Collection<Entry<K, V>> entries = multimap().entries();
    assertFalse(entries.contains(mapEntry(k3(), v3())));
    multimap().put(k3(), v3());
    assertContains(entries, mapEntry(k3(), v3()));
  }

  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require(SUPPORTS_PUT)
  public void testPutPresentKeyPropagatesToEntries() {
    Collection<Entry<K, V>> entries = multimap().entries();

    Collection<Entry<K, V>> entries = multimap().entries();
    assertFalse(entries.contains(mapEntry(k3(), v3())));
    multimap().put(k3(), v3());
    assertContains(entries, mapEntry(k3(), v3()));
  }

  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require(SUPPORTS_PUT)
  public void testPutPresentKeyPropagatesToEntries() {
    Collection<Entry<K, V>> entries = multimap().entries();

  }

  @Override
  public int count(@Nullable Object element) {
    return forward.count(element);
  }

  @Override
  public @Nullable Entry<E> firstEntry() {
    return forward.lastEntry();
  }

  @Override
  public @Nullable Entry<E> lastEntry() {
    return forward.firstEntry();
  }

  @Override
  public int size() {
    return forward.size();
  }

  @Override

                  assertNull(k);
                  assertEquals(getValueForNullKey(), v);
                  return v3();
                }));

    Entry<K, V>[] expected = createArrayWithNullKey();
    expected[getNullLocation()] = entry(null, v3());
    expectContents(expected);
  }

  @MapFeature.Require({SUPPORTS_PUT, ALLOWS_NULL_KEYS})
  public void testComputeIfPresent_nullKeySupportedAbsent() {

  }

  /**
   * Returns true if this entry has no bucket links and can safely be reused as a terminal entry in
   * a bucket in another map.
   */
  boolean isReusable() {
    return true;
  }

  static class NonTerminalImmutableMapEntry<K, V> extends ImmutableMapEntry<K, V> {
    /*
     * Yes, we sometimes set nextInKeyBucket to null, even for this "non-terminal" entry. We don't

        if (this.options != null) {
            for (final Entry<String, Object> entry : this.options.entrySet()) {
                ret.append(",").append(entry.getKey()).append("=").append(entry.getValue());
            }
        }
        ret.append("]");
        return ret.toString();
    }

/**
 * The UrlQueue interface represents a queue of URLs to be processed by a web crawler.
 * It provides methods to get and set various properties of a URL queue entry.
 *
 * @param <IDTYPE> the type of the identifier for the URL queue entry
 */
public interface UrlQueue<IDTYPE> {

    /**
     * Retrieves the unique identifier of the URL queue.
     *
     * @return the unique identifier of type IDTYPE.
     */

@SuppressWarnings("JUnit4ClassUsedInJUnit3")
public class MultimapKeySetTester<K, V> extends AbstractMultimapTester<K, V, Multimap<K, V>> {
  public void testKeySet() {
    for (Entry<K, V> entry : getSampleElements()) {
      assertTrue(multimap().keySet().contains(entry.getKey()));
    }
  }

  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require(ALLOWS_NULL_KEYS)
  public void testKeySetContainsNullKeyPresent() {

            final StringBuilder formBuf = new StringBuilder(100);
            for (final Map.Entry<String, String> entry : paramMap.entrySet()) {
                queryBuf.append('&');
                queryBuf.append(URLUtil.encode(entry.getValue(), Constants.UTF_8));
                queryBuf.append('=');
                queryBuf.append(URLUtil.encode(entry.getKey(), Constants.UTF_8));
                formBuf.append("<input type=\"hidden\" name=\"");

   *
   * @return the number of elements in this queue
   */
  @CanIgnoreReturnValue
  @Override
  public int size() {
    Monitor monitor = this.monitor;
    monitor.enter();
    try {
      return count;
    } finally {
      monitor.leave();
    }
  }

  // this doc comment is a modified copy of the inherited doc comment,
  // without the reference to unlimited queues.