This week's giveaway is in the EJB and other Java EE Technologies forum. We're giving away four copies of EJB 3 in Action and have Debu Panda, Reza Rahman, Ryan Cuprak, and Michael Remijan on-line! See this thread for details.
In Andrew's book there's usage of writeLock().lock() for persist method. Here in my case I think its not required. dataSectionOffset is always same(It is set in the beginning only once when the server starts). dbInfo instance stores this kind of data, like dataSectionOffset and recordLength. synchronization of dbFile (RandomAccessFile) I guess is enough for this function. Let me know if I am wrong..!!???