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Overview on Struts2.





Struts2 is a popular and mature web application framework based on MVC design pattern. Struts2 is not just a new version of Struts1 but it is a complete re-write of Struts architecture.

The webwork framework initially started with Struts framework as the basis and it's goal was to offer an enhance and improved framework built on Struts to make the web development easier for the developers.

Architecture of Struts2 Framework.


FilterDispatcher routes all the requests of the framework by acting as the "front controller". With the use of the configured interceptors the request will be processed( pre-processing) before it is routed to the Action class.

Action will take control of the request and plays the role of the "model" component..Once all the interceptors are invoked  Action class takes the responsibility to execute the business logic and returns the result that is needed to be invoked.(Action class will communicate with different classes and decides the result type that is needed to be forwarded) 

 According to the result of the Action class the framework will decide which page should be rendered. This result set uses the OGNL to access the ValueStack. Once the page is completed building with values it will be sent back to the client.

View  component can be implemented with Ajax,Free Marker etc..  Finally the response will be sent to through the interceptors for the post-processing of the result.

Advantages of Struts2 Framework.


  • An advanced framework with lot of features.
  • Based on MVC Architecture.
  • Simple configuration.
  • Interceptors to reduce the cross cutting functionality- Will provide pre-processing and post-processing of the reqests and the responses
  • OGNL(Object Graph Navigational Language) - It is more powerful than JSP and is used to render the resulted value in the view layer.
  • Pluggable with different result types like Ajax, JSP,   Free Marker,Velocity etc..

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