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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: