At this point, I'm basically just grasping at straws, as I've reached the limit of my Linux knowledge. How can I get these environment variables to be visible to every process on boot?

Jack Wallen shows you how to pass environment variables to Docker containers for a more efficient development process.

JAVA_HOME is an operating system (OS) environment variable which can optionally be set after either the Java Development Kit (JDK) or the Java Runtime Environment (JRE) is installed. The JAVA_HOME ...