I disagree somewhat with this. I think that XML over HTTP can be looked at as a relatively simple way to use "distributed service" or "distributed component" architecture. EJB's as distributed components are a more complex implementation and more limited.
I've seen a number of distributed apps architected this way - it's simpler, easier to understand and debug, and much easier to integrate with non-Java technologies. Imagine the following: 1. A user clicks on a web page requesting a resevation. 2. The server processing that page is written in Perl (or Python or whatever). Upon processing the input, it crafts a URL something like: http://www.RemoteService.com/reservations/processRequest.cfm?<?XML 1.0><!DTD (dtd reference)><ResRequest><param1>abc</param1></ResRequest> 3. The Perl program THEN EXECUTES AN HTTP "GET" using the request it generated above. The request (in this example) could be processed at the remote server by a Cold Fusion application (or whatever) which parses the XML record and uses the information to connect to an EJB container if desired and process the reservation. 4. The Cold Fusion program then passes back the results in another XML record. 5. The originating Perl program gets the result of its XML query back as an XML record. It parses the XML and uses the information in it to craft the page to send back to the client browser. NET RESULT: Apps written in any language that can speak HTTP and parse XML can communicate this way. And it's easy. And it allows you to publish and enforce the system interface using XML/DTDs. This is a big deal. There is no mature, easy-to-use equivalent for defining the passing of objects between systems. Using EJB to publish a remote service pretty much requres using a technology that can access an EJB using RMI/IIOP (or potentially Corba). This is difficult, limiting and expensive. If I were architecting an app that was planned to be a "remote service" or "distributed component", I'd define and publish the system interface using XML/DTDs and make the app available over HTTP - and use EJB's for processing behind the scene if required. --- John Harby <[EMAIL PROTECTED]> wrote: > Yes, IORs can be transferred in the same tunnelling > fashion as the > others. Visibroker Gatekeeper is one product that > provides this. > > >From: SureshBabu Sreeramulu > <[EMAIL PROTECTED]> > >Reply-To: [EMAIL PROTECTED] > >To: [EMAIL PROTECTED] > >Subject: Re: XML over Http vs EJB technology > >Date: Thu, 1 Nov 2001 10:20:00 +0530 > > > >Can IIOP pass through the firewall ? > > > >Regards > >Sureshbabu > > > > -----Original Message----- > > From: Peter J. Braswell > [SMTP:[EMAIL PROTECTED]] > > Sent: Wednesday, October 24, 2001 10:09 > PM > > To: [EMAIL PROTECTED] > > Subject: Re: XML over Http vs > EJB technology > > > > Sacha pretty much hit the nail on the head > here... > > > > The only thing I wanted to add is that > XML/HTTP may be a candidate > >if you > > have to go through a firewall. This can > be done with RMI, but is > >tricky. > > > > cheers, > > peter > > > > -----Original Message----- > > From: A mailing list for Enterprise > JavaBeans development > > [mailto:[EMAIL PROTECTED]]On > Behalf Of Sacha Labourey > > Sent: Thursday, October 25, 2001 12:02 PM > > To: [EMAIL PROTECTED] > > Subject: Re: XML over Http vs EJB > technology > > > > > > Hello, > > > > XMLovHTTP is not really a model but just > another protocol compared > >to RMI, > > CORBA, DCOM, ... > > > > Some J2EE server provide many different > protocol connectors (RMI, > >CORBA, > > SOAP, ...) > > > > Consequently, XMLovHTTP can be used with > many different server > >side > > technologies (that is the goal of this > protocol!) such as J2EE, > >.NET, COM+, > > ... and J2EE can use many different > protocols. > > > > Thus, there is nothing such as "XMLoHTTP > vs. EJB" but more > >"XMLoHTTP > >WITH > > EJB" > > > > Cheers, > > > > > > Sacha > > > > > > > > > -----Message d'origine----- > > > De : A mailing list for Enterprise > JavaBeans development > > > [mailto:[EMAIL PROTECTED]]De la > part de Catalfano > >Anthony > > > Envoy� : jeudi, 25 octobre 2001 17:52 > > > � : [EMAIL PROTECTED] > > > Objet : XML over Http vs EJB technology > > > > > > > > > Does anyone have any reference > information contrasting these two > >models. > > > > > > > > > Thanks > > > > > > Anthony Catalfano > > > Information Technology Analyst > > > Deere & Company > > > 309-748-5201 > > > > _________________________________________________________________ > Get your FREE download of MSN Explorer at > http://explorer.msn.com/intl.asp > > =========================================================================== > To unsubscribe, send email to [EMAIL PROTECTED] > and include in the body > of the message "signoff EJB-INTEREST". For general > help, send email to > [EMAIL PROTECTED] and include in the body of the > message "help". > __________________________________________________ Do You Yahoo!? Make a great connection at Yahoo! Personals. http://personals.yahoo.com =========================================================================== To unsubscribe, send email to [EMAIL PROTECTED] and include in the body of the message "signoff EJB-INTEREST". For general help, send email to [EMAIL PROTECTED] and include in the body of the message "help".
