MACROMEDIA COLDFUSION MX 61-DEVELOPING COLDFUSION MX, Develop Manual

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Using JSP tags and tag libraries 739
Using JSP tags and tag libraries
You can use JSP tags from any JSP tag library. For example, you can use any of the custom tags in
the open-source Apache Jakarta Project Taglibs project tag libraries, located at http://
jakarta.apache.org/taglibs/index.html. This project consists of a number of individual JSP custom
tag libraries for purposes ranging from JNDI access to generating random text strings.
Using a JSP tag in a ColdFusion page
JSP pages use a standard set of tags, such as
jsp:forward
and
jsp:include
. You can also import
custom JSP tag libraries into a JSP application. You can use both the standard JSP tags and
custom JSP tags in ColdFusion pages, as the following sections describe.
Standard JSP tags and ColdFusion
ColdFusion tags provide equivalent features to most standard JSP tags. For example, the
cfapplet
tag provides the same service as the
jsp:plugin
tag, and
cfobject
tag lets you use
JavaBeans, as does the
jsp:usebean
tag. Similarly, you do not use the
jsp:getproperty
tag
because ColdFusion automatically gets properties when you reference them. Therefore,
ColdFusion does not support the use of standard JSP tags directly.
However, two standard JSP tags provide functionality that is useful in ColdFusion pages: the
forward
and
include
tags invoke JSP pages and Java servlets. The PageContext object described
in “About GetPageContext and the PageContext object.” on page 738 has
forward
and
include
methods that provide the same operations. For more information about using these methods see
“Accessing a JSP page or servlet from a ColdFusion page” on page 740 .
Using custom JSP tags in a ColdFusion page
Follow these steps to use a custom JSP tag on a ColdFusion page:
To use a custom tag:
1
Put the tag library, consisting of the taglibname .jar file, and the taglibname .tld file, if one is
supplied, in the web_root /WEB-INF/lib directory. The JSP custom tag library must be in this
directory for you to use the
cfimport
tag.
2
In the ColdFusion page that uses a JSP tag from the tag library, specify the tag library name in
a
cfimport
tag; for example:
<cfimport taglib="/WEB-INF/lib/random.jar" prefix="random">
If the TLD file is not included in the JAR file, use the .tld suffix in place of the .jar suffix.
Note: The cfimport tag must be on the page that uses the imported tag. You cannot put the
cfimport tag in Application.cfm.
3
Use the custom tag using the form prefix : tagName ; for example:
<random:number id="myNum" range="000000-999999" />
Note: You cannot use the cfsavecontent tag to suppress output of a custom JSP tag.