I've just found out that the applet version of KGS's client hangs when closing windows, when running in Firefox on my Ubuntu Natty. I have the details below. Fortunately, the Web Start version works without problems, and I am using it, so I am not affected by this problem. I want to put the details up anyway, in case it turns out I'm not the only one with this issue.

So, I have mostly vanilla install of Ubuntu Natty (11.04) 32-bit on a somewhat old laptop (that nevertheless hasn't had these sorts of problems before). I have the latest version of Firefox from the software updates, and I decided to install the latest version of Oracle's Java by hand for various non-go related reasons. That Java install is why I wrote mostly vanilla above. All the other relevant software has come from the standard software repos.

I made an install that is practically equivalent to these instructions:

http://www.wikihow.com/Install-Oracle-J ... untu-Linux

(the page also has a link to the files I downloaded and installed)

Particularly, I made a symlink from the /usr/lib/mozilla/plugins directory to the libnpjp2.so shared object from the Oracle binary package. The plugin works, obviously enough, because I can log in to KGS. I've now tested this several times and while logged in to KGS, the hanging problem is repeatable and always happens the same way. (I've only used guest accounts so far.)

Which is to say, when I close the main window to log off, or a game window to stop watching a game, the whole applet hangs. It becomes non-responsive and I have to close the Firefox tag for the windows to go away. This happens both with the Close button inside the window and the little cross icon in the corner. The smaller dialogs or windows like the Welcome message and Game rules do not cause this when closed.

I don't normally use any other Java applets on a regular basis, so I cannot tell if any others have issues like this. I could try them if you can point me to some interesting applets, though.

Again, the Web start version works fine just like it did before with an earlier version of Java. I've never had the applet hang before either on other systems or other versions of Java. So, I suspect the problem has to do with the version of Java, and possibly the computer, I am using, but I cannot easily test it with Java 1.7 on any other computer right now. (Well, I'd hate to mess with installing it and possibly uninstalling another version.)

Perhaps someone here can test this on their computer with Java 1.7 and the plugin?

Wms: if I can provide you with any more relevant info, let me know. I'll be around here, even though I don't post often.

H'm, I use ubuntu 11.04 too, and don't see this. Then again one of my systems can't run the applet at all for no reason I can understand.

More joy. I discovered that if I use the libnpjp2.so from the JDK directory as the plugin (symlinking again), Firefox crashes when I visit this page:

http://javatester.org/version.html

(It's just supposed to display the Java version you are using.)

If I use the .so from the JRE directory (which I did previously), it works, though the applet still hangs at KGS as before. And apparently these two files are exactly the same, or so the cmp command says...

I suppose I'd better be happy with the fact that at least everything I need to work does work, and use the Web Start client from now on.

Just FYI, I'm also on Natty, and don't have these problems (though there is still a sound issue that I work around by using aoss).

Well, thanks for confirming the problem has something to do with my computer and isn't repeatable for others. I suppose I can let the matter rest for a while, though I will report to wms if I find any reasonable explanation for the problem that would be useful for him to know.

The Firefox crash I wondered about earlier was caused by the plugin not being able to start the Java VM. You apparently have to make the symbolic link to the shared object that is in the correct directory and not the wrong one, though why they'd put a copy of the .so in the wrong place in the first place is still a little mysterious.

(And the right place would be the jre/lib/i386 subdirectory of the JDK or the lib/i386 subdirectoryin the JRE, but not the lib/i386 subdirectory of the JDK.)

Apologies for not being more helpful. Please post if you find a solution.

I have the same problem.

I'm using 64-bit Arch Linux, Firefox 6.0, JRE 7 (both latest Version from the Repositories).
http://javatester.org/version.html reports "Java Version: 1.7.0 from Oracle Corporation"

I logged in in KGS as guest, opened a random game as observer, then tried to close the game window. The window didn't close and there's no further response from the game window or the KGS main window...

EDIT: Same problem with Windows 7 64-bit, using latest JRE from Oracle website, tested with both Chrome and Firefox (32 bit). So it doesn't seem to be system related at all...

EDIT2: I just wrote a very simple applet: Just one label outputting the Java version to make sure I use 1.7.0, one button that opens a JFrame, and in this window a button that closes the window again. With that, I'm not able to reproduce the problem, so it must be something specific to KGS (which doesn't necessarily mean it's KGSs fault, but at least it seems the problem should be fixable on the KGS side).

judicata: No apology is necessary.

flOvermind: Can I have a copy of your test program? I'd like to make sure it doesn't hang on my system either.

I have little to add at the moment, but I did find the behavior was the same using the Opera browser on my Linux laptop, so it is probably due to the applet (or the plugin). I also found that the player info window, too, fails to close, hanging the applet.

So, I'm pretty sure it is the main window, board windows and the player info that crash. The welcome dialog does not. It is possible to log in to KGS with the same guest account immediately after having it hang and closing the tab, so the problem doesn't seem to leave the login active.

EDIT: The room list window also caused the applet to hang when I closed it the last time I tried. I removed the part where I said it does not, because it now did.

Sure.

It's of course not very polished, just a quick hack

Thank you. I could open several windows at the same time and close them without any issues.

EDIT: I should also add that the latest 1.6 JRE does not show this behavior. With the plugin from 1.6.0_27 in use, I could close board windows and player infos without any problems.

What I did was temporarily install it and link the library as the plug-in, while hiding the full JDK 1.7 install by changing its path, as well as the path to its deployment info. That is $HOME/.java/deployment on my system. I think it can mistakenly report that you are using Java 1.7 if you keep the deployment files from the 1.7 install around while using the earlier version.

Javatester.org also said I was using the 1.6.0_27 version, so at least on my system I've now managed to isolate the problem to 1.7 pretty certainly. I can also test Java 1.7 on another system (Windows XP) soon, so I'll report on it after I get around to it.

(But you don't need to worry that I'll keep updating this thread often after that. I won't disturb you with daily reports, I promise. )

Summary time. For some people, Java 1.7.0 browser plugin makes the applet hang, and for some it does not. At least for me, the problem is specific to version 1.7.0, and does not appear with the earlier version of Java that I tried (as I wrote in the previous message).

On the two computers I tested, I had similar behavior in both cases. The applet starts normally and allows me to log in, but when I close a major user interface window, such as a game board or player info, or the main window, the applet hangs. The windows never close and the last displayed view remains visible, but naturally does not update anymore. I can still resize them, but no other functionality remains responsive.

This happens on both the newest Ubuntu 32-bit and Windows XP 32-bit (with latest updates and service packs) in similar fashion. The behavior does not appear to depend on the browser in any way, but is due to the applet. It does not appear with the Web Start client.

Enabling tracing and logging from the Java Control Panel (you can run it as jcontrol from command line, or from an icon in the Windows System Tray) does not add useful information. It does confirm that the connection to KGS is closed after the applet hangs, and the applet has to be cleaned up and closed by the Java Virtual Machine later, because it does not close itself properly.

I am not going to post these logs, because they are full of stuff about class caches and nobody wants to read lines and lines of those. I *can* provide a log if someone thinks they can find useful info from there. And OK, I probably should post the relevant bits anyway, but they are not on the computer that I am at currently. (I will edit this part later and add them.)

The simple Java applet posted by flOvermind does not hang despite opening and closing multiple windows. There is something more complex going on in the KGS client that causes the problem, in connection with the 1.7.0 plugin.

I'll try out java 1.7 and see how it goes. Hopefully I can reproduce the problem.

Java as a GUI sucks. Every new release adds new bugs.

that's why I never upgrade