@GwtCompatible
public class ConflictingRequirementsException extends Exception {
  private final Set<Feature<?>> conflicts;
  private final Object source;

  public ConflictingRequirementsException(
      String message, Set<Feature<?>> conflicts, Object source) {
    super(message);
    this.conflicts = conflicts;
    this.source = source;
  }

  public Set<Feature<?>> getConflicts() {
    return conflicts;
  }

  public Object getSource() {

import com.google.common.collect.testing.TestListGenerator;
import com.google.common.collect.testing.features.CollectionFeature;
import com.google.common.collect.testing.features.CollectionSize;
import com.google.common.collect.testing.features.Feature;
import com.google.common.collect.testing.features.ListFeature;
import java.util.Collections;
import java.util.EnumSet;
import java.util.List;
import java.util.Map.Entry;

    List<Feature<?>> features = new ArrayList<>();
    features.add(NoRecurse.SUBMAP);
    features.addAll(parentBuilder.getFeatures());

    return newBuilderUsing(delegate, to, from)
        .named(parentBuilder.getName() + " subMap " + from + "-" + to)
        .withFeatures(features)
        .suppressing(parentBuilder.getSuppressedTests())

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

  ListFeature(Feature<? super List>... implied) {
    this.implied = copyToSet(implied);
  }

  @Override
  public Set<Feature<? super List>> getImpliedFeatures() {
    return implied;
  }

  @Retention(RetentionPolicy.RUNTIME)
  @Inherited
  @TesterAnnotation
  public @interface Require {

@GwtCompatible
public enum MultimapFeature implements Feature<Multimap> {
  VALUE_COLLECTIONS_SUPPORT_ITERATOR_REMOVE;

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

  MultimapFeature(Feature<? super Multimap>... implied) {
    this.implied = copyToSet(implied);
  }

  @Override
  public Set<Feature<? super Multimap>> getImpliedFeatures() {
    return implied;
  }

@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
  public Set<Feature<? super Set>> getImpliedFeatures() {
    return implied;
  }

    // Copy this set, so we can modify it.
    Set<Feature<?>> features = copyToSet(getFeatures());
    @SuppressWarnings("rawtypes") // class literals
    List<Class<? extends AbstractTester>> testers = getTesters();

    logger.fine(" Testing: " + name);

    // Split out all the specified sizes.
    Set<Feature<?>> sizesToTest = Helpers.<Feature<?>>copyToSet(CollectionSize.values());
    sizesToTest.retainAll(features);

          annotationClass.getDeclaringClass(),
          returnType.getComponentType());
    }
  }

  // This is public so that tests for Feature enums we haven't yet imagined
  // can reuse it.
  public static <E extends Enum<?> & Feature<?>> void assertGoodFeatureEnum(
      Class<E> featureEnumClass) {
    Class<?>[] classes = featureEnumClass.getDeclaredClasses();
    for (Class<?> containedClass : classes) {

   * but one.
   */
  REJECTS_DUPLICATES_AT_CREATION,

  GENERAL_PURPOSE(SUPPORTS_PUT, SUPPORTS_REMOVE);

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

  MapFeature(Feature<? super Map>... implied) {
    this.implied = copyToSet(implied);
  }

  @Override
  public Set<Feature<? super Map>> getImpliedFeatures() {
    return implied;
  }

  @Retention(RetentionPolicy.RUNTIME)
  @Inherited
  @TesterAnnotation

    @Override
    public Iterable<E> order(List<E> insertionOrder) {
      return gen.order(insertionOrder);
    }
  }

  private static Set<Feature<?>> computeReserializedCollectionFeatures(Set<Feature<?>> features) {
    Set<Feature<?>> derivedFeatures = new HashSet<>(features);
    derivedFeatures.remove(SERIALIZABLE);
    derivedFeatures.remove(SERIALIZABLE_INCLUDING_VIEWS);
    return derivedFeatures;
  }