feature-rich Java event bus optimized for high-throughput

 MBassador is a light-weight, high-performance event bus implementing the
 publish subscribe pattern. It is designed for ease of use and aims to be
 feature rich and extensible while preserving resource efficiency and
 performance.
 .
 The core of MBassador is built around a custom data structure that provides
 non-blocking reads and minimized lock contention for writes such that
 performance degradation of concurrent read/write access is minimal.