crawler1.awaitTermination();
            crawler2.awaitTermination();

            assertEquals(maxCount, dataService.getCount(sessionId1));
            assertEquals(maxCount, dataService.getCount(sessionId2));

            UrlQueue urlQueue;
            while ((urlQueue = urlQueueService.poll(sessionId1)) != null) {

    if (!entryIterator.hasNext()) {
      return null;
    }
    Entry<E> entry = entryIterator.next();
    return Multisets.immutableEntry(entry.getElement(), entry.getCount());
  }

  @Override
  @CheckForNull
  public Entry<E> lastEntry() {
    return delegate().lastEntry();
  }

  /**
   * A sensible definition of {@link #lastEntry()} in terms of {@code

    LocalCache<Object, Object> map = makeLocalCache(createCacheBuilder());
    assertEquals(0, loader.getCount());

    Object key = new Object();
    Object value = map.get(key, loader);
    assertEquals(1, loader.getCount());
    assertEquals(value, map.get(key, loader));
    assertEquals(1, loader.getCount());
  }

  public void testRecordReadOnCompute() throws ExecutionException {

    LocalCache<Object, Object> map = makeLocalCache(createCacheBuilder());
    assertEquals(0, loader.getCount());

    Object key = new Object();
    Object value = map.get(key, loader);
    assertEquals(1, loader.getCount());
    assertEquals(value, map.get(key, loader));
    assertEquals(1, loader.getCount());
  }

  public void testRecordReadOnCompute() throws ExecutionException {

    }

    @Override
    public int count(@Nullable Object element) {
      for (Entry<E> entry : entrySet()) {
        if (Objects.equal(entry.getElement(), element)) {
          return entry.getCount();
        }
      }
      return 0;
    }

    @Override
    public int add(E element, int occurrences) {
      checkArgument(occurrences >= 0);
      Integer frequency = backingMap.get(element);

            arMap.put(accessResult.getUrl(), accessResult);
        }

    }

    /*
     * (non-Javadoc)
     *
     * @see org.codelibs.fess.crawler.service.DataService#getCount(java.lang.String)
     */
    @Override
    public int getCount(final String sessionId) {
        return dataHelper.getAccessResultMap(sessionId).size();
    }

    /*
     * (non-Javadoc)
     *

     * 
     * @param config
     */
    public SmbComWriteAndXResponse ( Configuration config ) {
        super(config);
    }


    /**
     * @return the count
     */
    public final long getCount () {
        return this.count;
    }


    @Override
    protected int writeParameterWordsWireFormat ( byte[] dst, int dstIndex ) {
        return 0;
    }


    @Override

   * The count is accessible via {@link #getCount}.
   */
  static class CountingLoader extends CacheLoader<Object, Object> {
    private final AtomicInteger count = new AtomicInteger();

    @Override
    public Object load(Object from) {
      count.incrementAndGet();
      return new Object();
    }

    public int getCount() {
      return count.get();
    }
  }

      for (int j = 0; j < numListeners; j++) {
        list.add(listener, directExecutor());
        returnValue += listenerLatch.getCount();
      }
      list.execute();
      returnValue += listenerLatch.getCount();
    }
    return returnValue;
  }

  @Benchmark
  int executeThenAdd_singleThreaded(int reps) {
    int returnValue = 0;

 *
 */
public interface DataService<RESULT extends AccessResult<?>> {

    void store(RESULT accessResult);

    void update(RESULT accessResult);

    void update(List<RESULT> accessResult);

    int getCount(String sessionId);

    void delete(String sessionId);

    void deleteAll();

    RESULT getAccessResult(String sessionId, String url);

    List<RESULT> getAccessResultList(String url, boolean hasData);