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.
according to sun we can provide implementation for readObject & WriteObject methos in which we can provide some extra information.
so same thing we can do with Externalization using writeExternal & ReadExternal method so what is exact difference between them.