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Foreword: Excuse me for
possible mistakes. English is not native language for me.
In this issue:
Hello dear friends!
Why does not exist "JavaNotFoundException"?
When I deliver my Java program to
customers often Java is not installed on theirs machines. Having such exception
I could in better form (GUI popup, for example) inform my customers about the
Answer: Is not it obvious
that to be able to find the absence of Java with Java program you need Java
Java wimps please close your ears ... For
the Java programmer who
thought he knew everything there was to know about
Java, have a
look at the most advanced Java newsletter archived on the
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Question: I am sure that in my program I create 100 new
threads and when I use isAlive method it shows often less than 100 threads... I
have not killed even one of them!
Answer: Good, short and clear explanation I found in
Java tutorial on SUN's site:
"The API for the Thread class includes a method
called isAlive. The isAlive method returns true if the thread has been started
and not stopped. If the isAlive method returns false, you know that the thread
either is a New Thread or is Dead. If the isAlive method returns true, you know
that the thread is either Runnable or Not Runnable. You cannot differentiate
between a New Thread or a Dead thread. Nor can you differentiate between a
Runnable thread and a Not Runnable thread."
Question: When I use Java to write my program under
some specific OS, I always set some environment variables to control the
application program. For example, CLASSPATH.
What is about other variables
that I should be aware of? And how can I set them?
Answer: Java defines own environment which is
different from the default one provided by the underlying OS.
define your own "environment" by using
Latest posts on our
|bloking Java plugin in applet tog
How can the default call of the
java plugin on the applet tag be blocked so an applet can be run without the
plugin. I have an applet that runs fine with out the plugin but stalls with
|Almost no hair left! NullPointerException in
I get this error after app has
been running a while.
What is the problem and where can I fix? It doesn't
happen on my dev machine, but only on the production system.
Help will be
|Java Web Start
I have a problem with An
Application that is launched by
I would like to load
class-files from jar's or zip-files that are
not part of the spec. in the
I can download the jar from a web-server and
place the jar's/zip's in a catalog. And then try to instance the classes that i
want from the jars/zips.
I have tried to write my own class-loader. And it
works ok if
i run the application locally ( not from web-start ).
|Watch Training Video on Enterprise JavaBeans For Free(DSL
We just posted new
Training Video on Enterprise JavaBeans(DSL version),it may be helpful for you
|Help in JTextPane
I am displaying a
html file in JTextPane, When I do changes in that file, click on send, These
changes should be sent to other user which highlighted text which is changed, I
know the highlighting part, but how to send only the changes which have been
made, I don't know. I have implemented DocumentListener but I don't know why it
is not responding when I attach a HTMLEditor kit with JTextPane
|JPanel on top of another JPanel
I've got two JPanels. And I
want to show one on top of the other:
The red one has to be
on top of the big bleu JPanel.
I've tried JLayeredPane() already, but that
Does anyone has got an idea how to fix this problem.
Hi again, ne wday new problem.
I have a GUI that takes the attributes for a student, name, address etc and
stores it to a random file. I everything works fine, but now I have to be able
to update the information in the file. When I veiw the student information in
the studentpanel, I should be able to edit the textfields and click on an update
button that will update the file. I don`t want to append on to the existing
file, I just want to overwrite it with the new information...at least thats what
I think it should be doing.
I created my update button and Now I am in the
process of figuring out the actionevent for it,,,,except I do not have a clue, I
havn`t even been able to find any basic examples of this.
This is what I
have so far.
if (e.getSource() == jbtUpdate)
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