Beginning Java EE 6 with GlassFish 3, Second Edition

CHAPTER 11 ■ PAGES AND COMPONENTSAll these implicit objects are actual objects with interfaces, and, once you know what they are (referto the specification), you can access their attributes with EL. For example, #{view.locale} will get thelocale of the current view (en_US, pt_PT, etc.). If you store a book object in the session scope, you couldaccess it like this: #{sessionScope.book}. You can even use a richer algorithm to display all the HTTPheaders and their values as follows:Listing 11-15. A Page Displaying the HTTP Headers Using the headerValues Implicit ObjectheaderValues =If you execute this page, you will get a page that shows all the HTTP headers.SummaryThis chapter explained the different ways of creating web pages using static languages such asHTML, XHTML, or CSS and dynamic ones such as JavaScript or server-side technologies. To createdynamic web interfaces with Java EE 6, you can choose from several specifications. JSP 2.2, EL 2.2, andJSTL 1.2 are specifications that were created with servlets in mind. Pages consist of HTML data and Javacode compiled into servlets that send back a response to a given request.Even though JSP can serve as a JSF PDL, it is better to use Facelets to achieve the power of the JSFcomponent-based architecture and rich life cycle. JSF provides a set of standard widgets (buttons,hyperlinks, check boxes, etc.) and a new model for creating your own widgets (composite components).JSF 2.0 also provides a new resource-handling mechanism, allowing you to easily version and localizeyour external resources.JSF 2.0 uses a rich UI component architecture, and its components can be converted and validated,and can interact with managed beans. This will be the topic of the next chapter.343