SIP Servlet 1.1 supports Java EE 5. Since then Java EE 6 platform has been released. This includes support for many technologies that relevant to SIP Servlets.
Some examples are:
- Servlet 3.0 enhancements like asynchronous servlets, new annotations (eg: InitParam) and pluggability.
- JNDI namespaces for portable JNDI lookups: java:global, java:module, and java:app
- Context and Dependency Injection APIs.
Java EE 7 is currently again updating the EE platform and it again updates these technologies.
This feature is to update the SIP Servlet API to align with Java EE revisions.