My main concern is to indicate which parts of the libary non-developers may depend upon and which parts they must avoid using. I suppose it is true that any protected or even package components may be accessed if you hack your class just right in Java, but the presence of a protected method in a class which is not explicity intended to be subclassed would not lead me to believe that it was OK to subclass it.
in reply to Re^3: Documenting non-public OO components
in thread Documenting non-public OO components
The problem that I have with a "SUBCLASSING" heading is that, if it's present it seems to indicate that the library allows users, not just developers, to subclass that class. That wouldn't always be the case.