Java Extending Interfaces
// An interface can extend another interface in the same way that a class can extend another class. The extends keyword is used to extend an interface, and the child interface inherits the methods of the parent interface. Example // Filename: Sports.java public interface Sports { public void setHomeTeam(String name); public void setVisitingTeam(String name); } // Filename: Football.java public interface Football extends Sports { public void homeTeamScored(int points); public void visitingTeamScored(int points); public void endOfQuarter(int quarter); } // Filename: Hockey.java public interface Hockey extends Sports { public void homeGoalScored(); public void visitingGoalScored(); public void endOfPeriod(int period); public void overtimePeriod(int ot); } The Hockey interface has four methods, but it inherits two from Sports. Thus, a class that implements Hockey needs to implement all six methods. Similarly, a class that implements Football needs to define the three methods from Football and the two methods from Sports.