questions about SCEA part II

[Sorin Alexandru]

Dear all,

What are the technologies accepted to develop the project for SCEA part II ?
Is Struts ok ? Is JSF ok ? Can one use just jsp/servlets ? E.g. suppose I need to implement a login mechanism, which I can do using the Intercepting Filter pattern by adding a filter in a standard servlets solution, or by extending the RequestProcessor when using Struts or again adding a filter in JSF.
Are all these accepted ? If so, which technology is recommended/encouraged/appreciated more ?

What about EJB ? Is only EJB 3.0 accepted ?
Can one use web services ?

Thank you,
Greetings,
Sorin

[Ionut Bucurescu]

You are not restricted to use a certainly web applications framework. I've read on this forum about people that passed the exam using all of the frameworks specified by you. I've notice also that a lot of them used only Servlets and JSP. You can use any released version of the JEE APIs and also web services.
http://www.sun.com/training/catalog/courses/CX-310-301A.xml

[Ghajini Johnson]

Login mechanism - if this is part of your functionality dont use it in filters. Thats not a good idea. Filters and intercepting filters must be used which are not necessarily part of the application functionality.

[Sorin Alexandru]

Ghajini Johnson wrote:Login mechanism - if this is part of your functionality dont use it in filters. Thats not a good idea. Filters and intercepting filters must be used which are not necessarily part of the application functionality.

Hi Ghajini,

Could you please be more specific ? What do you mean by "part of your functionality" ? My example refers to a standard authentication mechanism - username and password. For each page a user accesses you'd need to check if he/she is logged in. You do this typically with a filter. Don't you agree ?

Greetings,
Sorin

[Ghajini Johnson]

If checking whether the user is logged in by any specific cookie or session info, it is okay, but for initial login authentication, which should be specific to each application and essentially login is part of functionality, so initial authentication need not be done in filters. Once cleared, thereby you can intercept every request, and see whether user is authenticated.

[Sorin Alexandru]

Ghajini Johnson wrote:If checking whether the user is logged in by any specific cookie or session info, it is okay, but for initial login authentication, which should be specific to each application and essentially login is part of functionality, so initial authentication need not be done in filters. Once cleared, thereby you can intercept every request, and see whether user is authenticated.

Yes, that's clear. For the login functionality itself you'd use a special jsp page or servlet (to give an example) that checks in a DB the respective username/password and if found, it adds a bean instance to the session object. After that, a filter can be used to check the presence of the bean in the
session.
This mechanism can be implemented with Struts, JSF or pure jsp/servlets. I understand that all these solutions are accepted for SCEA part II. Still, is any of them "the preferred way" ?

Thanks,
Sorin

[Ghajini Johnson]

Selecting JSF Vs JSP or JSP Vs servlets - it is upto your problem statement.

All of these things can do the job, but there are finer prints on each. Any JEE technology can be used for solution. Your selection matters.

[Bill Zelan]

Probably you need to use ejb3 and jsf instead of struts or springframework, as this is an exam from Sun

[Sorin Alexandru]

Bill Zelan wrote:Probably you need to use ejb3 and jsf instead of struts or springframework, as this is an exam from Sun

Sun shouldn't care about this, right ? If your solution is correct, does the technology matter ?
But probably they are biased, so I guess you should use Sun technologies, indeed.

[J J Wright]

so I guess you should use Sun technologies, indeed.

My advice to you is focus on the problem. Select the technology based on the requirements not on whether it originated from Sun.

[Sorin Alexandru]

Jonathan Aotearoa wrote:

so I guess you should use Sun technologies, indeed.

My advice to you is focus on the problem. Select the technology based on the requirements not on whether it originated from Sun.

That's quite clear, but in most cases you can't select the technology based on the requirements, because the technologies are equivalent.
So for a given requirement, you could in principle select any technology. If that was not the case, it would mean the requirement is poorly specified.

But maybe I misunderstand you, so can you please give examples of such requirements ?

Or by "requirement" do you mean something like: "you have to use JSF" ? In that case, it's clear what you have to do ....

[J J Wright]

By requirements I mean the nature of the application you've been assigned to design and the non-functional requirements you've been asked to fulfill.

...you can't select the technology based on the requirements, because the technologies are equivalent.

I disagree. Competing technologies may target to the same problem, e.g. building web applications, but they're never equivalent. They all have their strengths and weaknesses.

[Sorin Alexandru]

Jonathan Aotearoa wrote:By requirements I mean the nature of the application you've been assigned to design and the non-functional requirements you've been asked to fulfill.

...you can't select the technology based on the requirements, because the technologies are equivalent.

I disagree. Competing technologies may target to the same problem, e.g. building web applications, but they're never equivalent. They all have their strengths and weaknesses.

It would help a lot if you could give examples of such requirements. Or just if you could be more concrete.

Thanks,
Sorin

[J J Wright]

For example.

Are you being asked to design a complex user interface where lots of ajax enabled components might be appropriate, or are you being asked to design an application which, for the most part, only displays large amounts of effectively read-only data?

If performance is a critical NFR, how performant are the competing technologies and/or frameworks?

[Sorin Alexandru]

Jonathan Aotearoa wrote:For example.

Are you being asked to design a complex user interface where lots of ajax enabled components might be appropriate, or are you being asked to design an application which, for the most part, only displays large amounts of effectively read-only data?

If performance is a critical NFR, how performant are the competing technologies and/or frameworks?

Fine. You can do Ajax from a JSP (in a JSP/servlets implementation), or from Struts or from JSF, or GWT, or Flex, etc. So again, all these solutions are possible and from the performance point of view there's no difference (you're still using Ajax).

Sorin

[J J Wright]

If you're of the opinion that all the options you listed have exactly the same performance, scalability, and memory usage characteristics, then pick some other defining attribute(s) such as ease of development, available expertise etc.

[Sorin Alexandru]

Jonathan Aotearoa wrote:If you're of the opinion that all the options you listed have exactly the same performance, scalability, and memory usage characteristics, then pick some other defining attribute(s) such as ease of development, available expertise etc.

Yes, I agree with that.

Sorin