This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
You can't really do a whole lot to protect your JAR files and class files from being decompiled. About the only thing to do is Obfuscate the bytecode so even if it is decompiled, it won't make much sense. I linked to the first one I ran across on google. There are many many more choices out there for obfuscating bytecode. [ January 24, 2005: Message edited by: Gregg Bolinger ]