Dear Xerces-J developers, At the moment, I'm the most active maintainer of Apache Xml Schema. This library, which lives inside the WS-COMMONS project, which lives inside the Web Services TLP, is a set of Java classes that form a data model for W3C XML Schema, together with code to walk DOM of schema documents and build the representation and visa versa.
XmlSchema has no capability to validate a document against a schema. Typical applications, such as Apache CXF or Apache Axis, spend a fair amount of time converting back and forth between XmlSchema representation and the ordinary DOM for schema documents, if only to pass them into the SchemaFactory to tee up validation, or into some other library. While I haven't gone spelunking in the code of Xerces yet, the existence of the validation feature strikes me as strong circumstantial evidence the existence of some representation of schema. It strikes me that two Java class libraries for W3C XML Schema inside ASF is, prima facia, one too many. So, I'm sending this email to ask if the Xerces project has interest in working on exposing a documented API to the XML Schema data model. I was am more or less on the verge of putting a significant pulse of effort into modernization and performance enhancement of XmlSchema, and if the same effort could yield a more broadly useful result, I'd like to apply it there. I am imagining a scheme where the core representation *is dom*, using subclasses of DOM interfaces to supply convenience methods for safe and comprehensible access to the abstract data model. This could radically speed up code that needs to handle schema documents as DOM and also analyze and manipulate the abstract data model of the W3C Xml Schema. But, imagination aside, I think it would be good to focus energy on a shared solution. Regards, Benson Margulies
