/** Clears the reference queues used by this segment, if any. */
    void maybeClearReferenceQueues() {}

    /** Sets the value of the given {@code entry}. */
    void setValue(E entry, V value) {
      this.map.entryHelper.setValue(self(), entry, value);
    }

    /** Returns a copy of the given {@code entry}. */
    @CheckForNull
    E copyEntry(E original, E newNext) {

    /** Clears the reference queues used by this segment, if any. */
    void maybeClearReferenceQueues() {}

    /** Sets the value of the given {@code entry}. */
    void setValue(E entry, V value) {
      this.map.entryHelper.setValue(self(), entry, value);
    }

    /** Returns a copy of the given {@code entry}. */
    @CheckForNull
    E copyEntry(E original, E newNext) {

            if (fields != null) {
                final Map<String, Object> docMap = fields.entrySet().stream()
                        .collect(Collectors.toMap(Entry<String, DocumentField>::getKey, e -> (Object) e.getValue().getValues()));
                docMap.put(fessConfig.getIndexFieldId(), hit.getId());
                docMap.put(fessConfig.getIndexFieldVersion(), hit.getVersion());

    @Override
    public V getValue() {
      synchronized (mutex) {
        return delegate().getValue();
      }
    }

    @Override
    public V setValue(V value) {
      synchronized (mutex) {
        return delegate().setValue(value);
      }
    }

    private static final long serialVersionUID = 0;
  }

    @Override
    public V getValue() {
      synchronized (mutex) {
        return delegate().getValue();
      }
    }

    @Override
    public V setValue(V value) {
      synchronized (mutex) {
        return delegate().setValue(value);
      }
    }

    private static final long serialVersionUID = 0;
  }

    }
    return Collections.unmodifiableCollection(collection);
  }

  /**
   * Returns an unmodifiable view of the specified collection of entries. The {@link Entry#setValue}
   * operation throws an {@link UnsupportedOperationException}. If the specified collection is a
   * {@code Set}, the returned collection is also a {@code Set}.
   *