Help improve the logger performance

Could you add log level check first to improve performance?

`
                        String msg = r.getRule().getFullyQualifiedName() + "-{" + r.getRule().getExpression() + "}";
			if(String.valueOf(o).equals("true")){
				matchingRules.add(r.getRule());
				log.info("matched: " + msg);
			}else{
				log.info("unmatched: " + msg);
			}
`

