[2303] in java-interest
java-interest-digest V1 #193
daemon@ATHENA.MIT.EDU (owner-java-interest-digest@java.su)
Thu Sep 28 15:24:53 1995
From: owner-java-interest-digest@java.sun.com
Date: Wed, 27 Sep 1995 15:45:29 -0700
To: java-interest-digest@java.sun.com
Reply-To: java-interest@java.sun.com
java-interest-digest Wednesday, 27 September 1995 Volume 01 : Number 193
In this issue:
Can this be done?
GUI design
Re: Setting Boundaries (was Re: JDK Question)
Re: Sun Java Courses
Re: Q: show/hide an applet
Creating window applications
How to layout Panel items vertically in pre-Beta?
Re: java-interest-digest V1 #190
Books on Java
Spare CPU cycles
template .java file for applets
New versions of my Java FAQ list and tutorial
peek() into a stream lately?
Re: Persistent Objects, Distributed Objects.
[none]
java-interest-digest V1 #191
----------------------------------------------------------------------
From: D.C.Baldaro@reading.ac.uk (D. C. Baldaro)
Date: Wed, 27 Sep 1995 17:21:50 +0100
Subject: Can this be done?
I am trying to develop an interface (hopefully in Java), and would really
appreciate should input on the following:
1) I need to create an interface that will establish a socket connection with
a remote host, and pass data streams down and listen for replies. Does this
create any problems with Java security? The local user is basically sending
preset commands to a remote resource. The remote resource is handled by a
server which is bound to a port number. Hence the reason I need the local
client to be able to establish a socket connection and commnicate via a data
stream.
2) Live audio and video feeds?
Can people please give me some feedback on this. As to what level it can
be achieved, and any references to code.
Thank-you muchly in advance.
Dave Baldaro
Active Robotics Group, The University of Reading
------------------------------
From: James L Weaver/DELCO <JLWEAVER@mail.delcoelect.com>
Date: Tue, 26 Sep 1995 15:24:34 -0500 (EST)
Subject: GUI design
Is there a way to position GUI widgets on a dialog by using coordinates and
sizes (as opposed to using layouts)? It would be nice to use a conventional
dialog design tool, make note of the coordinates and sizes for each widget, and
code them in Java.
Thanks,
Jim Weaver
------------------------------
From: Sami.Shaio@Eng.Sun.COM (Sami Shaio)
Date: Wed, 27 Sep 1995 09:41:16 -0700
Subject: Re: Setting Boundaries (was Re: JDK Question)
There are no native methods in java.awt.*. All the native methods
are done in another package that is platform-specific (or you can
even have multiple awt implementations on the same platform or
runtime).
- --sami
|From daemon@java Tue Sep 26 23:13 PDT 1995
|Date: Tue, 26 Sep 1995 20:44:24 -0400 (EDT)
|From: James C Deikun <jcdst10+@pitt.edu>
|Subject: Re: Setting Boundaries (was Re: JDK Question)
|To: Chuck McManis <cmcmanis@scndprsn.Eng.Sun.COM>
|Cc: java-interest@java.Eng.Sun.COM
|Mime-Version: 1.0
|X-Info: To unsubscribe, send 'unsubscribe' to java-interest-request@java.sun.com
|
|
|
|On Fri, 22 Sep 1995, Chuck McManis wrote:
|
|>
|> Actually, adding more java files doesn't impact portability since they
|> just work. There are currently 28 classes in the java.* hierarchy that
|> have native methods (and thus require porting). Pure java code works the
|> same where ever it runs.
|
|I wonder how many of those native method classes are in java.awt.*.
|
|In any case, a third-party implementation still has to duplicate the
|library code unless it wants to work only in conjunction with the Sun
|distribution, so the libraries still add work that could have an especial
|impact on producers with low budgets.
|
|--
|James "impacted?!" Deikun
|-
|Note to Sun employees: this is an EXTERNAL mailing list!
|Info: send 'help' to java-interest-request@java.sun.com
------------------------------
From: "Jim Farley" <farley@crd.GE.COM>
Date: Wed, 27 Sep 1995 12:36:49 +0000
Subject: Re: Sun Java Courses
> From: George E Crawford <gec2@Ra.MsState.Edu>
> Date: Tue, 26 Sep 1995 12:27:42 -0500
> To: java-interest@java.sun.com
> Subject: Sun Java Courses
>
> OK, I've been unable to find ANY information about SL-230 Basic Java Programming
> and SL-270 Advanced Java Programming (I've tried both the web page and
> the 800 number). Does anyone know specifics about these courses (price,
> location, etc.) or where the I can find the details?
