return oldValue;
    }
  }

  /**
   * If {@code (key, expectedOldValue)} is currently in the map, this method replaces {@code
   * expectedOldValue} with {@code newValue} and returns true; otherwise, this method returns false.
   *
   * <p>If {@code expectedOldValue} is zero, this method will succeed if {@code (key, zero)} is
   * currently in the map, or if {@code key} is not in the map at all.
   */

   * containing one element (the given set itself).
   *
   * <p>Despite the method name, this method attempts to avoid actually copying the data when it is
   * safe to do so. The exact circumstances under which a copy will or will not be performed are
   * undocumented and subject to change.
   *
   * <p>This method is not type-safe, as it may be called on elements that are not mutually
   * comparable.
   *

import com.google.common.annotations.GwtCompatible;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Future;
import java.util.concurrent.TimeoutException;

/** Methods factored out so that they can be emulated differently in GWT. */
@GwtCompatible(emulated = true)
final class TestPlatform {
  static void verifyGetOnPendingFuture(Future<?> future) {
    checkNotNull(future);
    try {

import java.util.concurrent.Executor;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A {@link ListenableFuture} which forwards all its method calls to another future. Subclasses
 * should override one or more methods to modify the behavior of the backing future as desired per
 * the <a href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *

  protected AbstractService() {}

  /**
   * This method is called by {@link #startAsync} to initiate service startup. The invocation of
   * this method should cause a call to {@link #notifyStarted()}, either during this method's run,
   * or after it has returned. If startup fails, the invocation should cause a call to {@link
   * #notifyFailed(Throwable)} instead.
   *

 *       so) before returning from the method. The {@code joinPool} method can be used to do this
 *       when using Executors.
 * </ol>
 *
 * <p><b>Other notes</b>
 *
 * <ul>
 *   <li>Usually, there is one testcase method per JSR166 method covering "normal" operation, and
 *       then as many exception-testing methods as there are exceptions the method can throw.

    private ExecutorService inline = newDirectExecutorService();

    public void assertLastMethodCalled(String method) {
      assertEquals(method, lastMethodCalled);
    }

    public void assertMethodWithTimeout(String method, long timeout, TimeUnit unit) {
      assertLastMethodCalled(method + "Timeout");
      assertEquals(unit.toMillis(timeout), lastTimeoutInMillis);
    }

    @Override

  private final List<PerListenerQueue<L>> listeners =
      Collections.synchronizedList(new ArrayList<PerListenerQueue<L>>());

  /** Method reference-compatible listener event. */
  interface Event<L> {
    /** Call a method on the listener. */
    void call(L listener);
  }

  /**
   * Adds a listener that will be called using the given executor when events are later {@link

import java.util.concurrent.atomic.AtomicLong;

/**
 * One or more variables that together maintain an initially zero {@code long} sum. When updates
 * (method {@link #add}) are contended across threads, the set of variables may grow dynamically to
 * reduce contention. Method {@link #sum} (or, equivalently, {@link #longValue}) returns the current
 * total combined across the variables maintaining the sum.
 *

/**
 * An assortment of mainly legacy static utility methods that operate on or return objects of type
 * {@code Iterable}. Except as noted, each method has a corresponding {@link Iterator}-based method
 * in the {@link Iterators} class.
 *
 * <p><b>Java 8+ users:</b> several common uses for this class are now more comprehensively
 * addressed by the new {@link java.util.stream.Stream} library. Read the method documentation below