Java 9 has introduced a new format called "jmod" to encapsulate modules. The jmod files can be designed to handle more content types than jar files. It can also package local codes, configuration files, local commands, and other types of data. The "jmod" format hasn't support at runtime and can be based on zip format currently. The jmod format can be used at both compile and link time and can be found in JDK_HOME\jmods directory, where JDK_HOME is a directory. The files in jmod format have a ".jmod" extension.
Java 9 comes with a new tool called jmod, and it is located in the JDK_HOME\bin directory. It can be used to create a jmod file, list the contents of a jmod file, print a description of a module, and record the hash value of the module used.
jmod <subcommand> <options> <jmod-file>
The jmod command contains at least one of the following subcommands:
The list and describe subcommands don't accept any options. The <jmod-file> is the jmod file to be created or the existing jmod file to be described.