assertTrue(multimap().asMap().get(key) instanceof List);
    }
  }

  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testAsMapRemoveImplementsList() {
    List<K> keys = new ArrayList<>(multimap().keySet());
    for (K key : keys) {
      resetCollection();
      assertTrue(multimap().asMap().remove(key) instanceof List);
    }
  }

  @CollectionSize.Require(SEVERAL)
  public void testEquals() {

        assertNotNull(hmac);
    }

    @Test
    void testConstructorWithLongKey() {
        // Test constructor with a key longer than BLOCK_LENGTH (64 bytes)
        // HMACT64 truncates keys at 64 bytes
        HMACT64 hmac = new HMACT64(LONG_TEST_KEY);
        assertNotNull(hmac);
    }

    @Test
    void testConstructorWithShortKey() {

    assertEquals(multimap(), getSubjectGenerator().create());
    assertEmpty(multimap().entries());
    assertEmpty(multimap().asMap());
    assertEmpty(multimap().keySet());
    assertEmpty(multimap().keys());
    assertEmpty(multimap().values());
    for (K key : sampleKeys()) {
      assertGet(key);
    }
  }

  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testClear() {
    multimap().clear();

        multimap.putAll("bar", asList(4, 5));
        multimap.putAll("foo", asList(6));
        return multimap.keys().iterator();
      }

      @Override
      protected void verify(List<String> elements) {
        assertEquals(elements, new ArrayList<>(multimap.keys()));
      }
    }.test();
  }

  @GwtIncompatible // unreasonably slow
  public void testValuesIteration() {

// Package crypto implements AWS S3 related cryptographic building blocks
// for implementing Server-Side-Encryption (SSE-S3) and Server-Side-Encryption
// with customer provided keys (SSE-C).
//
// All objects are encrypted with an unique and randomly generated 'ObjectKey'.
// The ObjectKey itself is never stored in plaintext. Instead it is only stored

 *       as that of its keys. This is sometimes called an "invertible map," since the restriction on
 *       values enables it to support an {@linkplain BiMap#inverse inverse view} -- which is another
 *       instance of {@code BiMap}.
 *   <dt>{@link Table}
 *   <dd>A new type, which is similar to {@link java.util.Map}, but which indexes its values by an
 *       ordered pair of keys, a row key and column key.
 *   <dt>{@link Multiset}

 *
 * <p><b>Note:</b> by default, the returned cache uses equality comparisons (the {@link
 * Object#equals equals} method) to determine equality for keys or values. However, if {@link
 * #weakKeys} was specified, the cache uses identity ({@code ==}) comparisons instead for keys.
 * Likewise, if {@link #weakValues} or {@link #softValues} was specified, the cache uses identity
 * comparisons for values.
 *

     */
    public String[] getValues(final String key) {
        return metadata.get(key);
    }

    /**
     * Gets the set of all metadata keys.
     *
     * @return the set of metadata keys
     */
    public Set<String> getKeySet() {
        return metadata.keySet();
    }

    /**
     * Gets the extracted content.
     *
     * @return the extracted content

 * </ul>
 *
 * <p>For complex XML structures, combining can also be done based on:</p>
 * <ul>
 *   <li>ID: Using the {@code combine.id} attribute</li>
 *   <li>Keys: Using the {@code combine.keys} attribute with comma-separated key names</li>
 * </ul>
 *
 * @since 4.0.0
 */
public abstract class XmlService {

    /** Attribute name controlling how child elements are combined */

 *
 * <p>This implementation is heavily derived from revision 1.96 of <a
 * href="http://tinyurl.com/ConcurrentHashMap">ConcurrentHashMap.java</a>.
 *
 * @param <K> the type of the keys in the map
 * @param <V> the type of the values in the map
 * @param <E> the type of the {@link InternalEntry} entry implementation used internally
 * @param <S> the type of the {@link Segment} entry implementation used internally