Newbie question concerning java chat

Hi everyone,
I'm going to program at chat-service in java at school. Since I'm still rather new at this game, I was wondering if anyone knew any good tutorials to start with. I'm also very interested in recommendations as to which java techniques would be best.
My initial thoughts on the project are:
1) it's going to be controlled by a central server (using servlets and JSP).
2) I wish to overcome problems concerning firewalls etc.
3) I took a peek in the book "Java Servlet Programming". It said that there were 3 possible implementations: HTTP, Sockets and RMI. I wonder if there are any other possibilities? JMS for instance?
4) I wish to implement the service in such a way, that different users can approach the service differently (eg. user A with HTTP, and user B with RMI). this should be completely transparent. But is that possible?
Well, thats basically all. I hope someone have some tips or experiences to share. I doubt that I'm the first (or the last) one embarking on a project like this.

I've found some links in previous posts.
http://www.javaworld.com/javaworld/jw-01-1997/jw-01-chat_p.html
And the section on "Java Shared Data Toolkit"

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a la
http://javarevisited.blogspot.com.au/2011/04/top-10-java-serialization-interview.html
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a la
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Indeed, however, with a distinct lack of success with the instrumentation api, my request is dualfold now.
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hi,
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T

I think I can answer your Q1
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Just read elsewhere with similar problem. Try putting single quotes around the item in your URL that contains spaces.
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Thanks to all for the help in advance

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I have some questions concerning developing Web Services in java. I understand the basic technology and concepts, but am not familiar with the available Java pieces to accomplish what I need to.
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1. There are 3 ways i can think of:
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b. JWSDP
c. 1.3 IDE with Web Services support (WebShere, Sun One...)
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3. Partly answered in 1... I prefer working with 1.4, because that is a new standard coming up, so no serious changes will be needed later.
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4. wscompile, etc. can be invoked by tools like ant based on your build file, or by IDE.
5. Automatically done...
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HTH,
Reshat.

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We have 48 versions of JRE running in on XP IE6 in our company.
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It's a mess.
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I saw some posts on changing the JRE dynamically or perhaps using a wrapper with a product from "sourceforge".
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Thanks in advance

We have 48 versions of JRE running in on XP IE6 in
our company.
Some version beat up other JAVA applications.
It's a mess.can you elaborate on how some versions "beat up" other apps?
How can anyone manage this many versions?you don't, each computer should periodically upgrade (IMO) but you shouldn't care. if you do, tell your users to load the latest version
Can we consolidate down to a few versions?sure
I saw some posts on changing the JRE dynamically or
perhaps using a wrapper with a product from
"sourceforge".
Are these viable?i have no idea what this is, but I have doubts about your problem, if it exists at all

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My next newbie question:
The following two classes are in two separate files in the same a folder testClass2:
package JavaDemos.testClass2;
import java.awt.*;
public class Sketcher {
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^
1 error
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Why isn't widthXXX directly accessible from
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Newbie question concerning java chat

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