ActionContext, ValueStack, and Stack Context cannot be clearly divided...

ActionContext
One Action call creates an ActionContext.
Call: ActionContext context = ActionContext. getContext ()

ValueStack
Implemented by the OGNL framework
You can simply think of it as a List

The items in ValueStack are first imported and then output, and many elements without IDs are used up and then rolled back.

 

Stack Object

Objects put into the stack, usually action

Stack Context (map)

Some naming objects are provided, which are irrelevant to the root object. to access these objects, you must use the # prefix to name them. For example, there are parameters objects, request objects, session objects, and application objects.