Is the rar file generated by the maven-rar-plugin is the same with the rar file(compressed file) of WinRar?

No. They are entirely different from each other.

A Resource Adapter Archive (RAR) file is a Java archive (JAR) file used to package a resource adapter for the Java 2 Connector (J2C) Architecture

A RAR file can contain the following:

  • Enterprise information system (EIS) supplied resource adapter implementation code in the form of JAR files or other runnable components, such as dynamic link lists.
  • Utility classes.
  • Static documents, such as HTML files, images, and sound files.

While RAR(Roshal ARchive) is the native format of WinRAR archiver. Like other archives, RAR files are data containers, they store one or several files in the compressed form. After you downloaded RAR file from Internet, you need to unpack its contents in order to use it.