Grizzly 2 implements the requirements of RFC 6455, however we do include support for older versions of the protocol. This is particularly useful for clients that haven't caught up with the final draft of the specification. That said, please consider the support for the older versions to be deprecated in favor of pushing support for the final draft. The protocol versions supported at the time of writing are: 6, 7, 8, and 13 (13 being the protocol version of the final draft). We do not support 00/-76, so this may cause an issue with clients such as Safari which are still using this old version of the protocol.

Like other protocols implemented with Grizzly 2.x, WebSocket support is implemented using a Filter. If you're not familiar with the concepts of Filters and FilterChains, please review the documentation in this guide.