The information presented here is by no
means complete nor is it organized. I just wanted to present some perspective
on the component software as to spur enough interest for reader to look
futher into this issue.
As noted by the famous Byte article ( May
1994 / Cover Story / Componentware ) one of the first widely known
uses of component technology was VBX, or Visual Basic Controls (eXtensions?).
Many applications are using the plug-in technology to allow 3-rd party
developers to expand on the application's functionality. It started with
import-export file format filters and developed in some cases into full-blown
component architectures. Among the first mainstream applications using
plug-ins was Adobe Photoshop. Another widely known example is Netscape
Navigator/Communicator with hundreds of plug-ins that support various
data formats. One may want to note Illustrator, PageMaker, Premier, Acrobat
from Adobe; QuarkXPress; Freehand,
Director, X-Res from Macromedia;
CorelDraw, CorelPaint from Corel.
SOM by IBM is a veteran componentware
product. By reading the IBM article on SOM (IBM's
System Object Model (SOM): Making Reuse a Reality) one can't help but
note many similarities between rationales of COM and SOM. Purists would
ask, who was the first ?(IBM was), pragmatics would ask, who makes money
out of it (you bet the answer is Microsoft, but it is a wrong answer, no
one actually does).
An artifact of Apple's vision on the component software (Apple
DU: ICS: Component Technologies), an OpenDoc
is a great example of how a well-designed and carefully implemented software
system could go into maturity and be buried by mismanagement, lack of marketing
focus, or maybe just mere insufficient funding.
A major player in the component software field, the CORBA effort is undertaken
by the Object Management Group. Use this
link: What IS CORBA????
to satisfy your curiosity about the abbreviature. Comparing
ActiveX and CORBA/IIOP is biased, of course, but worth reading anyway.
There are many high-end products based on the CORBA technology. Looks like
there is enough "beef" in CORBA to spur the interest of serious people.
One of the patterns authorities, Douglas
Schmidt quotes CORBA as one of his research
JavaBeans is a recent entry
into the world of component software. It may finally deliver on the promise
its precedors made. Barely a year-old, JavaBeans is already supported by
virtually all development tool vendors and by most major Java developers.
walking tour of JavaBeans - JavaWorld - August 1997 is a good overview
on the technology.
JavaBeans is often considered a competitor to ActiveX (like in JavaBeans
Takes On ActiveX). In a bright move to encourage its supporters, JavaSoft
has demonstrated interoperability
between JavaBeans and ActiveX. Lotus has futher pushed the JavaBeans
technology and came up with the InfoBus technology (JavaBeans
"InfoBus" Draft Specification) which promises seamless integration
between data processing components (yawn).
ActiveX and Security
Speaking about ActiveX one cannot help noticing the ActiveX
security bugs scandal
which spurred a lot of public discontent
Enquiring minds can find a lot of information on component technologies
on the Internet. Take for example a Component-Oriented
Programming page created by Guy Laden email@example.com.