March 2002

• [March 29, 2002] "Versioning Extensions to WebDAV. (Web Distributed Authoring and Versioning)." By Geoffrey Clemm (Rational Software), Jim Amsden (IBM), Tim Ellison (IBM), Christopher Kaler (Microsoft), and One Microsoft Way, Redmond, WA 90852 Jim Whitehead (UC Santa Cruz, Department of Computer Science). IETF Network Working Group. Request for Comments: 3253. March 2002. "This document specifies a set of methods, headers, and resource types that define the WebDAV (Web Distributed Authoring and Versioning) versioning extensions to the HTTP/1.1 protocol. WebDAV versioning will minimize the complexity of clients that are capable of interoperating with a variety of versioning repository managers, to facilitate widespread deployment of applications capable of utilizing the WebDAV Versioning services. WebDAV versioning includes automatic versioning for versioning-unaware clients, version history management, workspace management, baseline management, activity management, and URL namespace versioning... The benefits of versioning in the context of the worldwide web include: (1) A resource has an explicit history and a persistent identity across the various states it has had during the course of that history. It allows browsing through past and alternative versions of a resource. Frequently the modification and authorship history of a resource is critical information in itself. (2) Resource states (versions) are given stable names that can support externally stored links for annotation and link server support. Both annotation and link servers frequently need to store stable references to portions of resources that are not under their direct control. By providing stable states of resources, version control systems allow not only stable pointers into those resources, but also well defined methods to determine the relationships of those states of a resource... WebDAV Versioning defines both basic and advanced versioning functionality. Basic versioning allows users to: (1) Put a resource under version control (2) Determine whether a resource is under version control (3) Determine whether a resource update will automatically be captured (4) Create and access distinct versions of a resource. Advanced versioning provides additional functionality for parallel development and configuration management of sets of web resources... To maximize interoperability and the use of existing protocol functionality, versioning support is designed as extensions to the WebDAV protocol (RFC2518), which itself is an extension to the HTTP protocol (RFC2616). All method marshalling and postconditions defined by RFC 2518 and RFC 2616 continue to hold, to ensure that versioning unaware clients can interoperate successfully with versioning servers. Although the versioning extensions are designed to be orthogonal to most aspects of the WebDAV and HTTP protocols, a clarification to RFC 2518 is required for effective interoperable versioning... When an XML element type in the DAV: namespace is referenced in this document outside of the context of an XML fragment, the string DAV: will be prefixed to the element type. When a method is defined in this document, a list of preconditions and postconditions will be defined for that method. If the semantics of an existing method is being extended, a list of additional preconditions and postconditions will be defined. A precondition or postcondition is prefixed by a parenthesized XML element type that identifies that precondition or postcondition..." Other documents on versioning are referenced with deliverables from the IETF Delta-V Working Group. See "WEBDAV (Extensions for Distributed Authoring and Versioning on the World Wide Web."

• [March 29, 2002] "WebDAV." By Rael Dornfest. Emerging Technology Brief from O'Reilly Research. March 26, 2002. "WebDAV (Web-based Distributed Authoring and Versioning, also called DAV) is a set of extensions to HTTP/1.1 (HyperText Transfer Protocol, the protocol spoken by Web browsers and servers) allowing you to edit documents on a remote Web server. DAV provides support for: (1) Editing: creating, updating, deleting (2) Properties: title, author, publication date, etc. (3) Collections: analogous to a file system's directory or desktop folder (4) Locking: prevents the confusion and data corruption caused by two or more people editing the same content at the same time WebDAV is platform independent, both in terms of client and server. This means that Macintosh, *nix, and Windows users can collaborate on Web content without all the usual conversion problems. Furthermore, it doesn't matter whether your documents are hosted on an Apache or Microsoft IIS server... WebDAV is an open standard, published by the IETF (the Internet Engineering Task Force) (RFC 2518). A completely open process, all it takes to join the WebDAV working group is subscription to and participation on a mailing list. Involved in the original development of WebDAV were representatives of companies the likes of Microsoft, Netscape, Novell, and Xerox. WebDAV support appears in a veritable cornucopia of Open Source projects, programming languages, commercial products, and services. WebDAV is baked right into the Windows (Web Folders) and Mac OS X operating systems as folders, that for all intents and purposes appear to be on your local machine, but are actually network connections to a remote server. The Zope Open Source content management system affords editing of content from well-known authoring tools like Adobe GoLive 5. DAV modules exist for most programming languages; they are either native or there are plug-ins for about every Web server in existence..." See "WEBDAV (Extensions for Distributed Authoring and Versioning on the World Wide Web."

• [March 29, 2002] "Information Modelling for System Specification Representation and Data Exchange." By Erik Herzog and Anders Törne (RTSLAB, Department of Computer and Information Science, Linköpings Universitet, Sweden). Pages 136-143 (with 20 references) in Proceedings of Eighth Annual IEEE International Conference and Workshop on the Engineering of Computer Based Systems (ECBS '01, April 17-20, 2001, Washington DC, USA). Abstract. "This paper presents the emerging STEP standard AP-233 with focus on the non-functional requirements that have guided the development process. The purpose of the paper is to present and motivate the modelling assumptions and approach selected for the AP-233 information model, and to present how the EXPRESS information modelling language have been used. Although the paper is focused on AP-233 and the constraints imposed by the STEP framework it is believed the structures and requirements presented are general and applicable to other systems engineering information-modelling projects. (Standard for the Exchange of Product model data -- ISO 10303) is an attempt to reduce the cost for implementing tool data exchange capabilities through the definition of a standardised information model for the systems engineering domain. By combining the information model with other STEP elements it is possible to automate significant parts of the interface development process, thus reducing effort and cost for enabling tool data exchange capabilities... The selection of STEP as framework can be questioned in the light of the tremendous interest in the XML standard. However, the choice of framework shall not be over dramatised. An information model developed in express can easily be translated to XML. A standard mapping from EXPRESS to XML is defined in ISO/PDTS 10303-28:2000 Product data representation and exchange: Implementation methods: XML representation of EXPRESS schemas and data.. The end result, a standardised information model, regardless of language used, is the lasting value of the activity... EXPRESS supports the definition of (1) Entities: the basic object of the information model, i.e., a representation of an element within the scope of the information model. (2) Inheritance relationships: The specialisation/generalisation relationship between entities. Inheritance in EXPRESS can take one of the following forms: 'One of', an instantiation of a supertype is exactly one of the subtypes, 'And', an instantiation of a supertype is the union of all subtypes, or 'AndOr', an instantiation of a supertype is a variable subset of the union of all subtypes. (3) Basic types: an elementary type that can not be further subdivided, e.g., an integer or a string. (4) Properties: entities have properties. A property is a special aspect of an entity. From an information modelling view point a property may be expressed using combinations of the constructs below. (5) Attributes: representing an aspect of an entity. Within AP-233 the term attribute is used to refer to aspects represented using basic types. (6) Relationships: Defining associations between two constructs in an information model. Within AP-233 a relationship is always defined between entities. (7) Cardinality constraints: a constraint on relationships and attributes defining the number of instances of one construct that can be associated by another construct. Constraints may be closed or open-ended. (8) Textual constraints: EXPRESS supports the definition of formal constraints on entities, relationships, attributes and other modelling constructs. The expressive power is comparable to the combination of UML and OCL... EXPRESS offer two mechanisms for defining the semantics and ensuring integrity of an information model. As in any other information modelling language semantics may be defined explicitly be using specific entities with for each concept supported. The second approach is to define fewer entities and use formal rules to define valid attribute and relationship value combinations. In AP-233 the preferred modelling approach is to explicitly define entities for each concept supported and to minimise the use of rules for defining the semantics of the model. This approach result in more entities defined, but improves model transparency and readability. [...] This paper has presented the information modelling approach selected for the development of AP-233. The main contribution is an outline of the basic modelling assumptions, how the information modelling language, EXPRESS, has been used in AP-233. Maintaining specification semantics has been the high priority in information model construction. The current revision of the information model is extensive as it captures the semantics as well as syntax of specifications. We believe this to be a crucial prerequisite for the successful standardisation and industrial acceptance of data exchange information models in general and for AP-233 in particular. At the time of writing the latest draft of AP-233 is being validated through the implementation of tool data exchange interfaces. The lessons learned from this exercise will be incorporated and the model will harmonised with the new modular structure in STEP..." See: (1) other STEP/EXPRESS documentation from the SEDRES [System Engineering Data Representation and Exchange Standardisation] Project; (2) STEP/EXPRESS and XML; (3) STEPml XML Specifications. [cache]

• [March 29, 2002] "DISARM: Document Information Set Articulated Reference Model." By Rick Jelliffe. Discussion Draft. February 24, 2002. ISO/IEC JTC1/SC34 Document #292. "This note proposes an ISO standard 'Document Information Set Articulated Reference Model' be developed, to provide the basis for ISO DSDL and for renewing ISO 8879 SGML... The utility of DISARM might include that it can provide an attractive way to allow a top-down re-specification of SGML in a future ISO 8879. It would might also provide some help for DSDL." Motivation: "Since 1986, there have been four notable streams in markup languages: (1) ISO 8879 SGML, extended by the General Facilities, Architectural Forms Definitions Requirements (ADFR), Lexical Types Definition Requirements (LTDR), Formal System Identifiers (FSI), Annexes J to L, augmented with OASIS Catalogs. A parser implementation of mature SGML in Open Source is James Clark's SP. (2) W3C HTML, in various versions, with dialects including ASP, JSP, PHP, and Blogger. A parser implementation for mature HTML in Open Source is Dave Ragget's Tidy. (3) W3C XML, extended by Namespaces, XBase, XInclude. Widespread implementations of parsers use the mature SAX API. (4) The current ISO DSDL project, informed by RELAX Namespaces, RELAX NG, W3C XML Schemas, Schematron. The Xerces XNI API is a recent attempt to cope with post-processing XML, for uses such as validation and creating typed information sets. In all these cases, the natural increase in complexity of evolving standards has made it difficult to understand the processing order and operation. ISO 8879 has been widely criticized for not being amenable to simple grammatical analysis ('not using "computer science concepts"'), yet the same problems are experienced even with overtly layered specifications such as the XML family, due to this entropy. These problems would be reduced by introducing a reference model which was neutral with regard to each of the four main streams, but allowed clear and diagrammatic exposition of the stages of parsing and processing a marked-up document incrementally from bits to a terminal information set... The reference model uses UML terminology and diagrams at the top-level only. If desired, specific graphical stereotypes could be created, as allowed by UML. It models the kinds of markup processing of interest as a chain of components, one connected to the next, each of which implements a common event-passing interface. Different markup languages and SGML features can be modeled using particular chains of components..." Cf. also the DSDL list. References: see "Document Schema Definition Language (DSDL)." [cache]

• [March 29, 2002] "IBM Xperanto Demo." March 2002. ['Get a sneak preview of IBM's exciting new standards-based information integration technologies! Xperanto represents IBM's work combining emerging XML and XQuery standards with the power of data integration. This interactive demo shows how a newly-merged bank and financial services company uses XQuery as a single interface to deliver a single view of data to a customer and to a sales representative.] "The IBM Xperanto demo is a technology preview that illustrates how IBM is advancing the state of integration technology with Xperanto, combining XML and the emerging standard, XQuery, with the power of data integration across relational databases, XML documents, flat files, spreadsheets, Web services, and more. The demo financial scenario page of the demo describes common situations for which this technology is a solution. The technology details pages display the queries and demonstrate how IBM integrates query, federation, Web services, and text search technologies using XQuery, the common query language for accessing XML. Using IBM's Xperanto, you can simplify data integration tasks for the new breed of Web and XML applications that require delivering a complete enterprise view of customers, partners, and services to improve customer service, supply chain management, and enterprise decision-making..." See also (1) "Meet the Experts: Jim Kleewein talks about the Xperanto Technology Demo"; (2) "Xperanto, Bridging Relational Technology and XML"; this second article describes the design and implementation of an XML middleware system to create XML views of relational data, query XML views and store/query XML documents using a relational database system. See "XML and Query Languages."

