Karaf unable to install jena - jena

Question

I'm trying to install jena (as a requirement of Islandora), running Karaf 4.2.11, however when I run the command to install, /opt/karaf/bin/client feature:install jena, an error is returned. I got the full text of the error, located below, from the Karaf log.
2021-09-14T11:10:00,610 | ERROR | Thread-57 | ShellUtil | 38 - org.apache.karaf.shell.core - 4.2.11 | Exception caught while executing command
org.apache.felix.resolver.reason.ReasonException: Unable to resolve root: missing requirement [root] osgi.identity; osgi.identity=jena; type=karaf.feature; version="[4.1.0,4.1.0]"; filter:="(&(osgi.identity=jena)(type=karaf.feature)(version>=4.1.0)(version<=4.1.0))" [caused by: Unable to resolve jena/4.1.0: missing requirement [jena/4.1.0] osgi.identity; osgi.identity=org.apache.jena.osgi; type=osgi.bundle; version="[4.1.0,4.1.0]"; resolution:=mandatory [caused by: Unable to resolve org.apache.jena.osgi/4.1.0: missing requirement [org.apache.jena.osgi/4.1.0] osgi.ee; filter:="(&(osgi.ee=JavaSE)(version=11))"]]
at org.apache.felix.resolver.Candidates$MissingRequirementError.toException(Candidates.java:1343) ~[?:?]
at org.apache.felix.resolver.ResolverImpl.doResolve(ResolverImpl.java:392) ~[?:?]
at org.apache.felix.resolver.ResolverImpl.resolve(ResolverImpl.java:378) ~[?:?]
at org.apache.felix.resolver.ResolverImpl.resolve(ResolverImpl.java:332) ~[?:?]
at org.apache.karaf.features.internal.region.SubsystemResolver.resolve(SubsystemResolver.java:257) ~[?:?]
at org.apache.karaf.features.internal.service.Deployer.deploy(Deployer.java:401) ~[?:?]
at org.apache.karaf.features.internal.service.FeaturesServiceImpl.doProvision(FeaturesServiceImpl.java:1063) ~[?:?]
at org.apache.karaf.features.internal.service.FeaturesServiceImpl.lambda$doProvisionInThread$13(FeaturesServiceImpl.java:998) ~[?:?]
at java.util.concurrent.FutureTask.run(FutureTask.java:266) ~[?:1.8.0_292]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) ~[?:1.8.0_292]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) ~[?:1.8.0_292]
at java.lang.Thread.run(Thread.java:748) [?:1.8.0_292]
Caused by: org.apache.felix.resolver.reason.ReasonException: Unable to resolve jena/4.1.0: missing requirement [jena/4.1.0] osgi.identity; osgi.identity=org.apache.jena.osgi; type=osgi.bundle; version="[4.1.0,4.1.0]"; resolution:=mandatory [caused by: Unable to resolve org.apache.jena.osgi/4.1.0: missing requirement [org.apache.jena.osgi/4.1.0] osgi.ee; filter:="(&(osgi.ee=JavaSE)(version=11))"]
at org.apache.felix.resolver.Candidates$MissingRequirementError.toException(Candidates.java:1343) ~[?:?]
... 12 more
Caused by: org.apache.felix.resolver.reason.ReasonException: Unable to resolve org.apache.jena.osgi/4.1.0: missing requirement [org.apache.jena.osgi/4.1.0] osgi.ee; filter:="(&(osgi.ee=JavaSE)(version=11))"
at org.apache.felix.resolver.Candidates$MissingRequirementError.toException(Candidates.java:1343) ~[?:?]
at org.apache.felix.resolver.Candidates$MissingRequirementError.toException(Candidates.java:1343) ~[?:?]
... 12 more
I've not used Karaf before, but I've looked through a lot of issues and can't seem to decipher the error, though I think it has to do with the Java version? I'm running version 11.0.11 of openJDK. It seems to me like that's the version it's asking for, though. Is there some configuration I'm missing?
I'm happy to supply any other troubleshooting info, I just can't find where to go from here, not having worked with Karaf before.

Answer 1

The issue here is that Karaf is being run with Java 8. You can see evidence of that in the line:
at java.lang.Thread.run(Thread.java:748) [?:1.8.0_292]
(The execution environment is Java 1.8.0_292)
Jena 4.x requires Java 11+
In order to use Java 11, be sure to set the JAVA_HOME environment value to point to the correct installation. On linux-based environments, this can often be handled with the update-alternatives --config java command