Can we test XPath expression in JSP?
The <x:if> tag evaluates a test XPath expression and if it is true, it processes its body. If the test condition is false, the body is ignored.
Attribute
The <x:if> tag has the following attributes −
| Attribute | Description | Required | Default |
|---|
| select | The XPath expression to be evaluated | Yes | None |
| var | Name of the variable to store the condition's result | No | None |
| scope | Scope of the variable specified in the var attribute | No | Page |
Example
Following is an example that show the use of the <x:if> tag −
<%@ taglib prefix = "c" uri = "http://java.sun.com/jsp/jstl/core" %>
<%@ taglib prefix = "x" uri = "http://java.sun.com/jsp/jstl/xml" %>
<html>
<head>
<title>JSTL x:if Tags</title>
</head>
<body>
<h3>Books Info:</h3>
<c:set var = "xmltext">
<books>
<book>
<name>Padam History</name>
<author>ZARA</author>
<price>100</price>
</book>
<book>
<name>Great Mistry</name>
<author>NUHA</author>
<price>2000</price>
</book>
</books>
</c:set>
<x:parse xml = "${xmltext}" var = "output"/>
<x:if select = "$output//book">
Document has at least one <book> element.
</x:if>
<br />
<x:if select = "$output/books[1]/book/price > 100">
Book prices are very high
</x:if>
</body>
</html>Let us now access the above JSP, the following result will be displayed −
Books Info:
Document has at least one <book> element.
Book prices are very high
Published on 25-Mar-2019 11:18:19
