Changing css-class-wrapper parameter of liferay portlet at runtime

Question

As the title says - I need to change css-class-wrapper parameter at runtime, preferably in action class. I've found that Portlet interface has setCssClassWrapper method that could probably do what I want, but I can't seem to find any easy way to access current portlet object from my code. Could anyone please give me a hand with what I want to achieve.

Thanks.