If you talk to a human being at the 800 number, and not just the FAX-on-demand
service, they can send you the course descriptions, dates and locations.
- ------------------------------------------------------------------------------
Jim Farley
GE Research and Development
farley@crd.ge.com
- ------------------------------------------------------------------------------
------------------------------
From: Arthur van Hoff <Arthur.Vanhoff@Eng.Sun.COM>
Date: Wed, 27 Sep 1995 09:46:43 -0800 (PDT)
Subject: Re: Q: show/hide an applet
Hi,
> Question about applet:
>
> 1. Is there a method that show/hide an applet(or Graphics Object)?
Every AWT component implements show() and hide().
Have fun,
Arthur van Hoff
------------------------------
From: "Cristini, Jamie" <Cristinij@segaoa.com>
Date: Wed, 27 Sep 95 10:49:00 PDT
Subject: Creating window applications
Can anyone tell me how to "Hello Word" in a stand alone window, launched
from the Hotjava browser?
------------------------------
From: suresh@thomtech.com (Suresh Srinivasan)
Date: Wed, 27 Sep 1995 14:24:57 -0400
Subject: How to layout Panel items vertically in pre-Beta?
Hi all,
I've been playing with the layout managers (BorderLayout,
GridLayout, etc). Is there an easy way to lay out items vertically
with the existing managers?
For example, in DrawTest.java, I'd like the color palette to laid
out vertically as an "East" component of the applet, yet be
centered vertically.
I first removed the Choice item (Lines/Points) for simplicity.
I tried using GridLayout(6, 1) for the DrawControls class,
but that of course makes the checkboxes 1/6th the height of
the applet.
Then I tried changing the init() method of DrawTest to:
public void init() {
setLayout(new BorderLayout());
DrawPanel dp = new DrawPanel();
add("Center", dp);
DrawControls dc = new DrawControls(dp);
Panel p = new Panel();
p.setLayout(new BorderLayout());
p.add("East", dc);
add("East", p);
}
In other words I create an "East" panel with BorderLayout and add
the controls as *its* "East" item. Now I don't even see the palette.
I apologize if this is something trivial, but would appreciate some help.
Thanks,
- --Suresh
------------------------------
From: Hedley Nicholas <hedley@ucsu.colorado.edu>
Date: Wed, 27 Sep 1995 12:41:11 -0600 (MDT)
Subject: Re: java-interest-digest V1 #190
dear people...
Er..I did not order this service....thanks but no thanks.
Please terminate ASAP
N Hedley
------------------------------
From: "Michael G. Stemmler, EMJ OSG Technician" <mikes@emj.ca>
Date: Wed, 27 Sep 1995 14:38:26 -0400
Subject: Books on Java
Are there any books published as of yet on Java? If so, which
ones (ISBN number, Publisher, Title, etc.)? Which of them are
the best for covering the whole language from beginner to expert?
Any and all info would be greatly appreciated. Thanks.
Mike Stemmler
- --------------------------------------------------------------------------------
Mike Stemmler, EMJ Data, RR6, Highway 24 South, Guelph, ON N1H 6J3
Phone: (519) 837-2444 x 299 Fax: (519) 837-8935 anon ftp soon avail.
email: mikes@emj.ca uucp:..hookup.net!emjhq!mikes http://www.emj.ca(na)
- ----[Accessing The Internet Through FTP Explore OnNet (508) 685-4000]----
------------------------------
From: "Elliotte Rusty Harold" <Elliotte@blackstar.com>
Date: Wed, 27 Sep 1995 14:33:00 EST
Subject: Spare CPU cycles
Recent discussions on this list have gotten me to thinking. There
really isn't any way for a user to prevent java applets from
borrowing excess CPU cycles is there? For instance it would be
possible to write an algorithm to accomplish some highly CPU
intensive and very parallelizable code (like breaking DES), include
the code in a regular animation applet, add some code to send the
results back to the server where I would have a special program to
collect the data, and then place the applet on a popularweb page. This
way I could borrow many CPU cycles from machines all over the net to
crack some very tough problems. As near as I can tell there's nothing
in java that would prevent this since at no time would any of this
violate any of java's security constraints.
