@"Jeff Smith Sqldev Pm-Oracle"
Jeff,
I'm finding quite a few forum threads regarding SQL Developer 4 hanging or crashing and I may have a possible solution for you. It's specifically related to Gnome 3 based Linux desktop environments, which would include Gnome 3, Cinnamon, Unity and possibly others that I'm not aware of. These desktop environments are used by the biggest/most popular Linux distributions. That would include Linux Mint (Ubuntu/Debian based), Ubuntu and Fedora. That's a huge audience of developers and it's getting bigger all the time as Java and database developers look to better development environments such as Linux. Windows has become such a burden to develop on due to all the security issues and the resulting malware software bloat that cripples it, making it extremely frustrating for most developers.
The solution is to implement Gnome's development guidelines as described here: https://wiki.gnome.org/Projects/GnomeShell/ApplicationBased
I think you'll find that setting the WM_CLASS is the most important part of the solution as the other items described do not fully correct the problem.
The problem appears to be that the desktop/window manager in these Linux desktop environments rely heavily on the WM_CLASS. If it is not set and is not unique, when the desktop/window manager checks the status, location, etc. of each application, due to a user event such as a mouse click or a window activation, or even a system event like a screensaver turning on, it throws an error when trying to load the WM_CLASS for SQL Developer. When this error occurs SQL Developer appears to stop responding to user events such as mouse clicks, window activation, moves, etc. I believe what happens is that the desktop/window manager basically looses track of the SQL Developer application so it can no longer communicate with it. This causes the appearance of being hung and may also cause it to crash depending on circumstances. I'm pretty sure the desktop/window manager for all of these desktops is currently MDM.
I've attached an image of my desktop debugger window showing the Oracle SQL Developer application/window with a blank WMClass and an Application status of <untracked>.
Hopefully this information will help your developers stabilize SQL Developer for these extremely popular Linux environments.
Let me know if you have any questions.
Thanks for your time reviewing this.
Roger
Linux Mint 17.3 LTS with Cinnamon DE