JSP - XML Data


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When you send the XML data via HTTP, it makes sense to use JSP to handle incoming and outgoing XML documents; for example, RSS documents. As an XML document is merely a bunch of text, creating one through a JSP is much easier than creating an HTML document.

Sending XML from a JSP

You can send the XML content using JSPs the same way you send HTML. The only difference is that you must set the content type of your page to text/xml. To set the content type, use the <%@page%> tag, like this −

<%@ page contentType = "text/xml" %>

Following example will show how to send XML content to the browser −

<%@ page contentType = "text/xml" %>

<books>
   <book>
      <name>Padam History</name>
      <author>ZARA</author>
      <price>100</price>
   </book>
</books>

Access the above XML using different browsers to see the document tree presentation of the above XML.

Processing XML in JSP

Before you proceed with XML processing using JSP, you will need to copy the following two XML and XPath related libraries into your <Tomcat Installation Directory>\lib

Let us put the following content in books.xml file −

<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>

Try the following main.jsp, keeping in the same directory −

<%@ 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:parse Tags</title>
   </head>

   <body>
      <h3>Books Info:</h3>
      <c:import var = "bookInfo" url="http://localhost:8080/books.xml"/>
 
      <x:parse xml = "${bookInfo}" var = "output"/>
      <b>The title of the first book is</b>: 
      <x:out select = "$output/books/book[1]/name" />
      <br>
      
      <b>The price of the second book</b>: 
      <x:out select = "$output/books/book[2]/price" />
   </body>
</html>

Access the above JSP using http://localhost:8080/main.jsp, the following result will be displayed −

Books Info:

The title of the first book is:Padam History The price of the second book: 2000

Formatting XML with JSP

Consider the following XSLT stylesheet style.xsl

<?xml version = "1.0"?>
<xsl:stylesheet xmlns:xsl = "http://www.w3.org/1999/XSL/Transform" 
   version = "1.0">
 
   <xsl:output method = "html" indent = "yes"/>
   <xsl:template match = "/">
      <html>
         <body>
            <xsl:apply-templates/>
         </body>
      </html>
   </xsl:template>
    
   <xsl:template match = "books">
      <table border = "1" width = "100%">
         <xsl:for-each select = "book">
            <tr>
               <td>
                  <i><xsl:value-of select = "name"/></i>
               </td>
               
               <td>
                  <xsl:value-of select = "author"/>
               </td>
               
               <td>
                  <xsl:value-of select = "price"/>
               </td>
            </tr>
         </xsl:for-each>
      </table>
   
   </xsl:template>
</xsl:stylesheet>

Now consider the following JSP file −

<%@ 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:transform 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>
 
      <c:import url = "http://localhost:8080/style.xsl" var = "xslt"/>
      <x:transform xml = "${xmltext}" xslt = "${xslt}"/>
   </body>
</html>

The following result will be displayed −

Books Info:

Padam History ZARA 100
Great Mistry NUHA 2000

To know more about XML processing using JSTL, you can check JSP Standard Tag Library.



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