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.
No, String is already implementing the Comparable interface, so you don't need anything. In fact, it has nothing to do with equals(). but with Comparable or Comparator. You either implement Comparable, or you provide your own Comparator and pass it as the third parameter of binarySearch.