JSR 340 has released an Early Draft of the Servlet 3.1 specification.

Other than the usual clarifications and javadoc updates, ProtocolHandler and WebConnection are new classes that encapsulates the protocol upgrade processing. This will typically be used for upgrading an HTTP connection to a WebSocket. Section 2.3.3.5 in the specification provide more details on it.

Section 3.7 explain non-blocking request processing by the Web container. ReadListener and WriteListener are new interfaces that represents a call-back mechanism to read and write data without blocking.

As with other Java EE 7 specifications, progress can be tracked at servlet-spec.java.net. The Expert Group discussions are archived and you can participate by sending an email to [email protected].