import java.time.Duration;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicLong;

/**
 * A Ticker whose value can be advanced programmatically in test.
 *
 * <p>The ticker can be configured so that the time is incremented whenever {@link #read} is called:
 * see {@link #setAutoIncrementStep}.
 *
 * <p>This class is thread-safe.
 *
 * @author Jige Yu
 * @since 10.0
 */

 * a regular priority queue, the methods {@link #peekLast}, {@link #pollLast} and {@link
 * #removeLast} are also provided, to act on the <i>greatest</i> element in the queue instead.
 *
 * <p>A min-max priority queue can be configured with a maximum size. If so, each time the size of
 * the queue exceeds that value, the queue automatically removes its greatest element according to

   *       {@link Futures#addCallback} throws an exception, that exception will be typically be
   *       logged by the {@link ListenableFuture} implementation, even if the thread is configured
   *       to do something different. In other cases, no code will catch the exception, and it may
   *       terminate whichever thread happens to trigger the execution.
   * </ul>
   *