• [March 29, 2002] "XUL Tutorial." By Neil Deakin. March 18, 2002 or later. "This tutorial describes XUL, the XML-based User-interface Language. This language was created for the Mozilla application and is used to define its user interface. The XUL implementation and the Mozilla browser are ever-changing. Some of the information contained within this tutorial may be outdated. The default skin has changed since some of the screen shots were taken, so the images may not match up to recent builds... XUL (pronounced zool and it rhymes with cool) was created to make development of the Mozilla browser easier and faster. It is an XML language so all features available to XML are also available to XUL. Most applications need to be developed using features of a specific platform making building cross-platform software time-consuming and costly. This may not be important for some, but when you consider that users may want to use an application on other devices such as handheld devices or set-top boxes, it is quite useful to allow users to. A number of cross-platform solutions have been developed in the past. Java, for example, has portability as a main selling point. XUL is one such language designed specifically for building portable user interfaces. It takes a long time to build an application even for only one platform. The time required to compile and debug can be lengthy. With XUL, an interface can be implemented and modified quicky and easily. XUL has all the advantages of other XML languages. For example XHTML or other XML languages such as MathML or SVG can be inserted within it. Also, XUL is easily localizable, which means that it can be translated into other languages easily. Style sheets can be applied to modify the appearance of the user interface (much like the skins or themes feature in WinAmp or some window managers)..." See also the "Mozilla XUL and Script Reference." Local references: "Extensible User Interface Language (XUL)."

• [March 29, 2002] "Template Languages in XSLT." By Jason Diamond. From XML.com. March 27, 2002. ['Our main feature this week on XML.com takes up where Eric van der Vlist left off in his July 2000 article on "Style Free Stylesheets." Jason Diamond follows up on Eric's observations that XSLT doesn't encourage a good separation between content and presentation, and pursues the development of a higher-level templating language aimed at creating a cleaner XSLT template infrastructure. Jason shows how his example-based template language, implemented in XSLT itself, is easier for everyday use, especially where non-technical colleagues are involved.'] "Despite its simplicity and its original purpose, XSLT is an extremely rich and powerful programming language. Just about anything that can be done with XML can be implemented in XSLT -- all it really takes is a little bit of creativity and a whole lot of pointy brackets. One of the most common uses of XSLT is to transform XML content into something more suitable for viewing. This separation between content and presentation seems to be the most often cited advantage for many XML advocates. XSLT was designed specifically for this task It could be argued, however, that, XSLT fails miserably at separating these two layers. Traversing source documents with any sort of XPath or XSLT instructions like xsl:for-each and xsl:apply-templates in your style sheets is like opening a connection to a database and performing a query in the middle of an ASP or JSP page. Good programmers don't do this because it breaks the separation between the presentation and data tiers in their applications. Thinking about it from an altogether different perspective, having literal result elements interspersed with XSLT instructions in your transforms is like generating HTML by concatenating strings and then printing them to your output (as is often done when implementing servlets). Most designers can't work in an environment like that. Even if they can, they shouldn't have to concern themselves with all the logic of extracting and manipulating the data they're trying to present... Getting XSLT to process your custom templates isn't as easy as I would like it to be, but once the initial framework is created, adding new instructions and variables is relatively painless. Creating a prototype with XSLT is certainly the quickest way to go as you can easily add new instructions when your template designer needs them. I've personally used the techniques described in this article to prototype a template language with close to 200 instructions. The templates that utilized those instructions were still preferable to hardcoded XPath/XSLT, and it was possible to re-implement the template language processor in a more efficient language (a subject for another article) once the design was finalized without requiring any changes to the templates themselves..." For related resources, see "Extensible Stylesheet Language (XSL/XSLT)."

• [March 29, 2002] "SVG Tips and Tricks, Part One." By Antoine Quint. From XML.com. March 27, 2002. ['Antoine Quint has been busy in his labs, brewing up content for his SVG column. This month, Antoine packs a whole bunch of cool tricks into creating an animated data-exploration widget.'] "The previous installments of this column discussed the two major techniques at the core of interactive SVG: SVG animation and DOM scripting. We saw how the powerful declarative syntax adapted from SMIL brought life to SVG documents, and how SVG's DOM goes further than XML's core DOM. This month's column, rather than a focused exploration of a particular SVG topic, will examine a few helpful tips and tricks. First, I'll introduce the viewBox attribute for zooming purposes, then explain how to use the SMIL DOM interfaces for remote animation startups, and, last, I'll conclude with a closer look at DOM Events. At the end, you will understand the tricks used and abused in the interactive tree map companion demo. Before we turn to specifics, I should tell you a bit about the demo. The SVG code of the tree map was actually generated by XSLT from an XML file. The aim was to construct a mechanism to represent an XML file's hierarchy in SVG and be able to browse it in an interactive way. So we are dealing with a nice little tree app here. If you look at the SVG code you'll see that there is still a strong depth structure here too. The idea is that each time we met a node in the XML file, we would create a rectangle and a text label. If the node had a child, then we would process the subtree according to the same rule..." Note also in this connection the title SVG Essentials: Producing Scalable Vector Graphics with XML, by J. David Eisenberg (O'Reilly, First Edition: February 2002; ISBN: 0-596-00223-8): "Eisenberg begins with basics needed to create simple line drawings and then moves through more complicated features like filters, transformations, and integration with Java, Perl, and XSLT. Unlike GIFs, JPEGs or PNGs (which are bitmapped), SVG images are both resolution- and device-independent, so that they can scale up or down to fit proportionally into any size display or any Internet device -- from PDAs to large office monitors and high-resolution printers. Smaller than bitmapped files and faster to download, SVG images can be rendered with different CSS styles for each environment. They work well across a range of available bandwidths." See: "W3C Scalable Vector Graphics (SVG)."

• [March 29, 2002] "Basic Training. [XML Q&A.]" By John E. Simpson. From XML.com. March 27, 2002. ['Could you describe XML in simple, concise language? That's the challenge John Simpson has taken up this week in his XML Q&A column. The result is a gentle introduction to XML that will prove useful for beginners.'] "In this month's column, we celebrate XML's fourth year (belatedly) by way of a deceptively simple question... Is it even possible to explain XML in simple English... XML (an acronym for Extensible Markup Language) is a set of rules, published by the W3C (World Wide Web Consortium), for building new languages..."

• [March 29, 2002] "W3C XML Schema Needs You." By Leigh Dodds. From XML.com. March 27, 2002. ['One of the consequences of complexity in an open specification is a decreased likelihood of interoperability in implementation. XML developers have been bumping into this problem with the W3C XML Schema language recently. Leigh Dodds covers these problems, and a call for developers to aid the progress of greater interoperability.] "The W3C XML Schema (XSD) specifications have drawn fire again recently, with a number of concerns being aired about an apparent lack of interoperability between implementations. Jonathan Robie, a member of the Schema Working Group, has issued a rallying cry for developers to unite and help push for interoperability... There was a resurgence of the 'XML Schema is too complex' debate on XML-DEV last week. While this is an oft debated topic, the issues have had a slightly different slant this time around with claims that XSD is so complex that it's proving extremely difficult to implement... A few constructive suggestions were circulated during the discussion, some more radical than others. Rob Griffin suggested producing a list of standard error messages for validators, which ought to help achieve some level of consistency across implementations, as well as clarifying the circumstances in which each error should arise. Andrew Watt recommended the addition of a use case document that would provide an additional means of tackling the specifications. Watt pointed to the XML Query documents as a good exemplar. Rick Jelliffe's suggestion to modularize XML Schema was the most radical. Jelliffe suggested that instead of a rewrite the schema specifications should be split into eight small sections which '...would allow greater modularity, let readers and implementers concentrate and advertise conformance on different parts, and fit in with ISO DSDL, for users who, say, want to use RELAX NG with XML Schemas primitive datatypes'. Jelliffe also commented that rather than criticizing XML Schema, the important first question should be to consider which schema language or combination of languages is most suited to a particular application domain. Jelliffe offered a prediction that document oriented systems will likely settle on DSDL, while database oriented applications will find XML Schemas most suitable..." See: (1) "Document Schema Definition Language (DSDL)"; and (2) "XML Schemas."

• [March 29, 2002] "Thinking XML: Basic XML and RDF Techniques for Knowledge Management. Part 5: Defining RDF and DAML+OIL schemata." By Uche Ogbuji (Principal consultant, Fourthought, Inc.). From IBM developerWorks, XML Zone. March 2002. ['Uche Ogbuji moves on to define RDF and DAML+OIL schemata for the issue tracker application, continuing the discussion of modeling as he goes along.'] "In my last installment of this column, I discussed how XML knowledge management systems such as RDF shed a different light on age-old problems of data design and modeling. This was done toward the goal of nailing down a schema for the issue tracker package that I have been using to illustrate the use of RDF in association with XML applications. Now I'll complete the definition of the issue tracker schema, in RDFS and DAML+OIL form. Again, familiarity with RDF, RDFS, and DAML+OIL are required. Since the last installment, I have published an introduction to DAML+OIL with my colleague Roxane Ouellet, so you no longer have to slog through the dense specifications to get a handle on it. [...] Generally, even if you wish to apply constraints in the loose way discussed in the last installment of this column, you should have a schema of some sort, for documentation if nothing else. RDFS is still the simplest and most pervasive choice, but DAML+OIL has many things to recommend it: not just the additional features, but the cleaner core semantics as well. Now that we have a schema for the issue tracker, we'll move on to improving the way we construct our queries: We'll look at Versa, an open query language for RDF that will make all the query code we've presented simpler and faster..." Also available in PDF format.

