Develop Event Based Applications using Esper
By admin on Jul 21, 2008 in .NET, Java, open source
As quoted from the website, Esper is an Event Stream Processing (ESP) and event correlation engine (CEP, Complex Event Processing). Targeted to real-time Event Driven Architectures (EDA), Esper is capable of triggering custom actions written as Plain Old Java Objects (POJO) when event conditions occur among event streams. It is designed for high-volume event correlation where millions of events coming in would make it impossible to store them all to later query them using classical database architecture.
It is available for Java as Esper, and for .NET as NEsper.
The Esper engine has been developed to address the requirements of applications that analyze and react to events. Some typical examples of applications are:
- Business process management and automation (process monitoring, BAM, reporting exceptions, operational intelligence)
- Finance (algorithmic trading, fraud detection, risk management)
- Network and application monitoring (intrusion detection, SLA monitoring)
- Sensor network applications (RFID reading, scheduling and control of fabrication lines, air traffic)
Developing event-driven application is not hard using Esper.
- Define the mission of your application by analyzing your business domain and defining the situations to be detected or information to be reported
- Define your performance requirements, specifically throughput and latency
- Identify where events are coming from
- Identify lower level event formats and event content that is applicable to your domain
- Design the event relationships leading to complex events
- Instrument your sources of events
- Design how you want to represent events: as Java classes, as Maps, or as XML events
- Define EPL statements for patterns and stream processing
- Use the CSV adapter as an event simulation tool, to test situations to be detected, or to generate to load
- Test against your performance requirements: throughput and latency in your target environment
