Openfire Plugin Assembly Descriptor
· A shared assembly descriptor for Openfire plugins. See
http://maven.apache.org/plugins/maven-assembly-plugin/examples/sharing-descriptors.html
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 openfire-plugin-assembly-descriptor-4.2.0.jar file.
Once you open a JAR file, all the java classes in the JAR file will be displayed.