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ActionForms can be stored in either the request (preferable) or session (default) scope. This is configured in struts-config.xml. If they're in the session scope it's important to implement the form's reset method to initialize the form before each useuse (see mortar's reset method within ActionForm, SearchHelpParamsForm). ActionForms should be request based scope unless they are carried across more than one page, as is the case for our mortar ActionForm, SearchHelpParamsForm, used in all or our OAS apps which implement search help with action path /SearchHelpNavAction (see struts-config). But 99% of all other . ActionForms associated with pages that have a search help icon need to be session scope. Otherwise, ActionForms should be request scope.
By definition, every ActionForm must be a subclass of org.apache.struts.action.ActionForm.
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