//An instance of this class represents a set of Objects
// that implement the Measurable interface:
//                    double getMeasure()
//
//A DataSet instance provides the following functionality:
//
// DataSet() - default constructor creates an empty DataSet
// void add(Measurable obj) - add a Measurable to this DataSet
// int getNumber() - the # of Measurables in this DataSet
// double getAverage() - the average of the Measurables this DataSet
// Measurable getMaximum() - the largest Measurable of this DataSet
//
//This implementation is a variation of an example from p466 of
// the the textbook, Big Java - Cay Horstman - 5th ed.
// based on implementation of earlier editions
//
public class DataSet
{
	//Instance Variables
	private int number;		//Number of Measurables in this DataSet
	private double total;	//Total of all Measurables (balances) in this DataSet
	private Measurable maximum;	//Largest Measurable in this DataSet
	
	//Default Constructor
	public DataSet()
	{
		this.number = 0;
		this.total = 0.0;
		this.maximum = null;
	}
	
	//Accessor
	public int getNumber()
	{
		return this.number;
	}
	
	//Accessor
	public double getAverage()
	{
		if (this.number == 0)
			return 0.0;
		else
			return this.total / this.number;
	}
	
	//Accessor
	public Measurable getMaximum()
	{
		return this.maximum;
	}
	
	//Mutator: Add another item to the Data Set
	public void add(Measurable item)
	{
		this.number++;
		this.total += item.getMeasure();
		
		if (this.number == 1 || item.getMeasure() > this.maximum.getMeasure())
			this.maximum = item;
	}
}