Java Authentication and Authorization Service
· The Java Authentication and Authorization Service (JAAS) is a set of APIs that enable services to authenticate and enforce access controls upon users.
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 jaas-1.0.01.jar file.
Once you open a JAR file, all the java classes in the JAR file will be displayed.