JavaServer Faces

Using JSF with Struts and Other Application Frameworks

You may have noticed that I refer to Struts and similar frameworks as application frameworks, and to JSF as a user interface framework. I do this to emphasize that they have different objectives. An application framework’s objective is to support the development of complete applications; it’s concerned with the Big Picture. This type of framework acts as a traffic cop, routing HTTP requests to request handling code and internal view requests to response rendering code based on mappings between symbolic names and the different types of application components. An application framework doesn’t care about details, such as how the user interface is rendered, or make any distinction between user actions that only affect the user interface (e.g., asking for the next set of rows to be displayed in a table) and actions that need to be processed by backend code (e.g., processing an order on an e-commerce site). Struts, for instance, can use JSP, Velocity, XSLT, or any other presentation layer technology to render a response. The Struts servlet just routes requests to application classes that process them and then tell Struts which page to display next.

A user interface framework, on the other hand, focuses on the user interface details and isn’t concerned with how the rest of the application is implemented. It defines a detailed API for user interface components, for how user actions result in user interface events and how these events ...