Release Notes 6.4.1

December 2016



New Book "DMN in Action with OpenRules"

Book "DMN in Action"This practical guide is available from Amazon. Supporting software:

Feb 16, 2017

OpenRules 6.4.1 introduces WHY-Analyzer for Decision Modeling

The Release 6.4.1 introduces a graphical WHY-Analyzer that allows business users to analyze behavior of their DMN-based decision models

Dec 20, 2016

OpenRules Wins 10th International Rule Challenge

OpenRules®  "What-If Analyzer for Decision Modeling" won 10th International Rule Challenge Award at RuleML-2016.

July 8, 2016


Forrester Research, Inc.

"OpenRules have the most-aggressive approaches to business-expert authoring and typically requires less developer support than IBM ILOG, FICO Blaze Advisor, and JBoss BRMS.

Market Overview: Business Rules Platforms



Upcoming Events


DecisionCAMP 2017 July 3-15, 2017, London, UK

BBC 2017, Nov. 6-10, 2017, Orlando, FL, USA

Recent Events

RuleML 2016 and DecisionCAMP-2016, July 6-9 2016, New York

BBC 2015: Nov. 2-6, USA

Video "DecisionsFirst Modeler Integration with OpenRules"

Webinar "Creating and Managing Executable Decision Models"




December 20, 2016

                   Imagine you had a Why Button handy whenever you encountered some disconnect in day-to-day
business operations. Hit the Why Button and presto - answers appear in the form of relevant business rules" - Ron Ross 

OpenRules® Release 6.4.1 adds new capabilities listed below:

"WHY" BUTTON for Decision Modeling: Introduction of Why-Analyzer

OpenRules® Release 6.4.1 introduces a new graphical add-on called "Why-Analyzer" that implements a "Why Button" requested by Ron Ross. It works with decision models built in accordance with the DMN standard. It's much more than just a button but rather a graphical interface that allows business analysts to analyze the results produced by their decision models. See a brief video introduction and try it from here.

Why-Analyzer may download a DMN-based decision model, select a test case and execute the decision model. It provide a friendly graphical interface oriented to a business analyst who wants to analyze his/her decision models. The following picture shows the web interface for the decision model “Loan Origination” described in the Chapter 11 of the DMN standard:

(click on the image to enlarge)

This interface allows a user to select different decision models, execute different test cases and visually analyze produced values of decision variables (with show/hide possibilities) and the rules that were actually executed to produce these values. Read more

Updated Eclipse Plugin

For many years OpenRules provides a special Eclipse Plugin that helps to visually diagnose errors in OpenRules projects placed in the Eclipse IDE. Recent updates to Eclipse are not backward-compatible that created some issues in our plugin. This release fixes all these issue and allows our customers to use the latest versions of Eclipse. Here is example of an Eclipse Plugin view with a live link to the Excel file that contains an error:

(click on the image to enlarge)

You may this example in the project "DecisionHelloWithErros" - see the standard workspace "openrules.dmn".

Support for Long Variables

Our financial customers needed to deal with very large numbers. So, in this release we added support for variables of the standard Java type "long" which can be used when the standard "int" variables are not big enough. The largest integer variable is 2,147,483,647 and when you try to multiply two really big integers you may get an overflow situation (that unfortunately may go unnoticed). The largest long value is 9,223,372,036,854,775,807 and will be very helpful in such situations. You may use the type "long" directly in your Data tables or in Java objects, and they would be recognized by OpenRules. When you use long variables inside decision table expressions, you have two choices as on the following picture:

Here we use "long" variables "Cost" and "Total" and "int" variable "Rate". As you can see we introduce a new macro %L{long-var-name} for long variables.

The standard workspace "openrules.decision" includes a new sample project "DecisionLongIntegers" that demonstrates how to use long variables.

Simplified Organization of DMN Sample Projects

The release 6.4.1 comes with an essentially updated workspace "openrules.dmn" that becomes OpenRules main sample repository. The majority of sample projects are oriented to business users and do not include Java code at all. So, we also made it easy for business people to use the folder "openrules.dmn" with the basic Window File Explorer. To run these projects , business users even do not have to install Apache Ant and simply make changes in Excel and double-click on "run.bat". The project specific information can be defined in the file "define.bat". Here is how this file look for the project DecisionHello:

There are also examples that include Java sources to explain how they can be integrated with IT. These project allow a developer to create, modify and compile Java classes by adding one more variable "CLASS_NAME" to the file "define.bat" and using "build.bat". The developers will need to install Apache Ant and look at the project "DecisionHelloWithJava" as an example.


Updated Web Projects

We updated all sample web projects in the workspaces "openrules.dialog" and "openrules.web" by removing all (direct and indirect) references to the global construct "dialog()" that was deprecated in the Release 6.3.3 of May 15, 2015. If you still use this construct in your OpenRules Dialog/Web projects, please replace it as it was recommended almost two years ago. All projects were tested with the latest version of Apache Tomcat and the defaults target folder in the file "" is now called "C:/apache-tomcat" (instead of the old "C:/apache-tomcat-6.0").


Download the latest complete OpenRules® release 6.4.1 from here.

If you have any questions, comments or suggestions, please post them at the Google Discussion Group or send them directly to




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