Introduction to Rule Engine

 

Introduction to Rule Engine

 

The rule engine originated from the rule-based expert system, and the rule-based expert system is one of the branches of the expert system. An expert system belongs to the category of artificial intelligence. It imitates human reasoning methods, uses exploratory methods for reasoning, and uses terminologies that humans can understand to explain and prove their reasoning conclusions.

With this feature, business decision-making logic of commercial decision makers and technical decisions of application developers can be separated in the application system, and these commercial decisions can be placed in the central database or other unified places, enables them to dynamically manage and modify during operation, so as to provide effective technical support for enterprises to maintain flexibility and competitiveness.

Simply put, the business logic of a program can be processed through rule configuration.

Open-source rule engines in. Net include:

No.: 1

Rule Engine: drools. net

Description: drools. NET is an open-source Business Rule Engine Based on Charles forgy's Rete algorithm.

Official Address: http://droolsdotnet.codehaus.org/

No.: 2

Rule Engine: SRE

Description: SRE (simple rule engine) is a lightweight open-source, forward-serial reasoning Rule Engine (forward chaining inference rule engine) under. net ). It is easy to understand and can solve complicated problems.

Official Address: http://sourceforge.net/projects/sdsre/

No.: 3

Rule Engine: nxbre

Description: nxbre is. A lightweight Open-Source Business Rule Engine (aka rule based engine) on the net platform, which is a forward-serial inference engine) and XML-driven flow control engine. it supports ruleml 0.9 NaF datalog and Visio 2003 modeling.

Official Address: http://sourceforge.net/projects/nxbre

Open-source rule engines in Java include:

No.: 1

Rule Engine: drools

Description: drools is an open-source business rule engine developed in Java based on Charles forgy's Rete algorithm.

Official Address: http://www.jboss.org/drools/

No.: 2

Rule Engine: jamocha

Description: jamocha is an open-source rule engine developed in Java.

Official Address: http://sourceforge.net/projects/jamocha/

Rules Engine Components

The rule engine is an engine that determines whether a rule can match a real-time condition at the runtime Based on the specified filter conditions contained in the rule to execute the action specified in the rule. There are four basic concepts related to the rule engine. To better understand the working principles of the Rule engine, we will introduce these concepts one by one.

1) Information Unit)

Information Meta is the basic building block of the rule engine. It is an object that contains all information about a specific event. The information includes the message, Application ID of the event generation, event generation event, information meta-type, related rule set, general method, general attributes, and some system-related information.

2) Information Services)

Information service generates metadata objects. Each information service generates information meta objects corresponding to its own type. That is, each metadata object generated by a specific information service according to the metadata has the same format, but can have different attributes and rule sets. It should be noted that many different information services can be run on one machine, and different instances of the same information service can be run. However, in any case, each information service only generates information elements corresponding to its own type.

3) Rule Set)

As the name implies, a rule set is a set of many rules. Each rule contains one condition filter and multiple actions. A filter can contain multiple filtering conditions. A condition filter is a combination of multiple boolean expressions, and the combination result is still a boolean type. When the program runs, the action is executed when the condition filter value is true. In addition to general execution actions, there are three special actions: discard action, include action, and action that persists the content of the information metadata object.

4) Queue Manager)

The queue manager is used to manage queues of Information metadata objects from different information services.

Future Trend of Rule Engine Application

The business world is full of clichés about change. For example, everything will change, and the only thing that remains unchanged is change. In the technical field, the opposite is true. We are still trying to solve the same pile of problems in the software industry 30 years ago-maybe more problems than 30 years ago. Over the past decade, IT practitioners have been overwhelmed by a large amount of literature on software methodologies, such as rapid software development, eXtreme Programming, and agile software development, they emphasize the importance of flexibility and change without exception.
However, business often changes more rapidly than the software processes and technologies on which the development team depends. When Business Planners attempt to restructure the IT department to support the new business transformation, they still feel very difficult.

Which software projects are using the rule engine?

Currently, China Mobile's boss system, enterprise application ERP, CRM, and e-commerce sales systems.