This week's book giveaway is in the Mac OS forum. We're giving away four copies of a choice of "Take Control of Upgrading to Yosemite" or "Take Control of Automating Your Mac" and have Joe Kissell on-line! See this thread for details.
Originally posted by Manoj G S: How to find in which Package a .class file belongs
Have you simply tried it? If you have a .class file (say A.class), and you don't know what package it is in... have you just tried "java -cp . A"? If the A.class file is not in the default package, the class loader should complain about the name being wrong. It will also give you the wrong name -- which includes the package.