When following the RedHat documentationfor installing Oracle JDK 8 it is being installed in a location that does not seem to be detected by the bigtop-detect-javahome script.
It is being installed in a directory that looks like this: /usr/lib/jvm/java-1.8.0-oracle-18.104.22.168-1jpp.1.el7_3.x86_64
From the RPM postinstall script:
I would suggest adding those three locations. The last two can be added to JAVA8_HOME_CANDIDATES and the first to MISCJAVA_HOME_CANDIDATES.
If you agree I'm happy to prepare a patch.