CometD 2 Java
CometD Java Implementation
The CometD Java implementation is based on the popular Jetty Http Server and Servlet Container, for both the client and the server.
The CometD Java implementation, though based on Jetty, is portable on other Servlet 2.5 compliant servlet containers (because it uses the portable Jetty Continuation API).
The war file resulting from the development of your CometD web application can be deployed to other Servlet 2.5 compliant servlet containers, but it will scale less because it will be less integrated with the servlet container.
When deployed to a Servlet 3.0 compliant servlet container, the CometD implementation will make use of the asynchronous features offered by the servlet container and will be fully portable and scalable (the scalability will be as good as the servlet container's implementation).
See this FAQ entry when deploying to Servlet 3.0 compliant servlet containers.
The CometD Java Implementation offers a client library and a server library, documented in details in the following sections.