• [March 28, 2002] "Encoded Archival Context (EAC) - Recent Developments." By Per-Gunnar Ottosson (Riksarkivet, Stockholm). In LEAF Newsletter Issue 1 (March 2002). The EAD (Encoded Archival Description) SGML/XML DTD "has elements for names of corporate bodies and persons with attributes allowing for links to authority files. There are also elements for the narrative administrative histories and biographies, as well as elements for controlled access in terms of functions and geographic names. However, EAD does not provide support for separate files of authority and context information. In response to this need, an international group of archivists and information scientists met in Toronto in March 2001 to lay down the principles for governing such an encoding standard. The group prepared for the meeting by drafting and reviewing a set of principles and criteria to direct its work, and agreed that the standard needs to address more than traditional authority control of headings and that accompanying documentation is needed for contextual information. The name of the format became the 'Encoded Archival Context', thereby stressing its wider scope: Archival context information consists of information describing the circumstances under which records (defined broadly here to include personal papers and records of organisations) have been created and used. This context includes the identification and characteristics of the persons, organisations, and families who have been the creators, users, or subjects of records, as well as the relationships amongst them. For the development of the DTD, a special working group was assigned consisting of Daniel Pitti (University of Virginia), Joanne Evens (University of Melbourne), Stephan Yearl (Yale University), and, from LEAF, Gunnar Karlsen (University of Bergen) and P-G Ottosson (National Archives of Sweden). During a meeting in Charlottesville in June, the group came up with a draft DTD, which was ready for circulation to the full group in the middle of July. The DTD has been successfully tested on LEAF data by Gunnar Karlsen. The EAC DTD is adopted to librarian standards for authority records, such as UNIMARC/Authorities. Especially when it came to the elements of the header and the entry elements it was regarded as crucial to keep a compatibility with MARC records. A special attribute (ea= encoding analog) documents the relation between an EAC element and the MARC field of the source. The Committee for Description Standards of the International Council of Archives is now reviewing the ISAAR(CPF): International Standard Archival Authority Record for Corporate Bodies, Persons and Families . Some of the members of the committee took part in the development of EAC, and it is proposed that the new version of ISAAR(CPF) shall accommodate the structure of EAC..." See: (1) "Encoded Archival Context Initiative (EAC)"; (2) "Linking and Exploring Authority Files (LEAF)"; (3) "Encoded Archival Description (EAD)"; general references in (4) "Markup Languages for Names and Addresses."

• [March 27, 2002] "XN3 - XML for N3." By Graham Moore (Vice President Research and Development, empolis GmbH). "This is a short paper that describes how the N3 notation can be represented using XML. We acknowledge that RDF exists and that the result of processing a N3 document can be equivalent to processing an XML RDF document. However there has been much comment in the RDF community about the verbosity and lack of clarity that exists in the XML serialisation of RDF. The community seems agreed on what the XML is expressing and this has been captured succinctly in N3. This paper shows how the ideas in N3 can be captured as an XML language. We have developed such a language and called it XN3 (XML N3). The aim of this language is to gain the useful property of parsability inherent in XML while being as simple, powerful and elegant as N3. We conclude this paper with some areas for improvement and make a general statement about XML development activities... The N3 notation and the associated primer are responsible for clearly communicating the elegance and simplicity that lies behind the RDF model. It achieves this through prose but also through a syntax, concise and precise syntax. The RDF XML serialisation does have these properties and is further confused by a 'concise' format. The RDF XML serialisation does have the benefit that it is XML. However the RDF model is not the XML model and any serialisation should enable easy, understandable interchange between the model and the syntax. What we attempt to do with XN3 (XML N3) is to maintain the power of XML as an easy to process markup language and keep the simplicity and elegance of N3... The following section describes how we have taken N3 and turned it into an XML language. It describes the different constructs from N3 and how they are represented in the XN3..."

• [March 27, 2002] "Specifying OLAP Cubes on XML Data." By Mikael Rune Jensen, Thomas H. Møller, and Torben Bach Pedersen (Database Systems Group, Institute for Electronic Systems, Department of Computer Science, Aalborg University, Denmark). In Journal of Intelligent Information Systems: Integrating Artificial Intelligence and Database Technologies Volume 17, Numbers 2/3 (December 2001), pages 255-280 (with 35 references). "On-Line Analytical Processing (OLAP) enables analysts to gain insight about data through fast and interactive access to a variety of possible views on information, organized in a dimensional model. The demand for data integration is rapidly becoming larger as more and more information sources appear in modern enterprises. In the data warehousing approach, selected information is extracted in advance and stored in a repository, yielding good query performance. However, in many situations a logical (rather than physical) integration of data is preferable. Previous web-based data integration efforts have focused almost exclusively on the logical level of data models, creating a need for techniques focused on the conceptual level. Also, previous integration techniques for web-based data have not addressed the special needs of OLAP tools such as handling dimensions with hierarchies. Extensible Markup Language (XML) is fast becoming the new standard for data representation and exchange on the World Wide Web. The rapid emergence of XML data on the web, e.g., business-to-business (B2B) e-commerce, is making it necessary for OLAP and other data analysis tools to handle XML data as well as traditional data formats. Based on a real-world case study, this paper presents an approach to specification of OLAP DBs based on web data. Unlike previous work, this approach takes special OLAP issues such as dimension hierarchies and correct aggregation of data into account. Also, the approach works on the conceptual level, using Unified Modeling Language (UML) as a basis for so-called UML snowflake diagrams that precisely capture the multidimensional structure of the data. An integration architecture that allows the logical integration of XML and relational data sources for use by OLAP tools is also presented... Motivated by the increasing use of OLAP tools for analyzing business data, and XML documents for exchanging information on the Web, this paper provides techniques that enable existing OLAP tools to exploit XML and relational data, without requiring physical integration of data. This paper proposed a multidimensional model, the UML snowflake diagram, enabling a precise specification of an OLAP DB based on multiple XML and/or relational data sources. The UML diagramming method was used for describing and visualizing the logical structure of XML documents, easing the design of the OLAP DB. The paper described how to handle the special considerations that need to be taken when designing an OLAP DB on top of XML data. Also, an architecture for integrating XML data at the conceptual level was presented. The architecture also supported relational data sources, making it well suited for building OLAP DBs which are based partly on in-house relational data and partly on XML data available on the web. We improve on previous work on integration of web-based data by focusing on data integration at the conceptual rather than the logical level. Also, the data integration approach takes special OLAP issues, such as handling dimensions with hierarchies and ensuring summarizability, into account. The implementation of a prototype using the approach described in this paper is currently in progress. A very important aspect of the implementation is to investigate efficient query processing techniques such as query translations and data caching. Storing higher-level summaries of the data can also speed up query processing considerably. Furthermore, if XML Schema advances to a W3C Recommendation it would be interesting to consider using this richer formalism for describing XML data sources instead of using DTDs. Other aspects of XML, such as whether preservation of document order is of relevance to OLAP analysis should also be investigated..." [abstract in part from the related Technical Report R-01-5003, Department of Computer Science, Aalborg University, June 13, 2001. For similar publications, see the bibliography page of Mikael R. Jensen.

• [March 27, 2002] "JavaOne: Sun Wades into Open-Source Waters with Java." By Ashlee Vance. In InfoWorld (March 27, 2002). "Sun Microsystems answered a long-standing call from open-source software developers Tuesday, saying Java fans will be able to submit some changes for the platform under open-source licenses and receive financial support from Sun for their projects. Sun's move toward a more open Java was announced by company Chairman and CEO Scott McNealy during a keynote address here at the JavaOne conference. Sun teamed with The Apache Software Foundation (ASF), maker of the popular Apache Server, to refine the procedures for open-source modifications of Java. The changes are designed to address issues that have dogged open-source companies looking to certify their products as Java compatible through the JCP (Java Community Process) that governs Java's maturation. Companies have been wary of submitting open changes for Java because of licensing issues, confidentiality concerns and the costs associated with running compatibility tests, said Jason Hunter, vice president of the ASF, joining McNealy on stage. As a response to some of these concerns, all Sun-led JSRs (Java Specification Requests) for standardizing a feature through the JCP can be submitted under an open-source license. In addition, test kits may also be submitted under the open licenses, Hunter said. Some existing JSRs will also be available for open-source implementations, he said. Sun has submitted more current JSRs than any other vendor... Sun did not say give the specifics of the open source license it will use for Java. Officials however indicated it would not use a license as broad as the GPL (General Public License) used in some open-source projects, which allows developers to freely modify and distribute code as long the changes are made public. Sun has long been under the watch of developers who were concerned about how much control the company exerts over a technology used by myriad companies. Sun, however, had voiced worries about the fragmentation of Java due to incompatible implementations of the technology from outside parties... With the move Tuesday, Sun may have assuaged some of the developers' fears and found a way to tap the talents of the Java community and open-source programmers as a whole. One company, however, remains unimpressed with Sun's new stance after fighting with the company in the past over open-source Java projects... Sun's close ties to the Apache Software Foundation on this project lend some credence to the company's intentions, as the ASF manages many of the open-source world's most successful projects. In a press conference after his speech, McNealy highlighted the importance of maintaining XML as a standard technology and of not allowing vendors to implement their own versions..." See "Java Community Processs Embraces Open Source."

• [March 27, 2002] "Microsoft Opens .Net Code to Academics." By George A. Chidi Jr. and Matt Berger. In InfoWorld (March 27, 2002). "Microsoft will allow academic researchers to view the nuts and bolts of some of the .Net source code the company will use in its wide-ranging initiative to supply applications and services over the Internet, Microsoft announced Wednesday. More than one million lines of source code for .Net will be made available under Microsoft's previously announced 'Shared Source' licensing program to academic researchers in university computer-science departments. Shared source is Microsoft's response to the open-source software movement and the growing popularity of the Linux operating system. Open-source software such as Linux typically is developed by programmers collaborating and freely sharing code updates. Under Microsoft's shared source license, developers have been able to view source code, but not modify it as they can with Linux. The shared-source implementation for .Net and Microsoft's Common Language Infrastructure for academics will run on the Windows XP operating system and the open-source FreeBSD derivative of the Unix operating system. Windows source code is also available to academics under shared source licensing, allowing noncommercial modification for academic and research purposes. Microsoft's source-code announcement Wednesday came as Sun Microsystems Inc. handed developers more pieces of its Java programming technology designed for building and deploying Web services, at the JavaOne Developer Conference in San Francisco. Sun Tuesday said developers will be able to submit some changes for Java under open-source licenses and receive financial support from the company for their projects. Microsoft, based in Redmond, Wash., has made a number of moves recently that have been seen as a reaction to both Sun's Java efforts and growing momentum for open-source projects. For example, Microsoft has submitted some of the underpinnings of its .Net initiative to a European standards body. Those technologies, which include the C# programming language and a component of its .Net Framework called CLI (Common Language Infrastructure), were approved as standards by the European Computer Manufacturers Association (ECMA) in December. Microsoft also funded an effort by software maker Corel to implement the ECMA standards and create the version of the .Net Framework for FreeBSD and testing. That implementation is what Microsoft will hand out under its latest academic deal... C#, a component-oriented programming language Microsoft developed, has been compared to Java in that, among other things, it is intended to allow developers to write code and reuse pieces of it when building various applications. CLI is the underlying technology for enabling developers to write .Net applications in more than 20 programming languages. Microsoft's implementation of those technologies is called the .Net Framework. The company intends to use .Net Framework as the common platform for Web services and software that link business processes together over the Internet with XML..." See "Microsoft Releases Shared Source CLI and C# Implementation Availability of Over 1 Million Lines of Source Code for FreeBSD and Windows Underscores Microsoft's Commitment to Open Standards, Academia and Developers."

