Release Notes 5.0

OpenRules Release 5.0 essentially simplifies rules repository construction and management and expedites initialization of the OpenRulesEngine. OpenRules-5 introduces rule templates that allow rule designers to completely hide implementation details of the business rules tables. Rule templates are regular rules tables that were usually used in previous OpenRules releases such as this "defineGreeting" rules table:

Rules void defineGreeting(int hour, Response response)			-	Signature with parameters
C1	C2	A1	-	Conditions and Actions identifiers
min <= hour	hour <= max	response.map.put("greeting",greeting);	-	Java snippets describe condition/action semantics
int min	int max	String greeting	-	Parameter types and names
Hour From	Hour To	Set Greeting	-	Business names for conditions and actions

With OpenRules-5 you may define different tables for summer and winter greetings by extending this table-template with particular rules:

Rules summerGreeting extends defineGreeting
Hour From	Hour To	Set Greeting
0	10	Good Morning
11	18	Good Afternoon
19	22	Good Evening
23	24	Good Night

and

Rules winterGreeting extends defineGreeting
Hour From	Hour To	Set Greeting
0	11	Good Morning
12	17	Good Afternoon
18	22	Good Evening
23	24	Good Night

Note that Rules tables "summerGreeting" and "winterGreeting" do not contains technical information at all - Java snippets and signature are defined only once and reside in the template-table "defineGreeting". Any regular rule table may serve as a template (or a base table) for other rule tables that extend it - the only requirement is that base and extended tables should have exactly the same condition and action columns. Both vertical and horizontal rule templates are supported.

While the new rules templatization mechanism is simple and intuitive it brings enormous advantages from the business rules management perspective:

Write once use many times

	Write rules for one state or country and then use them as a template for all other states/countries
	Changes in the implementation of a rule template are automatically propagated to all rule tables that extend this template

Complete separation of business and technical views

	Business people have less to learn (and to be afraid of)
	Technical people have more freedom in rule templates design and maintenance not being afraid to scare their business counterparts by complexity of rules implementation logic
	By placing rule templates and rule tables in separate files you may essentially simplify authorization control and who-does-what assignments

Rules repository becomes smaller and easy to maintain

	Templates allow to avoid a "paste-copy" approach by minimizing the total amount of code and the size of rule tables
	While preserving the same structure changes in the templates and rules could be done independently

Expedited initialization of OpenRulesEngine

	Use of rule templates not only minimizes the total size of rule repositories but contain much less code to be interpreted when OpenRulesEngine downloads all rules for the first time
	Based on the size and design of the existing rules repositories the gain in the initialization time could vary from 2 to 5 times

Libraries of rule templates specific for different lines of business

An ability to create OpenRules template libraries may allow leading organizations in different industries to implement already established business standards such as ACORD for insurances or MISMO for mortgages as a set of Excel-based templates. Even if the library implementers prefers to use their own business models initially they always may change the templates implementation later on without changing the business rules themselves

A similar model will work well for OpenRules OEMs who may define and maintain their rule template libraries in accordance with their latest business object models

Non-intrusive approach

	Rule templates are regular rule tables that were always used in OpenRules repositories. They may include concrete rules and be executed as usual
	All rules repositories created before OpenRules-5 will continue to work without problems (just a little bit more efficiently)

OpenRules 5.0 includes a sample project "HelloJavaTemplates" that demonstrate the use of new features. The web site www.openrules.com as well as the online User's Guide have been modified to reflect the changes introduced by OpenRules-5.