Much more can certainly be written about XML and a number of books have done just that. This chapter just scratched the surface of XML by providing an overview of XML, highlighting important features related to XML. This chapter also discussed the related XML technologies used later in this book. To summarize this chapter: |
XML is extensible. It provides a specification for creating your own tags. XML is a metamarkup |
language. |
To be well formed, XML must essentially conform syntactically to the W3C specification, and all |
elements within the document must be children of one and only one document element. |
You have the ability to create your own tags, so make them meaningful. Because XML doesn’t |
define any tags, creating tags that make sense to other developers is crucial. |
Namespaces provide a way to group elements and attributes into one vocabulary using a unique |
name. Using the xmlns attribute, a namespace prefix is bound to a unique namespace name. |
XML schemas offer developers a rich language to describe and define the structure, cardinality, |
datatypes, and overall content of their XML documents. |
Two object models exist for processing the content in any XML document: the DOM and SAX. |
The DOM allows random access and the capability to modify, delete, and replace nodes in the XML hierarchy. SAX provides a simple, efficient way to process large XML documents. |
XSLT provides a way to transform an XML document to another format such as HTML or |
another type of XML. |
XPath is a language that permits you to address the parts of an XML document