In some cases it might be possible to fund or charge for pages
by donation of CPU cycles rather than by advertising or subscription.
Doing this behind people's back is a problem, but there might be
ways for me to point my browser at a page working on a
problem I supported when my machine is idle so I could donate its
memory and CPU cycles to the project without having to trust the lead
scientist absolutely.
There have been a number of problems solved by harnessing the power
of multiple computers working in parallel such as the recent cracking
of Netscape's 40-bit security code and my own work on optimal batting
orders (not the most significant projects I admit). However until now
the lead programmer had to be trusted on all the systems he or she
used. That is no longer true if the code is written in java.
Any thoughts?
- --
Elliotte Rusty Harold Black Star Publishing Co., Inc.
elliotte@blackstar.com 116 East 27th Street
elharo@escape.com NY NY 10016
------------------------------
From: Robert Frost <frost@cdr.stanford.edu>
Date: Wed, 27 Sep 1995 12:15:27 -0700 (PDT)
Subject: template .java file for applets
Does anyone know of a good generic template java file for creating
Pre-Beta applets?
Thanks,
Rob Frost
------------------------------
From: Elliotte Rusty Harold <elharo@inch.com>
Date: Wed, 27 Sep 1995 16:40:07 -0400 (EDT)
Subject: New versions of my Java FAQ list and tutorial
New versions of my Java FAQ List and Tutorial are now available at
<URL:http://www.nymug.org/javafaq.html>
Please look them over and make any comments you may have. Please
note that this URL is VERY temporary. Please do not link to it from
any of your sites, and please save the files if you wish to refer to
them later. They probably won't be there for more than a couple of
days.
- --
Elliotte Rusty Harold
elharo@shock.njit.edu
webmaster@nymug.org
------------------------------
From: rethingt@lehman.com (Russell Ethington)
Date: Wed, 27 Sep 95 16:46:41 EDT
Subject: peek() into a stream lately?
I've been digging through the various input stream classes looking
for a way to peek() at my NetworkClient's serverInput stream without
taking bytes out of it. PushbackInputStream looked promising until I
saw the source (in 1.0Alpha3).
Using mark() and reset() would work, but they aren't implemented for
the SocketInputStream. So, should I:
1) Make a BufferedInputStream from a SocketInputStream and use
mark() and reset()?
2) Write something that extends FilterInputStream, implement peek(),
and override read() to insert a peeked byte when appropriate?
3) Jump out a window because I'm missing something really obvious
and should be programming in Cobol?
There must be a better way than:
public class PeekableStream extends BufferedInputStream
{
PeekableStream(InputStream in)
{
super(in);
}
public int peek()
{
mark();
int it = read();
reset();
return(it);
}
}
Having gobs of fun,
- -r
------------------------------
From: john@anasazi.com (John Moore)
Date: Wed, 27 Sep 95 14:14:05 -0700
Subject: Re: Persistent Objects, Distributed Objects.
Tom Judge writes...
>
>I'm just posting this as food for thought. How about extending
>Java so that is supports.
>
>1) Persistent objects. That is so that you can save an object
>instance and reload it from a URL. This would make back ends,
>databases etc. a piece of pie.
I'd like persistent objects on the Client, so you can create something with
an applet that can be used later on the client (on or off line). It should
have varying degrees of security so it can be shared with other applets, or
kept private, or only shared with certain applets (or classes, or whatever).
As a commercial example, imagine that you apply for an receive an electronic
credit card using the web and a Java-enabled browser. The credit card would
be a Java object that you get from the web site that issues it, and stores
itself on your machine. It is subsequently useable for electronic commerce.
Obviously authorization, permissions, authentication and other security
issues are critical here. For example... other authorized classes should be
able to use it. How do they get authorized? How are they authenticated? What
is the permissions scheme?
