# Introduction to Rule Engines with Drools

- Institution: CERN
- Department: CERN Computing Seminar
- Speaker: Mario Fusco
- Year: 2015
- Language: English
- Subjects: Computer science
- Source: [CERN](https://videos.cern.ch/record/3009132)
- Licence: [CERN](http://copyright.web.cern.ch)
- Who can watch: Tweens profiles and older (sources give no ratings; placed by Invisible Network from the source's own words)

In this talk I will present how a rule engine in general and Drools in particular work. After a quick introduction showing the main differences between imperative and declarative programming and describing the most common use cases when the second should be used or at least considered, I will delve in more details into how this concepts have been implemented in Drools and which are its characteristic features including: the Drools Rule Language, the possibility to combine forward and backward chaining, the Truth Management System and the temporal reasoning capabilities (Complex Events Processing). Finally I will demonstrate the new deployment model and substantial improvements to the rule engine's internal algorithms introduced with Drools 6, not forgetting to mention the directions taken in research and development for what regards the future Drools releases.

About the speaker

Mario is a senior software engineer at Red Hat working at the development of the core of Drools, the JBoss rule engine. He has a huge experience as Java developer having been involved in (and often leading) many enterprise level projects in several industries ranging from media companies to the financial sector. Among his interests there are also functional programming and Domain Specific Languages. By leveraging these 2 passions he created the open source library lambdaj with the purposes of providing an internal Java DSL for manipulating collections and allowing a bit of functional programming in Java. He is also the co-author of "Java 8 in Action" published by Manning..

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## Lectures

1. [Introduction to Rule Engines with Drools](https://invisiblenetwork.ai/learn/cern/3009132/683447269411), 1 h 16 min (CERN's player)