I think you are using your custom controller.
If you use
Struts for this, their is custom tags available for all these thing.
anyway you can acheive this by,
add getter & setter for each feild in UserUpdate class.
write your jsp with one form tag with action="UpdateServlet"(url
pattern in DD of UpdateServlet).
then write text tags with name simillar to name in "UserUpdate" class feild.
due to that while submitting all feild is passed with request as parameter. you can get them by request.getParameter().
Now for displaying data You can use scriptlets in scriptlet you will get "UserUpdate" from session.(which is set in session by getting fron DB before forwarding to jsp)
now in value attribute of text tag write expression there get value from getter of that perticular feild.
actually this is not good solution, but I thing we can do this way.
You can also do this by custom tags for text feild.