java.util.concurrent.SubmissionPublisher#offer ( )源码实例Demo

/**
 * offer returns number of lagged items if not saturated
 */
public void testLaggedOffer() {
    SubmissionPublisher<Integer> p = basicPublisher();
    TestSubscriber s1 = new TestSubscriber();
    s1.request = false;
    TestSubscriber s2 = new TestSubscriber();
    s2.request = false;
    p.subscribe(s1);
    p.subscribe(s2);
    s2.awaitSubscribe();
    s1.awaitSubscribe();
    assertTrue(p.offer(1, null) >= 1);
    assertTrue(p.offer(2, null) >= 2);
    s1.sn.request(4);
    assertTrue(p.offer(3, null) >= 3);
    s2.sn.request(4);
    p.offer(4, null);
    p.close();
    s2.awaitComplete();
    assertEquals(4, s2.nexts);
    s1.awaitComplete();
    assertEquals(4, s2.nexts);
}
 

/**
 * offer reports drops if saturated
 */
public void testDroppedOffer() {
    SubmissionPublisher<Integer> p
        = new SubmissionPublisher<>(basicExecutor, 4);
    TestSubscriber s1 = new TestSubscriber();
    s1.request = false;
    TestSubscriber s2 = new TestSubscriber();
    s2.request = false;
    p.subscribe(s1);
    p.subscribe(s2);
    s2.awaitSubscribe();
    s1.awaitSubscribe();
    for (int i = 1; i <= 4; ++i)
        assertTrue(p.offer(i, null) >= 0);
    p.offer(5, null);
    assertTrue(p.offer(6, null) < 0);
    s1.sn.request(64);
    assertTrue(p.offer(7, null) < 0);
    s2.sn.request(64);
    p.close();
    s2.awaitComplete();
    assertTrue(s2.nexts >= 4);
    s1.awaitComplete();
    assertTrue(s1.nexts >= 4);
}
 

/**
 * offer invokes drop handler if saturated
 */
public void testHandledDroppedOffer() {
    AtomicInteger calls = new AtomicInteger();
    SubmissionPublisher<Integer> p
        = new SubmissionPublisher<>(basicExecutor, 4);
    TestSubscriber s1 = new TestSubscriber();
    s1.request = false;
    TestSubscriber s2 = new TestSubscriber();
    s2.request = false;
    p.subscribe(s1);
    p.subscribe(s2);
    s2.awaitSubscribe();
    s1.awaitSubscribe();
    for (int i = 1; i <= 4; ++i)
        assertTrue(p.offer(i, (s, x) -> noopHandle(calls)) >= 0);
    p.offer(4, (s, x) -> noopHandle(calls));
    assertTrue(p.offer(6, (s, x) -> noopHandle(calls)) < 0);
    s1.sn.request(64);
    assertTrue(p.offer(7, (s, x) -> noopHandle(calls)) < 0);
    s2.sn.request(64);
    p.close();
    s2.awaitComplete();
    s1.awaitComplete();
    assertTrue(calls.get() >= 4);
}
 

/**
 * offer succeeds if drop handler forces request
 */
public void testRecoveredHandledDroppedOffer() {
    AtomicInteger calls = new AtomicInteger();
    SubmissionPublisher<Integer> p
        = new SubmissionPublisher<>(basicExecutor, 4);
    TestSubscriber s1 = new TestSubscriber();
    s1.request = false;
    TestSubscriber s2 = new TestSubscriber();
    s2.request = false;
    p.subscribe(s1);
    p.subscribe(s2);
    s2.awaitSubscribe();
    s1.awaitSubscribe();
    int n = 0;
    for (int i = 1; i <= 8; ++i) {
        int d = p.offer(i, (s, x) -> reqHandle(calls, s));
        n = n + 2 + (d < 0 ? d : 0);
    }
    p.close();
    s2.awaitComplete();
    s1.awaitComplete();
    assertEquals(n, s1.nexts + s2.nexts);
    assertTrue(calls.get() >= 2);
}
 

/**
 * Timed offer returns number of lagged items if not saturated
 */
public void testLaggedTimedOffer() {
    SubmissionPublisher<Integer> p = basicPublisher();
    TestSubscriber s1 = new TestSubscriber();
    s1.request = false;
    TestSubscriber s2 = new TestSubscriber();
    s2.request = false;
    p.subscribe(s1);
    p.subscribe(s2);
    s2.awaitSubscribe();
    s1.awaitSubscribe();
    long startTime = System.nanoTime();
    assertTrue(p.offer(1, LONG_DELAY_MS, MILLISECONDS, null) >= 1);
    assertTrue(p.offer(2, LONG_DELAY_MS, MILLISECONDS, null) >= 2);
    s1.sn.request(4);
    assertTrue(p.offer(3, LONG_DELAY_MS, MILLISECONDS, null) >= 3);
    s2.sn.request(4);
    p.offer(4, LONG_DELAY_MS, MILLISECONDS, null);
    p.close();
    s2.awaitComplete();
    assertEquals(4, s2.nexts);
    s1.awaitComplete();
    assertEquals(4, s2.nexts);
    assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS / 2);
}
 

/**
 * offer(null) throws NPE
 */
public void testNullOffer() {
    SubmissionPublisher<Integer> p = basicPublisher();
    try {
        p.offer(null, null);
        shouldThrow();
    } catch (NullPointerException success) {}
}
 

/**
 * Timed offer succeeds if drop handler forces request
 */
public void testRecoveredHandledDroppedTimedOffer() {
    AtomicInteger calls = new AtomicInteger();
    SubmissionPublisher<Integer> p
        = new SubmissionPublisher<>(basicExecutor, 4);
    TestSubscriber s1 = new TestSubscriber();
    s1.request = false;
    TestSubscriber s2 = new TestSubscriber();
    s2.request = false;
    p.subscribe(s1);
    p.subscribe(s2);
    s2.awaitSubscribe();
    s1.awaitSubscribe();
    int n = 0;
    long delay = timeoutMillis();
    long startTime = System.nanoTime();
    for (int i = 1; i <= 6; ++i) {
        int d = p.offer(i, delay, MILLISECONDS, (s, x) -> reqHandle(calls, s));
        n = n + 2 + (d < 0 ? d : 0);
    }
    assertTrue(millisElapsedSince(startTime) >= delay);
    p.close();
    s2.awaitComplete();
    s1.awaitComplete();
    assertEquals(n, s1.nexts + s2.nexts);
    assertTrue(calls.get() >= 2);
}