JSTL - XML <x:choose>, <x:when>, <x:otherwise> Tags

The <x:choose> tag works like a Java switch statement. With this, you can choose between a number of alternatives. Where the switch statement has the case statements, the <x:choose> tag has the <x:when> tags. In a similar way, a switch statement has the default clause to specify a default action and the <x:choose> tag has the <x:otherwise> tag as the default clause.

Attribute

The <x:choose> tag does not have any attribute.
The <x:when> tag has one attributes which is listed below.
The <x:otherwise> tag does not have any attribute.

The <x:when> tag has the following attributes −

Attribute	Description	Required	Default
select	Condition to evaluate	Yes	None

Example

<%@ 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:choose 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 = "${xmltext}" var = "output"/>
      <x:choose>
         <x:when select = "$output//book/author = 'ZARA'">
            Book is written by ZARA
         </x:when>
         
         <x:when select = "$output//book/author = 'NUHA'">
            Book is written by NUHA
         </x:when>
         
         <x:otherwise>
            Unknown author.
         </x:otherwise>
      </x:choose>

   </body>
</html>

The following result will be displayed −

Books Info:
Book is written by ZARA

jsp_standard_tag_library.htm