| Where is my JFrame? (was Strange behavior when trying to debug my application within eclipse) [message #322457] |
Mon, 19 November 2007 07:38  |
Eclipse User |
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Originally posted by: yaronrein.hotmail.com
Hi,
I was able to isolate the problem.to the following program, it runs well
from the command line but fail to show the frame when running within Eclipse
Why does System.in.read(buffer); prevent the frame creation within Eclipse?
Thanks in advance
/Yaron
import java.io.IOException;
import javax.swing.JFrame;
public class WhereIsMyJFrame
{
public static void main(String[] args)
{
new WhereIsMyJFrame();
}
private WhereIsMyJFrame()
{
Thread thread = new Thread()
{
public void run()
{
System.out.println("run");
WhereIsMyJFrame.loop();
}
};
System.out.println("starting the thread");
thread.start();
System.out.println("creating the main window");
JFrame frame = new JFrame("WhereIsMyJFrame");
System.out.println("main window created");
frame.setVisible(true);
}
private static void loop()
{
try
{
byte buffer[] = { 0 };
do
System.in.read(buffer);
while ((char) buffer[0] != 'x');
}
catch (IOException ioexception)
{
ioexception.printStackTrace();
}
}
}
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| Re: Where is my JFrame? (was Strange behavior when trying to debug my application within eclipse) [message #322527 is a reply to message #322520] |
Tue, 20 November 2007 07:13  |
| Eclipse User |
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Originally posted by: akarypid.yahoo.gr
Yaron Reinharts wrote:
> Thank you Alexandros
>
> I don't see this thread in the debug window
> I see other threads, there are all seems to be running (including one which
Yes, this is correct. You will see all threads there as "running", even
though the thread may just be waiting in vain for something to occur.
There is an "interrupt" button which will change the thread's state to
susspended and show you where the thread instruction pointer is at,
along with a stack trace of how it got there.
In order to see meaningful names, call "setName()" on your threads to
give them human-readable descriptions. Then you can know which thread is
what.
> is called AWT-Shutdown)
> I'm using Eclipse Version 3.3.1
>
> Anyway, I found a workaround for my problem (skipping the console reading)
> However, I'm still curious to understand what happened and to know if I
> should do something about it (bug report)
In any case if you _require_ console input, I'm pretty sure you can have
it and still work around this (as described in my previous post) by
having the thread's run() method wait for the JFrame constructor to
return and then access the console.
> Thanks
> /Yaron
>
> "Alexandros Karypidis" <akarypid@yahoo.gr> wrote in message
> news:47429F85.3040509@yahoo.gr...
>> If you debug your application, you'll see that if you interrupt the main
>> thread you'll see it's within:
>>
>> WDesktopProperties.init() line: not available [native method]
>> whereas the other thread is
>>
>> FileInputStream.readBytes(byte[], int, int) line: not available [native
>> method]
>> My guess is that the Swing library somehow accesses the console in
>> WDesktopProperties.init() causing a deadlock. I'd use an object to wait
>> for the frame to become visible before proceeding with console access:
>>
>> public void run() {
>> synchronized (sync) {
>> try {
>> sync.wait();
>> } catch (InterruptedException e) {
>> return;
>> }
>> }
>> // ...
>>
>> and
>>
>> private WhereIsMyJFrame() {
>> // ...
>> JFrame frame = new JFrame("WhereIsMyJFrame");
>> synchronized (sync) {
>> sync.notify();
>> }
>> System.out.println("main window created");
>> frame.setVisible(true);
>>
>> Also, I'd guess that you could reproduce this thing outside of Eclipse if
>> you ran your program from the command line and redirected your standard
>> input and output.
>
>
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| Re: Where is my JFrame? (was Strange behavior when trying to debug my application within eclipse) [message #322725 is a reply to message #322527] |
Tue, 27 November 2007 02:44 |
| Eclipse User |
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Originally posted by: yaronrein.hotmail.com
Thakns again, it was very helpful
/Yaron
"Alexandros Karypidis" <akarypid@yahoo.gr> wrote in message
news:4742CF72.30801@yahoo.gr...
> Yaron Reinharts wrote:
>> Thank you Alexandros
>>
>> I don't see this thread in the debug window
>> I see other threads, there are all seems to be running (including one
>> which
>
> Yes, this is correct. You will see all threads there as "running", even
> though the thread may just be waiting in vain for something to occur.
>
> There is an "interrupt" button which will change the thread's state to
> susspended and show you where the thread instruction pointer is at, along
> with a stack trace of how it got there.
>
> In order to see meaningful names, call "setName()" on your threads to give
> them human-readable descriptions. Then you can know which thread is what.
>
>> is called AWT-Shutdown)
>> I'm using Eclipse Version 3.3.1
>>
>> Anyway, I found a workaround for my problem (skipping the console
>> reading)
>> However, I'm still curious to understand what happened and to know if I
>> should do something about it (bug report)
>
> In any case if you _require_ console input, I'm pretty sure you can have
> it and still work around this (as described in my previous post) by having
> the thread's run() method wait for the JFrame constructor to return and
> then access the console.
>
>> Thanks
>> /Yaron
>>
>> "Alexandros Karypidis" <akarypid@yahoo.gr> wrote in message
>> news:47429F85.3040509@yahoo.gr...
>>> If you debug your application, you'll see that if you interrupt the main
>>> thread you'll see it's within:
>>>
>>> WDesktopProperties.init() line: not available [native method]
>>> whereas the other thread is
>>>
>>> FileInputStream.readBytes(byte[], int, int) line: not available [native
>>> method]
>>> My guess is that the Swing library somehow accesses the console in
>>> WDesktopProperties.init() causing a deadlock. I'd use an object to wait
>>> for the frame to become visible before proceeding with console access:
>>>
>>> public void run() {
>>> synchronized (sync) {
>>> try {
>>> sync.wait();
>>> } catch (InterruptedException e) {
>>> return;
>>> }
>>> }
>>> // ...
>>>
>>> and
>>>
>>> private WhereIsMyJFrame() {
>>> // ...
>>> JFrame frame = new JFrame("WhereIsMyJFrame");
>>> synchronized (sync) {
>>> sync.notify();
>>> }
>>> System.out.println("main window created");
>>> frame.setVisible(true);
>>>
>>> Also, I'd guess that you could reproduce this thing outside of Eclipse
>>> if you ran your program from the command line and redirected your
>>> standard input and output.
>>
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