Obtaining Rules Engine Instance

Use

You obtain rules engine instance to allow the Lean Rules Engine to execute the rules content. While obtaining an instance, you can configure the following rules engine properties including the business log level property.

RuleEngineFactory.POLLING_FREQUENCY - Represents the time interval in milliseconds to poll the repository for any changes in the rules. Default value is 180000.
RuleEngineFactory.NETWORK_CACHE_SIZE - Represents the maximum number of different rulesets whose networks will be cached. Default value is 50.
RuleEngineFactory.INITIAL_POOLSIZE - Represents the initial pool size of the rules engine. Default value is 1.
RuleEngineFactory.MAXIMUM_POOLSIZE - Represents the maximum number of simultaneous requests for each ruleset that can be handled without blocking. Default value is 10.
RuleEngineFactory.POOLSIZE_INCREMENT - Represents by what size the pool should be incremented if the existing pool reaches the maximum pool size. Default value is 0.
RuleEngineFactory.BUSINESS_LOG_LEVEL - Represents rules business log level. This setting can be overridden by using RulesetContext per invocation. Default value is BusinessLogLevel.BASIC_BUSINESS_LOGGING.

Example

You can write the following Java snippet in your application code to obtain an instance of the lean rules engine, and also to configure the RuleEngineFactory.POLLING_FREQUENCY property for a time interval of 60000 milliseconds.

// Get an instance of factory

RuleEngineFactory factory = RuleEngineFactory.getInstance();

// Create persistence and configuration

// Assuming SDAs of Rules Composer DCs are stored at "c:\sap\rules\sdas\"

File sdaLocation = new File("c:\\sap\rules\\sdas\\");

Persistence persistence = new BuildPersistence(sdaLocation);

Properties configuration = new Properties();

configuration.setProperty(RuleEngineFactory.POLLING_FREQUENCY,"60000");

// Other properties can be configured as well

// Configure factory

factory.configure(persistence, configuration);

// Get RuleEngine instance

RuleEngine engine = factory.getRuleEngine();