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.
Read from the JarInputStream directly. Everytime you call getNextJarEntry it positions itself to the next entry, and you can read its contents until all is read (read returns -1). Then you call getNextJarEntry again and read all again.