Log4JMarker.hasParents() will return false when the marker has parents, and true when it has none.
The javadoc in the Marker interface indicates it should function the other way around:
"Indicates whether this Marker has references to any other Markers. Return true if the Marker has parent Markers"
The code for the implementation (that I could find) demonstrates that it would function in the opposite way as it is described in that javadoc: