73 lines
1.8 KiB
Java
73 lines
1.8 KiB
Java
/**
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* The Event class is an abstract class that encapsulates a
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* discrete event to be simulated. An event encapsulates the
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* time the event occurs. A subclass of event _must_ override
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* the simulate() method to implement the logic of the
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* simulation when this event is simulated. The simulate method
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* returns an array of events, which the simulator will then
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* add to the event queue. Note that an event also implements
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* the Comparable interface so that a PriorityQueue can
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* arrange the events in the order of event time.
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*
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* @author Wei Tsang
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* @version CS2030S AY21/22 Semester 2
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*/
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abstract class Event implements Comparable<Event> {
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/** The time this event occurs in the simulation. */
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private final double time;
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/**
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* Creates an event that occurs at the given time.
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*
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* @param time The time the event occurs.
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*/
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public Event(double time) {
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this.time = time;
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}
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/**
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* Getter to return the time of this event.
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*
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* @return The time this event occurs.
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*/
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public double getTime() {
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return this.time;
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}
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/**
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* Compare this event with a given event e.
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*
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* @param e The other event to compare to.
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* @return 1 if this event occurs later than e;
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* 0 if they occur the same time;
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* -1 if this event occurs earlier.
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*/
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@Override
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public int compareTo(Event e) {
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if (this.time > e.time) {
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return 1;
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} else if (this.time == e.time) {
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return 0;
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} else {
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return -1;
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}
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}
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/**
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* Return the string representation this event.
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*
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* @return A string consists of the time this event occurs.
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*/
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@Override
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public String toString() {
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return String.format("%.3f", this.time);
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}
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/**
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* Simulate this event.
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*
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* @return An array of new events to be scheduled by the simulator.
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*/
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public abstract Event[] simulate();
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}
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