Summary of jar files

I am a beginner in programming. This time, I got an overview of the jar file, so I will output it.

Q1: What is the jar file made up of?

I felt that it was necessary to know the following three words in order to know it.

① ** Class library **: Convenient functions that can be used in development such as System.out.println and Random (There are many other functions) ② ** Class **: A box for collecting class libraries ③ ** Package **: Box for grouping classes

`Q: Why do I have to package the classes together? ʻA: To distinguish between classes that have the same name in the code.

Summary,,,,,,

Contents of the class Package contents Contents of the jar file
Class library class package

It is like that. A jar file is a compressed package in jar format.

** If you want to know more about jar format, please refer to the URL below ** https://wa3.i-3-i.info/word14171.html

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