Oracle Server E10293-02 Benutzerhandbuch

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SIP Servlet Environment
SIP Servlets  2-5
SIP Servlets and SIP Applications
A SIP application is a J2EE-compliant application accessed over the SIP protocol. 
Applications are triggered by an inbound SIP protocol request, just as Web 
applications are triggered by an inbound HTTP protocol request.
An application has a protocol interface such as SIP or HTTP (presentation tier) that 
reaches servlets and other business objects (logic tier) which in turn are managed and 
have resource connections to the database (data tier). User and application data are 
accessed through the data tier which is represented by applicable parts from the J2EE 
specification. Applications are delimited by the scope of the deployment descriptor, 
the sip.xml file.
SIP Servlet Environment
This section describes the environment of a SIP servlet and what occurs during both 
the startup of the application server (AS) and when a request enters the SIP Container. 
Figure 2–2  The SIP Container at Startup
1.
The following occurs at startup:
a.
The container reads the deployment descriptor (sip.xml).
b.
 is created.
The global init parameters are set. These are marked with 
<context-param>
 in the sip.xml file.
Session Configuration values are set. These are marked with 
<session-config>
 in the sip.xml file.
Proxy Configuration values are set. These are marked with 
<proxy-config>
 in the sip.xml file.
The container instantiates the TimerListener, 
SipApplicationSessionListener
SipSessionActivationListener
SipSessionAttributeListener
, and the SipSessionListener. 
Each listener has one instantiation (if defined).
c.
A Servlet Config object is created. The Servlet Config holds all init parameters 
per servlet. These are marked with <init-param> and are set per servlet in 
the sip.xml file. It also includes the global init parameters 
(context-param).