This week The apache Ignite book becomes one of the top books of leanpub

This week The apache Ignite book becomes one of the top books of leanpub.


Best practice for writing effective business rules on Ilog Jrules

Documentation which supplied with Ilog Jrules is very much helpfull to write business rules. However, to write better business rules on Ilog Jrules, we might follow some best practice, which will help us to write and manage our rules. In the current post i would like to share my experince with Ilog Jrules as a best practice guide:
1) Follow java naming conventions when creating java class which will converted to BOM. Best approach will be create class with all its functionality.
2) Use rule packages, because on ruleflow you can use rule packages to contol running business rules effectively. However by default all rules under one package will run, you can use dynamic rule selection to select and run any particular business rules.

3) Use ruleflow task to initialize any global variables, it's not good idea to auto generate variable for any bom.
4) Also it's very usefull to use task for rule packages to intialize bom which will prticipate in the current package.
5) In many cases it's very use full to use task of ruleflow to define metadata which will take part of all business rules over the project. It's may be load any extra data from database tables or from ftp. However task of ruleflow only support java 1.4.
6) Use custom java class with static methods over virtual methods. Becuase it's a huge trouble to manage whole BOM with virtual methods in any extrem projects. During update of BOM you could lost your all virtual methods.
7) In BAL, when working with collections, use clause to filter as much element of collections as possible.
set 'personAddress' to serviceUtils . getAddressesFV ( the id of paramPerson )
where each IDWAddress FV is not null
and ( the city of each IDWAddress FV is not null
and the city of each IDWAddress FV is not empty
and utils.upperCase(the city of each IDWAddress FV) contains cityLookedFor ) ;

8) To use collection properly in BAL, you must use Collection interface rather then any implemented class. In version 6.7.2 there are also some bugs related with collections. One of the bug as follows, when calling any xom method with two collection parameters, Jrules mixed the two collections elements on first collection.
9) Write java utility class with static methods to use in BAL, for example compare two collections, check empty collections, check null values. Utility methods help you to write better effective business rules.
10) Use category filter to filter your boms, when you have a lot of classes with similar methods.
11) When using decision tables or decision tree, use precondition to check variable or paramerters which will take part of that rules, because it's realy hard to debug decision tables and tree.
12) In case of similar business rules, i prefared to use tempate for creating rules. It not only help to create rules from the scrach but also you can define category filter effectively for different users.
13) Use documentation field of any business rules to document the rules. I found it very help full when explains ours analyst to create similar rules in team server.
14) Use maven or ant script to create or update IrlSessionBean with your custom java libraries to invoke business rules in execution server.
15) Use j2se client to test the business rules before deploy it in execution server.