This sub-package of commons is distributed as standalone JAR file which can easily be integrated into other JAR files. If the main class JarInfo is set as main class within the MANIFEST.MF file, the functionality can be utilized. If a library JAR file is executed standalone normally the user gets a simple error dialog telling that the main class attribute could not be found. To give the user more information about what to do with the library file, the info sub-package can be used. On headless Java environment (only command line interface CLI) the name and path of the JAR file, a short message, and the manifest contents is displayed. In JVM's with graphical displays a dialog shows up, which displays the manifest file of the JAR as well as the list of files and directories included in the archive.