Oracle Server E10293-02 User Manual

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SIP Servlet Environment
2-6  Oracle Communication and Mobility Server Developer’s Guide
d.
The servlets are created and initiated with the init parameters prepared by the 
Servlet Config. Each servlet is run as one instance. The init method in the 
servlets is executed.
e.
A SIP Application Manager, which contains a reference to 
SipApplicationSessions
 and the SipFactory, is created.
Figure 2–3  Initial Requests Processed by the SIP Container
2.
The container distinguishes between initial requests and subsequent requests, 
where initial requests invoke a servlet depending on the invoke conditions (or 
rules) of the servlet and subsequent requests get forwarded directly to the same 
servlet as invoked for the initial request. At an Initial Request, the following steps 
occur:
a.
The container chooses a specific application based on the handling described 
in "Handling Initial Requests".
b.
Which servlet to invoke is decided by evaluating the rules of each servlet in 
the servlet invocation order (
). The rule execution order is decided 
by the order of the <servlet-mapping> order for each servlet in the 
sip.xml
 file. The servlet with the top-most servlet mapping is the one that 
get the rules checked first. For more information, see the following section, 
c.
A SIP Application Session is created together with a SIP Session.
d.
A transaction and a request are created and associated with the SIP session 
object just created.
3.
For a subsequent request, one for which the container already holds a dialog (a 
dialog is defined by the Local-tag + Remote-tag + CallId), the request is forwarded 
to the same servlet executed at the initial request. The request works with the 
same Message Context (SIP-Application Session + SIP-Session) as it had in the 
initial request.