Traversing the XPath

What is XPath: XPath is an expression language that points to data represented in an XML document. XPath can point to one or more nodes in an XML document and perform basic arithmetic operations. XPath is a very rich language and selection of nodes can be based on any condition including arithmetic comparisons.

Why is XPath important: XPath is used in many other very important specifications. For example, XML Styling Language Transformation (XSLT), and XPointer (XML Pointer). XML Styling language Transformation can be used to generate one XML from another. It can also be used to generate human readable XHTML documents from an XML document. XPointer itself is used in specifications like XLink. (Which I discussed in earlier posts)

What's new in Java 7 - Project Coin

What's new in Java 7: Well, its a major version upgrade, there needs to be a lot of things coming up. Of course the most noticeable feature set for a java programmer would be the language level change, i.e. Project Coin. Although the changes are not as major as generics (that came with version 5, which was the time they dropped the "1." from the version number.) or annotations (also came with the same version). But, I guess they are at least as good as auto-boxing.

What is Project Coin: Project Coin or JSR334 is the common JSR that embraces all language level changes that comes in Java 7. I will talk about its features one by one.

XPointer Primer

In my earlier post on XLink, I have explained that XLink uses XPointer to point to nodes in the XML. So, I decided to write an article on XPointer.

What is XPointer: XPointer is a specification that allows pointing to nodes in an XML. XLink in dependent on XPointer specification, and so is XPath specification, which is used heavily in XSLT(XML Styling Langage Transformation). XPointer is compact and non-XML, and is designed to be able to fit into a URL (in the fragment part).

 

X-Link Extended Links

What is X-Link: X-Link is a specification that allows to link between different XML tags. It is very much like an anchor in HTML, you know the regular <a href="..."></a>. However, X-Link is much more versatile and powerful as we will see.

Unlike HTML anchor tag (which is defined to be able to display a visible link), the use of X-Link is not that limited, and depends on where it is used (Is not all other XML based specifications). As such X-Link specification is not designed to be used on its own, there must be other specifications that define specific rules to use it. It is pretty much like XML itself. XML can be used in many ways, and other standards and specifications define what some XML content means. SOAP and WSDL are two specification that use XML specification. Similarly, Extensible Business Reporting Language is a specification that uses X-Link.