Chapter 4. Producing the events
We’ve heard that a million monkeys at a million keyboards could produce the complete works of Shakespeare; now, thanks to the Internet, we know that is not true.
Robert Wilensky
In chapter 2 we discussed the architecture of event processing applications and introduced the model that we are using to describe event processing systems. In this model, and in the majority of event processing systems, there is a distinction between entities that introduce event objects into the event processing system (event producers), the software artifacts that process the events (event processing agents, or EPAs), and the entities that receive the events after processing by the event processing system (event consumers).
We now continue our detailed examination of event processing applications by looking at event producers; we discuss event consumers in chapter 5 and event processing agents in chapter 6. In this chapter we examine the following:
- The notion of an event producer, its role, and the definition element describing it
- The different kinds of event producers
- The different ways of interacting with an event producer
We also include a specification of the event producers used in the Fast Flower Delivery application. We start by defining the event producer.