correctly.
null”
-sam
@Sam I haven’t seen that before. But it looks like others have had that issue before:
http://www.bing.com/search?setmkt=en-US&q=%22Detected+duplicate+HTTP-based+FlexSessions%22
Hi,James
So great. I have one question about channel configuration in flex side.
In your video, the barList.mxml declared the channelSet, when I remove the channelset, the flex side will throw exception.
Can we ignore the AMF channel in client side?
@wldandan: You can remove config from mxml code, but keep at least service declaration as:
(removing all channel configuration)
Then, you have to add these lines into services-config.xml (in springFlex-server Project):
(removing <services/>)
Fabien from Paris, France.
Hi, fabien
Thanks for your sample. It is great.
@wldandan You need to provide some way / channel for the Flex application to connect to the server. The easiest is the AMF channel.
Hi
thanks for a very informative article ..
i want to know can i display some link as a column in datagrid which will point to some attachment (.pdf,ms excel,ms word etc ) on remote filesystem ?
For sure! You can put a link in the DataGrid that makes a request for the file download.
James, when i connect to a service the follow tag does not exist:
Service Name
I can only see the follow tags:
Service Package
Data Types Package
Why this difference happen between us?
I’m not sure. You might want to try and follow my new Refcard that goes through these steps in more detail:
http://www.jamesward.com/2010/06/14/flex-4-hibernate-3-and-spring-3-integration/
Let me know if that helps.
did not leave the tag that I’m doubtful
here it is
s: AMFChannel uri = “http://localhost:8080/messagebroker/amf
Excellent tutorial, thank you for contributing to community Flex
Hello, I have two queries regarding work that way … The first doubt is when I finish my project and put it on a server the code
s: AMFChannel uri = "http://localhost:8080/messagebroker/amfno way I put it in a variable not to be changing all the time?
If Monday is when I connect the data / service to and appear once more attributes in Java class, data / service will not auto update, bringing me the attribute of the java class for me? Or every time I need to create a data / service new to when this happens?
You need to externalize URLs for real production apps. You can do this manually or use a Flex Framework like Swiz to help you do this.
You can refresh the data services when they change. That should re-introspect the Java classes and update the ActionScript objects.
Hi James,
I am facing few problem, when I am trying to work as per your tutorials.
1. Tomcat – Please let me know- Do I need to download any plug-in for eclipse? I have configure the setting in Tomcat Preferences, even my added manager password also, added into my tomcat package. When I am starting it, through Eclipse, it’s showing everything in same way as I start tomcat directly, but I am not able to look at http://localhost:8080/ as I can when I run directly.
2. I have downloaded BlazeDS (blazeds-bin-4.0.0.14931 as well as blazeds_bin_3-0-0-544) but I am not getting the same files as you are getting. I have only 12 Files. That’s why I am not able to annotate my service as well.
Can you please help me on these issues?
Thanks
Garry
Check out the Flex 4 & Spring 3 Integration Refcard for detailed instructions on how to set everything up.
首先我非常感谢你这教程,在网上找了很多这方面的整合demo.还是你的最简单容易懂.
期待你能做一部hibernate +spring +flex +spring scurity +Cairngorm .haha.我是不是太贪心了啦.
Thanks man! Great example! And thanks for the dependencies!
Great article James, thanks!
A question concerning FB4 standalone. I’ve hooked this install up for using WTP but I don’t have any server definitions. When I try to create a server, there’s nothing there. Downloading server definitions brings back a bunch of them but not Tomcat. I did download a plugin and it’s giving me a Tomcat menu option, but it doesn’t work with the server perspective as usual for Eclipse and WTP.
Has anyone successfully used FB4 standalone, WTP, and Tomcat like you would with an Eclipse, FB4 Plugin, WTP, and Tomcat?
I’d recommend that you install Eclipse, then install FB as a plugin, and then WTP. FB standalone doesn’t have everything in it that some plugins need.
Thanks, yeah that’s what I’m finding.
Hello James,
I’m trying to follow your tutorial but I cannot make the example work.
So when I try to setup the flex project in the last step when I need to configure the J2EE server I do not get to configure the root folder and the root URL but instead I get to configure the context Root, content folder and the Blaze ds war file location. Why is that? And how could I make it work?
Thanks in advance!
I’m not sure why this isn’t working for you. You might want to try and go through my Refcard to make sure you haven’t missed a step:
http://www.jamesward.com/2010/06/14/flex-4-hibernate-3-and-spring-3-integration/
Otherwise email me so I can work with you on figuring out what is wrong. jaward at adobe dot com
Ok thanks James for the replay it was my mistake I have checked in the flex project creation wizard the Create combined Java/Flex project using WTP check box :)
But still in the last step when I hit the Validate Configuration button this message appears “Cannot access the web server. The server may not be running, or the web root folder or root URL may be invalid.”
