Apache Maven
· Maven is a software build management and
comprehension tool. Based on the concept of a project object model:
builds, dependency management, documentation creation, site
publication, and distribution publication are all controlled from
the declarative file. Maven can be extended by plugins to utilise a
number of other development tools for reporting or the build
process.
Download JD-GUI to open JAR file and explore Java source code file (.class .java)
Click menu "File → Open File..." or just drag-and-drop the JAR file in the JD-GUI window maven-3.9.4.jar file.
Once you open a JAR file, all the java classes in the JAR file will be displayed.