Deadlock Analysis of Wait-Notify Coordination

Deadlock analysis of concurrent programs that contain coordination primitives (wait, notify and notifyAll) is notoriously challenging. Not only these primitives affect the scheduling of processes, but also notifications unmatched by a corresponding wait are silently lost. We design a behavioral type system for a core calculus featuring shared objects and Java-like coordination primitives. The type system is based on a simple language of object protocols -- called usages -- to determine whether objects are used reliably, so as to guarantee deadlock freedom.