* advice in {@link #concat(Iterable...)}.
   *
   * @since 20.0
   */
  public static <T extends @Nullable Object> FluentIterable<T> concat(
      Iterable<? extends T> a,
      Iterable<? extends T> b,
      Iterable<? extends T> c,
      Iterable<? extends T> d) {
    return concatNoDefensiveCopy(a, b, c, d);
  }

  /**

  @SafeVarargs
  public static <T extends @Nullable Object> Stream<T> concat(Stream<? extends T>... streams) {
    // TODO(lowasser): consider an implementation that can support SUBSIZED
    boolean isParallel = false;
    int characteristics = Spliterator.ORDERED | Spliterator.SIZED | Spliterator.NONNULL;
    long estimatedSize = 0L;
    ImmutableList.Builder<Spliterator<? extends T>> splitrsBuilder =

    }

    protected <ENTITY extends WebAuthentication> ENTITY doSelectByPK(String id, Class<? extends ENTITY> tp) {
        return doSelectEntity(xprepareCBAsPK(id), tp);
    }

    protected WebAuthenticationCB xprepareCBAsPK(String id) {
        assertObjectNotNull("id", id);
        return newConditionBean().acceptPK(id);
    }

    }

    protected <ENTITY extends FileConfig> ENTITY doSelectByPK(String id, Class<? extends ENTITY> tp) {
        return doSelectEntity(xprepareCBAsPK(id), tp);
    }

    protected FileConfigCB xprepareCBAsPK(String id) {
        assertObjectNotNull("id", id);
        return newConditionBean().acceptPK(id);
    }

import jcifs.smb.SmbTreeInternal;
import jcifs.util.transport.TransportException;


/**
 * @author mbechler
 *
 */
@RunWith ( Parameterized.class )
@SuppressWarnings ( "javadoc" )
public class ConcurrencyTest extends BaseCIFSTest {

    static final Logger log = LoggerFactory.getLogger(ConcurrencyTest.class);
    private ExecutorService executor;


    public ConcurrencyTest ( String name, Map<String, String> properties ) {

   */
  @SuppressWarnings("rawtypes") // https://github.com/google/guava/issues/989
  public static <K extends Comparable, V extends Comparable> TreeMultimap<K, V> create(
      Multimap<? extends K, ? extends V> multimap) {
    return new TreeMultimap<>(Ordering.natural(), Ordering.natural(), multimap);
  }

  }

  // Bulk Operations

  @Override
  public void putAll(Map<? extends K, ? extends V> map) {
    for (Entry<? extends K, ? extends V> entry : map.entrySet()) {
      put(entry.getKey(), entry.getValue());
    }
  }

  @Override
  public void replaceAll(BiFunction<? super K, ? super V, ? extends V> function) {
    this.delegate.replaceAll(function);
    inverse.delegate.clear();

     */
    public static <T extends Map<String, Object>> T copyMapToNewMap(final Map<String, ? extends Object> src,
            final Class<? extends T> destClass) {
        return copyMapToNewMap(src, destClass, DEFAULT_OPTIONS);
    }

    public static <T extends Map<String, Object>> T copyMapToNewMap(final Map<String, ? extends Object> src,
            final Class<? extends T> destClass, final Consumer<CopyOptions> option) {

    }

    protected <ENTITY extends SearchLog> ENTITY doSelectByPK(String id, Class<? extends ENTITY> tp) {
        return doSelectEntity(xprepareCBAsPK(id), tp);
    }

    protected SearchLogCB xprepareCBAsPK(String id) {
        assertObjectNotNull("id", id);
        return newConditionBean().acceptPK(id);
    }

  @IgnoreJRERequirement // Users will use this only if they're already using streams.
  public static <T extends @Nullable Object, K extends Comparable<? super K>, V>
      Collector<T, ?, ImmutableRangeMap<K, V>> toImmutableRangeMap(
          Function<? super T, Range<K>> keyFunction,
          Function<? super T, ? extends V> valueFunction) {
    return CollectCollectors.toImmutableRangeMap(keyFunction, valueFunction);
  }

  /**