dummyValue = new Object();
    dummyValueRef = map.newValueReference(dummy, dummyValue, 1);
    dummy.setValueReference(dummyValueRef);
    table.set(index, dummy);
    // returns the most recent entry
    assertSame(dummyValue, segment.get(key, hash));
    assertTrue(segment.containsKey(key, hash));
    assertTrue(segment.containsValue(value));
    assertTrue(segment.containsValue(dummyValue));

    dummyValue = new Object();
    dummyValueRef = map.newValueReference(dummy, dummyValue, 1);
    dummy.setValueReference(dummyValueRef);
    table.set(index, dummy);
    // returns the most recent entry
    assertSame(dummyValue, segment.get(key, hash));
    assertTrue(segment.containsKey(key, hash));
    assertTrue(segment.containsValue(value));
    assertTrue(segment.containsValue(dummyValue));

 *   <li>by combining the results of several input steps.
 * </ul>
 *
 * Each derivation can capture the next value or any intermediate objects for later closing.
 *
 * <p>A step can be the input to at most one derived step. Once you transform its value, catch its
 * exception, or combine it with others, you cannot do anything else with it, including declare it
 * to be the last step of the pipeline.
 *
 * <h4>Transforming</h4>

          K extends @Nullable Object, V extends @Nullable Object>
      extends AbstractMap<K, V> {
    /**
     * Creates the entry set to be returned by {@link #entrySet()}. This method is invoked at most
     * once on a given map, at the time when {@code entrySet} is first called.
     */
    abstract Set<Entry<K, V>> createEntrySet();

    @LazyInit @CheckForNull private transient Set<Entry<K, V>> entrySet;