I see some very high volume important applications for this sort of thing in
the vertical market my company plays in.
------------------------------
From: Joseph Jones <jones@iwn.com>
Date: Wed, 27 Sep 1995 15:00:41 -0700
Subject: [none]
HI,
I'm pretty new t java, and I was wondering if their were any good =
examples on how to open a window, place a few UI components and accept =
user interaction. (either an applet or a stand alone java app would be =
nice). The API Documentation is fairly scarce on use information.
thanx,
Joe
------------------------------
From: owner-java-interest-digest@java.sun.com
Date: Tue, 26 Sep 1995 23:30:10 -0700
Subject: java-interest-digest V1 #191
java-interest-digest Wednesday, 27 September 1995 Volume 01 : Number 191
In this issue:
problems with animator applet
Re: Java SIG in NYC
Sending an object across the net...
IMPORTANT: Registration information for Java Courses
Re: JDK : layout : is something wrong ?
Re: Ready or not, here it comes...
Re: throws declataration in Java/beta
Resend: Re: Debugging Java
Re: Setting Boundaries (was Re: JDK Question)
Re: regular expressions in Java
Java Progress and the Java team
Java Grammar
Re: throws declataration in Java/beta
Re: throws declataration in Java/beta
Re: Sending an object across the net...
Java VM clarifications
Re: GUI design
- ----------------------------------------------------------------------
From: Dorian Winterfeld <dorian@Glue.umd.edu>
Date: Tue, 26 Sep 1995 19:49:49 -0400 (EDT)
Subject: problems with animator applet
Dear Java Gurus.
I am a novice Java programmer who is struggling to get the new
Animator class to work. I incorporated the following code into my html:
<app class="Animator" img="gifs" pause=0 repeat=true audioloops=true
audio="spacemusic.au">
And tried to view it via HotJava but it doesn't work! Nothing happens.
I created a directory called classes and put Animator.class in it. I
renamed my gifs to T1.gif to T9.gif and placed them in a directory
called gifs. I put the .au file in the same directory as my html.
Am I doing something wrong ? BTW, I compiled Animator.java on ver 1
Alpha3 of HotJava under Win95. Can anyone help me out?
my URL is http://www.wam.umd.edu/~dorian/index.html.
- ------------------------------
From: Andrew Zolli <sgint2@interport.net>
Date: Tue, 26 Sep 1995 19:50:37 -0400 (EDT)
Subject: Re: Java SIG in NYC
On Tue, 19 Sep 1995, Timothy Arnold wrote:
> Hi java programmers,
>
> Well its happening. After getting a very positive response about starting a
> java programming Special Interest Group here in New York City, I'm going to
> proceed on and try to schedule a meeting within a week or so. I'll replay
> the message I posted at wwwac in NYC and let me know if you are interested.
> _______________________________________________________________________________
> Hello wwwac members,
>
> I'd like to start a SIG group centered on programming in Java. In order to
> benefit developers I'd also like to keep it focussed on programming issues
> to help current programmers troubleshoot, figure out semantics, or just get
> started in this new language. My motivation for this is to speed up the
> learning curve and to at least start a network of fellow java programmers in
> NYC which would benifit all of us. If you think you might be interested
> please let me know and I will repost within a week so we can get the ball
> rolling.
>
> Best Regards,
> Tim Arnold
> yimmit@well.com
> ____________________________________________________________________________
> ____
>
> -
> Note to Sun employees: this is an EXTERNAL mailing list!
> Info: send 'help' to java-interest-request@java.sun.com
>
There already IS a Java Users Group in NYC... its first meeting was
announced by Olivia Whiteman at Java Day... If anyone needs info, please
get in touch.
Andrew Zolli
Webmaster,
Siegel & Gale
NYC
- ------------------------------
From: Derek Hamner <dhamner@email.unc.edu>
Date: Fri, 22 Sep 1995 14:34:54 -0400 (EDT)
Subject: Sending an object across the net...
I have written simple client & server based on the sun.net classes and I
would like to know if it would be possible to extend the
DataInput/OutputStream classes to accommodate more complex types. I
would like to be able to send any simple object across the network, and
then reconstruct it on the other side. Is this possible?
