High-quality WebSocket client implementation in Java.
This is a sample application created with JHipster, with the Websocket option
Java/Android WebSocket Client
Websocket client library for GWT
A barebones WebSocket client and server implementation written in 100% Java.
A direct access WebSocket API that enables easy integration into a multitude of client technology environments such as scripting and web.
Websocket client classes for Java (primarily targeting Android)