You can always get the value of your checkbox in your controller using req.getParameter(<param name>) if this function returns "On" that means that checkbox is selected. Check www.w3schools.com for further information on these controls.
Thanks & Regards, SK
SCJP 5.0, DB2 - 800, DB2 - 803, SCDJWS (On the way)
That being said, I also noticed you mentioned "java Action class" and when I see folks say Action I think a framework might be involved. If this is true, while my suggestion above is still valid, there may be a different/easier/harder way to do it using the framework. You'll just need to let us know.