One quick way to see what classes a jar file contains is to open it in with a tool like WinZip. The filenames shown are the classes. You will need to prepend the package name which you can get by replacing the slashes in the folder names with periods.
For example, jms.jar contains the Java Messaging Service (JMS) classes. If you open this file in WinZip, you will see a file called “ConnectionFactory.class” in a folder named “javax/jms”. The resulting class to import would be “javax.jms.ConnectionFactory”.
You can do something similar from the command line using the command