* only contain entries which are already present in the cache.
   *
   * @since 11.0
   */
  /*
   * <? extends Object> is mostly the same as <?> to plain Java. But to nullness checkers, they
   * differ: <? extends Object> means "non-null types," while <?> means "all types."
   */
  ImmutableMap<K, V> getAllPresent(Iterable<? extends Object> keys);

  /**

          fail("Expected DecodingException");
        } catch (DecodingException expected) {
          // Don't assert on the expectedMessage; the messages for exceptions thrown from the
          // decoding stream may differ from the messages for the decode methods.
        } catch (IOException e) {
          fail("Expected DecodingException but got: " + e);
        }
      }
    },
    CAN_DECODE {
      @Override

    /*
     * These gymnastics are a little confusing. Basically this class has neither legacy nor
     * non-legacy behavior; it just needs to let the behaviors of the backing converters shine
     * through (which might even differ from each other!). So, we override the correctedDo* methods,
     * after which the do* methods should never be reached.
     */

    @Override
    protected C doForward(A a) {
      throw new AssertionError();

 *       then as many exception-testing methods as there are exceptions the method can throw.
 *       Sometimes there are multiple tests per JSR166 method when the different "normal" behaviors
 *       differ significantly. And sometimes testcases cover multiple methods when they cannot be
 *       tested in isolation.
 *   <li>The documentation style for testcases is to provide as javadoc a simple sentence or two

   * hash functions. This is critical when the concurrent hash map uses power-of-two length hash
   * tables, that otherwise encounter collisions for hash codes that do not differ in lower or upper
   * bits.
   *
   * @param h hash code
   */
  static int rehash(int h) {
    // Spread bits to regularize both segment and index locations,

    Future<?> localTimer = timer;
    // Try to cancel the timer as an optimization.
    // timer may be null if this call to run was by the timer task since there is no happens-before
    // edge between the assignment to timer and an execution of the timer task.
    if (localTimer != null) {
      localTimer.cancel(false);
    }

    delegateRef = null;
    timer = null;
  }

  }

  // Node sets are the same, but edge sets differ.
  @Test
  public void equivalent_edgeSetsDiffer() {
    network.addEdge(N1, N2, E12);

    MutableNetwork<Integer, String> g2 = createNetwork(edgeType);
    g2.addEdge(N1, N2, E13);

    assertThat(network).isNotEqualTo(g2);
  }

  // Node/edge sets are the same, but node/edge connections differ due to edge type.
  @Test

    graph.addNode(N1);

    MutableGraph<Integer> g2 = createGraph(edgeType);
    g2.addNode(N2);

    assertThat(graph).isNotEqualTo(g2);
  }

  // Node/edge sets are the same, but node/edge connections differ due to edge type.
  @Test
  public void equivalent_directedVsUndirected() {
    graph.putEdge(N1, N2);

    MutableGraph<Integer> g2 = createGraph(oppositeType(edgeType));
    g2.putEdge(N1, N2);

      producer.beganProducing.await();

      // make sure we time out
      Stopwatch timer = Stopwatch.createStarted();

      int drained = drain(q, newArrayList(), 2, 10, MILLISECONDS, interruptibly);
      assertThat(drained).isAtMost(1);

      assertThat(timer.elapsed(MILLISECONDS)).isAtLeast(10L);

    assertThat(startupTimes).hasSize(2);
    assertThat(startupTimes.get(a)).isAtLeast(150);
    // Service b startup takes at least 353 millis, but starting the timer is delayed by at least
    // 150 milliseconds. so in a perfect world the timing would be 353-150=203ms, but since either
    // of our sleep calls can be arbitrarily delayed we should just assert that there is a time