• [March 26, 2002] "Exploring XML Encryption, Part 1. Demonstrating the Secure Exchange of Structured Data." By Bilal Siddiqui (CEO, WAP Monster). From IBM developerWorks, XML Zone. March 2002. ['XML Encryption provides end-to-end security for applications that require secure exchange of structured data. XML itself is the most popular technology for structuring data, and therefore XML-based encryption is the natural way to handle complex requirements for security in data interchange applications. Here in part 1 of this two-part series, Bilal explains how XML and security are proposed to be integrated into the W3C's Working Draft for XML Encryption.'] "Currently, Transport Layer Security (TLS) is the de facto standard for secure communication over the Internet. TLS is an end-to-end security protocol that follows the famous Secure Socket Layer (SSL). SSL was originally designed by Netscape, and its version 3.0 was later adapted by the Internet Engineering Task Force (IETF) while they were designing TLS. This is a very secure and reliable protocol that provides end-to-end security sessions between two parties. XML Encryption is not intended to replace or supersede SSL/TLS. Rather, it provides a mechanism for security requirements that are not covered by SSL. The following are a two important areas not addressed by SSL: (1) Encrypting part of the data being exchanged; (2) Secure sessions between more than two parties. With XML Encryption, each party can maintain secure or insecure states with any of the communicating parties. Both secure and non-secure data can be exchanged in the same document. For example, think of a secure chat application containing a number of chat rooms with several people in each room. XML-encrypted files can be exchanged between chatting partners so that data intended for one room will not be visible to other rooms. XML Encryption can handle both XML and non-XML (e.g., binary) data. We'll now demonstrate a simple exchange of data, making it secure through XML Encryption. We'll then slowly increase the complexity of the security requirements and explain the XML Encryption schema and the use of its different elements... In our next installment of this series of articles, we will discuss and implement the details of cryptography. We'll demonstrate the working of encryption and decryption classes and their interaction with parsing logic, and present applications of XML Encryption in Web services." See: "XML and Encryption."

• [March 27, 2002] "Donald Eastlake on XML Digital Signatures. An Interview With One of the Specification's Pioneers." By Larry Loeb [and Donald Eastlake]. From IBM developerWorks, XML Zone. March 2002. ['In this exclusive developerWorks interview, XML Digital Signatures pioneer Donald Eastlake responds to Larry Loeb's recent article on the topic by clarifying a number of issues about how this technology is used. Note from Larry Loeb: In a recent article on XML Digital Signatures, I questioned their utility and usefulness. Since the proposal has just been recommended for passage into general usage, I decided it was time to check back on the topic again. This time, I talked with Donald Eastlake, the editor of the XML Digital Signature (XMLDSIG) RFC, and someone who should know something about the subject, since he has been intimately involved with XML specifications since the effort began in the 1990s. He has also served on IETF efforts too numerous to list. His responses appear unedited, except for minor grammatical changes.'] Eastlake on real world use of XML digital signatures: "I believe there will be a full spectrum of usage but two areas of particular prominence seem likely: documents and messages. While these sometimes blend into each other, documents tend to be longer lived and the signatures on them tend to indicate human approval of all or part of the document, although they may also have time stamp signatures affixed automatically. Messages tend to be transient and would more commonly have authentication automatically affixed and removed. Of course, a message could include one or more documents, in the sense I'm using the word here, in its content... Documents are most likely to use public key techniques while messages, depending on the application, could use public key or symmetric secret key techniques. Documents are more likely to be something "important" like a mortgage or court filing. But if XML digital signatures are widely used for messages, messages could be several orders of magnitude more numerous." Article also in PDF format. See "XML Digital Signature (Signed XML - IETF/W3C)."

• [March 26, 2002] "Streaming API for XML (StAX)." Java Specification Request #173. Specification Lead: Christopher Fry (BEA Systems). ['The Streaming API for XML (StAX) is a Java based API for pull-parsing XML.'] Initial Expert Group Membership: BEA Systems; James Clark, Thai Open Source Software Center; K Karun, Oracle Corporation; Gregory Messner, The Breeze Factor; Aleksander Slominski, Indiana University; James Strachan, dom4j; Anil Vijendran, Sun Microsystems. "The Streaming API for XML (StAX) parsing will specify a Java-based, pull-parsing API for XML. The streaming API gives parsing control to the programmer by exposing a simple iterator based API. This allows the programmer to ask for the next event (pull the event) and allows state to be stored in a procedural fashion. Two recently proposed JSRs, JAXB and JAX-RPC, highlight the need for an XML Streaming API. Both data binding and remote procedure calling (RPC) require processing of XML as a stream of events, where the current context of the XML defines subsequent processing of the XML. A streaming API makes this type of code much more natural to write than SAX, and much more efficient than DOM. The goal of this API is to develop APIs and conventions that support processing XML as a stream. The specification will address three main areas: (1) Develop APIs and conventions that allow a user to programmatically pull parse events from an XML input stream. (2) Develop APIs that allow a user to write events to an XML output stream. (3) Develop a set of objects and interfaces that encapsulate the information contained in an XML stream. The specification should be easy to use, efficient, and not require a grammar. It should include support for namespaces, and associated XML constructs. The specification will make reasonable efforts to define APIs that are 'pluggable'... Two standard main approaches for processing XML exist: (1) the Simple API for XML processing [SAX] and (2) DOM [Document Object Model]... To use SAX one writes handlers (objects that implement the various SAX handler APIs) that receive callbacks during the processing of an XML document. The main benefits of this style of XML document processing are that it is efficient, flexible, and relatively low level. It is also possible to change handlers during the processing of an XML document allowing one to use different handlers for different sections of the document. One drawback to the SAX API is that the programmer must keep track of the current state of the document in the code each time one processes an XML document. This creates overhead for XML processing and may lead to convoluted document processing code... DOM provides APIs to the programmer to manipulate the XML as a tree. At first glance this seems like a win for the application developer because it does not require writing specific parsing code. However this perceived simplicity comes at a very high cost: performance. Some implementations require the entire document to be read into memory, so for very large documents one must read the entire document into memory before taking appropriate actions based on the data. Another drawback is the programmer must use the DOM tree as the base for handling XML in the document. For many applications the tree model may not be the most natural representation for the data..." See the full list of JSRs.

• [March 26, 2002] "The Java XML Pack, Spring 02 Release." "The Spring 02 Release includes the following: (1) Java API for XML Messaging (JAXM) v1.0.1 EA2; (2) Java API for XML Processing (JAXP) v1.2 EA2; (3) Java API for XML Registries (JAXR) v1.0 EA2; (4) Java API for XML-based RPC (JAX-RPC) v1.0 EA2. This release of the Java XML Pack has been tested with various configurations, using Tomcat 4.0.1 and J2EETM 1.3_01 and 1.3.1 with Java 2 SDK, Standard Edition (J2SETM) versions 1.3.1_02 and 1.4 on the following platforms: Solaris 2.8, Windows 2000, Professional Edition, Windows XP, Professional Edition, RedHat Linux 7.2... The Java XML Pack is an all-in-one download of Java technologies for XML. Java XML Pack brings together several of the key industry standards for XML -- such as SAX, DOM, XSLT, SOAP, UDDI, ebXML, and WSDL -- into one convenient download, thereby giving developers the technologies needed to get started with web applications and services. Bundling the Java XML technologies together into a Java XML Pack ensures Java developers of a quick and easy development cycle for integration of XML functionality and standards support into their applications. Through support of these technologies in conjunction with the Java Platform, Java XML Pack technology enables interoperability between applications, services, and trading partners through a vendor-neutral platform that allows for sharing of custom industry standard data formats. The Java XML Pack includes current publicly-available releases of Java APIs and Architectures for XML, both production and early access (EA) versions. The Java XML Pack will have frequent quarterly refreshes to ensure the underlying Java XML technology is the latest available..." See also: "Java Technology and XML: Frequently Asked Questions."

• [March 26, 2002] "System Integrated Automaton Parser for XML (SIA Parser)." Communiqué 2002-03-26 from Robert Berlinski. Version: March, 2002. "Available for free... "...a new implementation of the parser. The most important is a new automaton engine that improves efficiency by 14% to 22%. Besides that classes have new interface and are not compatible with the previous versions. Please expect a few minor improvements in the near future... The SIA Parser improves SAX by integrating an automaton within it. Generally speaking the SIA Parser retains all SAX's functionality and additionally makes very simple to: (1) Uniquely identify XML nodes by state numbers. In other words a reference to a particular node can be made by a unique state ID. And the process of matching nodes with state numbers is very simple. (2) Automatically generate a source code to parse a particular XML. Just run the generator against your XML data file, save the source code, fill in business logic, generate code and your application is done. (3) Parse altering XML that might include nested XML and process the nested XML. (4) Work in self-learning mode to accept any XML and perform general tasks. (5) Provide statistical and structural information about an XML... The SAX parser offers a great efficiency and is faster than DOM parser. On the other hand the DOM parser provides structure information regarding parsed XML. It is very important since, an XML might have might have different nodes in different positions but with the same names. The SAX parser provides only local information about the structure (events: startDocument, endDocument, startElement, endElement). Then it is up to the application to keep track of the information to build the global state. The SIA Parser was introduces to fill up the gap. It is possible by integrating an automaton with the SAX parser. An universal automatic mechanism builds a new interface for application. The interface provides information about global state plus all the information available from SAX parser. Additionally it is possible to build universal tools based on the SIA parser to solve common issues like: Formatting an XML to a readable form Providing statistics about an XML Automatically generating dedicated parsers for an XML The SAX roots guarantees high performance while the integrated SIA automaton helps with Rapid Application Development and reduce code maintains costs..."

• [March 26, 2002] "Using Object-Oriented Attribute Grammars as ODB System Generator." By Takashi Imaizumi, Takeshi Hagiwara, Katsuhiko Gondow, and Takuya Katayama. Department of Information Engineering, Faculty of Engineering, Niigata University, Niigata 950-2181, Japan. Presented at the Third Workshop on Attribute Grammars and their Applications (WAGA'00), Ponte de Lima, Portugal. July 7, 2000. 20 pages. "This paper presents MAGE2 system. It implements a computational model OOAG (Object-Oriented Attribute Grammars) and creates its attributed object trees in object-oriented database (ODB) using persistent object allocation mechanism of object-oriented database management systems (ODBMS). The MAGE2 is a programming support and execution environment for OOAG. The focus of this paper is on an execution system. We indicate core techniques to implement MAGE2, that is, how to execute specifications of OOAG and how to generate an ODB system. We are planning to use MAGE2 to design databases for storing data that have logical structures such as program source files, XML documents and so on... OOAG has been derived from attribute grammars. Declarative structures, separation of semantics and syntax definition, and local description resulting in high readability and high maintainability, and clear description due to functional computation of attributes are all desirable characteristics of AGs. We summarize the OOAG features as a generator of database systems as follows: (1) OOAG has been derived from attribute grammars; (2) We can program how to manipulate software objects by message passing; (3) We can describe data structure and manipulation method of software objects at the same place; (4) We can generate software repository system automatically from formal repository specification written in OSL language. An OOAG description is separated into two parts: one is a static specification and the other is a dynamic specification. They are described in a specification language OSL 'Object Specification Language'. We describe briefly each part and then give the correspondence of OSL language constructs to conventional attribute grammars constructs... A tool constructed by the MAGE system creates attributed object trees in an ODB persistently. Operations to persistent object trees can be described in OSL specifications by the message passing mechanism of OOAG model. Programmers who use MAGE will only write interface codes between generated tool. Created ODBs will be maintained by the OOAG evaluator. This includes updating, adding, or deleting objects. They will be described in dynamic subtrees operation by message passing. If the state of object trees in the database will be inconsistent, OOAG evaluation loop will keep them consistent. From above features of the MAGE system, we can develop complicated object-oriented database systems which manage structured data effciently..." See also "XML and Attribute Grammars." [source, Postscript]

• [March 26, 2002] "SmartTools: A Development Environment Generator Based on XML Technologies." By Isabelle Attali, Carine Courbis, Pascal Degenne, Alexandre Fau, Joël Fillon, Didier Parigot, Claude Pasquier, and Claudio Sacerdoti Coen. In XML Technologies and Software Engineering, Toronto, Canada. ICSE'2001, ICSE Workshop Proceedings. "SmartTools is a development environment generator that provides a structure editor and semantic tools as main features. SmartTools is easy to use, thanks to its graphical user interface. Being based on Java and XML technologies offers all the features of SmartTools to any defined language. The main goal of this tool is to provide help and support for designing software development environments for programming languages as well as domain-specific languages defined with XML technologies... From the abstract syntax definition of programming (e.g., Java) or domain-specific languages, it is possible to easily generate an interactive environment with SmartTools. This latter automatically offers a well-known visitor pattern technique to specify semantic analysis on DOM tree structures. Its graphical part is mainly based on free existing implementations of standards (XSLT, BML). We have chosen to use non-proprietary APIs in the concern to be open and take advantage of future or external developments. Thus, we can focus on semantics tools (visitor technics, aspect-oriented programming). There are already some examples of easy and successful integration of research tools, and technology transfer in industrial environment. Additionally, we hope to benefit from the large fields of applications that appear through XML technologies. Also in Postscript format. See similarly "SmartTools: A Generator of Interactive Environments Tools," in ETAPS'2001: Electronic Notes in Theoretical Computer Science (ENTCS). Tools Demonstrations at CC'01, edited by Reinhard Wilhelm. Project URL: see "SmartTools System: Aspect and XML-oriented Semantic Framework Generator." From the section 'Using XML technologies': "As XML will be more and more used as a communication protocol between applications, we wanted to be able to handle any XML document in SmartTools. Any XML document importing a DTD (Document Type Definition) has a typed structure. That DTD describes the nodes and their types, that is very similar to our AST formalism. In order to obtain this result, we have specified and implemented a tool which converts a DTD formalism into an AST equivalent formalism. With this conversion, we automatically offer a structure editing environment for all languages defined with XML in the SmartTools framework. It is important to note that XML documents produced by SmartTools are well-formed... We are also studying XML schemas and RDF (Resource Description Framework) schemas, the successors of DTD. Thus any application that respects the implementation of the APIs, can be XML-compliant. All the manipulated trees in SmartTools are Java DOM Trees to ease the integration with other tools and to have a very open data structure. We offer a tool to automatically generate parsers. This tool can be useful for a designer to define a user-friendly concrete syntax for his language. But, extra data are required in the definition of the language. We have also integrated the XSL (XML Style-sheet Language) specifications that describe the layout of a document as well as the XSLT (XSL Transformation).

• [March 26, 2002] "Standardizing XML Rules: Rules for E-Business on the Semantic Web." Invited Presentation (45-minutes, presentation, with slides in PDF format). By Benjamin N. Grosof (MIT Sloan Professor in E-Commerce Information Technology). August 5, 2001. Presented at the Workshop on E-business and the Intelligent Web at the International Joint Conference on Artificial Intelligence (IJCAI-01). See also the short paper; preliminary prose outline of the talk, and appears in the Workshop Proceedings. The principal topic of discussion is the Rule Markup Language (RuleML). See: "Rule Markup Language (RuleML)." [alt URL for paper; cache]

• [March 26, 2002] "Facilitating Semantic Web Search with Embedded Grammar Tags." By Gautham K. Dorai and Yaser Yacoob (Department of Computer Science, University of Maryland, College Park, MD, USA 20742). August 5, 2001. Presented at the Workshop on E-business and the Intelligent Web at the International Joint Conference on Artificial Intelligence (IJCAI-01). 6 pages. "We propose a new framework for intelligent information access. The backbone of this framework consists of embedded grammar tags (EGT's) that capture natural language queries. These embedded grammar tags reflect information content in web pages by anticipating the queries that may be launched by users to retrieve a particular content. These grammars provide a unifying component for speech recognition engines, semantic web page representation and speech output generation. We demonstrate the new EGT representation to enable a software agent to respond to natural speech input from users in narrow domains such as weather, stock market and news queries. [...] In this paper a new semantic tagging representation (i.e., EGT) was proposed and developed. The tagging approach is a departure from existing definition and use of tags in XML, RDF and DAML. Employing BNF grammar to represent the queries which users may employ to recover information changes the current view of semantic content of web pages since we reach beyond meaning into anticipation of query syntax and semantics. There are far reaching impacts to this proposal. First, the designer of the web is given the role of anticipating the queries that are matched to particular content items. Second, the web-search engine is relieved from the load of performing NLP since the mapping between queries and content has been already programmed into the page. Third, users can creatively expand the semantic reach of the content of web-pages by simply creating new EGTs that reflect potential queries." [cache]

• [March 26, 2002] "An Expressive Constraint Language for Semantic Web Applications." By Peter Gray, Kit Hui, and Alun Preece (University of Aberdeen, Computing Science Department, Aberdeen AB24 3UE, Scotland). Presented at the Workshop on E-business and the Intelligent Web at the International Joint Conference on Artificial Intelligence (IJCAI-01). 8 pages. "We present a framework for semantic web applications based on constraint interchange and processing. At the core of the framework is a well-established semantic data model (P/FDM) with an associated expressive constraint language (Colan). To allow data instances to be transported across a network, we map our data model to the RDF Schema speci- fication. To allow constraints to be transported, we define a Constraint Interchange Format (CIF) in the form of an RDF Schema for Colan, allowing each constraint to be defined as a resource in its own right. We show that, because Colan is essentially a syntactically-sugared form of first-order logic, and P/FDM is based on the widely-used extended ER model, our CIF is actually very widely applicable and reusable. Finally, we outline a set of services for constraint fusion and solving, which are particularly applicable to business-tobusiness e-commerce applications. All of these services can be accessed using the CIF... XML Constraint Interchange Format: "In defining our Constraint Interchange Format, we were guided by the following design principles: (1) the CIF would need to be serialisable into XML, to make it maximally portable and open; (2) constraints should be represented as resources in RDF, so that RDF statements can be made about the constraints themselves; (3) there must be no modification to the existing RDF and RDF Schema specifications, so that the CIF would be layered cleanly on top of RDF; (4) it must be possible for constraints to refer to terms de- fined in any RDF Schema, with such references made explicit. As we showed in the previous section, the entity-relational basis of both our P/FDM data model and RDF made it relatively straightforward to map from the former to the latter. In building the RDF Schema for our CIF we were guided by the existing grammar for Colan which relates constraints to entities, attributes and relationships present in the ER model. This grammar serves as a metaschema for the Colan constraints (such metaschemas are very common in relational and object database systems). A number of issues arose in developing the RDF Schema for CIF, discussed in the following subsections... At the core of the framework is a well-established semantic data model (P/FDM) with an associated expressive constraint language (Colan). To allow data instances to be transported across a network, we have mapped our data model to the less expressive (but adequate) RDF Schema. To allow constraints to be transported, we have provided a Constraint Interchange Format (CIF) in the form of an RDF Schema for Colan, allowing each constraint to be defined as a resource in its own right. Because Colan is essentially a syntactically-sugared form of first-order logic, and P/FDM is based on the widely-used extended ER model, our CIF is actually very widely applicable and reusable... In linking Colan to RDF Schema, we also allow its usage with more expressive data modelling languages built on top of RDF Schema, including DAML-ONT and OIL. However, a basic requirement of our approach in defining the RDF Schema for Colan expressionswas that it should in no way require modification to the underlying RDF definitions (this is in contrast to the OIL approach, which requires modification at the RDF layer in order to capture certain kinds of expression. Our constraint interchange and solving services are being incorporated into the AKT infrastructure, as one of the basic knowledge reuse mechanisms in the AKT service layer. Further information on this work can be found at www.aktors.org..." [cache]

• [March 26, 2002] "Generating Web Content with Cocoon. [Exploring XML.]" By Michael Classen. From WebReference.com. March 18, 2002. ['Cocoon provides for developers a way to generate content dynamically using XML data. XML expert Michael Classen takes a look at the version 2 release, which, among other things, improves scalability by using SAX instead of the DOM.'] "The Apache project is well-known for the Web server software it produces that is carrying its name. In the past, many other interesting software projects were also started there, mainly in the Java and XML space. Cocoon is one of them. Cocoon is a Java Web-application for generating dynamic content using XML. It can be installed on any Java Servlet Engine and comes with a wide variety of components for generating, transforming and outputting data with XML. Cocoon 2 was recently released as a complete rewrite of its predecessor, with improved flexibility and scalability. The central concept in Cocoon is the pipeline, a number of components plugged together in a serial configuration to process incoming data that will be passed along... The Cocoon developers set out to create a similar system for generating content on the Web by piping XML through a configurable set of tools. The first version of the software was passing around full DOM documents, limiting scalability with regard to the size of documents that could be processed, and the amount of parallelism in the pipeline. Furthermore, the pipeline was defined through processing instructions within the documents, making reuse in different contexts difficult. Version 2 eliminates these problems by using SAX instead of DOM, and connecting the processing components through SAX events. This way XML documents of arbitrary size can be processed, and the components can work in parallel on the same document. The configuration of the pipeline is now moved out of the data documents and into a separate sitemap file... out of which components can a pipeline be built? Cocoon comes with many configurable components for generating, transforming and serializing data with XML... The Cocoon framework is a powerful software application for dynamically generating Web content without needing to know a programming language. Although it is written in Java, by no means do you have to use or know Java, short of configuring a Web application for a servlet engine such as Tomcat. Cocoon 2 eliminates the shortcomings of Version 1 and provides an interesting alternative to your favorite scripting language..."

• [March 26, 2002] "HP Adds Transaction Support To Web Services: Java One." By Richard Karpinski. In InternetWeek (March 25, 2002). "Hewlett-Packard this week will release what it claims is the first implementation of an emerging XML protocol that will let emerging Web services infrastructures better handle business transactions. HP's new Web Services Transaction Server 1.0 is based on the OASIS Group's Business Transaction Protocol (BTP) specification. While Web services offer great flexibility with their loosely coupled architecture, that doesn't translate well into a more transaction-oriented environment where messages must be passed in a timely and reliable manner. Traditionally, systems such as transaction-processing monitors have emerged to enable such highly reliable software environments. The BTP specification aims to bring the same reliability to the world of XML and Web services, said Joe McGonnell, HP's product manager for Web services. The HP transaction server features an implementation of JTS, or Java Transaction Service, underneath the covers, working at an API level, said McGonnell. Meanwhile the new BTP implementation works at a higher level, coordinating how SOAP messages are sent back and forth by a Web service... In other news from Java One, HP is releasing its Web Services Platform version 2.0, a developer environment for creating, deploying, and registering Web services. The tool integrates with the HP Application Server, as well as app servers from other vendors. The HP platform also places a major emphasis on bridging the gap between Java- and .Net-based Web services. HP -- which runs a public UDDI node -- is also releasing a new version of its Web Services Registry 2.0, to help users build private UDDI registries..."

• [March 25, 2002] "A URN Namespace for the Web3D Consortium (Web3D)." By Aaron E. Walsh (Mantis Development Corp.; WWW). IETF Network Working Group, Internet-Draft. Reference: 'draft-walsh-urn-web3d-00.txt'. March 25, 2002, expires: September, 25 2002. "This document describes a Uniform Resource Name (URN) namespace for the Web3D Consortium (Web3D) for naming persistent resources such as technical documents and specifications, Virtual Reality Modeling Language (VRML) and Extensible 3D (X3D) files and resources, Extensible Markup Language (XML) Document Type Definitions (DTDs), XML Schemas, namespaces, style sheets, media assets, and other resources produced or managed by Web3D. Web3D is the only non-profit organization with a mandate to develop and promote open standards to enable 3D for the Internet, Web and broadcast applications. Web3D is responsible for developing, advancing, and maintaining the VRML97 ISO/IEC International Standard (ISO/IEC 14772-1:1997), X3D (the forthcoming official successor to VRML) and related technologies..." See: "VRML (Virtual Reality Modeling Language) and X3D." [cache]

• [March 25, 2002] "Java, XML, and Web Services." By Jon Udell. In InfoWorld (March 22, 2002). "Simple text messages, readable and writable by people and computers, live at the core of every successful Internet application. XML seeks to grow the expressive power of these texts while preserving their accessibility. Java, although born to the Internet, has been oddly slow to embrace these paradigms. For example, regular expressions are the most basic tool for working with patterned text. Yet only now, in the JDK (Java Development Kit) 1.4 release, do regular expressions become a standard feature of the Java platform. Likewise, basic XML facilities such as parsing with SAX (Simple API for XML) and DOM (Document Object Model) interfaces, and transformation with XSLT (Extensible Stylesheet Transformation) -- although long available from other sources -- make their first official debut in J2SE (Java 2 Standard Edition) 1.4. Although Sun's Java/XML engine may have started slowly, it's really cranking now. A set of unbundled XML and Web-services APIs, in various stages of development, seeks to complement the XML core that's built into the platform. These "JAX Pack" APIs define a Java framework within which developers can perform several tasks... So what exactly are the features of Sun's emerging Web services model? For Hal Stern, CTO of iPlanet's software division, there are three core activities: creating service endpoints, assembling services into business processes, and deploying these in ways that administrators can control and users can comprehend... Creating context for Web services is the charter of ebXML, one of the messaging profiles supported by JAXM (Java API for XML Messaging); another JAXM profile is WS-Routing, formerly SOAP-RP. But business-collaboration protocols such as ebXML will not soon, and may never, solve the kinds of semantic problems that plague systems integrators who regularly struggle with the need to match one company's definition of supplier, customer, or purchase order to another's... Clearly there will be lots of ways to produce and consume SOAP services in Java. Too many, perhaps, but when you're bootstrapping it's wise to accommodate a broad range of legacy systems and attitudes. The real question for Java developers, and indeed for all developers, is how to contextualize the use of those services. To that end, iPlanet's Stern argues for "a thin waistline of core standards" -- just SOAP and WSDL and UDDI. "Then let's innovate on top of these to solve the assembly problem," he says. At this level, conventional programming languages fade into the woodwork. The focus shifts to languages that are today spoken, and protocols that are today enacted, by people. When a company signs a new supplier, Stern points out, lawyers gather in a room to negotiate terms and conditions, and all documents subsequently exchanged fall within the scope of that agreement. ebXML addresses this realm. So does IBM's WSFL (Web Services Flow Language), and Microsoft's XLANG, the orchestration dialect of BizTalk Server. Until basic Web services find their way into routine use, we won't be able to fully evaluate these approaches to composing systems based on them..."

• [March 25, 2002] "Iona Advances Web Services Platform, Adds Security: JavaOne." By Richard Karpinski. In InternetWeek (March 25, 2002). "Vendor Iona Inc. is adding new capabilities to its Web services tools, including support for the latest Java standards and a new security framework that addresses a key missing piece of the Web services puzzle. Iona this week is rolling out a new version of its core developer platform. Iona XMLBus Edition 5.1 includes new security tools, improved developer features, and the promise of a new UDDI server to be added shortly. The big addition is the security framework, the Iona Security Service, which lets developers use existing security databases -- initially LDAP but later Active Directory and other platforms -- to implement a password-protection scheme for their Web services. The service is based on SAML, or Security Assurance Markup Language, which provides standards for distributing authentication, such as in a Web services architecture. In later releases, IONA will add single sign-on and other security features to the product, including integration with PKI products from VeriSign and others... In addition to the new security framework, Iona is also adding new intelligent interface mapping tools to XMLBus that will let developers build WSDL -- or Web Services Description Language -- descriptions of Web services without a lot of hand-coding, Rymer said. In addition, the vendor plans to add a private UDDI repository to the tool within the next 30 days..." See the announcement: Iona Announces Web Services Security Framework. IONA Security Services Deliver Open and Comprehensive Solution for End 2 Anywhere Integration of Enterprise Applications Across the Internet."

• [March 25, 2002] "OASIS Hones Web Services Standards." By Tom Sullivan and Ed Scannell. In InfoWorld (March 22, 2002). "Looking to take Web services protocols higher up the interoperability stack, two groups within the Organization for the Advancement of Structured Information Standards (OASIS) are developing specifications for content delivery and end-user interfaces. Known as Web Services for Interactive Applications (WSIA) and Web Services for Remote Portals (WSRP), which met this week, the groups were created to advance user-facing Web services and enable Web services and other applications to plug and play with portals and portlets. Building on this momentum, Sun Microsystems and IBM plan to announce on Monday at JavaOne a portlet specification submitted to the Java Community Process (JCP) that complements Billerica, Mass.-based OASIS' WSRP group. Thus far, the core Web services standards -- SOAP (Simple Object Access Protocol), XML, UDDI (Universal Description, Discovery, and Integration), and WSDL (Web Services Description Language) -- have focused on system-to-system interoperability. The standard expected to emerge from the WSIA, however, would improve any service that requires users to fill out online forms, for example, said Dwight Davis, an analyst at Summit Strategies in Kirkland, Wash... recognizing this need, a host of companies have backed the WSIA initiative, including IBM, BEA Systems, Bowstreet, divine, Documentum, Epicentric, and Plumtree. And the lineup of WSRP supporters looks similar, with Documentum, Epicentric, divine, IBM, Sun, Hewlett-Packard, Iona, and Oracle all on board. 'There is a certain set of base functions that we are trying to do jointly between the two committees, and then WSIA will try to go beyond that and do some things that are not required for portals,' explained Charles Wiecha, manager of the next-generation user experience frameworks department at Yorktown Heights, N.Y.-based IBM Research and chair of the WSIA committee. The technologies expected to drive the WSIA standard include IBM Research's WSXL (Web Services Experience Language) and the combined work on Web services graphical interfaces done by Epicentric and divine. IBM has also included in its WSXL proposal plans for XLink (XML Linking Language) to be used to hook together a patchwork of Web services to make them appear as a single application..." See (1) "Web Services for Remote Portals (WSRP)"; (2) "Web Services for Interactive Applications (WSIA)."

• [March 25, 2002] "Extensible Rights Markup Language (XrML) Interoperability with Digital Transmission Content Protection (DTCP)." By ContentGuard, Inc., with contributions from Intel Corporation and Microsoft Corporation. 2002. ['This paper addresses interoperability across the digital content industry with its multiple devices and a myriad of different business models. This interoperability is based on open widely accepted standards within the industry and will allow for maximum flexibility for content owners, device manufacturers and consumers.'] "As a proof of concept, the following technical discussion will address the manner in which leading industry standards, XrML and the rights expression function within DTCP, are capable of interoperability. XrML is a semantically precise language for expressing rights and business rules related to the use, duplication and distribution of content. DTCP, also sometimes referred to as '5C, is a specification that enables secure distribution of digital content between devices across IEEE 1394 and other home network interconnects. We will discuss the benefits of using XrML in combination with DTCP to expand the range of application of both technologies, and to explore ways for rights management systems using XrML to interoperate with devices that support DTCP. A guiding principle in the technical approach is to ensure systems using either or both technologies can relate to each other in a way that content can efficiently flow between them while retaining the content owner's expressed rights, rules and restrictions... Devices that are built today based on the DTCP specification have been granted certain usage rights for the DTCP protected content that they receive. These rights are bound to the content itself via the CCI bits. XrML has the ability to specify the use of DTCP when permitting the export of content to devices. By enabling interoperability between these technologies, industry and consumers can take part in a broader set of business models and can maximize opportunities throughout the content value chain. As a business case example, Microsoft's DRM technology, incorporating XrML, will be capable of enabling interoperability with DTCP. This approach will bring together the benefits of a robust digital rights language and a high degree of protection for entertainment content distribution to the consumer. This in turn will help to demonstrate the foundation of technology and standards needed to enable a more rapid transition to the digital economy..." See "Extensible Rights Markup Language (XrML)" and the recent TC proposal, "OASIS Members Propose a Rights Language Technical Committee."

• [March 22, 2002] "RELAX NG Schemas for TEI P4." Prepared by Sebastian Rahtz (OUCS Information Manager). See also the ZIP package. Sebastian has prepared RELAX NG schemas for the TEI "which are up to date with the latest version of P4 (now effectively frozen), and are derived automatically from the [ODD] source of TEI P4. I have been working on this for some time, but please regard it as a personal project for now, and not a product of the TEI. It is not intended to be used in production... There is no documentation yet, and only one example. You can validate test0.xml against test0.rng. test0.rng is the base example showing how to construct an instance schema. I will be added more complex test cases in due course... I have tested this with James Clark's "jing", and Sun's "MSV" tool. Sun's "relmes" tool, which allows Schematron assertions to be added, also works, but not the public release. The author is hoping to get a new release out soon. Anyone attending XML Europe 2002 in May may like to come and hear me give a talk about this work. Or of course I am happy to discuss it in public or private..." [XML Europe 2002, Wednesday, 22-May-2002: "TEI and RELAX NG." Presented by: Sebastian Rahtz, Information Manager, Oxford University Computing Services, United Kingdom. This presentation describes work undertaken to show how the Guidelines can use fragments of the Relax NG schema language internally, and generate either full schemata or DTDs on demand. It will also show how it can evolve to keep up with modern standards."] References: "Text Encoding Initiative (TEI) - XML for TEI Lite."

• [March 22, 2002] "What is XSL-FO?" By G. Ken Holman. From XML.com. March 20, 2002. ['In an extended excerpt from his renowned training materials, Ken Holman explains the W3C's XSL Formatting Objects technology, XSL-FO, intended to facilitate page-based formatting of XML documents. Ken introduces XSL-FO's basic concepts and processing model, and places it in the context of XML and XSLT. Including plenty of examples and diagrams, "What is XSL-FO?" should give you a good grounding and leave you ready to start experimenting with this exciting technology.'] "Crane Softwrights Ltd. has published Practical Formatting Using XSLFO covering every formatting object of XSLFO and their properties, according to the final XSL 1.0 Recommendation of October 15, 2001. The first two chapters of this book have been rewritten in prose and are made available here as an introduction to the technology and its use. This material assumes no prior knowledge of XSLFO and guides the reader through background, context, structure, concepts, introductory terminology, and a short introduction of each of the formatting objects. Note that neither the Recommendation itself, nor Crane's training material, attempt to teach facets of typography and attractive or appropriate layout style, only the semantics of formatting, the implementation of those semantics, and the nuances of control available to the stylesheet writer and implemented by the stylesheet formatting tool. XSLFO is a very powerful language with which we can possibly create very ugly or very beautiful pages from our XML-based information... Two vocabularies specified in separate W3C Recommendations provide for the two distinct styling processes of transforming and rendering XML instances. The Extensible Stylesheet Language Transformations (XSLT) is a templating markup language used to express how a processor creates a transformed result from an instance of XML information. The Extensible Stylesheet Language Formatting Objects (XSLFO) is a pagination markup language describing a rendering vocabulary capturing the semantics of formatting information for paginated presentation. Formally named Extensible Stylesheet Language (XSL), this Recommendation normatively incorporates the entire XSLT Recommendation by reference and, historically, used to be defined together in a single W3C draft Recommendation..." See also the two "how-to" articles of J. David Eisenberg on XSL-FO, published last year: [1], [2]. For related resources, see "Extensible Stylesheet Language (XSL/XSLT)."

• [March 22, 2002] "What's New in XPath 2.0." By Evan Lenz. From XML.com. March 20, 2002. ['Evan Lenz presents the first part of a two-part series on the next generation of XSLT and XPath. In "What's New in XPath 2.0" Evan explains the new features available in XPath, and its relationship to the W3C XML Query language.'] "This article provides a brief tour through some of the new features in XPath 2.0. It assumes that you already have a basic understanding of XPath 1.0, and that you've most likely used it in the context of XSLT. It is by no means an exhaustive overview but merely points out some of the most noteworthy features. Relationship between XPath 1.0 and XPath 2.0: Both the XPath 1.0 recommendation and the latest XPath 2.0 working draft say that "XPath is a language for addressing parts of an XML document". This was a fairly appropriate characterization of XPath 1.0. (Of course, it doesn't mention that you can have arithmetic expressions and string, number, and boolean expressions, but those features were kept to a minimum.) On the other hand, as a characterization of XPath 2.0, it leaves a lot to be desired. XPath 2.0 is a much more powerful language that operates on a much larger domain of data types. A better way of describing XPath 2.0 is as an expression language for processing sequences, with built-in support for querying XML documents. Querying? Isn't that XQuery's job? Relationship between XPath 2.0 and XQuery 1.0: For over a year now, the W3C XSL and XML Query Working Groups have been working closely together. The goal has been to share as much between XSLT 2.0 and XQuery 1.0 as is technically and politically feasible and to give that common subset the name "XPath 2.0". This effectively means that the driving forces behind XPath 2.0 include not only the XPath 2.0 Requirements document but also many of the XML Query language requirements... XPath 2.0 is a strict syntactic subset of XQuery 1.0. In fact, both working drafts and language grammars were automatically generated from a common source..."

• [March 22, 2002] "Introducing XML::SAX::Machines, Part Two." By Kip Hampton. From XML.com. March 20, 2002. ['Kip Hampton returns with the second installment of his introduction to the XML::SAX::Machines Perl module.'] "In last month's column we began our introduction to XML::SAX::Machines, a group of modules which greatly simplifies the creation of complex SAX application with multiple filters. This month we pick up where we left off by further illustrating how XML::SAX::Machines can be used to remove most of the drudgery of building SAX-based XML processing applications..."

• [March 22, 2002] "Web Service Sublimation." By Martin Gudgin and Timothy Ewald. From XML.com. March 20, 2002. [Tim Ewald and Martin Gudgin plunge naked into the slimy pool of debate and attempt to catch the slippery fish that is the real definition of a "web service."] "In the broadest possible sense, Web Services are an attempt to use XML to build distributed information processing systems that work across the Internet without necessarily requiring a browser as the client. Many present Web Services as a silver bullet that makes building this sort of system easy, but this view is naive. Serialized XML messages are easy to parse because the syntactical rules of XML 1.0 + Namespaces are well understood. Once parsed, XML messages are easy to manipulate using a range of technologies. However, while the ability to parse and interpret messages is necessary, it is not sufficient to build a distributed system. There are a lot of other issues that must be resolved. How should messages flow between different parts of the system? Should the messages by typed or untyped? If they are typed, what type system should be used? And should parts of the system be strongly or loosely coupled? Answering these questions is key to deciding what Web Services really are. But deciding on answers is extremely difficult, as recent debates in the XML world have shown ... Collectively, while people envision Internet-based distributed information processing applications sending messages based on a wide array of patterns, including but not limited to request-response, it isn't clear how that will be done relative to HTTP as it is defined today. Independent of message flows, people have not yet agreed on whether messages should be typed, which type system to use, and what degree of coupling is acceptable. (For the record, messages should be typed, described in XSD, and as loosely coupled as possible -- as specified in their XSD definitions.) So what is a Web Service? It is an Internet-friendly distributed application that uses XML. That's about all anyone can say for now."

• [March 22, 2002] "SAML Advances Single Sign-On Prospects." By Andy Patrizio. In XML Magzine Volume 3, Number 2 (March 2002), pages 10-11. ['Promising a standard means of authentication and authorization, SAML passes an important OASIS milestone.'] "The Organization for the Advancement of Structured Information Standards (OASIS) has completed the heavy lifting on its latest XML standard, the Security Assertion Markup Language (SAML), a standard for exchanging authentication and authorization information between domains. SAML (pronounced 'sam-el') is designed to offer single sign-on for both automatic and manual interactions between systems. It will let users log into another domain and define all of their permissions, or it will manage automated B2B exchanges between two parties. SAML addressed the need to have an industry standard way of representing assertions of authentication and authorization for users and interactions, according to Jeff Hodges, co-chair of the Security Services Technical Committee (SSTC) at OASIS that developed the spec and principal engineer at Oblix... SAML replaces two previous efforts by OASIS to create an authorization and authentication protocol, called S2ML and AuthXML. These efforts were being carried out by separate camps, but the SSTC decided it was in everyone's best interests to get all of the camps under one spec and combined the two efforts, because they handled two separate functions. What does pass for Web-based single sign-on is proprietary, the most well known being Microsoft's Passport. SAML is meant to be vendor neutral and is based on XML encoding rather than ASN.1 protocol, which is used in other areas of network sign-on and permissions, such as LDAP. For various reasons, people are gravitating toward using XML rather than ASN.1, according to Hodges. One reason is that XML is textual while ASN.1 is compiled into a binary language. The Web world to a fair degree expects things to be textually based, he said. Another reason is the knowledge level out there. There's a lot more available in terms of learning for XML over ASN.1. SAML is designed not only for user logon to a system, but also for automated B2B transactions that require a secure transaction between the two parties. Again, the automated services run the same as the manual, human-driven functions. The connecting party gives the authorization to access the system and specifies the tasks it can perform -- in this case, a data exchange..." See: (1) the Security Assertion Markup Language website; (2) references in "Security Assertion Markup Language (SAML)."

• [March 22, 2002] "State of the Union." By Daniel F. Savarese. In XML Magzine Volume 3, Number 2 (March 2002), pages 18-24. Cover story. ['XML data and Java logic form a partnership that is growing ever deeper -- take a tour of XML-related specs for the Java platform.'] "In the past year or two, the Java platform has been criticized for lagging behind competing platforms in integrating with XML, and Sun Microsystems has been accused of deliberately dragging its feet to adopt XML as part of its distributed computing strategy. Whatever truth there may have been to those appraisals, it is evident that XML is of strategic importance to the continued evolution of the Java platform and that in a short period of time Java has become an ideal environment for developing XML-based applications. In fact, the inroads XML has made into the Java platform are too numerous to account for completely. Here, we'll take a tour of the places in the Java platform that XML is or will be used and that merit developer attention... Without parsers, schema validators, and high-level APIs for applying XML to specific uses such as messaging and object serialization, developing XML-based applications becomes rather burdensome. XML did not catapult into the limelight of application development because many of these elements did not exist initially and took time to develop. Even though the potential synergy between XML and Java was touted from early on, it was on the backs of other programming languages that XML began its steady climb to the summit of cross-platform computing. Although many independent efforts produced Java-based XML processing APIs, it was not until March 2000 that a standard API, Java API for XML Processing (JAXP), was released. With that foundation, it was possible for the nearly score of additional XML-related Java APIs to be developed and implemented. [Figure 1] shows an example Web service scenario for a fictional coffee retail chain that makes use of Java APIs for XML to solicit price bids from distributors and provide online ordering for customers. The uses of XML in the Java platform can be divided into two categories: APIs that directly manipulate XML documents or specific schemas and APIs that make incidental use of XML. Table 1 lists most of the APIs in the first category that the Java Community Process (see Resources) is working on. Those in the second category are listed in Table 2. Categorizing some of the APIs is rather subjective, but in general, the APIs in Table 1 provide primitive functionality for processing generic XML documents or documents belonging to a specific XML schema. Those in Table 2 provide a specific functionality other than XML processing through a Java API that happens to produce or use some data in XML. For example, logging has little to do with XML processing, but the Logging API allows logs to be formatted as XML records... [Schema Manipulation. These are Java APIs that manipulate XML or specific schemas: SR-5/JSR-63 Java APIs for XML Processing (JAXP); JSR-31 XML Data Binding Specification (JAXB); JSR-67 Java APIs for XML Messaging (JAXM); JSR-93 Java APIs for XML Registries (JAXR); JSR-101 Java APIs for XML-based RPC (JAX-RPC); JSR-102 JDOM 1.0; JSR-106 XML Digital Encryption APIs; JSR-110 Java APIs for WSDL; JSR-157 ebXML CPP/A (Collaboration Protocol Profile/Agreement) APIs for Java.]"

• [March 22, 2002] "Stay in Sync While on the Go." By Jeff Jurvis. In XML Magzine Volume 3, Number 2 (March 2002), pages 52-53. ['Use the common protocol SyncML to pass text-based updates from one source to the other.'] "... Sponsored by Ericsson, IBM, Lotus, Motorola, Nokia, Matsushita, Openwave, Psion, and Starfish Software, the SyncML consortium organized the work around establishing an open, common language to synchronize compliant devices, applications, and services running over any network. SyncML is designed to work over HTTP; Wireless Session Protocol (WSP) for wireless Web applications that run over Wireless Application Protocol (WAP); OBEX (an object exchange protocol that runs over infrared and Bluetooth connections and that is built into most operating systems); lower level TCP/IP; and e-mail protocols such as SMTP, POP3, and IMAP. SyncML uses XML to encode commands and data and is designed to run on top of tried and true Web protocols such as HTTP, SSL, and WAP, and therefore is compatible with the applications developed for Web-friendly mobile platforms such as J2ME. A developer looking to add synchronization capabilities to a mobile app needs only the bare minimum tools... The SyncML language is supported by a corresponding SyncML framework that lays out the architecture for a complete end-to-end cross-platform synchronization solution that encompasses nearly all mobile, desktop, and server data sources, but even the SyncML consortium does not aim to override existing end-to-end single platform solutions. Microsoft's ActiveSync technology works great across Windows platforms and will likely stay proprietary. But look for Microsoft to join Palm, IBM, the major mobile phone manufacturers, and the rest of the world in providing hooks to SyncML for those ever-so-common instances where proprietary devices need to talk to each other..." [Note: the SyncML Data Synchronization Specifications and SyncML Device Management Specifications advanced to version 1.1 in February, 2002. The release of the version 1.1 specifications began a 45-day review period; specifications are subject to change prior to final approval (expected) on Tuesday, April 2, 2002.] See "The SyncML Initiative."

• [March 22, 2002] "Java Architecture for XML Binding (JAXB): A Primer." By Tai-Wei Lin. From [Sun] Java Developer Connection. March 13, 2002. "This article introduces you to the basics of Java Architecture for XML Binding (JAXB) Early Access Implementation v 1.0. You will learn a few basic uses of the API and tools that the EA v 1.0 provides. This paper provides brief explanations on how to create simple binding codes using the API and tools. In addition, this paper also discusses a few situations where JAXB shows its strengths, and is intended for developers who have working understanding of the Java programming language, are familiar with XML, and interested in getting a brief introduction to JAXB. Introduction to JAXB Java Architecture for XML Binding (JAXB) provides an API and tool that allow automatic two-way mapping between XML documents and Java objects. With a given Document Type Definition (DTD) and a schema definition, the JAXB compiler can generate a set of Java classes that allow developers to build applications that can read, manipulate and recreate XML documents without writing any logic to process XML elements. The generated codes provide an abstraction layer by exposing a public interface that allows access to the XML data without any specific knowledge about the underlying data structure. In addition to DTD support, future versions of JAXB will add support for other schema languages, such as the W3C XML Schema. These features enable the JAXB to provide many benefits for the developers..." See: "Java Architecture for XML Binding (JAXB)."

• [March 22, 2002] "Java Web Services Developer Pack Part 1: Registration and the JAXR API." By Ed Ort. With contributions from Ramesh Mandava. From [Sun] Java Developer Connection (February 28, 2002). ['This first article in a series on the Java Web Services Developer Pack shows you how to use the Java API for XML Registries (JAXR) API to publish and search for Web services in a registry.'] "You will find the following topics covered in this article: (1) An Introduction to Web Services; (2) Web Services Technologies [XML, UDDI, SOAP, ebXML]; (3) Java Technologies and Tools for Web Services; (4) JAXR [Clients and Providers, JAXR Packages, JAXR Example]... This article is the first in a series that describes the Java WSDP. The series highlights the technologies and tools included in the Java WSDP, and shows how you can use those technologies and tools to build Web services and applications that access Web services. This first article focuses on registration, in particular, the JavaTM API for XML Registries (JAXR) API, an API in the Java WSDP that you can use to register a Web service. Later articles in the series will focus on other components of the Java WSDP. However before describing JAXR, let's look at some fundamental technologies that drive the Web services model -- especially those that are specifically pertinent to registration. The Java technologies in the Java WSDP support these fundamental Web services technologies. For example, the JAXR API can be used to access standard registries such as those that conform to UDDI or ebXML. A business can use the JAXR API in a Java program to register its Web services in a standard registry, or search for Web services that are registered in standard registries. [...] This article focused on one of the Java APIs in the Java Web Services Developer Pack: JAXR. This API enables you to request Web service registration operations in the Java platform. The article showed how you can use the JAXR API to register a Web service in a standard business registry such as a UDDI registry. It also showed how you can use the API to search a registry for Web services. Later articles in the series will focus on other components in the Java WSDP, and illustrate how you can use them to access and use Web services in the Java platform."

• [March 22, 2002] "Deploying Web Services on Java 2, Enterprise Edition (J2EE)." By Qusay H. Mahmoud and [with contributions from] Ramesh Mandava. From [Sun] Java Developer Connection (March 08, 2002). "The Java Web Services Developer Pack (Java WSDP) is an all-in-one download containing key technologies to simplify building of Web services using the Java 2 Platform. JWSDP is a collection of tools and APIs developed by Sun, and other members of the Java community, that allow you to build Web services quickly and easily. The J2EE platform has established itself as the platform of choice for building multi-tiered enterprise applications and has been adopted as the preferred platform for developing enterprise information systems because of its flexibility and scalability. Deploying web services on the J2EE platform is a natural extension. The Java WSDP components can be integrated with the Java 2 Platform, Enterprise Edition (J2EE), and they can be run on J2EE. The SQE team has come up with guidelines for integrating and deploying web services on J2EE 1.3.1. This article: (1) Presents an overview of Web Services; (2) Shows how to set up the J2EE environment for web services; (3) Shows how to integrate Web services with J2EE; (4) Shows how to deploy sample web services on J2EE; (5) Shows how to run web services on J2EE. [...] This article showed the step-by-step instructions for configuring the J2EE SDK 1.3.1 so that web services can be deployed on top of it. The integration process involved copying some JAR files from JWSDP to J2EE, and configuring port numbers and setting security permissions. The rest of the article showed how to deploy sample web services that come with the JWSDP, on the J2EE platform."

• [March 22, 2002] "Content Repository for Java Technology API." Java Specification Request #170. Specification Lead: David Nuescheler. This JSR "specifies a standard API to access content repositories in Java 2 independently of implementation." Supporting this JSR: Laird Popkin, 3path, Remy Maucherat, Dirk Verbeeck, ATG, Day Software, Deloitte Consulting, Hewlett-Packard, IBM, Nat Billington, Oyster Partners, SAP Portals, Software AG. Description: "The API should be a standard, implementation independent, way to access content bi-directionally on a granular level within a content repository. A Content Repository is a high-level information management system that is a superset of traditional data repositories. A content repository implements "content services" such as: author based versioning, full textual searching, fine grained access control, content categorization and content event monitoring. It is these 'content services' that differentiate a Content Repository from a Data Repository. Many of today's (web) applications are interacting with a content repository in various ways. This API proposes that content repositories have a dedicated, standard way of interaction with applications that deal with content. This API will focus on transactional read/write access, binary content (stream operations), textual content, full-text searching, filtering, observation, versioning, handling of hard and soft structured content... Today, (web) applications have to adapt to every vendor's proprietary API to interact with content repositories. This has the negative effect of locking a large percentage of information assets in vendor specific formats, limiting access to information, impacting system evolution/migration, and availability of third party content management tools. This API will examine solutions to these and other issues deemed important by the expert group. There is no easy way to integrate content-producer-applications (CMS) and content-consumer-applications (CRM, Personalization, Portal, etc.) independently of the actual underlying content repository. The expert group will examine solutions to this problem also... The Content Industry has defined a number of specifications on a protocol level to exchange content (ICE, WebDAV, etc.). However, there is no specification on an API level that addresses the unique requirements of a Content Repository. As well, there exists no Content Repository centric standard that appears to address issues such as version handling, full-text searching, and event-monitoring in a coherent manner... Proposed functional areas: (1) Granular Read/Write Access: This is the bi-directional interaction of content elements. Issues with access on a property level and not just on a 'document' level should be examined. A content tran