*
   * @throws NullPointerException if any key or value in {@code multimap} is null
   */
  public static <K, V> ImmutableListMultimap<K, V> copyOf(
      Multimap<? extends K, ? extends V> multimap) {
    if (multimap.isEmpty()) {
      return of();
    }

    // TODO(lowasser): copy ImmutableSetMultimap by using asList() on the sets
    if (multimap instanceof ImmutableListMultimap) {

  }

  public void testFilterFiltered() {
    Multimap<String, Integer> unfiltered = HashMultimap.create();
    unfiltered.put("foo", 55556);
    unfiltered.put("badkey", 1);
    unfiltered.put("foo", 1);
    Multimap<String, Integer> keyFiltered = Multimaps.filterKeys(unfiltered, KEY_PREDICATE);
    Multimap<String, Integer> filtered = Multimaps.filterValues(keyFiltered, VALUE_PREDICATE);
    assertEquals(1, filtered.size());

 * "https://github.com/google/guava/wiki/NewCollectionTypesExplained#multimap">{@code Multimap}</a>.
 *
 * @author Jared Levy
 * @since 2.0
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public interface ListMultimap<K extends @Nullable Object, V extends @Nullable Object>
    extends Multimap<K, V> {
  /**
   * {@inheritDoc}
   *

    TreeMultimap<String, Integer> multimap = TreeMultimap.create();
    multimap.put("google", 2);
    multimap.put("google", 6);
    multimap.put("foo", 3);
    multimap.put("foo", 1);
    multimap.put("foo", 7);
    multimap.put("tree", 4);
    multimap.put("tree", 0);
    return multimap;
  }

  public void testToString() {
    SetMultimap<String, Integer> multimap = create();

  public void testPutDuplicateValue() {
    List<Entry<K, V>> entries = copyToList(multimap().entries());

    for (Entry<K, V> entry : entries) {
      resetContainer();

      K k = entry.getKey();
      V v = entry.getValue();

      List<V> values = multimap().get(k);
      List<V> expectedValues = copyToList(values);

      assertTrue(multimap().put(k, v));
      expectedValues.add(v);
      assertGet(k, expectedValues);

      fail("putAll(Multimap<K, V>) succeeded on unmodifiable multimap");
    } catch (UnsupportedOperationException expected) {
    }
    assertMultimapRemainsUnmodified(multimap, originalEntries);

    // Test #remove()
    try {
      multimap.remove(sampleKey, sampleValue);
      fail("remove succeeded on unmodifiable multimap");
    } catch (UnsupportedOperationException expected) {
    }

    Multimap<String, Integer> multimap = ImmutableListMultimap.of();
    assertFalse(multimap.containsKey("foo"));
    assertFalse(multimap.containsValue(1));
    assertFalse(multimap.containsEntry("foo", 1));
    assertTrue(multimap.entries().isEmpty());
    assertTrue(multimap.equals(ArrayListMultimap.create()));
    assertEquals(Collections.emptyList(), multimap.get("foo"));
    assertEquals(0, multimap.hashCode());

  }

  public void testFilterFiltered() {
    Multimap<String, Integer> unfiltered = HashMultimap.create();
    unfiltered.put("foo", 55556);
    unfiltered.put("badkey", 1);
    unfiltered.put("foo", 1);
    Multimap<String, Integer> keyFiltered = Multimaps.filterKeys(unfiltered, KEY_PREDICATE);
    Multimap<String, Integer> filtered = Multimaps.filterValues(keyFiltered, VALUE_PREDICATE);
    assertEquals(1, filtered.size());

    multimap.put("foo", 3);
    assertTrue(multimap.removeAll("foo") instanceof RandomAccess);
    assertTrue(multimap.removeAll("bar") instanceof RandomAccess);
  }

  /** Confirm that replaceValues() returns a List implementing RandomAccess. */
  public void testReplaceValuesRandomAccess() {
    Multimap<String, Integer> multimap = create();
    multimap.put("foo", 1);
    multimap.put("foo", 3);

      @Override
      protected Iterator<String> newTargetIterator() {
        multimap = create();
        multimap.putAll("foo", asList(2, 3));
        multimap.putAll("bar", asList(4, 5));
        multimap.putAll("foo", asList(6));
        multimap.putAll("baz", asList(7, 8));
        multimap.putAll("dog", asList(9));
        multimap.putAll("bar", asList(10, 11));