Why XML Based Messaging ?

Non-XML Messages:

The client and the server must agree on the size of the header section and the size of the fields it contains.

XML Messages:

An XML parser can be used to extract the content of message fields without regard to the size of the content.
No programming changes required if a data field must be lengthened.
New fields can easily be added to the header without impacting messages already stored in the queue.
No additional work is required to come up with a message format.
Payload transformations can be easily supported using XSL.

XML Message Example

<message> <header> <status>OK</status> <command>GET</command> <queueName>inbound</queueName> <processingRule>sortinvoice</processingRule> <messageId>0000001</messageId> </header> <payload> <orders> <order> <itemNumber>83726</itemNumber> <quantity>2</quantity> <price>10.00</price> </order> <order> <itemNumber>83432</itemNumber> <quantity>2</quantity> <price>10.00</price> </order> </orders> </payload> </message>

XSL Stylesheet Example:

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0"> <xsl:output omit-xml-declaration="yes"/> <xsl:template match="*"> <xsl:copy> <xsl:apply-templates> <xsl:sort order="ascending" select="itemNumber"/> </xsl:apply-templates> </xsl:copy> </xsl:template> </xsl:stylesheet>