>From now, I solved it when running Arduino IDE. The process is as following: 1. Uninstall the IDE 2. Delete `Arduino/` and `.arduino15/` in `~`. 3. Reinstall. And it never freezes again. I guess maybe it is due to the fact that I changed my java environment without updating the preferences of the app. Taking Arduino IDE as an example, there is preferences.txt in `.arduino15/`. When simply installing a new IDE or uninstalling the original one, the file isn't changed automatically. ```bash $ cat preferences.txt | grep java preproc.imports.list=java.applet.*,java.awt.Dimension,java.awt.Frame,java.awt.event.MouseEvent,java.awt.event.KeyEvent,java.awt.event.FocusEvent,java.awt.Image,java.io.*,java.net.*,java.text.*,java.util.*,java.util.zip.*,java.util.regex.* ```
My current enviroment is Ubuntu 20.04.3 LTS, 5.7.0-050700rc7-generic, java version "17.0.1" 2021-10-19 LTS. So maybe the bug only affects openjdk 8u252. -- You received this bug notification because you are a member of OpenJDK, which is subscribed to openjdk-8 in Ubuntu. https://bugs.launchpad.net/bugs/1880246 Title: Java desktop application freezes with openjdk 8u252 Status in openjdk-8 package in Ubuntu: Confirmed Bug description: When launching the java desktop application Fiji (https://fiji.sc) using the system-wide openjdk 8u252, the UI is frozen. After trying many relaunches, occasionally (1 our of 30 times or so), the application isn't frozen, indicating some sort of race condition. When the UI is frozen, the jconsole indicates that the event dispatch thread is blocked: ``` Name: AWT-EventQueue-1 State: BLOCKED on java.awt.Component$AWTTreeLock@1bde9d17 owned by: main Total blocked: 10 Total waited: 61 Stack trace: java.awt.Container.dispatchEventImpl(Container.java:2300) java.awt.Component.dispatchEvent(Component.java:4711) java.awt.EventQueue.dispatchEventImpl(EventQueue.java:760) java.awt.EventQueue.access$500(EventQueue.java:97) java.awt.EventQueue$3.run(EventQueue.java:709) java.awt.EventQueue$3.run(EventQueue.java:703) java.security.AccessController.doPrivileged(Native Method) java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74) java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:84) java.awt.EventQueue$4.run(EventQueue.java:733) java.awt.EventQueue$4.run(EventQueue.java:731) java.security.AccessController.doPrivileged(Native Method) java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74) java.awt.EventQueue.dispatchEvent(EventQueue.java:730) org.GNOME.Accessibility.AtkWrapper$6.dispatchEvent(AtkWrapper.java:705) java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:205) java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116) java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105) java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101) java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93) java.awt.EventDispatchThread.run(EventDispatchThread.java:82) ``` When launching the Fiji java desktop application with openjdk java 8u172, no such problem occurs ever. ProblemType: Bug DistroRelease: Ubuntu 20.04 Package: openjdk-8-jdk 8u252-b09-1ubuntu1 ProcVersionSignature: Ubuntu 5.4.0-31.35-generic 5.4.34 Uname: Linux 5.4.0-31-generic x86_64 ApportVersion: 2.20.11-0ubuntu27 Architecture: amd64 CasperMD5CheckResult: skip CurrentDesktop: ubuntu:GNOME Date: Fri May 22 22:41:17 2020 EcryptfsInUse: Yes InstallationDate: Installed on 2016-06-24 (1428 days ago) InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1) SourcePackage: openjdk-8 UpgradeStatus: Upgraded to focal on 2020-05-20 (2 days ago) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/openjdk-8/+bug/1880246/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~openjdk Post to : openjdk@lists.launchpad.net Unsubscribe : https://launchpad.net/~openjdk More help : https://help.launchpad.net/ListHelp