/** A repository of historical data which provides various kinds of statistics
 * on the data.
 * @author <your name here>
 */
public class HistoricalData {

    // add some private fields to this class

    /** Initialize this HistoricalData object so that
     * it has no accumulated data.
     */
    public HistoricalData() {
        // replace, if necessary, this comment with code, or delete it
    }

    /** Add a measurement to the accumulated data. 
     * @param measurement The value of this measurement.
     */
    public void add(double measurement) {
        return; // replace this line
    }

    /** Add each measurement in measurements to the accumulated data. 
     * @param measurements The measurements to be added.
     */
    public void addAll(double[] measurements) {
        return; // replace this line
    }

    /** Return the number of measurements stored in this
     * object's accumulated data.
     * @return int The number of elements stored.
     */
    public int size() {
        return 0; // replace this line
    }

    /** Return the average of the accumulated data. 
     * @return double The sum of the accumulated measurements divided by
     * the number of measurements.
     * @throws IllegalStateException When there are no measurements.
     */
    public double average() throws IllegalStateException {
        return 0.0; // replace this line
    }
    
    /** Return the maximum value seen in the accumulated data. 
     * @return double The maximum of the accumulated measurements.
     * @throws IllegalStateException When there are no measurements.
     */
    public double max() throws IllegalStateException {
        return 0.0; // replace this line
    }
    
    /** Return a string representation of this object.
     * @see java.lang.Object#toString()
     */
    public String toString() {
    	int mySize = size();
    	return super.getClass().getName().toString()
    		+ "[" 
    		+ mySize
    		+ ": " + (mySize > 0 ? Double.toString(average()) : "-")
    		+ "]";
    }
    
    /** Return true if the argument is a HistoricalData object
     * with the same size, maximum, and average.
     * @see java.lang.Object#equals(Object)
     */
    public boolean equals(Object oth) {
    	return false; // replace this line
    }
    
    
    /** Return a hash code for this object.
     * @see java.lang.Object#hashCode()
     */
    public int hashCode() {
    	return 0; // replace this line
    }
    
    /** Return a clone of this object.
     * @see java.lang.Object#clone()
     */
    public Object clone() {
    	return null; // replace this line
    } 

    // you can add any needed private methods here, or delete this comment
}