You are right, checkstyle reports more missing javadoc violations on methods with @Override than the violations I find when I click the percentage. When I click the "javadoc method" violation I find many violations on @Override tags which I do not find when I click the 82.7% (which is now 84,4% by the way). I also saw a class where we did use {@inheritDoc} next to @Override and here checkstyle did not complain.
When I click the percentage I see that the main culprits (with e.g. many @Overrides but "undocumented API: 11") are classes that implement an external interface, not our own code. One is java.util.Set, the other is from our Spring security dependency. The interesting thing is that the javadoc generated by Maven does indeed NOT have javadoc for these methods! Maybe the Maven javadoc plugin cannot add the source/javadoc to the classpath?
I DID find at least one class which implements an interface of our own with 3 methods, defined in another package. The class uses @Override and I see Public undocumented API: 3, Public API: 4. Its constructor is undocumented. (Why not 4 missing?).
The rest of the violations seem to be missing Javadoc on constructors. We decided that we do not require javadoc on them because they are often very simple (we adjusted checkstyle to ignore missing constructor javadoc).
There is no need to do so, as a mechanism exists already with javadoc.
By using /** {@inheritDoc} */, it indicates that doc should be inherited and Squid does not count it as undocumented API anymore.
Closing the ticket