jessentials-parent
· A parent POM for this library collection, which helps to standardize
the plugins, libraries, and build settings used in the various modules.
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 jessentials-parent-6.0.0.jar file.
Once you open a JAR file, all the java classes in the JAR file will be displayed.