# Drools

**Repository Path**: mirrors/drools

## Basic Information

- **Project Name**: Drools
- **Description**: This repository is a fork of apache/incubator-kie-drools. Please use upstream repository for development.
- **Primary Language**: Unknown
- **License**: Apache-2.0
- **Default Branch**: main
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 15
- **Forks**: 15
- **Created**: 2019-10-22
- **Last Updated**: 2025-09-13

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

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An open source rule engine, [DMN engine](https://kie.apache.org/docs/components/drools/drools_dmn) and complex event processing (CEP) engine for Java™ and the JVM Platform.

Drools is a business rule management system with a forward-chaining and backward-chaining inference based rules engine, allowing fast and reliable evaluation of business rules and complex event processing. A rule engine is also a fundamental building block to create an expert system which, in artificial intelligence, is a computer system that emulates the decision-making ability of a human expert.

Be sure to check out the Apache KIE project [website](https://kie.apache.org/docs/components/drools/) and [documentation](https://kie.apache.org/docs/documentation/)!


Test execution tip
==================

Some test are meant to be executed on machine with _en_US_ locale.
A specific profile is provided to execute them on machines with different locale, namely `test-en`.
There are two ways to activate such profile during maven build:
1. `-Ptest-en` (profile-id based)
2. `-DTestEn` (property based)

The following two commands will execute tests on machine with locale different than _en_US_:

1. `make test -Ptest-en`
2. `make test -DTestEn`

Troubleshooting
================
If the build fails with `UnmappableCharacterException`, set `-Dfile.encoding=UTF-8` for `MAVEN_OPTS` (not as an argument of `mvn` command). Then run `mvn`.

example for Windows:
```shell
set MAVEN_OPTS=-Dfile.encoding=UTF-8
mvn clean install
```

Documenting tips
================

UML diagrams have been used for architectural and design documentation. Those diagrams are in ".puml" format and have been created using the [PlantUML](https://plantuml.com/https://plantuml.com/) tool.
Plugins exists to use it in different IDE:
* [IDEA](https://plugins.jetbrains.com/plugin/7017-plantuml-integration)
* [Eclipse](https://marketplace.eclipse.org/content/plantuml-plugin)
* [VisualStudio](https://marketplace.visualstudio.com/items?itemName=jebbs.plantuml)