In a running ECS, most major objects are a part of a single object hierarchy, extending the class com.eventgnosis.system.SystemObject. Specializations of SystemObject fall into one of the following four basic categories:

• Event Sources: convert events from a given input protocol into an internal, proprietary EventGnosis information schema. Generally on the edge of the system, pulling events into the ECS.
• Event Destinations: convert from the internal, proprietary EventGnosis information schema to the outbound protocol. Generally on the edge of the system, pushing ECS-generated events to outside entities.
• Filters: cohesive units of functionality that perform well-defined tasks on event streams flowing through the system. Filters are often chained together inside Filter Stacks to solve specific application problems. Filters exist for editing Events, routing, and complex correlation and matching functions.
• Managers: objects in the managed object hierarchy that do not process events but oversee the lifetime (startup, running, monitoring & shutdown) of major subsystems relating to the preceeding three categories (sources, filters, destinations). Management tasks are delegated to each of the major sub-system managers: sources, adapters, filters, destinations, queues and overall control (the root object).

The lifetime of each SystemObject is managed by its parent through a simple hierarchy of SystemObjects. At the very top (root) is the RuntimeController SystemObject, which is responsible for overall system startup, running and shutdown. Directly under the RuntimeController are the various management SystemObjects for the major system areas (Sources, Adapters, FilterStacks, Destinations, Queues, Configuration). Each of these managers in turn handles the lifetime of its children by creating, monitoring and shutting them down, if necessary.

Finally, under each of these managers exist SystemObjects according to their classification. See accompanying “Runtime SystemObject Hierarchy” PowerPoint diagram. There are additional lower level hierarchies for filters, which exist under a threaded parent filter stack, as well as Source implementations where a protocol can have a pool of slave listeners.

These objects are then horizontally connected to each other by their destination attributes, resulting in an interconnected, directed graph of “worker” objects which manage & route events through the system. This complex graph is configured according to a set of ECA’s at startup.