This page will give you a short overview of Struts Framework and its main components. After finishing reading this, continue on to the tutorial to create a simple Struts-based Web application.
The Struts Framework is a standard for developing well-architected Web applications. It has the following features:
All incoming requests are intercepted by the Struts servlet controller. The Struts Configuration file
is used by the controller to determine the routing of the flow. This flows consists of an alternation between two transitions:
|From View to Action||A user clicks on a link or submits a form on an HTML or JSP page. The controller receives the request, looks up the mapping for this request, and forwards it to an action. The action in turn calls a Model layer (Business layer) service or function.|
|From Action to View||After the call to an underlying function or service returns to the action class, the action forwards to a resource in the View layer and a page is displayed in a web browser.|
struts-config.xml, and routes to an action.
This receives all incoming requests. Its primary function is the mapping of a request URI to an action class selecting the proper application module. It's provided by the framework.
This file contains all of the routing and configuration information for the Struts application. This XML file needs to be in the WEB-INF directory of the application.
It's the developer's responsibility to create these classes. They act as bridges between user-invoked URIs and business services. Actions process a request and return an ActionForward object that identifies the next component to invoke. They're part of the Controller layer, not the Model layer.
These greatly simplify user form validation by capturing user data from the HTTP request. They act as a "firewall" between forms (Web pages) and the application (actions). These components allow the validation of user input before proceeding to an Action. If the input is invalid, a page with an error can be displayed.
The Struts Framework has no built-in support for the Model layer. Struts supports any model components:
>> Next Step: Create a Struts Application with the Exadel Studio WIDE