Beginning Java EE 6 with GlassFish 3, Second Edition

CHAPTER 11 ■ PAGES AND COMPONENTS// orThe include directive is used to include another page (HTML, XHTML, or JSP) within the currentpage. You use this directive when you have a standard page (such as a header or a footer) you wantincluded in multiple JSPs.// orThe “JSP Standard Tag Library” section shows that JSPs can be extended through a tag library. Thetaglib directive in a JSP declares the page uses a certain tag library, uniquely identified by a URI and aprefix. In XML, it translates into a unique namespace (xmlns) at a given URI. In the following example,the http://java.sun.com/jstl/core tag library is made available to a page using the prefix c:// orScripting ElementsScripting elements are used to manipulate objects and to perform computation that affects the contentby including Java code. There are three categories of scripting elements: declarations, scriptlets, andexpressions. These can be defined following two different syntaxes.// orthis is a declaration// orthis is a scriptlet// orthis is an expressionDeclarations are used to declare Java variables or methods that are available to all other scriptingelements of the page. The declaration appears only within the translated JSP (i.e., the servlet) but not inthe output to the client. Any variable or method declared within a declaration element becomes aninstance method of the JSP and is global to the entire page. For example, you declare an ArrayList asfollows:// orList books = new ArrayList();308