}
    };
  }

  @GwtIncompatible // NavigableSet
  private static <E extends @Nullable Object> NavigableSet<E> removeOnlyNavigableSet(
      NavigableSet<E> set) {
    return new ForwardingNavigableSet<E>() {
      @Override
      protected NavigableSet<E> delegate() {
        return set;
      }

      @Override

  @Nullable Entry<E> pollFirstEntry();

  @Nullable Entry<E> pollLastEntry();

  /**
   * Returns a {@link SortedSet} view of the distinct elements in this multiset. (Outside GWT, this
   * returns a {@code NavigableSet}.)
   */
  @Override
  SortedSet<E> elementSet();

  SortedMultiset<E> descendingMultiset();

  SortedMultiset<E> headMultiset(E upperBound, BoundType boundType);

  SortedMultiset<E> subMultiset(

import com.google.common.testing.EqualsTester;
import com.google.common.testing.ForwardingWrapperTester;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.NavigableSet;
import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/**

import com.google.common.testing.EqualsTester;
import com.google.common.testing.ForwardingWrapperTester;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.NavigableSet;
import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/**

 * limitations under the License.
 */

package com.google.common.collect;

import com.google.common.annotations.GwtCompatible;
import java.util.Comparator;
import java.util.Iterator;
import java.util.NavigableSet;
import org.jspecify.annotations.Nullable;

/**
 * A sorted multiset which forwards all its method calls to another sorted multiset. Subclasses

 * limitations under the License.
 */

package com.google.common.collect;

import com.google.common.annotations.GwtCompatible;
import java.util.Comparator;
import java.util.Iterator;
import java.util.NavigableSet;
import org.jspecify.annotations.Nullable;

/**
 * A sorted multiset which forwards all its method calls to another sorted multiset. Subclasses

      @Override
      protected @Nullable C computeNext(C previous) {
        return equalsOrThrow(previous, last) ? null : domain.next(previous);
      }
    };
  }

  @GwtIncompatible // NavigableSet
  @Override
  public UnmodifiableIterator<C> descendingIterator() {
    return new AbstractSequentialIterator<C>(last()) {
      final C first = first();

      @Override

import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.NavigableMap;
import java.util.NavigableSet;
import java.util.Objects;
import java.util.Set;
import java.util.SortedMap;
import java.util.SortedSet;
import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;

    }

    @Override
    <E extends @Nullable Object> Collection<E> unmodifiableCollectionSubclass(
        Collection<E> collection) {
      if (collection instanceof NavigableSet) {
        return Sets.unmodifiableNavigableSet((NavigableSet<E>) collection);
      } else if (collection instanceof SortedSet) {
        return Collections.unmodifiableSortedSet((SortedSet<E>) collection);
      } else if (collection instanceof Set) {

    }

    @Override
    <E extends @Nullable Object> Collection<E> unmodifiableCollectionSubclass(
        Collection<E> collection) {
      if (collection instanceof NavigableSet) {
        return Sets.unmodifiableNavigableSet((NavigableSet<E>) collection);
      } else if (collection instanceof SortedSet) {
        return Collections.unmodifiableSortedSet((SortedSet<E>) collection);
      } else if (collection instanceof Set) {