Any help or pointers to past discussions on this topic would be greatly
appreciated.
Derek Hamner
UNC-Chapel Hill
- ------------------------------
From: tmcg@blueline.East.Sun.COM (Tom McGinn - SunService Education)
Date: Fri, 22 Sep 1995 15:39:56 -0400
Subject: IMPORTANT: Registration information for Java Courses
***** FOR FURTHER INFORMATION ABOUT REGISTERING FOR JAVA TRAINING: *****
Folks -
Sorry for the confusion. There are two registration phone numbers;
one for International students and one for US students.
International students (Outside of the US) please use call:
(408) 276-3630 for registration information (8 am to 5 pm PST).
or send e-mail with a request for information to: registrars@sun.com
In the US, please call:
(800) 422-8020 for registration information (8 am to 5 pm PST).
Sun Microsystems students should register using e-mail. Please send
e-mail to (no subject required): education@sun.com
- ------------------------------
From: reast@esri.com (Russell East [ESRI-Redlands])
Date: Tue, 26 Sep 95 15:52:23 PDT
Subject: Re: JDK : layout : is something wrong ?
: Hi Jean-Claude,
:
: > I cannot get anything deterministic out of the various
: > layoutManagers. Is something wrong, or is it just me ?
:
: I hope it is just you. If you have a particular problem you'll have
: to attached a simple example. Random muttering doesn't help.
:
: Arthur van Hoff
Maybe you are having the same problem that I am experiencing?
I am using a Solaris 1 machine operating as an X-terminal onto
a Solaris 2 system where all the java work is done. When running
appletviewer (Beta1) or hotjava (Alpha3) on my Sol1 system, if I
drag any window corner out, the layout does not correctly
compensate for the window resize, and the graphics moves all over
the place - if I drag the window size far enough, the graphics
completely disappears.
I don`t get this problem when running on a Sol2 X console, nor on
my NT box operating as an Xterminal. I guess it's time for an
upgrade for me.... :)
Russell.
- - -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
ESRI| | Russell East,
| | Development Programmer E-mail: reast@esri.com
----|---| Environmental Systems Research Institute
| | 380 New York Street Voice : +1 (909) 793 2853
____|___| Redlands, Ca, 92373, USA Fax : +1 (909) 793 5953
- - -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
- ------------------------------
From: Sami.Shaio@Eng.Sun.COM (Sami Shaio)
Date: Fri, 22 Sep 1995 11:14:34 -0700
Subject: Re: Ready or not, here it comes...
A number of us in the Java group have been involved with helping
Netscape do the Java integration. As a result we know exactly what's
going on. To restate what has been said by arthur: *only* the java
applet support has any relation to Java, everything else including
their scripting language has *no* relation. Trust me.
- - --sami
|From phil@bolthole.com Wed Sep 20 18:45:13 1995
|Subject: Re: Ready or not, here it comes...
|To: java-interest@java
|Date: Wed, 20 Sep 1995 11:18:44 -0700 (PDT)
|From: phil@bolthole.com (Philip Brown)
|Mime-Version: 1.0
|Content-Transfer-Encoding: 7bit
|X-Info: To unsubscribe, send 'unsubscribe' to java-interest-request@java.sun.com
|
|[ Glen C. Perkins writes ]
|>
|>
|> I wasn't guessing that the plug-ins were *written* in Java, I was guessing
|> that they could be *driven* from Java. I know they're not written in Java.
|
|You KNOW they are not?
|
|Personally, I was hoping that netscape had put a layer on top of java, to
|create their own "java for idiots" language, that is a cross between java,
|perl, and logo. It would then have hooks to call plugins.
|The plugins would presumably be standalong C-compiled things. Although if
|they are being nice, plugins should also be ALLOWED to be java code as well.
|
|Access to plugins could be done through some security module, like file and
|host access is handled with hotjava.
|-
|Note to Sun employees: this is an EXTERNAL mailing list!
|Info: send 'help' to java-interest-request@java.sun.com
|
- ------------------------------
From: arnold@cocolat.East.Sun.COM (Ken Arnold - Sun Labs)
Date: Fri, 22 Sep 1995 16:04:34 -0400
Subject: Re: throws declataration in Java/beta
>From: Christopher Lindblad <cjl@Eng.Sun.COM>:
> From: arnold@cocolat.East.Sun.COM (Ken Arnold - Sun Labs)
>
> A method cannot throw an exception type not declared in its throws
> clause. This is good. You now know which exceptions can be thrown by
> a method.
