A @SipApplication annotation is used in ClickToDial to define a set of SIP servlets used together to provide SIP functionality. The @SipApplication annotation is set at the package level by putting it in the package-info.java file in the clicktodial.sip package.
@javax.servlet.sip.annotation.SipApplication( name="ClickToDial", mainServlet="RegistrarServlet") package clicktodial.sip;
The @SipApplication annotation sets two elements: the name of the application, and the main servlet. The name element is required, and is set to the application name. The optional mainServlet element defines which SIP servlet will initially respond to SIP requests. In this case, the RegistrarServlet, which registers SIP clients so they can be later contacted for calls, is the main servlet for ClickToDial.