Answer:
The javadoc is the type of the tool which accompanies JDK and it is utilized for producing code of the java documentation in the HTML design from the source code of the java, that basically required documentation in the predefined code format.
Most of the software development company does not use javdoc because the files of the javadoc are light in weight and it can be easily traceable by using the different types of the tools.
In case of the Public javadoc, while make changing in the API system the javadoc an easily be tracked.