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.
I m new to EJB so this may sound naive. I see that the only required tag in persistence.xml is persistence unit with name and all others are optional. My question is, in such a case is persistence.xml file required? Should every project using JPA must have a persistence.xml?