The basic format of the command for creating a JAR file is:
jar cf jar-file input-file(s)
The options and arguments used in this command are:
The c option indicates that you want to create a JAR file.
The f option indicates that you want the output to go to a file rather than to stdout.
jar-file is the name that you want the resulting JAR file to have. You
can use any filename for a JAR file. By convention, JAR filenames are
given a .jar extension, though this is not required.
The input-file(s) argument is a space-separated list of one or more
files that you want to include in your JAR file. The input-file(s)
argument can contain the wildcard * symbol. If any of the
"input-files" are directories, the contents of those directories are
added to the JAR archive recursively.
# 1 楼答案
你可以用罐子包装任何东西。jar基本上只是一个zip文件。从Oracle Documentation