CIS 260 HorseRace.java

Code

public class HorseRace {
    public static void main( String args[] ) {
        Horse[] horse = new Horse[4];
        for (int i=0; i<horse.length; i++) {
            horse[i] = new Horse(i+1);
        }
        System.err.println( "\nStarting race" );
        Horse.resetRace();
        for (int i=0; i<horse.length; i++) horse[i].start();
        Reporter rpt = new Reporter(horse);
        rpt.start();
    }
}

class Reporter extends Thread {
    Horse[] horse;
    public Reporter(Horse[] h) {
        System.out.println("And they're off...");
        horse = h;
    }

    public void run() {
        System.out.print("Horse     ");
        for (int i=0; i<horse.length; i++) {
            System.out.printf("%6d ", (i+1));
        }
        System.out.println();
        while (!Horse.done()) {
            System.out.print("\r");
            System.out.print("Distance  ");
            for (int i=0; i<horse.length; i++) {
                System.out.printf("%6d ", horse[i].getDistance());
            }
        }
        System.out.print("\r");
        System.out.print("Distance  ");
        for (int i=0; i<horse.length; i++) {
            System.out.printf("%6d ", horse[i].getDistance());
        }
        System.out.println("\nAnd the winner is "
            + Horse.getWinner());
    }
}

class Horse extends Thread {
    private static boolean raceOver = false;
    private static final int raceLength = 1000;
    private static String winner = "";
    private int distance;
    private String name = "";

    public Horse(int id) {
        name = "Horsie #" + id;
        distance = 0;
    }

    public static void resetRace() { raceOver = false; }
    public static boolean done() { return raceOver; }
    public static String getWinner() { return winner; }
    public int getDistance() { return distance; }

    public void run() {
        while (!raceOver) {
            try {
                // get a little rest and then move
                Thread.sleep((int)(Math.random() * 500));
                if (++distance >= raceLength) raceOver = true;
            } catch (InterruptedException e) {
                System.err.println(e);
            }
        }
        if (distance == raceLength) winner = name;
    }
}