Are the same thing.
You need to specify the module path when you execute a module jar.
-m or
--module
You need to specify the module name when you execute a module jar.
dry-run
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The dry run option loads the main class but does not run it,
used for testing module dependencies are satisfied a successful result is no output
--describe-module
The describe module option gives you summary information about a module including its path, its dependencies, and its packages and resources.