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<HTML><HEAD><TITLE>Velocity Script Elements</TITLE></HEAD><BODY alink="#023264" bgcolor="#ffffff" leftmargin="4" link="#023264" marginheight="4" marginwidth="4" text="#000000" topmargin="4" vlink="#023264"><TABLE border="0" cellpadding="0" cellspacing="0" width="100%"><TR><TD align="left" valign="top"><A href="http://jakarta.apache.org/index.html"><IMG border="0" hspace="0" src="resources/jakarta-logo.gif" vspace="0"></A></TD><TD align="left" bgcolor="#ffffff" valign="top" width="100%"><IMG align="right" alt="" border="0" hspace="0" src="resources/header.gif" vspace="0"></TD></TR><TR><TD><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="5"></TD></TR><TR><TD background="resources/line.gif" colspan="2" height="2" width="100%"><IMG alt="" border="0" height="2" hspace="0" src="resources/line.gif" vspace="0" width="1"></TD></TR></TABLE><TABLE border="0" cellpadding="0" cellspacing="0" width="100%"><TR><TD valign="top" width="1%"></TD><TD nowrap="1" valign="top" width="14%"><BR>
<P></P>
<FONT face="arial,helvetica,sanserif" size="-1"><LI><A href="index.html">Overview</A></LI></FONT>
<FONT face="arial,helvetica,sanserif" size="-1"><LI><A href="getting-started.html">Getting Started</A></LI></FONT>
<FONT face="arial,helvetica,sanserif" size="-1"><LI><A href="install.html">Install</A></LI></FONT>
<FONT face="arial,helvetica,sanserif" size="-1"><LI><A href="design.html">Design</A></LI></FONT>
<FONT face="arial,helvetica,sanserif" size="-1"><LI><A href="script-elements.html">Script Elements</A></LI></FONT>
<FONT face="arial,helvetica,sanserif" size="-1"><LI><A href="contributors.html">Contributors</A></LI></FONT>
<FONT face="arial,helvetica,sanserif" size="-1"><LI><A href="code-standards.html">Coding Standards</A></LI></FONT>
<FONT face="arial,helvetica,sanserif" size="-1"><LI><A href="license.html">License</A></LI></FONT>
<FONT face="arial,helvetica,sanserif" size="-1"><LI><A href="todo.html">TODO</A></LI></FONT>
<P></P>
<FONT face="arial,helvetica,sanserif" size="-1"><LI><A href="user-guide.html">User's Guide</A></LI></FONT>
<FONT face="arial,helvetica,sanserif" size="-1"><LI><A href="developer-guide.html">Developer's Guide</A></LI></FONT>
</TD><TD align="left" valign="top" width="*"><TABLE border="0" cellpadding="3" cellspacing="0"><TR><TD><BR>
<DIV align="right"><TABLE border="0" cellpadding="0" cellspacing="0" width="98%"><TR><TD bgcolor="#023264" width="100%"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="5"><B>Script Elements</B></FONT></TD></TR><TR><TD><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE><TABLE border="0" cellpadding="0" cellspacing="0" width="98%"><TR><TD><FONT color="#000000" face="arial,helvetica,sanserif">
<P align="justify">
There are several different types of Script Elements within Velocity. The
overall purpose of these elements is described in the <A href="design.html">Design Document</A>.
</P>
<P align="justify">
The following elements are currently defined within Velocity and also
explained in detail below. Velocity script elements are prefixed with a #.
For example, #if, #foreach, #set.
</P>
<BLOCKQUOTE><UL>
<LI><B>Variables</B></LI>
<LI><B>Conditionals</B>:
<BLOCKQUOTE><UL>
<LI>If / Else</LI>
</UL></BLOCKQUOTE>
</LI>
<LI><B>Loops</B>:
<BLOCKQUOTE><UL>
<LI>Foreach</LI>
</UL></BLOCKQUOTE>
</LI>
<LI><B>Parse</B></LI>
<LI><B>Include</B></LI>
<LI><B>Param</B></LI>
<LI><B>Set</B></LI>
<LI><B>Comment</B></LI>
<LI><B>Stop</B></LI>
<LI><B>Macro</B></LI>
</UL></BLOCKQUOTE>
</FONT></TD></TR></TABLE></DIV><BR>
<DIV align="right"><TABLE border="0" cellpadding="0" cellspacing="0" width="98%"><TR><TD bgcolor="#023264" width="100%"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="5"><B>Variables</B></FONT></TD></TR><TR><TD><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE><TABLE border="0" cellpadding="0" cellspacing="0" width="98%"><TR><TD><FONT color="#000000" face="arial,helvetica,sanserif">
<P align="justify">
Velocity references its variables in a fashion similar to Perl (i.e. they
use a $), but takes advantage of some Java principles that template
designers will find easy to use. For example:
</P>
<P align="justify">
<DIV align="center"><TABLE border="0" cellpadding="0" cellspacing="4"><TR><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#023264" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#ffffff"><PRE>
$foo
$foo.getBar() or $foo.Bar
$data.getUser(&quot;jon&quot;) or $data.User(&quot;jon&quot;)
$data.getRequest().getServerName() or $data.Request.ServerName</PRE></TD><TD bgcolor="#023264" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></DIV>
</P>
<P align="justify">
These examples illustrate alternative uses for the same variables.
