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.
In general, Yes. Just as you would place class files in a jar; by using the jar tool. jar command doesnt differentiate between class files or any other files, all files in the target directory are included in the generated jar.