In tapestry when I was creating tml pages I used to define the header like this
<html t:type="layout" title="Create Prescription"
t:sidebarTitle="Browse Medicine"
xmlns:t="http://tapestry.apache.org/schema/tapestry_5_1_0.xsd"
xmlns:p="tapestry:parameter">
Best part I found is, you could define a template t:type="layout". So every page will inherit that template page. In this way you may have multiple layout pages.
And if you define like this
<p:sidebar> only then sidebar part appears.
Now, I am doing spring mvc and would like to use those kind of features on my project. But I do not know what those features are called. Are these part of template engine like velocity?