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<title>Book Review: Netscape IFC in a Nutshell LG #28</title>
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<H4>
"Linux Gazette...<I>making Linux just a little more fun!</I>"
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<h1><font color="maroon">Book Review: Netscape IFC In a Nutshell</font></h1>
<H4>By <a href="mailto:celestinor@acm.org">R. J. Celestino</a></H4>
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<P> <HR> <P>
<ul>
<li>Authors: Dean Petrich and David Flanagan
<li>Publisher: O'Reilly and Associates
<li>E-mail: <A HREF="mailto:info@oreilly.com">info@oreilly.com</A>
<li>URL: <A HREF="http://www.oreilly.com/">http://www.oreilly.com/</A>
<li>Price: $19.95 US
<li>ISBN: 1-56592-343-X
</ul>
Netscape quietly released its Internet Foundation Classes (IFC) in the
spring of 1996. This free Java class library offers developers a welcome
alternative to the lifeless GUI widgets and basic graphics provided in
Sun's Abstract Windowing Toolkit (AWT). However, the IFC can be
intimidating even for experienced Java developers. To effectively use the IFC, you must
learn its event model and its container model, both of which differ
from standard Java. Additionally, learning the IFL's
classes and API is no small endeavor. <i>Netscape IFC in a Nutshell</i>
helps, with good explanations, examples and a handy quick reference guide.
<p>
<i>Netscape IFC in a Nutshell</i> is written by Dan Petrich and
David Flanangan. In the Nutshell tradition, it is not too big or
intimidating. The cover graphic will surely lead IFC geeks to refer to
it as ``the fish book''. It weighs in at around 350 pages, approximately
140 pages of which are the quick reference section. This same reference
information is available in HTML format from Netscape. I think it is
helpful to complement on-line documentation with a compact hard copy
reference, and I'm sure we all agree that making notes in the margin of
an HTML page can be a bit difficult.
<p>
The book is far more than an API reference. It
takes you through the IFC classes in a logical and matter-of-fact
manner. Numerous examples cover most of the important aspects of the
IFC. The examples are typically small but effective. They are well focused
on the topics at hand and help immensely with understanding.
The book does not include a CD-ROM, which is too bad as it would make a
nice addition to the book. As an alternative, O'Reilly and Associates could
have provided space on their web site for on-line examples and running
applets. Unfortunately, they didn't do that either, so be prepared to
type in each example and code fragment by hand.
<p>
The authors begin with a high-level introduction to the IFC. They discuss
its capabilities including the sophisticated GUI widgets, persistence
mechanism and the visual construction tool <i>Constructor</i>. If you
are not sure what the IFC is all about or if it's right for you, this
section is very helpful.
<p>
The next topic is an introduction to the most basic class in the IFC,
the Application Class. As an IFC user, I have noticed that the IFC often
departs from traditional Java vernacular. The Application class is one
example of many you will come across. Seasoned Java developers typically
understand <i>application</i> to mean a stand-alone Java program,
and <i>applet</i> to mean a restricted Java program that runs in a
browser. Forget all that when using the IFC. Every running IFC program,
be it stand-alone or applet, is an application. Don't worry though;
it's all explained very simply in this chapter using the power of the
venerable <b>Hello World</b> program.
<p>
Having straightened out what an application is, the book takes you
through a good explanation of the IFC's View classes. View classes in
the IFC are akin to the Container classes in standard Java, but with
differences in both architecture and capabilities. The authors devote
three chapters to a discussion of these classes. They make good use of
examples to show you many of the important features, from tiling a
bitmap on the background to drawing.
<p>
Users interact with GUIs using a mouse and keyboard. In Java, these
devices make themselves known by generating <i>events</i>. The mechanism
by which these events are made available to your program is known as the
event model. The Java standard event model has evolved over its short
lifetime. It began as an inheritance-based model, eventually maturing to
the more powerful delegation-based model used today. The IFC uses a hybrid
model. The chapter on mouse and keyboard events covers the inheritance-based model. The chapter on targets covers the IFCs implementation of
delegation-style event handling. The details of using each type of event
are discussed in reasonable detail. Numerous examples show how to code
your own event processing. However, I felt that the authors should have
contrasted the two styles better. In addition, it would be helpful if
they offered some guidelines on when to use each model.
<p>
The book moves on to cover each widget in considerable detail. Remember
that the IFC provides a replacement for every standard widget, so even
items as simple as a push-button or text field have a new API. These
chapters really drive home the power of these IFC widgets, making the
traditional widgets from Sun look absolutely bland.
<p>
I found their treatment of scrolling particularly useful. The IFC
provides a framework to support scrolling of text and graphics. While
very powerful, understanding the details can be daunting. The authors
present scrolling clearly and offer good illustrative examples. With
the details in this chapter, you will be able to add scrolling to any
application with ease.
<p>
Another excellent section is the one on layout managers. Layout managers
are classes that help View classes decide upon the size and position of
the widgets they contain. The IFC includes a powerful new layout manager,
the PackLayout. The book covers this complex layout manager in excellent
detail. Outside of this book, there is virtually no useful documentation
on the true behavior of the pack layout.
<p>
Anyone who has ever written an applet that displays images will
eventually reach the conclusion ``why don't they handle all of this mess
for me?'' Netscape's engineers felt the same way, and they did something
about it. In the chapters on images and animation, you will learn how
simply your application can read and display image files (both GIFs and
JPEGs). Creating animation is a simple matter as
well. The book explains how the IFC handles threading, sequencing and
double buffering. If you are interested in images and animation,
these chapters will get you going quickly and painlessly.
<p>
In the <i>Advanced Topics</i> section, the authors cover the details of
the TextView class, archives, and the free GUI builder Constructor.
<p>
The authors rightly spend a considerable amount of time discussing the TextView
class. They show how to use TextView to display
HTML documents, handle hyperlinks, open a mini editor and more. With all
this versatility from a single component, it is a comfort to have clear
explanations and examples to lead you.
<p>
The authors next discuss archives. Archives provide object
persistence. Every class in the IFC can be archived to disk so that it
can outlive the process that created it. The authors detail how to use
IFC archives to read and write objects in a number of situations. They
also discuss how to archive existing IFC classes and explain how
to archive classes that you have created.
<p>
Finally, you will learn how to use Netscape Constructor. Unlike the rest
of the IFC, Constructor is an application not a component. Perhaps
this is why the chapter is so skimpy. Considering this chapter is
in the ``Advanced Topics'' section, I would have expected more detailed
information. Nonetheless, the chapter does provide some good information
on few aspects of the elusive Constructor.
<p>
The GUIs that are created using the IFC are truly a pleasure to
behold. The widgets, in stark contrast to their plain Java brethren, have
a polished look and feel. Some of the components, such as TextView,
are so powerful that they could be marketed on their own. Learning such
a comprehensive class library can be downright scary.
<i>Netscape IFC in a Nutshell</i> provides numerous easy to follow examples,
detailed explanations and a quick reference guide.
<p>
Eventually, the IFC will be subsumed by the Java Foundation Classes (JFC),
a joint venture between Sun and Netscape. But if you want beautiful
user interfaces today, the IFC is the way to go, and <i>Netscape IFC in a
Nutshell</i> is a great way to get you there.
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<center><H5>Copyright &copy; 1998, R. J. Celestino <BR>
Published in Issue 28 of <i>Linux Gazette</i>, May 1998</H5></center>
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