Drools- how to find out which all rules were matched?

Question

I\'ve one .DRL file which has say 10 rules. Once I insert a fact, some rules may be matched- how do I find out which rules were matched programmatically?

Answer 1

You can use a static logger factory which will log with your favorite logger the actions from your DRL file.

For instance:

import org.drools.runtime.rule.RuleContext;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public final class DRLLogger {

private DRLLogger() {
}

protected static Logger getLogger(final RuleContext drools) {
    final String category = drools.getRule().getPackageName() + "." + drools.getRule().getName();
    final Logger logger = LoggerFactory.getLogger(category);
    return logger;
}

public static void info(final RuleContext drools, final String message, final Object... parameters) {
    final Logger logger = getLogger(drools);
    logger.info(message, parameters);
}

public static void debug(final RuleContext drools, final String message, final Object... parameters) {
    final Logger logger = getLogger(drools);
    logger.debug(message, parameters);
}

public static void error(final RuleContext drools, final String message, final Object... parameters) {
    final Logger logger = getLogger(drools);
    logger.error(message, parameters);
}

}

Then from your DRL file:

import function com.mycompany.DRLLogger.*

rule "myrule"
when
    $fact: Fact()
then
    info(drools, "Fact:{}", $fact);
end