Question about using threads and synchronizing objects

Hi all,
I am not that familiar and I have 2 questions.
QUESTION 1
I have a server which just sits and accepts incomming connections, then I spawn off a new thread which implements Runnable, and then call the run method. But the loop would not iterate, it would just sit inside the run method (which has rather long loop in it). I changed the class to extend Thread and called the start() method, rather than run(), and everything worked out fine.
Anyone know why this is?
QUESTION 2
So I am building a client server chat application where a user can be in multiple chat rooms. I have this personObject which has output/input streams. In the personObject, I create writeObject/ readObject method, which simply does as it implies.
I figured that I should make these methods synchronized, to ensure things run smoothly. however, when I made a call to readObject, which sat there and waited, and then made a call to writeObject, I would not enter the writeObject method. I took out the synchronized on the writeObject, and everything worked out fine.
I was under the assumption that synchronizing a method only synchronized on that method, not on the whole class. How come then was I not able to enter the writeObject method?
The more I think about it, I don't think I need to have these methods synchronized, but I thought it wouldn't hurt.
Thanks for the help.

Hi all,
I am not that familiar and I have 2 questions.
QUESTION 1
I have a server which just sits and accepts incomming
connections, then I spawn off a new thread which
implements Runnable, and then call the run method.
But the loop would not iterate, it would just sit
inside the run method (which has rather long loop in
it). I changed the class to extend Thread and called
the start() method, rather than run(), and everything
worked out fine.
Anyone know why this is?
You should still implement Runnable, rather than extending Thread. Like this: Runnable r = new MyRunnable();
Thread t = new Thread(r);
t.start(); run() is just another method. Nothing special about it as far as multithreading or anything else goes.
start() is the method that actually spawns a new thread of execution.
I was under the assumption that synchronizing a
method only synchronized on that method, not on the
whole class. How come then was I not able to enter
the writeObject method?When you synchronize, you obtain a lock. As long as you hold that lock--until you exit the sync block or call wait()--no other thread can enter that block or any other block that obtains the same lock.
Two synchronized methods on the same object rely on obtaining the same lock--there's one lock for each object.

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import java.lang.*;
import java.io.*;
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thread.start();
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I was going to explain what to do, but a quick Google informed me that there's a new class which is designed to help in these situations SwingWorker (or as a [separate library|https://swingworker.dev.java.net/] if you're not up-to-date yet).

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Lets say I got 2 classes, Midlet A and Thread B.
I created Thread B because web services (jsr-172) uses networking and It has to be done in a separate thread other then the Midlet A.
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I really don't understand what's the problem. I've tried various ways to only call getSomething() when the thread finishes running, but all of them made my WTK emulator hang at the part where it asks for permission to access the network.
If I don't use getSomething(), which is the purpose of starting the thread in the first place, it runs fine in the emulator and doesn't hang anywhere. Oh the irony.

Bump!
Anyone got even half a clue what's wrong? =O
Hmm. I think that having the midlet wait for the thread causes the midlet to hang because the thread will then wait for the midlet for permission to access the network, but the midlet is waiting for the thread to finish it's code. Damn.
Message was edited by:
lonereaction

Questions about Using Lightroom and Print Studio Pro

I want to use Print Studio pro via the lightroom plugin since as I understand it, that is the only way to ensure a 16-bit file is being passed to the printer (on Windows). However, I am a little confused about how the image is being rendered. Is lightroom applying a default output sharpening to the file before handing it off to Print Studio Pro or Does Print Studio Pro manage resolution and Output sharpening based on the media and print size you choose?
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Moderator Note; Message Subject edited
Message Edited by andyP on 10-08-2008 07:24 PM

hi
you can try acronis true image solution it will even back up the entire service partition for you!goodluck!
Cheers and regards,
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●๋•کáŕádhí'ک díáŕý ツ
I am a volunteer here. I don't work for Lenovo

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Edited by: Sotnem2k1 on Apr 1, 2008 7:50 AM
Edited by: Sotnem2k1 on Apr 1, 2008 7:51 AM

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hi all
i have a question about using Runtime.getRuntime().
if i use this to get a runtime reference to run an
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Hi, I have quick question about use of USEBEAN tag in SP2. When I specify a scope of SESSION for the java bean, it does not keep the values that I set for variable in the bean persistent.Thanks,Sonny

Make sure that your bean is implementing the serializable interface and that
you are accessing the bean from the session with the same name.
Bryan
"Sandeep Suri" <[email protected]> wrote in message
news:[email protected]..
Hi, I have quick question about use of USEBEAN tag in SP2. When I
specify a scope of SESSION for the java bean, it does not keep the
values that I set for variable in the bean persistent.Thanks,Sonny
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Message was edited by: eww

Question about using threads and synchronizing objects

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