Race.java

public class Race {
	private static boolean raceFinished = false;
	private static String winner;

	public static void main(String[] args) throws InterruptedException {

		Thread[] players = new Thread[10];

		// Fill the array
		for (int i = 0; i < players.length; i++) {
			players[i] = makeNewPlayer(i);
			players[i].setName("Player " + (i + 1));
			System.out.println(players[i].getName() +" added");
		}

		System.out.println("\nBegin race\n");
		long startTime = System.currentTimeMillis();

		// Start each Thread
		for (Thread player : players) {
			player.start();
			System.out.println(player.getName() +" started");
		}

		// makes the main thread wait for the player
		for (Thread player : players) {
			player.join();
		}

		// Duration.between(startTime, Instant.now()) -> calculates the duration of race
		long endTime = System.currentTimeMillis();
		long duration = endTime - startTime;
		System.out.println("\nThe race is finished. Duration : " + duration +" ms");
		System.out.println("The winner is : " + winner);

	}

	private static Thread makeNewPlayer(int index) {
		// Returns a new thread which it's run method loops for 100 time units
		// (100 m)
		return new Thread(new Runnable() {
			@Override
			public void run() {
				for (int j = 0; j < 100; j++) {
					try {
						Thread.sleep(10);
					} catch (InterruptedException e) {
						e.printStackTrace();
					}
				}
				// Now let the thread finish the race
				// This method is called for each thread
				finishRace(Thread.currentThread().getName());
			}
		});
	}

	// This method must be synchronized
	private static synchronized void finishRace(String name) {

		// Change a simple flag condition to prevent others from accessing it after
		// it has been accessed the first time
		// The first thread will make raceFinished true and others threads when they
		// call this method won't be able to declare themselves as winners :D
		if (!raceFinished) {
			raceFinished = true;
			winner = name;
		}
	}
}