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.
Sitaram, A HashTable (or HashMap in the Collections API) stores data based on a certain value. It calls the hashCode() method to see where the value should be stored. There is also a rule that if you implement hashCode(), you must also implement equals() and vice versa. This is for consistency purposes as objects that are equal must have the same hash code.