There are multiple ways to add comment in JSP page, as it is java view technology which primarily focuses on view part of web application which includes html majorly and being java technology it can contain java code as well. So one needs to understand how to use proper comments in jsp.
There are 3 types of comments we can use in JSP page:
Java comment (which can used inside scriplets)
To see the source code of java class translated by container of JSP page:
Netbeans: Right-click on page and select view servlet