Collection<V> collection) {
    if (collection instanceof SortedSet) {
      return Collections.unmodifiableSortedSet((SortedSet<V>) collection);
    } else if (collection instanceof Set) {
      return Collections.unmodifiableSet((Set<V>) collection);
    } else if (collection instanceof List) {
      return Collections.unmodifiableList((List<V>) collection);
    }

    checkNotNull(collection);
    return (collection instanceof EnumSet)
        ? EnumSet.complementOf((EnumSet<E>) collection)
        : makeComplementByHand(collection, type);
  }

  @J2ktIncompatible
  @GwtIncompatible
  private static <E extends Enum<E>> EnumSet<E> makeComplementByHand(
      Collection<E> collection, Class<E> type) {
    EnumSet<E> result = EnumSet.allOf(type);

import static com.google.common.truth.Truth.assertThat;
import static com.google.common.truth.Truth.assertWithMessage;
import static java.util.Arrays.asList;
import static java.util.Collections.emptyMap;
import static java.util.Collections.singleton;
import static java.util.Collections.singletonMap;

import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;

import static com.google.common.truth.Truth.assertThat;
import static java.util.Arrays.asList;
import static java.util.Collections.emptyList;
import static java.util.Collections.emptySet;
import static java.util.Collections.singleton;
import static java.util.Collections.singletonList;

import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;

import static com.google.common.truth.Truth.assertThat;
import static com.google.common.truth.Truth.assertWithMessage;
import static java.util.Arrays.asList;
import static java.util.Collections.emptyMap;
import static java.util.Collections.singleton;
import static java.util.Collections.singletonMap;

import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;

  }

  /**
   * Adapts an {@code Iterator} to the {@code Enumeration} interface.
   *
   * <p>The {@code Iterable} equivalent of this method is either {@link Collections#enumeration} (if
   * you have a {@link Collection}), or {@code Iterators.asEnumeration(collection.iterator())}.
   */
  // This is an adapter for cases in which users do need an Enumeration for whatever reason.
  @SuppressWarnings("JdkObsolete")

import static org.codelibs.core.stream.StreamUtil.split;

import java.io.IOException;
import java.net.URI;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeUnit;

            return num;
        }

        @Override
        public Map<String, String[]> getFields() {
            return Collections.emptyMap();
        }

        @Override
        public Map<String, String[]> getConditions() {
            return Collections.emptyMap();
        }

        /**
         * Gets the tags for filtering suggestions.

import java.net.PasswordAuthentication;
import java.net.Proxy;
import java.net.Proxy.Type;
import java.net.SocketAddress;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.Date;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.Set;

import java.net.InetSocketAddress;
import java.net.Socket;
import java.security.GeneralSecurityException;
import java.security.PrivilegedActionException;
import java.security.PrivilegedExceptionAction;
import java.util.Collections;
import java.util.EnumSet;
import java.util.List;
import java.util.Objects;
import java.util.Set;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.CopyOnWriteArrayList;