Описание тега actioncontext
The ActionContext is a Struts 2 container for objects needed by the application when the action is executed.
The ActionContext is a Struts 2 container for objects needed by the application when the action is executed. An action context used to access those objects during the the action execution. When Struts2 request is handled by the framework it creates an ActionContext and populate it with the framework core objects, such as request, session, application, valueStack, servlet context objects, parameters, locale, etc. The benefit of this is there's no need to worry about a user specific action context, and it could get statically from the class ActionContext which is ThreadLocal in every request.
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