Spring provides a SockJS-less Websocket endpoint at `ws://host:port/socketentry/websocket` without using the SockJS bucket and session URL componets: `ws://host:port/socketentry/{bucket}/{session}/websocket`
Seems like a good starting point. Seems to be similar to Facebook API as used by the spring-android-samples (see FacebookConnectionFactoryin Spring API).
V. Sivaraman, J. Carrapetta, K. Hu, and B. Luxan. Local Computer Networks Workshops (LCN Workshops), 2013 IEEE 38th Conference on, page 56-64. (October 2013)