The document provides an overview of Drools Expert and Fusion, including when to use Drools, its key features, examples of use, and information about the Drools community.

1. What a rule-based program is Drools Expert & Fusion Declarative (What to do) Vs. Imperative (How to do it) When should you use Drools? The problem is beyond any algorithmic

2. solution or isn't fully understood

3. The business-logic changes often

4. Domain expert or business analysts are readily

5. available but are nontechnical

6. You want to isolate the key parts of your logic

7. especially the really messy parts Complex Event Processing with Drools Fusion Understands and handles events as a first

8. class platform citizen (specialized Facts)

9. Selects a set of events in a cloud and detect

10. the relavant relationships among them

11. Takes appropriate action based on the patterns

12. detected and the events' temporal relationships rule &quot;Acknowledgement Failure&quot; when $req : BuyReq() not BuyAck( this after[15s] $req ) then channel[ &quot;alerts&quot; ].send( new Alert( $req ) ); end rule &quot;Buy More Stock” when TradingWindow( status == OPEN ) Accumulate( $t : Ticker( name == “RHT” ) over window:time(4m), $avg : avg( $t .price ) ) eval( $avg > 100 ) then channel[ &quot;buy channel&quot; ].send( new BuyReq( &quot;RHT&quot; ) ); end rule &quot;Check age&quot; when $a : Applicant( age < 18 ) then modify( $a ) { valid = false } end Features Made up of discrete rules, each of them

13. models a specific aspect of your domain