@SuppressWarnings("unchecked")
  public void ignore_testSerializationNoDuplication_regularImmutableMap() throws Exception {
    // Tests that serializing a map, its keySet, and values only writes the underlying data once.

    Entry<Integer, Integer>[] entries = (Entry<Integer, Integer>[]) new Entry<?, ?>[1000];
    for (int i = 0; i < 1000; i++) {
      entries[i] = ImmutableMap.entryOf(i, i);
    }

   * {@code sequence} as a sequence of Unicode code units. The view does not support any
   * modification operations, but reflects any changes to the underlying character sequence.
   *
   * @param sequence the character sequence to view as a {@code List} of characters
   * @return an {@code List<Character>} view of the character sequence
   * @since 7.0
   */

    @Override
    public V next() {
      return nextEntry().getValue();
    }
  }

  /**
   * Custom Entry class used by EntryIterator.next(), that relays setValue changes to the underlying
   * map.
   */
  final class WriteThroughEntry implements Entry<K, V> {
    final K key; // non-null
    V value; // non-null

    WriteThroughEntry(K key, V value) {
      this.key = key;

    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);

   * the source will contain the concatenated data from the streams of the underlying sources.
   *
   * <p>Only one underlying stream will be open at a time. Closing the concatenated stream will
   * close the open underlying stream.
   *
   * @param sources the sources to concatenate
   * @return a {@code CharSource} containing the concatenated data
   * @since 15.0

   * the source will contain the concatenated data from the streams of the underlying sources.
   *
   * <p>Only one underlying stream will be open at a time. Closing the concatenated stream will
   * close the open underlying stream.
   *
   * @param sources the sources to concatenate
   * @return a {@code ByteSource} containing the concatenated data
   * @since 15.0

   *
   * <p>A collection is considered immutable if:
   *
   * <ol>
   *   <li>All its mutation methods result in UnsupportedOperationException, and do not change the
   *       underlying contents.
   *   <li>All methods that return objects that can indirectly mutate the collection throw
   *       UnsupportedOperationException when those mutators are called.
   * </ol>
   *

import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * An abstract {@code ScheduledExecutorService} that allows subclasses to {@linkplain
 * #wrapTask(Callable) wrap} tasks before they are submitted to the underlying executor.
 *
 * <p>Note that task wrapping may occur even if the task is never executed.
 *
 * @author Luke Sandberg
 */
@J2ktIncompatible
@GwtIncompatible
@ElementTypesAreNonnullByDefault

 * 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;