Blog Archives

01: Drools tutorial with Maven and Eclipse

Drools is an open source rules engine that allows you to externalize the business rules.

This tutorial assumes that you have gone through “Setting up Java, Maven, and Eclipse.” Once you have gone through the following steps, you should have a project structure as shown below.

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02: Drools tutorial — A non trivial example with step by step instructions

Drools allow you to externalize business rules to a database, excel spreadsheet, etc. In this tutorial let’s look at an OrderItem scenario where  each OrderItem needs to be put through a couple of rules to determine its discounted price. Step 0: Dependency jars an structure Step 1: … Read...

03: Drools with Decision tables (Excel spreadsheet) tutorial

This is an extension to Drools tutorial with Maven. This externalize the rules criteria to an Excel spreadsheet license.xls. This means the age condition is supplied in the xls file under src/main/resources/drools/license.xls. Step 1: Maven pom.xml file dependencies. … Read more ›...

04: Drools with rules in an excel spreadsheet – Data validation

This tutorial uses Drools as a validation engine to validate an input csv file. The rules are maintained externally in an excel spreadsheet. Step 1: Create a new Maven project “-B” means interactive mode is false. Import it into eclipse or IDE of your choice as a maven project. …...

05: Drools with rules in an excel spreadsheet – Global variables & variable capture

This extends 04: Drools with rules in an excel spreadsheet – Data validation .

Step 1: Enhance the POJO with “actualValues” field and “getFieldValue(String fieldNames)” method.

Step 2: trades-rules.xls with “

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