First I thought I can go on because someone said on a site that it might not function correctly but when I try after the flex project is created to connect to Blaze Ds service I check the no password is required and this appears “Error executing RDS command Status Code 403:forbidden”
By the way the Tomcat server is up and running and the springFlex-server project is deployed on it(this project contains the Blaze Ds in it right?).
Thanks again for your help!
And great work!
Is your RDSServlet uncommented in your web.xml file?
Sorry for the last post. The RDSServlet is uncommented.
It should look like:
Does it?
Yes.
RDSDispatchServlet
RDSDispatchServlet
flex.rds.server.servlet.FrontEndServlet
When the Tomcat starts up the log shows this message
INFO: Initializing Spring FrameworkServlet ‘dispatcherServlet’
Do you get an error when you navigate to:
http://localhost:8080/app/CFIDE/main/ide.cfm
(Replace the port and context root with your values.)
Hello Mister Ward,thanks for all your amazing tutorials they are really helpful.
I have a problem though,when i try to create a new Flex project with BlazeDs and Glassfish v3 i get the same error than George : “Cannot access the web server. The server may not be running, or the web root folder or root URL may be invalid.”
I followed this tutorial to create my web app : http://sujitreddyg.wordpress.com/2009/04/07/setting-up-blazeds/
What can i do please ?
I am desperate,i can’t find an answer.
Can’t you ignore that error and continue with the new project wizard? Or are you getting the error somewhere else?
Thanks for your answer Mr Ward,that’s what i did at first but i wasn’t able to run the project.
It’s working now thanks to your source code,i was a little panicked yesterday and i didn’t see it before posting my message.
Hello, how are you?
Here in the company we are creating several applications that shared the same model, dao, services …
Packages are created outside of the applications containing the three Java classes and then generate the jars of these packages and places them in applications like lib …
But on flex application is not seeing the services that are within the lib folder in a jar …
I go in Flex 4 Date / Services, BlazeDS and when I select the service is not it …. does anyone know if there’s no way to do this? or how can it be done?
I have looked on google but found nothing, imagine put date / Services with Jar, apaece much nothing to do with my problem … if anyone can help me??
I’m not sure what the problem is. But you might want to follow my Refcard to see how you can connect Flex to Java:
http://www.jamesward.com/2010/06/14/flex-4-hibernate-3-and-spring-3-integration/
Hi James,
We want to integrate maven / any other cli script as a post build event to our BlazeDS web service project in order to generate the ActionScript classes for services and value objects. Do you know of a way to do so?
Thank you,
Adi
Sadly there isn’t a way to do this with the Flash Builder Data Wizards. There are some other tools out there that will do this from an Ant / Maven build. One option is the GAS tool in GraniteDS. I hope that helps.
Hi,
Thanks for the quick answer. We are using BlazeDS/Spring on the server side. Do you have any suggestions for a CLI code generation tool?
Thanks!
Maybe check out:
http://insideria.com/2008/12/java-to-actionscript-converter.html
http://www.mslinn.com/blog/?p=133
Mike seems to know a lot about this. Email me if you want me to introduce you to him. jaward at adobe dot com
Hello, how are you?
I have a class in Java that calls student but it extends a class Person …
public class Person (
private TipoPessoa TipoPessoa;
private String name;
private Gender gender;
private TipoCPF tipoCPF;
)
public class Student extends Person (
private String ra;
private DadosContato dadosContato;
private Address enderecoCob;
)
The problem is that in Flex using the Data / Services RDS does not work that way .. when command “import classes VO student looks like this:
[ExcludeClass]
public class extends _Super_Usuario flash.events.EventDispatcher implements com.adobe.fiber.valueobjects.IValueObject
(
model_internal static function
initRemoteClassAliasSingle (cz: Class): void
(
Can anyone help me?
Hi Ricardo,
I feel like there is an open bug for this but I can’t find it. Can you file one:
http://bugs.adobe.com/
Thanks.
Hi, James
I will be very happy if you suggest a solution about displaying a clob database field inside a flex aplication using your tutorial framework (Flex 4, Java, Spring, and Hibernate in Flash Builder 4)
thanks.
What type of data does the clob contain?
Image data(jpeg or bmp) i meant.
Sure! Just turn the clob into a bytearray. Then in flex set the source property of an image to the bytearray.
Hi,
Nice Works !
Can i get the source of the sample projects that your are explaining , along with dependencies.
Check out the Refcard for a sample project that contains the dependencies:
http://www.jamesward.com/2010/06/14/flex-4-hibernate-3-and-spring-3-integration/
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[...] UPDATE 1: Flash Builder 4, BlazeDS 4, and Spring 1.0.3 have all been release so you no longer have to use beta or nightly builds of these products. Use the production versions! UPDATE 2: I’ve done a second part to this screencast that combines Flex 4, Flash Builder 4, Spring 3, BlazeDS 4, and Hibernate 3. [...]