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TABLE 6–2 EL Operators and JSP Document-Compliant Alternative Notation (Continued)
EL Operator JSP Document Notation
> gt
= ge
!= ne
You can also use EL expressions with jsp:element to generate tags dynamically rather than
hard code them. This example could be used to generate an HTML header tag with a lang
attribute:
${content.lang}
${content.body}
The name attribute identifies the generated tag’s name. The jsp:attribute tag generates the
lang attribute. The body of the jsp:attribute tag identifies the value of the lang attribute. The
jsp:body tag generates the body of the tag. The output of this example jsp:element could be
Heading in French
As shown in Table 6–1, scripting elements (described in Chapter 9, “Scripting in JSP Pages”) are
represented as XML elements when they appear in a JSP document. The only exception is a
scriptlet expression used to specify a request-time attribute value. Instead of using ,
a JSP document uses %= expr % to represent a request-time attribute value.
The three scripting elements are declarations, scriptlets, and expressions.
A jsp:declaration element declares a scripting language construct that is available to other
scripting elements. A jsp:declaration element has no attributes and its body is the
declaration itself. Its syntax is
declaration goes here
A jsp:scriptlet element contains a Java program fragment called a scriptlet. This element has
no attributes, and its body is the program fragment that constitutes the scriptlet. Its syntax is
code fragment goes here
Creating a JSP Document
The jsp:expression element inserts the value of a scripting language expression, converted
into a string, into the data stream returned to the client. A jsp:expression element has no
attributes and its body is the expression. Its syntax is
Chapter 6 • JavaServer Pages Documents 193