Hello,
This is a very interesting discussion. Here at <GX> we built our own
application server on top of servlets, no JSP, no EJB's. This application
server is focused on content management systems. While we are stil happy
using it for almost all our clients, I still intent to go to building sites
using the J2EE technology and methods. The main reason I want this is not
because of technical reasons, but because almost all application server
vendors are going the J2EE way. For example, take a look at Vignette, which
is going to rebuilt their Storyserver on top of J2ee, of Allaire, which is
going to rebuilt its Cold Fusion engine on top of JRun. Also, BEA, IBM and
others are all creating J2EE compliant Application Servers. I know this is
more a long-term, management overview, probably not intented for a single
project, but all these players are going to create reusable components using
EJB. So we have to have experience using J2EE, and especially the EJB part,
even when it's as immature as it is today, in order to take advantage of
them.
Martijn
--
_____________________________________________________________
Martijn van Berkum________ <GX> creative online development
_____________________________________ mailto:[EMAIL PROTECTED]
_________________________________________ http://www.gx.nl/
> -----Original Message-----
> From: [EMAIL PROTECTED]
> [mailto:[EMAIL PROTECTED]]On Behalf Of
> bradley mclain
> Sent: dinsdag 10 oktober 2000 14:57
> To: Orion-Interest
> Subject: RE: EJB vs Servlets
>
>
> hello all,
>
> since it came up, this is an issue that i and our
> other programmer have been wrestling with for a while,
> because like everyone else we feel the pressure to use
> the cool new stuff..and we wonder if the transactional
> and distributed advantages will help us out.
>
> here is my problem. call me dense, but i just don't
> see or mapping being as flexible as i need it to be.
> in all the books the examples tell you that you map
> your object to the table that holds its data. sounds
> fine in theory, but we have some very complex objects,
> and we have a complex relational model, the reason for
> which is to store our data efficiently, not only for
> this application, but also for others. so we have
> objects that need to get their data from different
> tables, even different databases. these objects
> contain collections, single entities, indexes into
> other objects, etc., all of which must be persisted in
> the db. we have solved the problem by writing our own
> dblayer, employing reflection and stashing all our
> queries (as well as caching them and the connections)
> in a static lookup object. this gives us a level of
> control over the data that i cannot see us getting
> from any OR tool, no matter how smart (and remember,
> the smarter something is, the slower).
>
> as to transactional support, we use jts or the db
> transaction services. no problems..
>
> as to servlets, we use exactly one per application,
> mereley to take the requests and to control
> everything--everything else is plain old java classes.
> it is blazingly fast. i cannot believe that looking
> up objects through jndi is going to be as quick as
> looking up my classes in a hashmap.
>
> if i want distribution, i simply break my app into
> multiple apps, run them on separate machines, and use
> the same object model--thats one benefit of oo, right?
>
> i hope someone has the time to refute me completely,
> because, like kevin, i really do want to understand
> what ejb will give me that i cannot live without. my
> greatest concern, as i mentioned above, is OR mapping.
> i have been a dba and a programmer, and i find it
> really difficult to believe that some tool is going to
> produce more efficient and more flexible access to my
> data than i can, given that i currently have full
> control from table to view to sp to accessor methods
> on objects..
>
> bradley mclain
> --usmoving.com
>
> --- "Duffey, Kevin" <[EMAIL PROTECTED]> wrote:
> > Hi Mike (and all),
> >
> > Actually, while Struts is pretty kewl, there are
> > some things that I wish
> > were modified that won't be for reasons of the
> > general population interest
> > instead of my own. Because of this, while I will
> > continue to use Struts at
> > work, my own projects will use my own solution,
> > similar to Struts but not
> > near as robust in some ways, but a bit better on
> > performance. The one thing
> > I really dislike, but I agree with based on what
> > Craig has told me, is that
> > every single form submission causes the
> > auto-population feature to get
> > called (reflection). I only want it to be called if
> > an update occurs. If the
> > user hits cancel to go back, or what not..I don't
> > much care what they just
> > entered. Only when doing searches or updates/entry
> > on forms should it be
> > called. For that reason I am doing my own reflection
> > population routine that
> > does use nested objects. But overall Struts kicks
> > ass in what it offers for
> > a free package.
> >
> > Did I compare Struts to EJB? I didn't mean to in
> > terms of performance.
> >
> > > -----Original Message-----
> > > From: Mike Cannon-Brookes
> > [mailto:[EMAIL PROTECTED]]
> > > Sent: Monday, October 09, 2000 4:12 PM
> > > To: Orion-Interest
> > > Subject: RE: EJB vs Servlets
> > >
> > >
> > > I have to laugh when someone compares Struts to
> > EJBs for performance.
> > >
> > > I've used both and I'd have to say Kevin that if
> > you factored
> > > your code away
> > > from Struts and used EJBs instead you'd have a
> > very VERY
> > > minimal performance
> > > impact (if any noticable at all).
> > >
> > > And looking up EJBs is really very simple two
> > lines of code
> > > (or one little
> > > JSP tag <ejb>).
> > >
> > > Although if you wanted to attach a Swing client to
> > Struts...
> > > you'd have much
> > > greater problem I fear? ;)
> > >
> > > Mike
> > >
> > > PS Struts does have some cool points, I wish
> > they'd break out
> > > the i18n stuff
> > > into another library, it doesn't seem to fit
> > there.
> > >
> > > > -----Original Message-----
> > > > From: [EMAIL PROTECTED]
> > > > [mailto:[EMAIL PROTECTED]]On
> > Behalf Of
> > > Duffey, Kevin
> > > > Sent: Tuesday, October 10, 2000 5:01 AM
> > > > To: Orion-Interest
> > > > Subject: RE: EJB vs Servlets
> > > >
> > > >
> > > > Actually, I know all about it. I have read up on
> > it in
> > > those books and
> > > > others. Infact, we have already separated our
> > code into
> > > those tiers but it
> > > > all runs in the servlet engine. This is what I
> > am talking about.
> > > > I am using
> > > > the Struts framework to allow all forms
> > submitted to a
> > > single controller
> > > > servlet, which then calls upong action classes.
> > Those
> > > action classes then
> > > > figure out what "session" class to call upon.
> > These
> > > "session" classes are
> > > > our logic (ejb) code, but its not in the EJB
> > container..it
> > > runs in our
> > > > servlet engine. It is separated, just not from
> > the servlet
> > > engine itself.
> > > > However, by compexity of building EJBs, I think
> > I mean what
> > > goes into it.
> > > > Instead of a single class, we would have 2 (or
> > is it 3)
> > > interfaces and an
> > > > implementation class. To access it, its not as
> > simple as a
> > > class/reference
> > > > variable to an object in the servlet engine, you
> > have to do
> > > a lookup,
> > > > etc..its a bit more code. Sure..its not terribly
> > complex,
> > > but compared to
> > > > doing it the way we are now, there is quite a
> > bit more work
> > > involved than
> > > > what we are doing now. Also, actually testing
> > and learning
> > > how exactly it
> > > > works is a process that will take a little time.
> > All of these
> > > > things add up.
> > > > What I am wondering is..is it really worth it if
> > supposedly
> > > EJB doesn't
> > > > offer much in the way of performance..it just
> > separates the
> > > logic into a
> > > > separate "tier" of servers. Our code is already
> > separated
> > > long those tiers
> > > > now..and it will probably be easier for us to
> > move to EJB
> > > than those that
> > > > have logic in their servlets.
> > > >
> > > >
> > > > > -----Original Message-----
> > > > > From: Russ White
> > [mailto:[EMAIL PROTECTED]]
> > > > > Sent: Monday, October 09, 2000 11:32 AM
> > > > > To: Orion-Interest
> > > > > Subject: RE: EJB vs Servlets
> > > > >
> > > > >
> > > > > You should read up on J2EE so you can
> > understand what
> > > separation of
> > > > > data/logic/presentation is all about. I would
> > recommend any
> > > > > of the O'Reilly
> > > > > books on the subject(s). Also Development of
> > EJBs is very
> > > > > simple. Especially
> > > > > with a good IDE like VA, Forte, or JBuilder.
> > Orion even comes
> > > > > with a simple tool
> > > > > for creating very useful EntityBeans from a
> > GUI.
> > > > >
> > > > > > -----Original Message-----
> > > > > > From: [EMAIL PROTECTED]
> > > > > >
> > [mailto:[EMAIL PROTECTED]]On
> > Behalf Of
> > > > > Duffey, Kevin
> > > > > > Sent: Monday, October 09, 2000 1:22 PM
> > > > > > To: Orion-Interest
> > > > > > Subject: EJB vs Servlets
> > > > > >
> > > > > >
> > > > > > Hey all,
> > > > > >
> > > > > > I know this is a little off-topic, but
> > seeing as how Orion
> > > > > is about the only
> > > > > > fully compliant EJB server, I figured this
> > would be a
> > > > > better place to ask.
> > > > > >
> > > > > > Lately I have talked to a number of people
> > that have been
> > > > > moving towards EJB
> > > > > > and pulled back because they have found it
> > to be more
> > > > > tedious to develop, as
> > > > > > well as the end result was slower than just
> > using Servlets.
> > > > > >
> > > > > > I ask this because it appears to me that the
> > servlet engine
> > > > > (at least with
> > > > > > 2.2) being able to be failed over,
> > load-balanced, etc,
> > > > > seems to be quite as
> > > > > > capable for scalability and fault-tolerance
> > as the ejb
> >
> === message truncated ===
>
>
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