>
>Then shouldn't any method that uses the "new" operator be required to either
>catch java.lang.OutOfMemoryError or declare it in its throws clause?...
>
>Also, shouldn't any method that uses arrays or accesses an instance variable
>or method on another object either catch java.lang.NullPointerException or
>declare it in its throws clause?...
>
>Perhaps these should be considered "universal" exceptions, in that one should
>assume that all methods throw them. In that case, shouldn't
>InterruptedException be counted as a "universal" exception too?
You are absolutely correct. In fact, Java has such "universal"
exceptions, such as NullPointerException and OutOfMemoryError. And you
don't have to declare them, since they can happen anytime to any code.
These are all extensions of the RuntimeException class, which do not
have to be declared in signatures.
And, no, InterruptedException is not and should not be one of them,
since it is only of interest to the thread involved. Otherewise
InterruptedException would cause thread death, since an unhandled
exception in run() will result in run() terminating, which stops the
thread. This is probably not the expected behavior.
Ken Arnold
- ------------------------------
From: Thomas.Ball@Eng.Sun.COM (Thomas Ball)
Date: Tue, 26 Sep 1995 16:31:54 -0700
Subject: Resend: Re: Debugging Java
The "use" command (like in dbx) shows the list of directories which
will be searched to find a source file. By default, it uses your
classpath -- that's a poor choice for source files, but it's the only
clue I have (it's been said that Californian==clueless, but that's off
the subject). If you specify a colon-deliminated list of source
directory roots with the "use" command, jdb should have no trouble
looking up source files. Here's part of the path I use:
main[1] use .:/home/tball/java/src/share/java
Note that you only need the top of the source tree if it matches the
class hierarchy, that is, if the package name can be used as part of the
path. For example, jdb would lookup java.lang.String by taking each
path, appending the package, and then adding the source file name
(stored in the class file), so it would try (using the above path):
./java/lang/String.java (not there...)
/home/tball/java/src/share/java/java/lang/String.java (a winner!)
Note: if you are doing remote debugging, specify the source file paths
used on the remote machine. The source files are actually copied down,
so you have some assurance that those are the actual source files.
I'll be adding a way to store the initial jdb setup commands, so you
won't need to always enter them anymore.
Your second problem points to missing features (though soon to be
added). Although you can set breakpoints either by line number or
method name, you can currently only clear them by line number. To make
things more painful, there's no way today to list the current
breakpoints.
The good news is that when you hit a breakpoint in a class which has
line number information (the default), the source file and the line
number of the breakpoint will be displayed in the breakpoint event
message. Here's an example:
running ...
main[1] stop in TicTacToe.mouseUp
Breakpoint set in TicTacToe.mouseUp
Breakpoint hit: TicTacToe.mouseUp (TicTacToe.java:235)
AWT-Motif[1] clear TicTacToe.mouseUp
"TicTacToe.mouseUp" is not a valid id or class name. <== to be fixed
AWT-Motif[1] clear TicTacToe:235
Breakpoint cleared at TicTacToe: 235
AWT-Motif[1] cont
Fixed in the next release, as they say.
Tom
> Hi Thomas ,
>
> I decided to try out some of the java debugging commands using TicTacTac .
> Everytime I do a list to try and see the source code I get a message saying
> "Unable to find $JAVAHOME/demo/TicTacToe/TicTacToe.java" . I am also having
> problems with clearing breakpoints .
> Maybe I'm doing something wrong . Please can you clarify the usage of these 2
> commands . Your help will be most appreciated .
>
> Many Thanks ,
>
> Mushtaq
- ------------------------------
From: James C Deikun <jcdst10+@pitt.edu>
Date: Tue, 26 Sep 1995 20:44:24 -0400 (EDT)
Subject: Re: Setting Boundaries (was Re: JDK Question)
On Fri, 22 Sep 1995, Chuck McManis wrote:
>
> Actually, adding more java files doesn't impact portability since they
> just work. There are currently 28 classes in the java.* hierarchy that
> have native methods (and thus require porting). Pure java code works the
> same where ever it runs.
