}
        return ComponentUtil.getDocumentHelper().encodeSimilarDocHash(input);
    }

    /**
     * Joins array or list elements into a single space-separated string.
     *
     * @param input the input object (String[], List, or String)
     * @return joined string with elements separated by spaces, or empty string if invalid input
     */
    public static String join(final Object input) {
        String[] values = null;

        return false;
      }
      int i = parent.start;
      // Since `that` is very likely RandomAccess we could avoid allocating this iterator...
      for (Object element : that) {
        if (!(element instanceof Long) || parent.array[i++] != (Long) element) {
          return false;
        }
      }
      return true;
    }

    // Because we happen to use the same formula. If that changes, just don't override this.

      @GwtIncompatible @J2ktIncompatible private static final long serialVersionUID = 1L;

      @Override
      public boolean contains(@Nullable Object element) {
        Preconditions.checkNotNull(element);
        return super.contains(element);
      }
    }
    Collection<Integer> nums = new CollectionThatThrowsNullPointerException<>();
    Predicate<@Nullable Integer> isFalse = Predicates.in(nums);

@SuppressWarnings("JUnit4ClassUsedInJUnit3")
public class CollectionRetainAllTester<E> extends AbstractCollectionTester<E> {

  /** A collection of elements to retain, along with a description for use in failure messages. */
  private final class Target {
    private final Collection<E> toRetain;
    private final String description;

    multimap().replaceValues(k3(), values);
    assertGet(k3(), values);
    assertEquals(size + values.size(), multimap().size());
  }

  @SuppressWarnings("EmptyList") // ImmutableList doesn't support nullable element types
  @MapFeature.Require({SUPPORTS_PUT, SUPPORTS_REMOVE})
  public void testReplaceValuesWithEmpty() {
    int size = multimap().size();
    List<V> oldValues = new ArrayList<>(multimap().get(k0()));

  public void testRemove_unsupported() {
    assertThrows(UnsupportedOperationException.class, () -> getMap().remove(k0()));
    expectUnchanged();
    assertEquals("remove(present) should not remove the element", v0(), get(k0()));
  }

  @MapFeature.Require(absent = SUPPORTS_REMOVE)
  public void testRemove_unsupportedNotPresent() {
    try {
      assertNull(

  protected AbstractListMultimap(Map<K, Collection<V>> map) {
    super(map);
  }

  @Override
  abstract List<V> createCollection();

  @SuppressWarnings("EmptyList") // ImmutableList doesn't support nullable element types
  @Override
  List<V> createUnmodifiableEmptyCollection() {
    return emptyList();
  }

  @Override
  <E extends @Nullable Object> Collection<E> unmodifiableCollectionSubclass(

    }
    return ImmutableEnumMap.asImmutable(enumMap);
  }

  /**
   * Returns a {@link Collector} that accumulates elements into an {@code ImmutableMap} whose keys
   * and values are the result of applying the provided mapping functions to the input elements. The
   * resulting implementation is specialized for enum key types. The returned map and its views will

    }
    return ImmutableEnumMap.asImmutable(enumMap);
  }

  /**
   * Returns a {@link Collector} that accumulates elements into an {@code ImmutableMap} whose keys
   * and values are the result of applying the provided mapping functions to the input elements. The
   * resulting implementation is specialized for enum key types. The returned map and its views will

public abstract class ArrayBasedUnicodeEscaper extends UnicodeEscaper {
  // The replacement array (see ArrayBasedEscaperMap).
  private final char[][] replacements;
  // The number of elements in the replacement array.
  private final int replacementsLength;
  // The first code point in the safe range.
  private final int safeMin;
  // The last code point in the safe range.
  private final int safeMax;