what a documentation comment actually does?.

Answer 1

A documentation comment is referred to as a "Javadoc" and their purpose is to explain what something does. It will usually give a description of a method and what it does, it explains what each of the parameters mean as well as the return type. IDEs will display Javadoc information to developers. They simply provide an explanation.

Answer 2

After creating an instance of a class, if you want to know what that class do actually, then instead of opening the source code, you can check that in your IDE provided that you write a documentation comment. This can be viewed in a Javadoc file

Answer 3

Do they provide explanation at run time?

Answer 4

no thats not read out by the compiler so can can't available at runtime