If you have a lot of different page actions and page parameters, or even just a lot of navigation rules, you will almost certainly want to split the declarations up over multiple files. You can define actions and parameters for a page with the view id /calc/calculator.jsp in a resource named calc/calculator.page.xml. The root element in this case is the <page> element, and the view id is implied:

<page action="#{calculator.calculate}">
    <param name="x" value="#{calculator.lhs}"/>
    <param name="y" value="#{calculator.rhs}"/>
    <param name="op" converter="#{operatorConverter}" value="#{calculator.op}"/>
</page>