If you need to upgrade your Java version please proceed as follows:
Backup the cacerts file from the location of the existing JDK …/jdk_<old>/jre/lib/security/ or create a new cacerts file including the necessary certificates (e.g. company root certificate).
Install JDK of new Java version on server. Please refer to the system requirements for supported JDK editions.
Copy the cacerts file to the location of the new JDK …/jdk_<new>/jre/lib/security/

• Change JAVA_HOME in <stages>\config.bat according to the location of the new JDK and run <stages>\bin\reinstallservice.bat (as admin).

• Execute the following as root or with sudo
• Create new file that is getting loaded when system is starting/restarting

touch /etc/profile.d/java_home.sh

• Fill the file with variable definition to have an always up to date definition of the JDK in JAVA_HOME and PATH env. variables

cat <<EOF> /etc/profile.d/java_home.sh
export JAVA_HOME=\$(readlink -f /usr/bin/java | sed "s:/bin/java::")
export PATH=\$PATH:\$JAVA_HOME/bin
EOF

• Reload the environment variables with the following command or restart the system

source /etc/profile