This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
equals() using to comparison, refers to equivalence relations. hashCode() is id number allocated to an object by JVM. Contract: When you use equals() and hashCode() methods is necessary to override these methods