*
 * @author Louis Wasserman
 */
@ElementTypesAreNonnullByDefault
public abstract class ForwardingSortedMultiset<E extends @Nullable Object>
    extends ForwardingMultiset<E> implements SortedMultiset<E> {
  /** Constructor for use by subclasses. */
  protected ForwardingSortedMultiset() {}

  @Override
  protected abstract SortedMultiset<E> delegate();

  @Override
  public SortedSet<E> elementSet() {

 * @since 15.0
 */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
public abstract class ForwardingSortedMultiset<E extends @Nullable Object>
    extends ForwardingMultiset<E> implements SortedMultiset<E> {
  /** Constructor for use by subclasses. */
  protected ForwardingSortedMultiset() {}

  @Override
  protected abstract SortedMultiset<E> delegate();

  @Override
  public NavigableSet<E> elementSet() {

import junit.framework.TestSuite;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Tests for {@link ForwardingSortedMultiset}.
 *
 * @author Louis Wasserman
 */
public class ForwardingSortedMultisetTest extends TestCase {
  static class StandardImplForwardingSortedMultiset<E> extends ForwardingSortedMultiset<E> {
    private final SortedMultiset<E> backingMultiset;

import junit.framework.TestSuite;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Tests for {@link ForwardingSortedMultiset}.
 *
 * @author Louis Wasserman
 */
public class ForwardingSortedMultisetTest extends TestCase {
  static class StandardImplForwardingSortedMultiset<E> extends ForwardingSortedMultiset<E> {
    private final SortedMultiset<E> backingMultiset;