easy-rules/site/user-guide/scheduling-rules-engine.md

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Easy Rules provides APIs to schedule a rules engine using the popular Java scheduler Quartz.

To schedule a rules engine instance, first you need to add the following dependency to your pom.xml:

<dependency>
    <groupId>org.easyrules</groupId>
    <artifactId>easyrules-quartz</artifactId>
    <version>{{site.version}}</version>
</dependency>

Then, you can create a RulesEngineScheduler as follows:

RulesEngine rulesEngine = aNewRulesEngine().build();

Date now = new Date();
int everySecond = 1;

RulesEngineScheduler scheduler = RulesEngineScheduler.getInstance();
scheduler.scheduleAtWithInterval(rulesEngine, now, everySecond);

This will schedule the rules engine to start now and repeat every second.

The RulesEngineScheduler API provides methods to schedule a rules engine:

• At a fixed point of time using scheduleAt(RulesEngine engine, Date when)
• Repeatedly with a predefined interval using scheduleAtWithInterval(RulesEngine engine, Date when, int interval)
• Using unix cron-like expression with scheduleCron(RulesEngine engine, String cronExpression)

To unregister a rules engine, use the following snippet:

scheduler.unschedule(rulesEngine);

You can find a tutorial about scheduling rules engine in the time tutorial.