I asked about this on the SQuirreL mailing list, but I'm having trouble getting a response.
I often use SQuirreL to browse Oracle dbs. If the coection times out, I just use the "Recoect" menu item, and it reopens the coection perfectly fine.
I'm now working with some MariaDB databases. When I attempt to recoect, I just get a "Coection is close" error in SQuirreL. I find that if I completely close the pane and start a new coection to the alias, it successfully coects.
I know that in my Tomcat instance that coects to this db, I have to set some flags to "test" the coection at certain points, to flush coections that get into a bad state. I imagine my fix would be to configure the coection in SQuirreL to do something similar, but I don't see an obvious way to do this in SQuirreL. I can see that there are some property settings that I can set, but it's not really clear exactly how I should be doing this.