Velocity takes advantage of Java's introspection and
bean features to resolve the variable names to both objects in the Context
as well as the objects methods. It is possible to embed variables almost
anywhere in your template. These variables can be evaluated.
</P>
<P align="justify">
Everything coming to and from a variable is treated as a String object.
If there is an object that represents $foo (such as an Integer object),
then Velocity will call its .toString() method to resolve the
object into a String.
</P>
</FONT></TD></TR></TABLE></DIV><BR>
<DIV align="right"><TABLE border="0" cellpadding="0" cellspacing="0" width="98%"><TR><TD bgcolor="#023264" width="100%"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="5"><B>Conditionals</B></FONT></TD></TR><TR><TD><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE><TABLE border="0" cellpadding="0" cellspacing="0" width="98%"><TR><TD><FONT color="#000000" face="arial,helvetica,sanserif">
<DIV align="right"><TABLE border="0" cellpadding="0" cellspacing="0" width="98%"><TR><TD bgcolor="#023264" width="100%"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="5"><B>If / Else Conditionals</B></FONT></TD></TR><TR><TD><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE><TABLE border="0" cellpadding="0" cellspacing="0" width="98%"><TR><TD><FONT color="#000000" face="arial,helvetica,sanserif">
<P align="justify">
The #if statement in Velocity allows for text in the brackets to be
included in the text, on the conditional that the if statement
is true. For example:
</P>
<P align="justify">
<DIV align="center"><TABLE border="0" cellpadding="0" cellspacing="4"><TR><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#023264" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#ffffff"><PRE>
#if ($foo)
{
&lt;strong&gt;Velocity Rocks!&lt;/strong&gt;
}</PRE></TD><TD bgcolor="#023264" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></DIV>
</P>
<P align="justify">
The variable $foo is evaluated to see if it is a boolean or not null; the
content within the brackets becomes the output if the evaluation is true.
Unlike in JSP, Velocity does not force web developers to wrap HTML code
within an out.println(), or to delve into ugly workarounds to out.println().
</P>
<P align="justify">
An #else element can be used with an #if element.
</P>
<P align="justify">
<DIV align="center"><TABLE border="0" cellpadding="0" cellspacing="4"><TR><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#023264" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#ffffff"><PRE>
#if ($foo)
{
&lt;strong&gt;Velocity Rocks!&lt;/strong&gt;
}
#else
{
&lt;strong&gt;Velocity Still Rocks!&lt;/strong&gt;
}</PRE></TD><TD bgcolor="#023264" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></DIV>
</P>
<P align="justify">
In this example, if $foo is false, then the output will be
<B>Velocity Still Rocks!</B>
</P>
<P align="justify">
Note that logical operators are not yet available in Velocity.
This functionality is expected to be added soon. An example of
a logical operator is shown below.
</P>
<P align="justify">
<DIV align="center"><TABLE border="0" cellpadding="0" cellspacing="4"><TR><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#023264" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#ffffff"><PRE>
#if ($foo &amp;&amp; $bar)
{
&lt;strong&gt;Velocity Rocks!&lt;/strong&gt;
}</PRE></TD><TD bgcolor="#023264" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></DIV>
</P>
<P align="justify">
Nested #if statements can be used to emulate the functionality of #elseif.
Nesting elements work for all elements to an infinite level of nesting;
for example, a #foreach can be nested within an #if. An #elseif element
may be added in the future to simplify things.
