hi vivek -

transport, global, and service define execution scope.   handlers attached to the 
service chain will only execute for web services requests targetting a specific 
service.  global handlers will always be executed, and transport handlers are only 
executed if a message is recieved by a specific transport listener.

In regards to the application server integration with Axis.  Axis is deployed as a 
servlet inside the WAR file.  the app server passes control to the Axis servlet, the 
servlet invokes handlers then loads the service agent (which in your use case is an 
EJB).  the EJB performs it's work and returns control to the Axis servlet.

Philosophically, i think EJB's should not be directly exposed as a web service but 
rather wrapped behind a stateless session bean. exposing the EJB directly leads to a 
tightly coupled architecture.


As for resources beyond the Axis docs and sources..... the following presentation may 
be helpful
http://www.xmlaug.com/Download/AxisWSEdgeWest2003.pdf

cheers,
/Chris
lead author of O'reillys "Programming Apache Axis"


---------- Original Message ----------------------------------
From: "Vivek Nagulapati" <[EMAIL PROTECTED]>
Reply-To: [EMAIL PROTECTED]
Date:  Fri, 26 Mar 2004 10:52:48 -0600

>Hello All,
>
>I have few questions on the low-level architecture of Axis.
>
>1. According to the architecture guide of Axis, it states that there are 3
>chains of handlers that a MessageContext object has to go through before
>being serviced
>i) Service ii) Global iii) Transport.
>
>IIRC, Service handlers i.e., Request/Response handlers can be used to
>pre-process/post-process SOAP messages. But how can a developer use
>Transport and Global handlers and what is the main purpose of these
>handlers?
>
>2. What would be acting as a transport listener if I deployed the Axis as a
>WAR in a web application server. How does the control get back to the
>Application server if I deployed an EJB component as a web service?
>EJB would be hosted by the application server and web service would be
>deployed in the Axis. So control has to go back to the application server 
>.... how does this work?
>
>Can anyone point/help me in understanding the lower level workings of Axis?
>
>Any tutorials/references would also be appreciated!!!
>
>Thanks,
>Vivek
>
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