Moderator (MDR): MDR-lisa
Guest Speaker (SPK): SPK-name
MDR-lisa: Hi, everyone! This is Lisa Stapleton, editorial
director of the JDC, and I'm here with Georges Saab, our JavaSoft AWT expert.
Feel free to start sending your questions now. The first release of the
Swing/Java Foundation Classes (JFC) has just been shipped to a limited group of
licensees and partners, so if you have questions about Swing or JFCs, Georges
is the man to ask. So, Georges, what is the relationship between Swing and the
Java Foundation Classes?
SPK-Georges: Well Lisa, I'm glad you asked ;-) Java Foundation
Classes is an umbrella term for a group of new classes and services that
started with JDK 1.1. The Delegation Event Model, for instance, was a large new
chunk of funtionality that was included in 1.1, and is a part of the JFC. Swing
is the set of components, written in 100% Java, which provide an alternative to
the AWT component classes.
creme: I would like to know when Swing will be
shipped to everyone?
SPK-Georges: Swing will be a part of the JFC released with JDK
1.2. However, we're trying to make sure that we get as much feedback as
possible for the Swing APIs by doing developer releases. Depending on the scope
of the feedback that we get from the early access reviewers, we plan to release
to the general public through the JDC in the next month or so.
whitteng: I'm trying to work with drawImage. I'm
trying to draw a complete image into an image buffer and I'd like to know what
the drawImage returns and if drawImage will ever iterate if the source image
it is drawing is complete.
SPK-Georges: drawImage returns true if the image was loaded
and painted successfully and false otherwise. It won't `iterate' as such on
its own. But I'm not the best person to ask about drawImage. I'd suggest that
you send that question to java-awt@java.sun.com so that Jim Graham can get a
shot at it.
Dumbrill: What parts are defined as being in the Swing set
and what other parts are in the JFC, but not considered to be part of Swing?
SPK-Georges: Basically, Swing is the set of components, and
the parts of the services that are 100% Java (like keyboardUI and retargettable
actions). The parts of the JFC that are not in Swing are the things that
require native code, such as drag and drop, custom cursors, and so on.
werpu: Will the JFC also include some sort of
lightweight windows like the IFC had?
RipeauS: Will Swing replace lightweight components?
creme: What is the content of the Swing? What are the
new components?
MDR-lisa: Georges is going to try to answer these related
questions all together.
const: Will .PNG image format be supported in JDK
1.1.x or JDK 1.2? This question is a bit related to Java2d because currently
supported image formats do not fully support alpha channel.
SPK-Georges: I guess you are referring to InteralFrames, which
can be used for MDI (Multiple Document Interface) types of GUIs? They will be
included in the complete component set, but aren't included in the EA release,
which we shipped last Friday.
MDR-lisa: That's a good Java 2D question, const, and Georges
isn't comfortable answering for them, but I will forward the question on to
that group, if you send me email to lisast@eng.sun.com.
SPK-Georges: PNG is unlikely for 1.2, but I can't give you a
definative answer -- the best thing to do is send mail to
java2d-comments@java.sun.com so that someone in the Java 2D group can give you
a more definate answer.
whitteng: Does this mean that Swing does not use
"peers"? Also, when is Swing/JFC/1.2 likely to appear in Netscape and
IE browsers so that we can plan development strategies?
SPK-Georges: Swing does not use peers, that is one of the
great things about it... Also, since it is 100% Java, it can be downloaded and
used seperately from the JDK. It currently runs on 1.1.2, which means that
once it is released, it will be able to be used in any browser supporting JDK
1.1.2 or later.
irsan: Swing components sound really good, but what
about their performance? Won't they be very slow compared to native components?
SPK-Georges: It turns out that one of the major performance
bottlenecks is the constant calling back and forth between Java and native
code. By doing all the drawing of components in Java, much of this is
eliminated, so the performance is quite good.
Dumbrill: Any idea what the time frame will be from
the early release of the Swing components to the early release of the native
code parts of the JFC?
SPK-Georges: The native parts require a new JVM (to have the
native code linked in), so they will be included in JDK 1.2.
werpu: Will there be changes in existing AWT classes
(Dialog for example) in JDK 1.2 and maybe in JFC?
SPK-Georges: There will be changes to existing components in
1.2 to fix bugs that have been reported. Swing is currently `sed-compatible'
with AWT, meaning that it should be possible to run a sed script over most
code, which will allow it to run with Swing. For instance, Button is called
JButton in Swing, and supports the same methods, and some new ones!
const: What does "MVC arch." mean in
description of Swing? Will be there changes in usage scenarios comparing to
current native conponents like TextArea.
SPK-Georges: The internal architecture of a Swing component is
a modified version of Model-View-Controller, a popular method of breaking down
GUI components. As a component user, you don't have to know anything about
this. If you care, however, it is possible to get in under the hood and
manipulate the models of components. This is also an important part of how we
implemented the pluggable look and feel for Swing.
rickl: The layout manager model has one limitiation
that I hoped would be improved. Right now, components can be asked minimumSize
and preferredSize. What I would like to see added is a hint. This would be a
dimension passed to the component, indicating the best space available. Right
now, if a component is variable in height because of width (i.e. wrapped text),
it's impossible to safely do this. Are there any plans along this line?
SPK-Georges: You can also supply a getMaximumSize. In Swing,
we've added two layout managers, which I think people will really like. One is
a Springs-n-struts type manager, and the other is a BoxLayout along the lines
of TeX glue.
const: RichText component is mentioned on Swing WWW
page. Will it be allowed to embed other components in rich text? Will it
support full HTML and RTF or only subset of them?
SPK-Georges: You can embed other components in the RichText
component. Both RTF and HTML will be supported in the final version (I can't
swear to which version of HTML). In fact, the parser is fairly seperate so it
should be pretty easy to modify the component to handle other document formats
JoeSam: I have a JDBC/ODBC inquiry application with
multiple rows and a scrollbar. I would like to have standard pagedown/up
functionality for the scrollbar. Is there a way to get keyboard input to the
scrollbar without adding listeners to the > 50 components on my frame?
Generally, under JDK 1.1, can keyboard and mouse events be captured and
observed prior to the component with the focus?
SPK-Georges: InputEvents are handled a little bit differently
from other events. You might try setting a listener on the Frame itself. If
that doesn't work, a good pattern is to create one listener, cache it, and add
it to your rows as they are created. This reduces the overhead of creating
listeners since you only ever create one.
const: Will the contents of RichText be a separate
entry like String in TextArea or can RichText be constructed only inside
RichText component?
SPK-Georges: The data in a rich text component can be
manipulated seperately from the component itself, if you so choose.
ehorvath: We're having problems loading images in
Netscape vs. Explorer in our applets. Netscape won't load JPEG files, and the
GIF files lose considerable resolution. (The JPEG files will load locally, but
fall apart once they are loaded on the server. Explorer does not have this
problem.) Will this problem be solved in JDK 1.2?
SPK-Georges: You should probably take that up with the browser
companies themselves (they often rewrite code according to our APIs). If you
have a problem with these things in Appletviewer, then the problem lies in our
implementation, in which case, you should send mail to
java2d-comments@java.sun.com
MDR-lisa: Thanks, everyone. It is time to signoff now. And
thank you, Georges.
