6.4. Event Admin shortcomings

As you’ve seen, an event-driven architecture allows you to better decouple your applications. The Event Admin service provides you with a simple way to achieve this architecture, but there’s a price to be paid for this simplicity. In this section, we’ll explore several shortcomings of the Event Admin service. We’ll look at ways of solving some of these problems if you’re brave enough to extend or perhaps implement your own Event Admin service.

6.4.1. Losing events

Let’s revisit our travel agent use case and consider the scenario where the machine crashes as the car rental application is processing the travel event posted by the travel agent application. When the machine comes back up, the whole process will have to commence again, as shown in figure 6.11. The original travel event was lost while it was being consumed, and a new event needs to be sent.