public class Time implements Comparable {

    // constrants (final) class variables

    static public final int HOURS_PER_DAY      = 24;
    static public final int MINUTES_PER_HOUR   = 60;
    static public final int SECONDS_PER_MINUTE = 60;

    // instance variables

    private int hours;
    private int minutes;
    private int seconds;

    // constructor

    public Time (int hours, int minutes, int seconds) {
        this.hours   = hours;
        this.minutes = minutes;
        this.seconds = seconds;
	normalize ();
    }

    // access instance methods

    public int getHours () {
	return hours;
    }

    public int getMinutes () {
	return minutes;
    }

    public int getSeconds () {
	return seconds;
    }

    // standard instance methods

    public String toString() {
	return getHours ()+":"+getMinutes ()+":"+getSeconds ();
    }

    public boolean equals(Time t) {
	return  (   (hours == t.getHours()) 
		 && (minutes == t.getMinutes()) 
		 && (seconds == t.getSeconds()));
    }

    public boolean before(Time t) {

        return ((getHours () < t.getHours ()) ||
		((getHours () == t.getHours ()) && (getMinutes () < t.getMinutes () )) ||
		((getHours () == t.getHours ()) && (getMinutes () == t.getMinutes ()) &&
		 (getSeconds () < t.getSeconds ())));
    }

    public boolean after(Time t) {
        return ((getHours ()    >  t.getHours ()) ||
		((getHours ()   == t.getHours ()) && 
		 (getMinutes () >  t.getMinutes () )) ||
		((getHours ()   == t.getHours ()) && 
		 (getMinutes () == t.getMinutes ()) &&
		 (getSeconds () >  t.getSeconds ())));
    }
    
    public int compareTo(Comparable obj) {

	Time other;
	other = (Time) obj;

	int result;

	if (before(other)) {
	    result = -1;
	} else if (after(other)) {
	    result = 1;
	} else { // equals
	    result = 0;
	}
	    
	return result;
    }

    // other instance methods

    public void increase() {
	seconds++ ;
	normalize ();
    }

    // private instance method

    private void normalize () {
	int carry = seconds / SECONDS_PER_MINUTE;
	seconds = seconds % SECONDS_PER_MINUTE;
	minutes = minutes + carry ;
	carry = minutes / MINUTES_PER_HOUR;
	minutes = minutes % MINUTES_PER_HOUR;
	hours = (hours + carry) % HOURS_PER_DAY;
    }
}