org.refcodes:refcodes-parent
· Artifact containing information for all refcodes artifacts such as
third party artifacts and their versions being used by refcodes
artifacts as well as the licensing agreements for refcodes artifacts.
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 refcodes-parent-3.2.8.jar file.
Once you open a JAR file, all the java classes in the JAR file will be displayed.