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* DB/C Newsletter *
* April 1999 *
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News and Comments
Java performance has always been an issue, whether real or imagined.
In the last couple of weeks, IBM released a Java Virtual Machine (JVM) that
they claimed was the fastest available for Windows. It is also available for
most IBM operating systems. A week later, Sun announced the release of the
HotSpot JVM which they claimed is faster than the new IBM JVM. Various
claims have been made about how wonderful the performance is - for example
"performance is similar to that of C++". We will be checking these claims
in the next few weeks and reporting our results to you in an upcoming issue
of this newsletter.
DB/C JX 2.0 was released this month. GUI support and a source program
debugger are two important new features of JX 2.0. With this release, DB/C
JX is now approaching DB/C 9.1 (and DX) in capabilities and ease of use.
And with the performance boosts of the new JVMs, its speed is approaching
that of traditional DB/C.
DB/C DX 10.0 beta testing continues. Unless some major problems are
found, we will release it this May.
We are continually updating our web site (www.swc.com). We recently
added a Frequently Asked Questions page to the DB/C area. It contains an
accumulation of FAQs found in past issues of this newsletter. Although
there aren't any new FAQs in this newsletter, you don't need to check the
web site for new ones - we'll first publish new Q&As here before adding
them to the web page.
This month's article deals with several related technologies in the
area of document formats. Although they may seem mundane, these technologies
are quite important to many application systems - and they will become more
important in the near future. Let me know if and how you are using any of
these technologies.
don.wills@swc.com
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Document Formats
The number of three letter acronyms (TLAs) used in the computer industry
continues to grow, particularly in the world of document formats. Here are
just a few TLAs (plus some FLAs) used in connection with document formats:
PDF, DOC, RTF, XLS, HTML, XML, XSL, TIFF, GIF, and JPEG.
In this article, we'll discuss the use and future of three document
formats - PDF, HTML and XML.
The Portable Document Format (PDF) is a creation of Adobe Systems. It
was created in the early 1990's in response to the need for a PostScript-like
page description language that could be used interactively and for printing.
The Adobe Acrobat family of software products was introduced to handle all
aspects of creating, displaying and printing PDF files. Initially, Adobe
charged for all Acrobat software. This slowed its acceptance quite a bit.
After Adobe wised up and started giving away Acrobat Reader (the program
used to display and print PDF files), the usage of PDF files took off. It is
widely used today for many documents, from marketing literature to books. All
new DB/C reference manuals are available in both printed form and as PDF files.
PDF's unique capability is that it faithfully reproduces the exact look
of a page - regardless of the output medium. That is, a page looks the same
on the screen as when it's printed. Both text and image reproduction work
well even when the destination isn't optimum. For example, a document may
contain fonts which are not available in an environment, so Acrobat Reader
chooses available fonts that are the closest matches. Because of this, the
page looks as it supposed to look - headlines look fine, lines break at the
same place, and italics and underline work. Graphics and images are also
faithfully reproduced, regardless of pixel resolution or lack of colors.
The future of PDF looks bright. Adobe has recently released Acrobat 4
which adds many new features. Looking at their product plans, it appears that
Adobe plans to make PDF the primary document format for all of their products,
relegating PostScript to final printing only.
The Hypertext Markup Language (HTML) was invented by Tim Berners-Lee as
a little hypertext language for text documents only. Formatting was mostly
ignored. Then Marc Andreesen added the ![]()
tag when he released the Mosaic
browser. Usage of the Internet grew exponentially and HTML grew along with it.
HTML serves a very different purpose than does PDF. HTML documents
contain formatting suggestions, not requirements. For example, a headline in
an HTML page is specified like this:
The Headline
On one browser this may display as 16 point Times Roman; on another it may
display as 24 point Helvetica. End users can even change the headline font
to suit their taste.
Today HTML documents consist primarily of text, images, hypertext links
and forms. Forms are the data entry fields, radio buttons, list boxes and
push buttons that are used in many web pages. HTML is literally the basis of
most Internet commerce. Companies like amazon.com could not have come into
existence without the widespread use of HTML.
XML is a new document formatting language. The XML acronym stands for
the Extensible Markup Language. There is some confusion about XML. Many
people think of XML as a replacement for HTML. It isn't.
XML is actually a meta-language that defines the syntax for a variety of
other languages. XLL and XSL are XML languages that could replace HTML. SPDL
is an XML language that could replace PDF.
However, it is our view that none of these XML-based languages will
replace PDF and HTML in the near future. Usage of PDF and HTML document
formats will continue to grow for the next few years because they are adequate
and they are in general use. XML doesn't provide better capabilities for what
PDF and HTML are meant to accomplish.
XML will be used extensively in another area - Electronic Data Interchange
(EDI). In combination with a Document Type Definition (DTD), XML can be used
to define any structured data. In the past, EDI has largely been dominated
by Value Added Network (VAN) providers. These VANs are proprietary, closed
systems that provide both software and communications facilities. We believe
that the VANs will be replaced with XML-based languages and communication via
the Internet. One such example is the RosettaNet initiative in which IBM and
Microsoft are the primary partners.
In summary, we predict these document format standards will continue to
grow for the next several years:
1. PDF for documents that need exact reproduction
2. HTML for web pages including forms data entry
3. XML based languages for EDI and data exchange documents
So what does this all have to do with DB/C?
In the area of HTML, if you are interested in writing a CGI-based web
server application using DB/C 9.1 or DB/C DX, check out the January 1997 DB/C
Newsletter for information. Or if you want to write your server application
with another tool, you can use DB/C FS to access your data stored in a DB/C-
based filesystem.
PDF support will be added into a future release of DB/C DX and DB/C JX.
This support will be provided by the spool open and print statements of DB/C.
We are looking closely into XML-based EDI, but don't have any specific
DB/C related plans at this time.
Here are some useful web links:
for PDF: http://www.adobe.com/acrobat
for HTML: http://www.w3.org/TR/REC-html40
for XML: http://www.w3.org/XML
http://www.software.ibm.com/xml
http://www.xml.com
http://www.geocities.com/WallStreet/Floor/5815/xmlindex.htm
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DB/C Class Schedule
Class: DB/C DX and JX Language Fundamentals
Date: June 1999 (the exact date is not yet determined)
Location: Oak Brook, Illinois
For information, contact Judi Tamkevic at:
voice 630.572.0240
email dbc@swc.com
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