The Runtime Environment

Runtime, with regards to the YAWL environment, refers to the period when the YAWL System is active and executing – the host server is operational and the Engine is running in its servlet container (Apache Tomcat by default), accepting requests from Custom Services and applications to load specifications, start process instances (or cases), check out work items, and so on, generating events and progressing cases as per their control-flowtowards conclusion.While much of what occurs during runtime is described in other chapters, most of the internal operations have been hidden. This chapter emphasizes the internal execution mechanisms of the YAWL Engine.