Using a JS and JSP function in submit form

I have this JS function

The function is returns "/outstanding-appeals-nonstop16/insertForm"

function access() { <% String insert = request.getParameter("insert"); %> `
    var insert2 = "<%=insert%>";
    return ("/outstanding-appeals-nonstop16/" + insert2 + "/");
}

In my form I have

<form:form commandName = "aNewForm" action =  "javascript:access()"  method ="POST">
</form:form>

insertForm is a method in the controller. If I put action = "/outstanding-appeals-nonstop16/insertForm" I get the result I am looking for. But I think the action is just calling the JS function instead of the value given from the JS function.