[Ch15] Finally have an example which is really losing updates (83b6b00e) · Commits · examples / Head First Java 3rd Edition

src/main/java/ch15/TestSyncTest.java

+9 −13

Changes for src/main/java/ch15/TestSyncTest.java: 9 added lines, 13 removed lines.
Original line number	Diff line number	Diff line
		@@ -6,19 +6,20 @@ import java.util.concurrent.TimeUnit;

		public class TestSyncTest {
		public static void main(String[] args) throws InterruptedException {
		ExecutorService pool = Executors.newFixedThreadPool(2);
		ExecutorService pool = Executors.newFixedThreadPool(6);
		Balance balance = new Balance();
		pool.execute(() -> incrementBalance50Times(balance));
		pool.execute(() -> incrementBalance50Times(balance));
		for (int i = 0; i < 1000; i++) {
		pool.execute(() -> incrementBalance(balance));
		}
		pool.shutdown();
		pool.awaitTermination(10, TimeUnit.SECONDS);
		// make sure the pool has finished running all the updates before printing the output
		if (pool.awaitTermination(1, TimeUnit.MINUTES)) {
		System.out.println("balance.balance = " + balance.balance);
		}
		}

		private static void incrementBalance50Times(Balance balance) {
		for (int i = 0; i < 50; i++) {
		private static void incrementBalance(Balance balance) {
		balance.increment();
		System.out.printf("Balance updated by %s. Balance is %d%n", Thread.currentThread().getName(), balance.balance);
		}
		}
		}

		@@ -27,11 +28,6 @@ class Balance {

		public void increment() {
		int i = balance;
		try {
		Thread.sleep(1);
		} catch (InterruptedException e) {
		e.printStackTrace();
		}
		balance = i + 1;
		}
		}