</P>
</FONT></TD></TR></TABLE></DIV><BR>
</FONT></TD></TR></TABLE></DIV><BR>
<DIV align="right"><TABLE border="0" cellpadding="0" cellspacing="0" width="98%"><TR><TD bgcolor="#023264" width="100%"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="5"><B>Loops</B></FONT></TD></TR><TR><TD><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE><TABLE border="0" cellpadding="0" cellspacing="0" width="98%"><TR><TD><FONT color="#000000" face="arial,helvetica,sanserif">
<DIV align="right"><TABLE border="0" cellpadding="0" cellspacing="0" width="98%"><TR><TD bgcolor="#023264" width="100%"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="5"><B>Foreach Loop</B></FONT></TD></TR><TR><TD><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE><TABLE border="0" cellpadding="0" cellspacing="0" width="98%"><TR><TD><FONT color="#000000" face="arial,helvetica,sanserif">
<P align="justify">
The #foreach element allows for looping. The #foreach element is followed
by a set of brackets that enclose the target and object to be stepped
through. For example:
</P>
<P align="justify">
<DIV align="center"><TABLE border="0" cellpadding="0" cellspacing="4"><TR><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#023264" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#ffffff"><PRE>
&lt;ul&gt;
#foreach ($product in $allProducts)
{
&lt;li&gt;$product&lt;/li&gt;
}
&lt;/ul&gt;
</PRE></TD><TD bgcolor="#023264" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></DIV>
</P>
<P align="justify">
This #foreach loop causes the $allProducts list (the object) to be
looped over for all of the products (targets) in the list. Each time
through the loop, the value from $allProducts is placed into the
$product variable.
</P>
<P align="justify">
The contents of the $allProducts variable is either a Vector, a Hashtable
or an Array. The value assigned to the $product variable is a Java
Object and can be referenced from a variable as such. For example, if
$product was really a Product class in Java, its name could be retrieved
by referencing the $product.Name method (ie: Product.getName()).
</P>
</FONT></TD></TR></TABLE></DIV><BR>
</FONT></TD></TR></TABLE></DIV><BR>
<DIV align="right"><TABLE border="0" cellpadding="0" cellspacing="0" width="98%"><TR><TD bgcolor="#023264" width="100%"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="5"><B>Parse</B></FONT></TD></TR><TR><TD><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE><TABLE border="0" cellpadding="0" cellspacing="0" width="98%"><TR><TD><FONT color="#000000" face="arial,helvetica,sanserif">
<P align="justify">
The #parse script element allows a local files to be imported and parsed
through the Velocity template engine, then inserted into the location
where the #parse directive is defined. The current Context is applied to
the variables that are embedded within the template.
</P>
<P align="justify">
<DIV align="center"><TABLE border="0" cellpadding="0" cellspacing="4"><TR><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#023264" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#ffffff"><PRE>
#parse /path/to/file.vm
</PRE></TD><TD bgcolor="#023264" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></DIV>
</P>
</FONT></TD></TR></TABLE></DIV><BR>
<DIV align="right"><TABLE border="0" cellpadding="0" cellspacing="0" width="98%"><TR><TD bgcolor="#023264" width="100%"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="5"><B>Include</B></FONT></TD></TR><TR><TD><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE><TABLE border="0" cellpadding="0" cellspacing="0" width="98%"><TR><TD><FONT color="#000000" face="arial,helvetica,sanserif">
<P align="justify">
The #include script element allows the template designer to import a
local file, which is then inserted into the location where the #include
directive is defined. The contents of the file are not rendered through
the template engine.
</P>
<P align="justify">
<DIV align="center"><TABLE border="0" cellpadding="0" cellspacing="4"><TR><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#023264" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#ffffff"><PRE>
#include /path/to/file.vm
</PRE></TD><TD bgcolor="#023264" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></DIV>
</P>
</FONT></TD></TR></TABLE></DIV><BR>
<DIV align="right"><TABLE border="0" cellpadding="0" cellspacing="0" width="98%"><TR><TD bgcolor="#023264" width="100%"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="5"><B>Param</B></FONT></TD></TR><TR><TD><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE><TABLE border="0" cellpadding="0" cellspacing="0" width="98%"><TR><TD><FONT color="#000000" face="arial,helvetica,sanserif">
<P align="justify">
The #param script element allows the template designer to set items
in the context that are static and do not change over the life of the
template.
</P>
<P align="justify">
<DIV align="center"><TABLE border="0" cellpadding="0" cellspacing="4"><TR><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#023264" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#ffffff"><PRE>
#param $date = &quot;May 24, 1973&quot;
</PRE></TD><TD bgcolor="#023264" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></DIV>
</P>
<P align="justify">
The variable on the left side of the #param script element must be
prefixed with a $. This provides a consistent syntax for referencing
variables in Velocity.
</P>
</FONT></TD></TR></TABLE></DIV><BR>
<DIV align="right"><TABLE border="0" cellpadding="0" cellspacing="0" width="98%"><TR><TD bgcolor="#023264" width="100%"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="5"><B>Set</B></FONT></TD></TR><TR><TD><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE><TABLE border="0" cellpadding="0" cellspacing="0" width="98%"><TR><TD><FONT color="#000000" face="arial,helvetica,sanserif">
<P align="justify">
The #set script element allows the template designer to set variables
within the Context.
