If unspecified, by default an ActionForm will have scope session.
The scope of an ActionForm is specified on the <action> configuration
as attribute scope.
You can find this in the Struts DTD:
The "action" element describes an ActionMapping object that is to be used
to process a request for a specific module-relative URI. The following
attributes are defined:
.....
.....
scope The context ("request" or "session") that is used to
access our ActionForm bean, if any. Optional if "name" is
specified, else not valid. [session]
.....
.....This value is initialized in the org.apache.struts.config.ActionConfig class which represents the configuration information of an element from a Struts module configuration file:
/**
* <p> Identifier of the scope ("request" or "session") within which our
* form bean is accessed, if any. </p>
*/
protected String scope = "session";