I wonder how many of those native method classes are in java.awt.*.
In any case, a third-party implementation still has to duplicate the
library code unless it wants to work only in conjunction with the Sun
distribution, so the libraries still add work that could have an especial
impact on producers with low budgets.
- - --
James "impacted?!" Deikun
- ------------------------------
From: cmcmanis@scndprsn.Eng.Sun.COM (Chuck McManis)
Date: Tue, 26 Sep 1995 17:49:41 -0700
Subject: Re: regular expressions in Java
>Several people have pointed out how valuable unicode-savvy regular
>expressions would be to Java, but the Java team never responds to this
>question. I wish they would.
Ok, I'm on the Java team, I don't have a *CLUE* how one could express
a regular expression that would cull Thai and Korean strings from
a generic set of unicode strings.
>Or maybe the answer is, "Not now, not ever, and this is why...." There
>could be a lot of very good reasons. You haven't hesitated to share your
>reasons for not including various other language features.
I think the folks should take silence to mean "Gee, that's an idea amongst
the eight bazillion that we can't just pop off an answer to." It neither
endorses nor condemns the idea. I can also say that it would be MUCH
more productive to have the dialog start with "These are my ideas for
a regular expression syntax to deal with unicode." UNICODE hacking is
an art that, when jumped into lightly, bites one in the more sensistive
parts.
We would LOVE to have an RE languge for UNICODE, but its down somewhere
below the Mac port I believe in priority. (No, I can't tell you when you
can get the Mac port either :-()
- - --Chuck
- ------------------------------
From: MikeDacon@aol.com
Date: Tue, 26 Sep 1995 23:24:01 -0400
Subject: Java Progress and the Java team
Chuck McManis writes:
>>>
I think the folks should take silence to mean "Gee, that's an idea amongst
the eight bazillion that we can't just pop off an answer to." It neither
endorses nor condemns the idea. I can also say that it would be MUCH
more productive to have the dialog start with "These are my ideas for
a regular expression syntax to deal with unicode." UNICODE hacking is
an art that, when jumped into lightly, bites one in the more sensistive
parts.
We would LOVE to have an RE languge for UNICODE, but its down somewhere
below the Mac port I believe in priority. (No, I can't tell you when you
can get the Mac port either :-()
<<<
I'd just like to thank Chuck and the Java team for responding to posts on
this list. I've have seen alot of posts from them lately and appreciate it.
I'd also like to recommend that we all give the Java team a little slack. We
all know that Java has the potential to be something really special. They
know it too and are trying to pull it off. Constructive criticism and
assistance is much more in need now then feature bashing.
When I was in the Army, a golden rule for briefing the commander was that you
never present a problem without giving him three solutions. If we could
follow that, Java development could precede faster.
- Mike Daconta
Mystech Associates, Inc.
- ------------------------------
From: "John D. Mitchell" <johnm@mitchell.org>
Date: Tue, 26 Sep 1995 20:44:40 -0700
Subject: Java Grammar
Proposed Standard
Java Programming Language
Grammar Specification
September 26, 1994
AUTHORS:
Terence J. Parr parrt@parr-research.com
John D. Mitchell johnm@mitchell.org
Gary Funck gary@intrepid.com
OWNERSHIP:
For the moment, we maintain the copyright on this grammar.
REVISION:
1.00 Initial proposal
LOCATION:
This file is located at:
ftp://ftp.parr-research.com/pub/Java/java.g.proposed
NOTES:
This grammar is designed for language specification purposes and is
*not* executable. Its purpose is to define the syntactic structure of
the Java language. Neither PCCTS nor YACC will accept this file as
input. It is most certainly non-LL(k) for any k and probably not
LALR(1) due to context-sensitivity (must use symbol table info to
parse, but due to forward references, one doesn't have that
information). The grammar is much tighter than you'd probably use in
practice; for example, we differentiate between lvalues and rvalues
rather than letting it slide to the semantic analysis phase.