</P>
<P align="justify">
<DIV align="center"><TABLE border="0" cellpadding="0" cellspacing="4"><TR><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#023264" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#ffffff"><PRE>
#set $name = &quot;Fred&quot;
</PRE></TD><TD bgcolor="#023264" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></DIV>
</P>
<P align="justify">
When using the #set directive, the variable on the left side must be
prefixed with a $. This provides a
consistent syntax for referencing variables in Velocity.
</P>
<P align="justify">
The following script elements have not been implemented.
</P>
</FONT></TD></TR></TABLE></DIV><BR>
<DIV align="right"><TABLE border="0" cellpadding="0" cellspacing="0" width="98%"><TR><TD bgcolor="#023264" width="100%"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="5"><B>Comment</B></FONT></TD></TR><TR><TD><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE><TABLE border="0" cellpadding="0" cellspacing="0" width="98%"><TR><TD><FONT color="#000000" face="arial,helvetica,sanserif">
<P align="justify">
The ## script element allows the template designer to write comments in
templates that are not placed into the output of the template engine.
</P>
<P align="justify">
<DIV align="center"><TABLE border="0" cellpadding="0" cellspacing="4"><TR><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#023264" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#ffffff"><PRE>
## this is a comment
</PRE></TD><TD bgcolor="#023264" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></DIV>
</P>
<P align="justify">
A current problem with Velocity is that the space that comments occupy
is not removed from the template. The newlines created be these comments
will soon be removed.
</P>
</FONT></TD></TR></TABLE></DIV><BR>
<DIV align="right"><TABLE border="0" cellpadding="0" cellspacing="0" width="98%"><TR><TD bgcolor="#023264" width="100%"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="5"><B>Stop</B></FONT></TD></TR><TR><TD><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE><TABLE border="0" cellpadding="0" cellspacing="0" width="98%"><TR><TD><FONT color="#000000" face="arial,helvetica,sanserif">
<P align="justify">
The #stop script element allows the template designer to stop the execution
of the template engine and return. This is useful for debugging purposes.
</P>
<P align="justify">
<DIV align="center"><TABLE border="0" cellpadding="0" cellspacing="4"><TR><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#023264" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#ffffff"><PRE>
#stop
</PRE></TD><TD bgcolor="#023264" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></DIV>
</P>
</FONT></TD></TR></TABLE></DIV><BR>
<DIV align="right"><TABLE border="0" cellpadding="0" cellspacing="0" width="98%"><TR><TD bgcolor="#023264" width="100%"><FONT color="#ffffff" face="arial,helvetica,sanserif" size="+1"><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="5"><B>Macro</B></FONT></TD></TR><TR><TD><IMG border="0" height="5" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE><TABLE border="0" cellpadding="0" cellspacing="0" width="98%"><TR><TD><FONT color="#000000" face="arial,helvetica,sanserif">
<P align="justify">
With the #macro script element, the template designer can define a
time-saving macro.
</P>
<P align="justify">
<DIV align="center"><TABLE border="0" cellpadding="0" cellspacing="4"><TR><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#023264" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#ffffff"><PRE>
#macro (row $content) &lt;tr&gt;&lt;td&gt;$content&lt;/td&gt;&lt;/tr&gt; #end
</PRE></TD><TD bgcolor="#023264" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></DIV>
</P>
<P align="justify">
This establishes a macro called &quot;row&quot;, which uses HTML tags to
put content into its own table data cell in an HTML table. Having
defined the #row macro, the template designer can now call the #row
macro by name.
</P>
<P align="justify">
<DIV align="center"><TABLE border="0" cellpadding="0" cellspacing="4"><TR><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#023264" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#ffffff"><PRE>
&lt;table&gt;
#foreach ($element in $list)
#row ($element)
#end
&lt;/table&gt;
</PRE></TD><TD bgcolor="#023264" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR><TR><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD><TD bgcolor="#023264" height="1" width="1"><IMG border="0" height="1" hspace="0" src="resources/void.gif" vspace="0" width="1"></TD></TR></TABLE></DIV>
</P>
<P align="justify">
Here a newly created #row macro is nested inside a #foreach
statement. As the #foreach statement loops through each $element
target in the $list object, the #row macro will take the value of
$element and put it into its table data cell.
</P>
</FONT></TD></TR></TABLE></DIV><BR>
</TD></TR></TABLE></TD></TR></TABLE><BR><TABLE border="0" cellpadding="0" cellspacing="0" width="100%"><TR><TD bgcolor="#023264"><IMG height="1" src="resources/resources.gif" width="1"></TD></TR><TR><TD align="center"><FONT color="#023264" face="arial,helvetica,sanserif" size="-1"><I>
Copyright &copy; 2000 The Apache Software Foundation.
All Rights Reserved.
</I></FONT></TD></TR></TABLE></BODY></HTML>