The JDK API docs has references to the technotes (guides) documentation coming from the documentation comments in the source file. The references are relative links to the technotes pages within the documentation bundle. For OPEN JDK api documentation bundle build, these references would generate broken links since the OPEN JDK documentation bundle will only contain api pages and no technotes.
The javadoc tool already has an option, that the build can use, to generate absolute links for these technotes references. For that the source comment should use the @docRoot tag to reference the relative path to the technotes pages which will work for a regular api documentation build as well as OPEN JDK api documentation build.