Follow the link in linux with `readlink -e`
Sometimes linux can be a maze of symbolic links. On my system, the java command exists at /usr/bin/java which is a link that points to /etc/alternatives/java which is a link that points to /usr/lib/jvm/java-8-oracle/jre/bin/java.
Instead of looking up each of the links of these files with ls -l, readlink -e will the links all the way through to the eventual file. In my case that would look like this:
$ readlink -e `which java`
# returns /usr/lib/jvm/java-8-oracle/jre/bin/java
You can learn more with man readlink.
On Mac, there is a readlink command, but there is no -e flag and it is not recursive.