Home : Tutorials : XML and Related Technologies


to the main page about the tutorial  THE XML REVOLUTION  -  TECHNOLOGIES FOR THE FUTURE WEB back up next

XLink, XPointer, and XPath

- imagine a Web without links...

Three layers:

  • XLink
    • a generalization of the HTML link concept
    • higher abstraction level (intended for general XML - not just hypertext)
    • more expressive power (multiple destinations, special behaviors, linkbases, ...)
    • uses XPointer to locate resources

  • XPointer
    • an extension of XPath suited for linking
    • specifies connection between XPath expressions and URIs

  • XPath
    • a declarative language for locating nodes and fragments in XML trees
    • used in both XPointer (for addressing), XSL (for pattern matching), XML Schema (for uniqueness and scope descriptions), and XQuery (for selection and iteration)

These technologies are standardized but not all widely implemented yet.


XQuery vs. XPointer/XPath? Reminiscent, but different goals:

  • XQuery: SQL-like database queries
  • XPointer/XPath: robust addressing into known information

back COPYRIGHT © 2000-2003 ANDERS MØLLER & MICHAEL I. SCHWARTZBACH next

Home : Tutorials : XML and Related Technologies

 

Copyright© 1998-2004 All Rights Reserved. No portion of this site may be reproduced or redistributed without prior written permission from VistaEdge Technologies

All registered trademarks appearing on this site are the property of their respective owners. Java is a trademark or registered trademark of Sun Microsystems, Inc. in the United States and other countries. This site is not connected to Sun Microsystems, Inc. and is not sponsored by Sun Microsystems, Inc.