make two css classes be the same

make two css classes be the same

This is a general question: Is it possible to make to css classes be the
same: requiredInput = reqInp
Here is the problem: I am using Struts 2 css_xhtml template. It generates
some predefined div with css classes. On the other hand I want to use a
css frame work for managing the form style ( yaml). Luckily the structure
of the generated div and css are same as the one which is defined in the
frame work. The only issue is that the name of the css classes which
defined in css is different from the one which is generated by struts. Is
there any way which I can define I do not want to change the source of css
frame work too.
PS: I do not want to define my own template for struts and change the css
classes there.