* href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p>Note that {@link #get}, {@link #getUnchecked}, and {@link #apply} all expose the same
 * underlying functionality, so should probably be overridden as a group.
 *
 * @author Charles Fry
 * @since 11.0
 */
@GwtIncompatible
@ElementTypesAreNonnullByDefault

      super(new Object(), frq);
    }

    @Override
    public void finalizeReferent() {
      finalizeReferentCalled = true;
    }
  }

  /**
   * Keeps a weak reference to the underlying reference queue. When this reference is cleared, we
   * know that the background thread has stopped and released its strong reference.
   */
  private WeakReference<ReferenceQueue<Object>> queueReference;

      super(new Object(), frq);
    }

    @Override
    public void finalizeReferent() {
      finalizeReferentCalled = true;
    }
  }

  /**
   * Keeps a weak reference to the underlying reference queue. When this reference is cleared, we
   * know that the background thread has stopped and released its strong reference.
   */
  private WeakReference<ReferenceQueue<Object>> queueReference;

    private static final long serialVersionUID = 0L;
  }

  static void checkMemoize(CountingSupplier countingSupplier, Supplier<Integer> memoizedSupplier) {
    // the underlying supplier hasn't executed yet
    assertEquals(0, countingSupplier.calls);

    assertEquals(10, (int) memoizedSupplier.get());

    // now it has
    assertEquals(1, countingSupplier.calls);

    private static final long serialVersionUID = 0L;
  }

  static void checkMemoize(CountingSupplier countingSupplier, Supplier<Integer> memoizedSupplier) {
    // the underlying supplier hasn't executed yet
    assertEquals(0, countingSupplier.calls);

    assertEquals(10, (int) memoizedSupplier.get());

    // now it has
    assertEquals(1, countingSupplier.calls);

   * called on the filtered collection, only elements that satisfy the filter will be removed from
   * the underlying collection.
   *
   * <p>The returned collection isn't threadsafe or serializable, even if {@code unfiltered} is.
   *
   * <p>Many of the filtered collection's methods, such as {@code size()}, iterate across every
   * element in the underlying collection and determine which elements satisfy the filter. When a

   * that satisfy the filter will be removed from the underlying set.
   *
   * <p>The returned set isn't threadsafe or serializable, even if {@code unfiltered} is.
   *
   * <p>Many of the filtered set's methods, such as {@code size()}, iterate across every element in
   * the underlying set and determine which elements satisfy the filter. When a live view is

        throw error;
      }
    }
    return urls.build();
  }

  /**
   * These tests fail in JDK 9 and JDK 10 for an unknown reason. It might be the test; it might be
   * the underlying functionality. Fixing this is not a high priority; if you need it to be fixed,
   * please comment on <a href="https://github.com/google/guava/issues/3086">issue 3086</a>.
   */
  private static boolean isJdk9OrHigher() {

    underlying.remove("c");
    assertEquals(underlying.size(), map.size());
    assertFalse(map.containsKey("c"));

    underlying.clear();
    assertEquals(underlying.size(), map.size());
  }

  public void testTransformChangesAreReflectedInUnderlyingMap() {
    Map<String, Integer> underlying = Maps.newLinkedHashMap();
    underlying.put("a", 1);
    underlying.put("b", 2);
    underlying.put("c", 3);

     *
     * @return the element corresponding to this entry
     */
    @ParametricNullness
    E getElement();

    /**
     * Returns the count of the associated element in the underlying multiset. This count may either
     * be an unchanging snapshot of the count at the time the entry was retrieved, or a live view of
     * the current count of the element in the multiset, depending on the implementation. Note that