return null;
        }

        @Override
        public boolean isEqualNode(Node arg) {
            return false;
        }

        @Override
        public Object getFeature(String feature, String version) {
            return null;
        }

        @Override
        public Object setUserData(String key, Object data, org.w3c.dom.UserDataHandler handler) {
            return null;

 */
@SuppressWarnings("rawtypes") // maybe avoidable if we rework the whole package?
@GwtCompatible
public enum SetFeature implements Feature<Set> {
  GENERAL_PURPOSE(CollectionFeature.GENERAL_PURPOSE);

  private final Set<Feature<? super Set>> implied;

  SetFeature(Feature<? super Set>... implied) {
    this.implied = copyToSet(implied);
  }

  @Override

 */
@SuppressWarnings("rawtypes") // maybe avoidable if we rework the whole package?
@GwtCompatible
public enum SetFeature implements Feature<Set> {
  GENERAL_PURPOSE(CollectionFeature.GENERAL_PURPOSE);

  private final Set<Feature<? super Set>> implied;

  SetFeature(Feature<? super Set>... implied) {
    this.implied = copyToSet(implied);
  }

  @Override

import com.google.common.annotations.GwtIncompatible;
import com.google.common.collect.testing.features.CollectionFeature;
import com.google.common.collect.testing.features.CollectionSize;
import com.google.common.collect.testing.features.SetFeature;
import java.io.Serializable;
import java.lang.reflect.Method;
import java.util.AbstractSet;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.EnumSet;

    if (!parentBuilder.getFeatures().contains(NoRecurse.DESCENDING)) {
      derivedSuites.add(createDescendingSuite(parentBuilder));
    }

    if (parentBuilder.getFeatures().contains(SERIALIZABLE)) {
      derivedSuites.add(createReserializedSuite(parentBuilder));
    }

    if (!parentBuilder.getFeatures().contains(NoRecurse.SUBMULTISET)) {

    testers.add(SortedMapNavigationTester.class);
    return testers;
  }

  @Override
  public TestSuite createTestSuite() {
    if (!getFeatures().contains(KNOWN_ORDER)) {
      List<Feature<?>> features = copyToList(getFeatures());
      features.add(KNOWN_ORDER);
      withFeatures(features);
    }
    return super.createTestSuite();
  }

  @Override

        final SAXParserFactory factory = SAXParserFactory.newInstance();
        try {
            factory.setFeature(XMLConstants.FEATURE_SECURE_PROCESSING, true);
            factory.setFeature("http://xml.org/sax/features/external-general-entities", false);
            factory.setFeature("http://xml.org/sax/features/external-parameter-entities", false);
        } catch (SAXNotRecognizedException | SAXNotSupportedException e) {

    if (!parentBuilder.getFeatures().contains(NoRecurse.NO_ENTRY_SET)) {
      derivedSuites.add(
          SetTestSuiteBuilder.using(new EntrySetGenerator<E>(parentBuilder.getSubjectGenerator()))
              .named(getName() + ".entrySet")
              .withFeatures(computeEntrySetFeatures(parentBuilder.getFeatures()))
              .suppressing(parentBuilder.getSuppressedTests())

import com.google.common.annotations.GwtIncompatible;
import com.google.common.collect.testing.features.CollectionFeature;
import com.google.common.collect.testing.features.CollectionSize;
import com.google.common.collect.testing.features.SetFeature;
import java.io.Serializable;
import java.lang.reflect.Method;
import java.util.AbstractSet;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.EnumSet;

    if (parentBuilder.getFeatures().contains(SERIALIZABLE)) {
      derivedSuites.add(
          CollectionTestSuiteBuilder.using(
                  new ReserializedCollectionGenerator<E>(parentBuilder.getSubjectGenerator()))
              .named(getName() + " reserialized")
              .withFeatures(computeReserializedCollectionFeatures(parentBuilder.getFeatures()))