Suppose that you are going to create an object used to count the number of people in a room. We know that the number of people in the room can never be negative.

Create a RoomCounter class having three public methods:
• addPerson—adds one person to the room
• removePerson—removes one person from the room
• getCount —returns the number of people in the room
If removePerson would make the number of people less than zero, throw a NegativeCounterException.

See the code in RoomCounter.java.