No semantic information is used in this grammar; i.e., we have not
predicated any productions on symbol table information.
It is built from our experience in writing an initial Java front end
using PCCTS. The front end is not yet available. Stay tuned for more
information.
We hope this will facilitate the open discussion of and eventual
standardization of the Java programming language so that we can
all move forward from a safe and sane base and write lots of
truly cool software.
....
- ------------------------------
From: garya@village.org (Gary Aitken)
Date: Tue, 26 Sep 1995 22:09:47 -0700
Subject: Re: throws declataration in Java/beta
>It is very important to realize that a Java class is a guaranteed interface.
>If an method is declared to throw a certain set of exceptions than there is no
>way a sub class can change that. At first this may seem restrictive, but after
>a while you will realize that it is wonderful to have this guarantee.
It's not clear to me what's so wonderful about this guarantee.
There is no similar guarantee that a subclass will not compromise the intended
behavior of its base in numerous other ways. What makes exceptions special?
Gary Aitken garya@village.org
- ------------------------------
From: Arthur.Vanhoff@Eng.Sun.COM (Arthur van Hoff)
Date: Tue, 26 Sep 1995 21:27:49 -0800 (PDT)
Subject: Re: throws declataration in Java/beta
Hi Gary,
> >It is very important to realize that a Java class is a guaranteed interface.
> >If an method is declared to throw a certain set of exceptions than there is no
> >way a sub class can change that. At first this may seem restrictive, but after
> >a while you will realize that it is wonderful to have this guarantee.
>
> It's not clear to me what's so wonderful about this guarantee.
> There is no similar guarantee that a subclass will not compromise the intended
> behavior of its base in numerous other ways. What makes exceptions special?
Exceptions affect the control flow of the caller. While implementing
this feature we found a number of bugs in HotJava were we simply didn't
realize that a certain exception could thrown.
Have fun,
Arthur van Hoff (avh@eng.sun.com)
http://java.sun.com/people/avh/
Sun Microsystems Inc, M/S UPAL02-301,
100 Hamilton Avenue, Palo Alto CA 94301, USA
Tel: +1 415 473 7242, Fax: +1 415 473 7104
- ------------------------------
From: Simon Spero <ses@tipper.oit.unc.edu>
Date: Tue, 26 Sep 1995 21:50:47 -0700 (PDT)
Subject: Re: Sending an object across the net...
On Fri, 22 Sep 1995, Derek Hamner wrote:
> I have written simple client & server based on the sun.net classes and I
> would like to know if it would be possible to extend the
> DataInput/OutputStream classes to accommodate more complex types. I
> would like to be able to send any simple object across the network, and
> then reconstruct it on the other side. Is this possible?
>
> Any help or pointers to past discussions on this topic would be greatly
> appreciated.
>
Not using datainput/output, but... I'm currently working on a compiler
for a subset of ASN.1 generating encoders for the PER and BER. This will
generate objects that can encode and decode themselves, as opposed to
taking arbitrary objects and serialising them (java's reflective
operators are too weak to do this)
Simon
- ------------------------------
From: Nathan Loofbourrow <loofbour@cis.ohio-state.edu>
Date: Wed, 27 Sep 1995 01:16:29 -0400
Subject: Java VM clarifications
Thanks to all for their help in parsing the Java class file format,
esp. C. McManis for his Java-based parser.
I'm seeing a few opcodes for which the alpha3 Java VM docs aren't
adequate. To wit:
1. Opcodes 135 and 255 appear in compiled code (such as the Java
contest winners :-), but isn't mentioned anywhere in the VM spec,
from what I can tell.
2. Opcode 132 is mentioned twice in the spec, once as the i2l type
conversion instruction and once as the iinc increment
instruction. I imagine this relates to #1 above.
Any pointers/corrections?
nathan
- ------------------------------
From: Sami.Shaio@Eng.Sun.COM (Sami Shaio)
Date: Tue, 26 Sep 1995 22:42:37 -0700
Subject: Re: GUI design
Using absolute positioning is not a good idea since different native
implementations will have different sizes for things. You should use
layout objects since they will behave properly when the size of
the widgets varies.
- - --sami
- ------------------------------
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