package jutil;

/**
 * Used by the Sim framework to represent events in
 * a simulation.
 */
public class Event implements Comparable, java.io.Serializable {
	/**
	 * The time when this event will occur.
	 */
	protected int fireTime;
	/**
	 * Initializes fireTime.
	 */
	public Event(int time) { fireTime = time; }
	/**
	 * Sets fire time to 0.
	 */
	public Event() { this(0); }
	/**
	 * this is less than other if this.fireTime is before
	 * other.fireTime.
	 * @param other  an event to compare with this event.
	 * @return a negative number if this event is before other event,
	 *          a positive number if this event is after other, and
	 *          0 if both occur at the same time.
	 */
	public int compareTo(Object other) {
		if (! (other instanceof Event)) throw new ClassCastException();
		Event e = (Event)other;
		return fireTime - e.fireTime;
	}
	/**
	 * @return firing time
	 */
	public int getFireTime() { return fireTime; }
	/**
	 * Override this method in subclasses.
	 * @return A subsequent event to be scheduled or null.
	 */
	public Event fire() { return null; }
	/**
	 * @return {fireTime}
	 */
	public String toString() {
		return "{" + fireTime + "}";
	}

}