How To Revert/Rollback Java?

[JSeymour]

Updated my system, today. Upon reboot I found my Ubiquiti UniFi AP controller software is no longer running:

Code: Select all

Aug 15 13:10:14 jimsun unifi[3454]: ##012# A fatal error has been detected by the Java Runtime Environment:#012##012#  Internal Error (safepoint.cpp:325), pid=4824, tid=139807965468416
Aug 15 13:10:14 jimsun unifi[3454]: #  guarantee(PageArmed == 0) failed: invariant#012##012# JRE version: OpenJDK Runtime Environment (7.0_181-b01) (build 1.7.0_181-b01)#012# Java VM: OpenJDK 64-Bit Server VM (24.181-b01 mixed mode linux-amd64 compressed oops)#012# Derivative: IcedTea 2.6.14#012# Distribution: Ubuntu 14.04 LTS, package 7u181-2.6.14-0ubuntu0.2#012# Failed to write core dump. Core dumps have been disabled. To enable core dumping, try "ulimit -c unlimited" before starting Java again#012#
Aug 15 13:10:14 jimsun unifi[3454]: # An error report file with more information is saved as:#012# //hs_err_pid4824.log

Ubiquiti's "upgraded" their forums, again, and I can't post there. So I guess my only choice is to roll back that JDK upgrade that I installed on the 10th. How do I accomplish that?

Thanks!

(PS: I utterly detest Java.)

[JSeymour]

I guess it's not possible to do it the right way, because it would appear Ubuntu removed the last version. I'll just put the last version back, by hand, from backup.