Why do you inherit actionsupport?

The action in Struts2 can inherit Actionsupport, or you can not inherit actionsupport.
If you do not inherit actionsupport, you only need to have one method, return a string, and remember that, in the case of inheriting actionsupport, there must be no parameter constructor.
The benefits of inheriting Actionsupport are:
1, can use Struts preset return string, such as Success,input and so on.
2, rewrite the method, more convenient to achieve verification, internationalization and other functions.
3, with the function of struts tightly, convenient development.

Why do you inherit actionsupport?