Never posted here, but been using jEdit for probably 15+ years on linux systems.
Posted similar to this on the 'jedit-users' listserv - not clear whether these forums or the listservs are most appropriate so trying both.

This is on Ubuntu 14.04, which packages openjdk-7-jdk and jEdit 5.1.

On 2018-08-10 there was an upgrade of openjdk-7, specifically to 7u181-2.6.14-0ubuntu0.2, details here:
https://www.ubuntuupdates.org/package/core/trusty/main/updates/openjdk-7-jdk

This openjdk upgrade has broken jEdit - on my xubuntu 14.04 system at least. I was using jEdit as usual before the upgrade. After the upgrade, it fails to fully launch. The splash briefly appears, it runs through some of the launch steps, then vanishes. That's all. Output of running
$ jedit -log=1
...is pasted in below.

I've tried the following, with same results:
- uninstalled (complete purge) and reinstalled 5.1
- clean installs of each of 5.3, 5.2, 5.0, and 4.5.2

So whatever breaks in jEdit vs. the openjdk upgrade, is broken in all of those.
Nothing else I'm aware of in recent OS upgrades would affect jEdit.

I have another system with ubuntu 16.04 on it, which packages openjdk-8 and jEdit 5.3. That is fully updated package-wise and works fine.

Any other ideas for troubleshooting on this 14.04 system welcome.

I imagine upgrading this system to ubuntu 16.04 or higher would fix it but that is not something I can dive into just now...if there's no fix for my particular situation other than that I'll have to live without jEdit for a while.

I don't know if these older jEdit versions are being maintained vs. issues like this. If they are I'll submit a bug.

regards,
John S.


Log output follows...

------------------------------------

$ jedit -log=1
2:37:26 PM [main] [message] Log: When reporting bugs, please include the following information:
2:37:26 PM [main] [message] Log: java.version=1.7.0_181
2:37:26 PM [main] [message] Log: java.vm.version=24.181-b01
2:37:26 PM [main] [message] Log: java.vm.name=OpenJDK 64-Bit Server VM
2:37:26 PM [main] [message] Log: java.runtime.version=1.7.0_181-b01
2:37:26 PM [main] [message] Log: java.runtime.name=OpenJDK Runtime Environment
2:37:26 PM [main] [message] Log: java.vendor=Oracle Corporation
2:37:26 PM [main] [message] Log: java.compiler=null
2:37:26 PM [main] [message] Log: os.name=Linux
2:37:26 PM [main] [message] Log: os.version=3.13.0-155-generic
2:37:26 PM [main] [message] Log: os.arch=amd64
2:37:26 PM [main] [message] Log: user.home=/home/john
2:37:26 PM [main] [message] Log: java.home=/usr/lib/jvm/java-7-openjdk-amd64/jre
2:37:26 PM [main] [message] Log: java.class.path=/usr/share/jedit/jedit.jar
2:37:26 PM [main] [message] jEdit: starting with command line arguments: -log=1
2:37:26 PM [main] [notice] jEdit: An error occurred while connecting to the jEdit server instance.
2:37:26 PM [main] [notice] jEdit: This probably means that jEdit crashed and/or exited abnormally
2:37:26 PM [main] [notice] jEdit: the last time it was run.
2:37:26 PM [main] [notice] jEdit: If you don't know what this means, don't worry.
2:37:26 PM [main] [notice] jEdit: java.lang.IllegalArgumentException: Wrong port file format
2:37:26 PM [main] [notice] jEdit: at org.gjt.sp.jedit.jEdit.main(jEdit.java:310)
2:37:26 PM [main] [debug] jEdit: before splash screen activation:107 ms
2:37:26 PM [main] [debug] jEdit: after splash screen activation:306 ms
2:37:26 PM [main] [debug] MiscUtilities: Saving backup of file "/home/john/.jedit/activity.log" to "/home/john/.jedit/settings-backup/activity.log~1~"
2:37:26 PM [main] [notice] jEdit: jEdit version 5.1.0
2:37:26 PM [main] [message] jEdit: Settings directory is /home/john/.jedit
2:37:26 PM [main] [message] jEdit: jEdit home directory is /usr/share/jedit
2:37:26 PM [main] [debug] SplashScreen: init:39/226ms
2:37:26 PM [main] [debug] SplashScreen: init system properties:58/284ms
2:37:26 PM [main] [message] BeanShell: Beanshell Init
2:37:26 PM [main] [debug] SplashScreen: init beanshell:35/319ms
2:37:26 PM [main] [debug] SplashScreen: loading site properties:6/325ms
2:37:26 PM [main] [debug] SplashScreen: loading user properties:7/332ms
2:37:26 PM [main] [debug] GUIUtilities: Icon theme set to: tango
2:37:26 PM [main] [debug] GUIUtilities: Loading icon theme from: jeditresource:/org/gjt/sp/jedit/icons/themes/tango/
2:37:26 PM [main] [debug] SplashScreen: init GUI:9/341ms
$
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