While we can not validate all properties since all of environment properties and JVM are available in our configuration, we could at least make sure that those having an "hibernate.search." prefix are valid.

Validity if the property is also a bit tricky to define, as we allow independent property definitions for each module, and some are defined by third party extensions.

So the idea is to track which specific keys are being actually "hit" by some cfg.getProperty( "key" ) .. any property which has an unexpected key name would not be hit. For these we trigger a warning being logged.