I think you are talking of struts' action classes, if so, there is a forum in JavaRanch about struts. First, since the action's execute method's signature and its collaborations with other struts' classes are already defined, you can not simple add the Map as a parameter, you should read about the use of struts and the struts' forms (like ValidatorForm) within jsp's.
Hopefully, if you post this in the struts forum, you can get better response.
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