JSTL Core c:when Tag
The JavaServer Pages Standard Tag Library (JSTL) encapsulates core functionality common to many JSP applications. Instead of mixing tags from numerous vendors in your JSP applications, JSTL allows you to employ a single, standard set of tags. This standardization allows you to deploy your applications on any JSP container supporting JSTL and makes it more likely that the implementation of the tags is optimized.
Below is the syntax to include JSTL Core library in your JSP for JSTL Core c:when Tag :
<%@ taglib prefix=”c” uri=”http://java.sun.com/jsp/jstl/core” %>
JSTL Core c:when Tag :Subtag of that includes its body if its condition evalutes to ‘true’.The syntax and attributes are as follows with example and ran on server to show you output:
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %> <html> <head> <title>c:when Example</title> </head> <body> <body> <c:set var="value" value="${30*2}"/> <p>Value grater than 30 is : <c:out value="${value}"/></p> <c:choose> <c:when test="${value < 30}"> Value is less than 30 </c:when> <c:when test="${value > 30}"> Value is greater 30 </c:when> <c:otherwise> Whatever we like... </c:otherwise> </c:choose> </body> </html>
JSTL Core c:when Tag output: