TweetFollow Us on Twitter

May 00 Online

Volume Number: 16 (2000)
Issue Number: 5
Column Tag: MacTech Online

May 00 Online

By Jeff Clites <online@mactech.com>

A few months ago, we briefly touched on the subject of XML, the biggest hype magnet since Java. A quick glance at any IT-related publication or website will give you a pretty good idea of the degree of interest there is in anything related to XML, and companies are churning out press releases about their plans to utilize XML faster than the press can cover them. XML isn't the Next Big Thing, it's the Current Big Thing. No matter where you stand on the hype-versus-substance issue, as a developer you'll need a working understanding of the technology to meet the demands of new standards and new modes of application interoperability. Beneath the static there is great potential in XML, and everyone will benefit from the attention it is drawing to issues surrounding communication and standardization. This month we'll cover a few of the resources you can turn to when working with this rapidly growing technology.

Documentation

Although there are many choices available, it is difficult to find the perfect printed reference; many of the obvious choices turn out not to be very good, and the field is evolving so rapidly that even the high-quality books quickly become out-of-date. For the moment, though, there are a couple of winners. The XML Pocket Reference, from O'Reilly and Associates, serves as both a beginner's introduction and a quick reference. For an extensive survey of current (and developing) technologies and APIs, try Professional XML from Wrox Press.

XML Pocket Reference
<http://www.oreilly.com/catalog/xmlpr/>

Professional XML
<http://www.wrox.com/Consumer/Store/Details.asp?ISBN=1861003110>

There is also no end to web-based coverage. An indispensable source is the XML FAQ, which covers a wide range of topics, and is well written. At the other end of the difficulty spectrum is the XML specification itself. Although you'll want to avoid it as long as possible, at some point you'll need to go back to the source to get the definitive word on something. It's a difficult read, but there is a cleverly-constructed annotated version available, which makes deciphering the formal language a bit easier. This latter reference is provided by XML.com, which is an excellent source of references and ongoing coverage of the industry, with timely articles on emerging technologies. Next, the XML Cover Pages are an exhaustive and neutral reference for all things XML (and SGML) related. Also of general interest is the original "mission statement" of the XML standard, which sets forth the design goals for its development. Finally, those planning on developing or working with XML parsers should take a look at the Lark parser, developed by Tim Bray, co-editor of the XML specification. It does not appear to be under active development, but it does provide an interesting case study in parser development in Java.

The XML FAQ
<http://www.ucc.ie/xml/>

The Annotated XML Specification
<http://www.xml.com/pub/axml/axmlintro.html>

XML.com
<http://www.xml.com/pub>

The XML Cover Pages
<http://www.oasis-open.org/cover/xml.html>

Design Principles for XML
<http://www.textuality.com/sgml-erb/dd-1996-0001.html>

An Introduction to XML Processing with Lark and Larval
<http://www.textuality.com/Lark/>

Programming XML

XML was designed to be easy to parse, and XML documents are often characterized as self-describing, but if you need to develop an XML-processing application you'll quickly find out that this is nonetheless not a trivial job. Fortunately, there are a number of parsers out there to help you with this task, and simple XML documents can in fact be created and parsed simply. One of the first XML parsers, and perhaps the most widely used, is James Clark's expat. It's a non-validating parser written in C, and recently an Objective C wrapper has been created for it, so it should be straightforward to use it from within Cocoa applications. (I believe that expat is also being used internally within Mac OS X, but it isn't clear what sort of API Apple will provide to access it.) Moving forward, it is likely that the Xerces parsers, which are part of the Apache XML project, will be widely used. They are validating parsers, and are available in Java, C++, and Perl. Much of their code originated from IBM's alphaWorks project, and IBM continues to provide its own versions, XML4J and XML4C for the Java and C++ versions respectively, which combine Xerces with their own Unicode classes, providing support for an expanded range of encodings. Apple is in fact using XML4J in their recently-released version 4.5 of WebObjects, and again it isn't clear to what extent the parser will be accessible from other parts of Apple's frameworks. Xerces-C contains a fair amount of code which must be customized when porting it to new platforms, but a classic Mac OS port has been developed, and a BSD version is in development which is likely to compile under Mac OS X. Also of note is the gnome-xml parser, which is under active development. It falls under the umbrella of the Linux Gnome project, but it is independent of the rest of Gnome and should be portable to other environments and platforms. (For example, it is known to work under Windows.) It is also a validating parser, but appears to be simpler than Xerces and may be worth a look if you need to access a validating parser from C and related languages. The gnome-xml web page also has links to several other articles to get you started, and in particular you should take a look at the article on IBM's developerWorks site.

expat - XML Parser Toolkit
<http://www.jclark.com/xml/expat.html>

Objective C wrapper for the expat XML Parser
<http://softrak.stepwise.com/Apps/WebObjects/Softrak.woa/1/wa/displayPackage?package=815&os=10>

The Apache XML Project
<http://xml.apache.org/>

IBM's XML Parser for Java (XML4J)
<http://www.alphaworks.ibm.com/tech/xml4j>

IBM's XML for C++ parser (XML4C)
<http://www.alphaworks.ibm.com/tech/xml4c>

The XML library for Gnome
<http://xmlsoft.org/>

Making application programming easy with GNOME libraries, Part 3
<http://www-4.ibm.com/software/developer/library/gnome3/>

If you're experimenting with XML for the first time, or you need to process XML in a web-related context, you should check out the numerous Perl modules available. A good place to start is the libxml-perl package. Of particular interest are the XML-Grove modules, which let you manipulate an XML document as a tree of objects and access various parts of it using a path-like syntax. This is analogous to the DOM and XPath APIs, and the grove interface will likely become obsolete after these have matured, but in the short term it provides a convenient and powerful approach to XML processing. There are a number of other APIs available for working with XML documents from Perl, including DOM-based and SAX-based parser APIs (the former allows you to access XML documents as a tree of objects, and the latter as a stream of events), as well as support for various approaches to XML querying. IBM has two excellent articles which are not to be missed; one gives a brief run-through of all of the XML-related Perl tools available, and the other gives a detailed tutorial on manipulating XML using Perl, including conversion of XML to HTML and XML-driven database access.

libxml-perl
<http://bitsko.slc.ut.us/>

Essential tools and libraries for using XML with Perl
<http://www-4.ibm.com/software/developer/library/perl-xml-toolkit/>

Manipulating XML documents with Perl and other scripting languages
<http://www-4.ibm.com/software/developer/library/xml-perl/>

When you grow weary of mucking around with the innards of the future web, cruise on over to the MacTech Online web pages at <www.mactech.com/online/>, and let you browser worry about the parsing for a while.

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

How to become the ultimate robot warrior...
Chrono Strike is a delightfully immersive beat ‘em up with a sense of humor (any game with a good Sims reference gets points in my book). [Read more] | Read more »
Tips and tricks to get a higher score in...
Snow Roll is a devilish endless runner very much in the vein of Flappy Bird. It revels in its dastardly level of difficulty, and doesn’t really care how angry you get at it as it knows you’ll keep coming back for more. [Read more] | Read more »
How to win big in Slots Deluxe
Cheating while gambling is illegal and morally wrong, and in some parts of the world it leads to men with names like Vinnie "Six Knuckles" Manchenzo beating you to a pulp in a dark alley. [Read more] | Read more »
How to take over the world in Dictator 2
Running a country isn't easy - especially when you're a dictator who wants to take over the world and crush everyone in your path while you do it. [Read more] | Read more »
Tips and tricks to get a higher score in...
Tank.iois - you guessed it! - another multiplayer arena battler likeAgar.io and Slither.io. It does differentiate itself by putting you in a tiny tank though, so it's not exactly the same. To help you get that all-important high score, we've got a... | Read more »
How to unlock characters in One Tap Tenn...
As the title suggests, One Tap Tennis requires only a single tap to play its particular brand of tennis, and rewards you with a ton of unlockable characters if you perform well. Fortunately for you, we at 148Apps have got a few tips and tricks to... | Read more »
Grab it now: Game Craft’s Legend of War...
The real time strategy game is now available for you to sink your teeth into, through the App Store and Google Play. Combining elements of skill, strategy and empire building, Legend of War is a real gamers’ game. [Read more] | Read more »
Skateboard Party 3 ft. Greg Lutzka (Gam...
Skateboard Party 3 ft. Greg Lutzka 1.0 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0 (iTunes) Description: Skateboard Party is back! This third edition of the popular sports franchise features professional skater... | Read more »
Cubious (Games)
Cubious 1.0 Device: iOS Universal Category: Games Price: $.99, Version: 1.0 (iTunes) Description: Cubious – How smart are you? How high is your IQube? Solve the impossible puzzles to find out, and help a lost little cube find his... | Read more »
Goat Simulator Waste of Space (Games)
Goat Simulator Waste of Space 1.1 Device: iOS Universal Category: Games Price: $4.99, Version: 1.1 (iTunes) Description: ** IMPORTANT - SUPPORTED DEVICESiPhone 4S, iPad 2, iPod Touch 5 or better.** | Read more »

Price Scanner via MacPrices.net

Enterprise Workers Pick Technology Over Perks...
New Adobe study shows surprising attitudes about office jobs and where the future of work is heading. Adobe has released survey findings revealing that a surprising 70 percent of U.S. office workers... Read more
Memorial Day Weekend Sale: $50-$100 off 11-in...
B&H Photo has 13″ and 11″ MacBook Airs with 256GB SSDs on sale for $50-$100 off MSRP. Shipping is free, and B&H charges NY sales tax only: - 11″ 1.6GHz/256GB MacBook Air: $999 $100 off MSRP... Read more
Memorial Day Weekend Sales: Apple MacBook Pro...
B&H Photo has 13″ and 15″ Retina MacBook Pros on sale for up to $210 off MSRP. Shipping is free, and B&H charges NY tax only: - 15″ 2.2GHz Retina MacBook Pro: $1799 $200 off MSRP - 15″ 2.5GHz... Read more
Memorial Day Weekend Sales: Apple iMacs and M...
Take up to $150 off the price of a new iMac or Mac mini at the following Apple resellers this Memorial Day weekend: iMacs: B&H Photo has 21″ and 27″ iMacs on sale for up to $150 off MSRP... Read more
Apple refurbished Retina MacBook Pros availab...
Apple has Certified Refurbished 2015 13″ and 15″ Retina MacBook Pros available for up to $380 off the cost of new models. An Apple one-year warranty is included with each model, and shipping is free... Read more
Apple refurbished 11-inch MacBook Airs availa...
Apple has Certified Refurbished 11″ MacBook Airs (the latest models), available for up to $170 off the cost of new models. An Apple one-year warranty is included with each MacBook, and shipping is... Read more
Goal Zero and OtterBox Partner to Expand iPh...
Goal Zero, specialists in portable power, have announced a partnership with OtterBox, brand smartphone case protection, to offer the Slide and Slide Plus Batteries as modules compatible with the new... Read more
15-inch Retina MacBook Pros on sale for up to...
B&H Photo has 15″ Retina MacBook Pros on sale for up to $210 off MSRP. Shipping is free, and B&H charges NY tax only: - 15″ 2.2GHz Retina MacBook Pro: $1799 $200 off MSRP - 15″ 2.5GHz Retina... Read more
Clearance 2015 13-inch MacBook Airs available...
B&H Photo has clearance 2015 13″ MacBook Airs available for $250 off original MSRP. Shipping is free, and B&H charges NY sales tax only: - 13″ 1.6GHz/4GB/128GB MacBook Air (MJVE2LL/A): $799... Read more
Apple refurbished Apple TVs available for up...
Apple has Certified Refurbished 32GB and 64GB Apple TVs available for up to $30 off the cost of new models. Apple’s standard one-year warranty is included with each model, and shipping is free: -... Read more

Jobs Board

*Apple* Architect - AECOM (United States)
**Requisition/Vacancy No.** 132759BR **Position Title** Apple Architect **Job Category** Information Technology **Business Line** Government **Country** United Read more
*Apple* Solutions Consultant - APPLE (United...
Job Summary As an Apple Solutions Consultant, you'll be the link between our future customers and our products. You'll showcase your entrepreneurial spirit as you Read more
*Apple* Project Engineer - Smart Source Inc...
SmartSource is in need of an Apple Project Engineer for a 12 month contract opportunity in Pittsburg, PA. Role: Apple Project Engineer Location: Pittsburg, PA Read more
Automotive Sales Consultant - Apple Ford Linc...
…you. The best candidates are smart, technologically savvy and are customer focused. Apple Ford Lincoln Apple Valley is different, because: $30,000 annual salary Read more
Service Assistant - *Apple* Chevrolet *App...
Apple Automotive is one of the fastest growing dealer...and it shows. Consider making the switch to the Apple Automotive Group today! At Apple Automotive, we Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.