The modules file is a container file. It’s internal to the JDK and the format is not documented (it may change at any time). For troubleshooting purposes, the jimage tool in the bin directory can be used to list or extract the contents.
The purpose of JMODs are not well documented and existing documentation is rather sparse. Here is an in-depth explanation of system, from my understanding. Parts of this answer are rather long, verbose, partially redundant, and a tough read. Constructive, structural, or grammatical edits are more than welcome to improve readability for future readers. Short(er) Answer … Read more