*/
  @CanIgnoreReturnValue
  boolean putAll(@ParametricNullness K key, Iterable<? extends V> values);

  /**
   * Stores all key-value pairs of {@code multimap} in this multimap, in the order returned by
   * {@code multimap.entries()}.
   *
   * @return {@code true} if the multimap changed
   */
  @CanIgnoreReturnValue
  boolean putAll(Multimap<? extends K, ? extends V> multimap);

      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) {
    }

    ListMultimap<String, Integer> multimap =
        Multimaps.synchronizedListMultimap(ArrayListMultimap.<String, Integer>create());
    multimap.putAll("foo", Arrays.asList(3, -1, 2, 4, 1));
    multimap.putAll("bar", Arrays.asList(1, 2, 3, 1));
    assertThat(multimap.removeAll("foo")).containsExactly(3, -1, 2, 4, 1).inOrder();
    assertFalse(multimap.containsKey("foo"));
    assertThat(multimap.replaceValues("bar", Arrays.asList(6, 5)))

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

  private static <K, V> ImmutableSetMultimap<K, V> copyOf(
      Multimap<? extends K, ? extends V> multimap,
      @CheckForNull Comparator<? super V> valueComparator) {

      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) {
    }

import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A {@code Multimap} that cannot hold duplicate key-value pairs. Adding a key-value pair that's
 * already in the multimap has no effect. See the {@link Multimap} documentation for information
 * common to all multimaps.
 *
 * <p>The {@link #get}, {@link #removeAll}, and {@link #replaceValues} methods each return a {@link

      Multimap<K, V> synchronizedMultimap(Multimap<K, V> multimap) {
    return Synchronized.multimap(multimap, null);
  }

  /**
   * Returns an unmodifiable view of the specified multimap. Query operations on the returned
   * multimap "read through" to the specified multimap, and attempts to modify the returned
   * multimap, either directly or through the multimap's views, result in an {@code

   *
   * @throws NullPointerException if any key or value in {@code multimap} is null
   */
  public static <K, V> ImmutableMultimap<K, V> copyOf(Multimap<? extends K, ? extends V> multimap) {
    if (multimap instanceof ImmutableMultimap) {
      @SuppressWarnings("unchecked") // safe since multimap is not writable
      ImmutableMultimap<K, V> kvMultimap = (ImmutableMultimap<K, V>) multimap;
      if (!kvMultimap.isPartialView()) {

    Multimap<String, Integer> multimap = createMultimap();
    assertTrue(multimap.containsKey("foo"));
    assertFalse(multimap.containsKey("cat"));
    assertTrue(multimap.containsValue(1));
    assertFalse(multimap.containsValue(5));
    assertTrue(multimap.containsEntry("foo", 1));
    assertFalse(multimap.containsEntry("cat", 1));
    assertFalse(multimap.containsEntry("foo", 5));
    assertFalse(multimap.entries().isEmpty());

   * Multimap}. The new multimap has the same {@link Multimap#entries()} iteration order as the
   * input multimap.
   *
   * @param multimap the multimap whose contents are copied to this multimap
   */
  public static <K extends @Nullable Object, V extends @Nullable Object>
      LinkedListMultimap<K, V> create(Multimap<? extends K, ? extends V> multimap) {
    return new LinkedListMultimap<>(multimap);