*/
@NullMarked
@GwtCompatible
public class SuppliersTest extends TestCase {

  static class CountingSupplier implements Supplier<Integer> {
    int calls = 0;

    @Override
    public Integer get() {
      calls++;
      return calls * 10;
    }

    @Override
    public String toString() {
      return "CountingSupplier";
    }
  }

        NtlmHttpServletRequest request = new NtlmHttpServletRequest(mockRequest, mockPrincipal);
        assertEquals("NTLM", request.getAuthType());
        // Verify it returns the same value on multiple calls
        assertEquals("NTLM", request.getAuthType());
    }

The process that happens when your API app calls the *external API* is named a "callback". Because the software that the external developer wrote sends a request to your API and then your API *calls back*, sending a request to an *external API* (that was probably created by the same developer).

            }
        };

        // Test multiple calls
        Map<String, Object> params = new HashMap<>();
        params.put("test", "value");

        assertNull(queryRescorer.evaluate(params)); // First call - odd
        assertNotNull(queryRescorer.evaluate(params)); // Second call - even
        assertNull(queryRescorer.evaluate(params)); // Third call - odd

    // unless it's actually going to be used; validate() is called for all set method calls, so it
    // needs to be fast.
    // (We could instead generate the message once, when the set is created, but zero is better.)
    if (!validator.get()) {
      throw new IllegalStateException(errorMessage.get());
    }
  }

     */
    List<FileNotifyInformation> watch() throws CIFSException;

    /**
     * {@inheritDoc}
     *
     * @see java.util.concurrent.Callable#call()
     */
    @Override
    List<FileNotifyInformation> call() throws CIFSException;

    /**
     * {@inheritDoc}
     *
     * @see java.lang.AutoCloseable#close()
     */
    @Override
    void close() throws CIFSException;

    // TODO: test whether null is supported (create a Feature)
    /**
     * The elements to be returned by future calls to {@code next()}, with the first at the top of
     * the stack.
     */
    final Stack<E> nextElements = new Stack<>();

    /**
     * The elements to be returned by future calls to {@code previous()}, with the first at the top
     * of the stack.
     */

  /**
   * Precondition tester for {@code Iterator.remove()} that throws an exception with a consistent
   * error message.
   */
  static void checkRemove(boolean canRemove) {
    checkState(canRemove, "no calls to next() since the last call to remove()");
  }

  private CollectPreconditions() {}

 * using a lock, however it is dangerous to dispatch listeners while holding a lock because they
 * might run on the {@code directExecutor()} or be otherwise re-entrant (call back into your
 * object). So it is important to not call {@link #dispatch} while holding any locks. This is why
 * {@link #enqueue} and {@link #dispatch} are 2 different methods. It is expected that the decision

      // racing addListener calls and addListener calls completing after the future completes.
      Runnable listener = k % 2 == 0 ? collectResultsRunnable : collectResultsTimedGetRunnable;
      allTasks.add(callable(listener));
      allTasks.add(
          new Callable<@Nullable Void>() {
            @Override
            public @Nullable Void call() throws Exception {