Developing an Iterating Action
As I alluded to earlier,
a tag handler can iterate over the
element’s body until some condition is true. The evaluation of
the body may be different for each iteration, since the tag handler
can introduce a variable (used in the body) that changes its value.
An example of an iterating action is the
<ora:loop> used in this book. It can be used
to iterate over the element body once for each value in an
array, a
java.util.Vector, a
java.util.Dictionary, or a
java.util.Enumeration. Here’s an example of
how the
<ora:loop>
action
can be used:
<%@ page language="java" contentType="text/html" %>
<%@ taglib uri="/orataglib" prefix="ora" %>
<html>
<body bgcolor="white">
<%
String[] test = new String[4];
test[0] = "first";
test[1] = "second";
test[2] = "third";
test[3] = "fourth";
pageContext.setAttribute("test", test);
%>
<pre>
<ora:loop name="test" loopId="x" className="java.lang.String">
Current value: <%= x %>
</ora:loop>
</pre>
</body>
</html>Here, the <ora:loop> tag iterates over the
elements of a String array, adding the current
value to the response using a JSP expression in the action’s
body.
The
com.ora.jsp.tags.generic.LoopTag
class is the tag handler class for the
<ora:loop> action. It extends
BodyTag support and has four properties:
public class LoopTag extends BodyTagSupport {
private String name;
private String loopId;
private String className;
private String property;
...A standard property setter method is provided for each property. This ...
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