Installing Java 8 on a Google Compute Debian (Jessie) instance

["James H. H. Lampert" <jamesl@touchtonecorp.com>]

I'm endeavoring to get Java 8 onto our development instance, so that the 
Tomcat environment there matches that of our cluster nodes, and apg-get 
is not cooperating.

This particular instance is a Bitnami SVN/Trac server, with Tomcat 8 
added to it, and running independently of the Apache server that came 
with SVN and Trac.

I tried what was given at
https://stackoverflow.com/q/50919305/3654526
and it didn't work. Even after doing the recommended
> sudo apt-get install dirmngr
> sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys EEA14886
> sudo apt-get update
> sudo apt-get install openjdk-8-jdk -y --allow-unauthenticated

I still get
> Reading package lists... Done
> Building dependency tree
> Reading state information... Done
> Some packages could not be installed. This may mean that you have
> requested an impossible situation or if you are using the unstable
> distribution that some required packages have not yet been created
> or been moved out of Incoming.
> The following information may help to resolve the situation:
>
> The following packages have unmet dependencies:
>  openjdk-8-jdk : Depends: openjdk-8-jre (= 8u171-b11-1~bpo8+1) but it is not going to be installed
>                  Depends: openjdk-8-jdk-headless (= 8u171-b11-1~bpo8+1) but it is not going to be installed
> E: Unable to correct problems, you have held broken packages.

which is what I was getting before.

--
James H. H. Lampert