SAX: two alternatives for namespaces

David Megginson david at
Wed Jul 29 14:40:09 BST 1998

Chris Hubick writes:

 > 	As far as my HXP parser goes, well, I plan on adding SAX 1
 > support as soon as I can, and had planned on namespace support
 > anyhow, so I welcome this simple addition.  Both of your proposals
 > require the parser writer to support Namespaces, and as for parsers
 > that don't - fix them :-)

Since XML 1.0 does not require namespace support, it is possible for
a parser to be XML-conformant without supporting namespaces -- in that
case, it would always set the URI part of the name to null.

This leads to another thought -- that we probably need some kind of a
hook for requesting and/or querying parser features.  This issue came
up before during the initial SAX 1.0 design.  Something like the
following might be appropriate:

  package org.xml.sax;

  public interface Parser {
    public boolean hasFeature (String featureName);
    public boolean requestFeature (String featureName, boolean status);

It is important to note that with such an approach, there would have
to be a registry of feature names in addition to the SAX interface.

Here's how you could use this interface:

  if (!parser.requestFeature("org.xml.sax.validation", true) ||
      !parser.requestFeature("org.xml.sax.namespaces", false)) {
    throw new MyException("Cannot activate validation without namespaces.");

The details remain to be worked out.

All the best,


David Megginson                 david at

xml-dev: A list for W3C XML Developers. To post, mailto:xml-dev at
Archived as:
To (un)subscribe, mailto:majordomo at the following message;
(un)subscribe xml-dev
To subscribe to the digests, mailto:majordomo at the following message;
subscribe xml-dev-digest
List coordinator, Henry Rzepa (mailto:rzepa at

More information about the Xml-dev mailing list