Hi, I wonder if it is easy to make a Avalon component run within Phoenix and within any EJB-Container interchangable by making the component a EJB. This way using the features of the container for any component. Is there allready a component that works as a 'gateway' to EJB-applications? Or how would I realize an integration into existing EJB-based systems that use anycommercial container.
Am I right that Phoenix (or the Component look up mechanism at all) is using an rmiRegistry for lookup? Actually I am more interested in JMS than in EJB. How does JMS match with Avalon? Does it make sense to use both in an integrated way? JMS seems to have a potential for scalable distributed (server-)applications. But JMS uses JNDI for lookup. And when do I use JMS and when Avalon to do a lookup/kommunication? Maybe there might be an interface a block can implement that makes tha block able to send and consume messages? Hm! As Peter said, SOAP seems to be the perfect way to integrate with non java (especially Microsoft) environments. Thanks, Michael -----Original Message----- From: Peter Donald [mailto:[EMAIL PROTECTED] Sent: Monday, August 06, 2001 8:49 AM To: Avalon Development Subject: Re: avalon and soap On Mon, 6 Aug 2001 16:07, fanyun wrote: > After study avlon for 1 week, I feel it provide a way programmer can build > seperated software blocks and configure them to work together using XML. I > wonder is it just like using Soap Services to build application. Or like > the way EJB works. > > Can any one explain what is the difference between these 3: Avalon, Soap, > EJB I can try ;) Avalon/Phoenix and EJB are both *software* service APIs. They describe a way to implement services. The difference is the type of services they can implement. EJBs are restricted to buisness object services (Session and Message beans) or data facades (Entity beans). EJBs also impose restrictions on what you can do (threading, file access, net access). EJBs are also inherently a "request/response" API. A "user" makes a resquest and gets a response (possibly asnchronously via MessageBeans). The containers can make all sorts of optimizations to optimize performance (multiple instances of each service etc). EJBs are generally useful for writing buisness objects and their support - they can be shoehorned into other realms but that is not their strength. Avalon/Phoenix is a more general "service" API. In it you create components that provide services (to other software components). The API is not designed around request/response cycle and each component can manage their own threads and activity levels. The container also does not try to manage other aspects (like replicating blocks across multiple servers or anything like that). It is more aimed at creating "servers" and would be a perfect base on which to build an EJB server. SOAP is an XML format for RPC calls generally used in construction of "web" services. What this means is that EJBs could be used as software component and could talk using SOAP protocol to other distributed components (that could be written in anything from Avalons blocks to MSes COM+ components to python CORBA objects). I think I got that right but I am not an expert in EJB or SOAP so ... ;) Cheers, Pete *-----------------------------------------------------* | "Faced with the choice between changing one's mind, | | and proving that there is no need to do so - almost | | everyone gets busy on the proof." | | - John Kenneth Galbraith | *-----------------------------------------------------* --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
