You can write  the common jsp  page contain common functionality, and in the child page  use include tag to include the common jsp page.

Using include tag you can you can do it not only for
any jsp  but also for any html pages!

inheritance is not supported in web pages  but you can use include to have some common functionality  in your pages.It is simple. you include that common jsp  page.
but , in other way , you can write  a jsp tag lib with a java class  that have some common functionality , then you can write other tag libs with their classes that this classes inherit  your common java class.

Inheritence is not supported in web pages, and including in jsp  pages really dosen't related to Inheritence concept, but including are the same and common part of jsp pages  that are included and pasred by application server as part of the main page.
I think it is better you look at Tiles. you can define your own Tiles Layout in your web app and in tiles-def extends it and also override it.

it supports inheritance.
inheritance means "code reuse" and tiles directly does it for you.
[ if you wanna use something more easier and faster to learn, use
Struts template library. it's so easly useable. ]

I didn't mean inheriting in web page!
Some one wants to use some common jsp  pages in other
jsp pages  without writing them each time and I
recommend to using <jsp:include> tag or <%@ include
file="">, the message didn't want to use tag library.