* ForwardingMultiset#entrySet}, and {@link ForwardingMultiset#remove(Object, int)}. In many
   * situations, you may wish to override {@link ForwardingMultiset#elementSet} to forward to this
   * implementation or a subclass thereof.
   *
   * @since 10.0
   */
  protected class StandardElementSet extends Multisets.ElementSet<E> {
    /** Constructor for use by subclasses. */
    public StandardElementSet() {}

    @Override

    /*
     * requireNonNull is not safe: Joiner.on(...).join(somethingThatContainsNull) will indeed throw.
     * However, Joiner.on(...).useForNull(...).join(somethingThatContainsNull) *is* safe -- because
     * it returns a subclass of Joiner that overrides this method to tolerate null inputs.
     *
     * Unfortunately, we don't distinguish between these two cases in our public API: Joiner.on(...)

        // The raw class isn't even a subclass.
      }
    }
    if (!spec.suppressGetSupertype()) {
      try {
        assertThat(getSupertype(paramType, TypeToken.of(returnType).getRawType()))
            .isNotEqualTo(returnType);
      } catch (IllegalArgumentException notSubtype2) {
        // The raw class isn't even a subclass.
      }
    }
    return null;
  }

 *
 * <p>For details about this hack, see {@code GwtSerializationDependencies}, which takes the same
 * approach but with a subclass rather than a superclass.
 *
 * <p>TODO(cpovirk): Consider applying this subclass approach to our other types.
 */
@GwtCompatible(emulated = true)
abstract class HashMultimapGwtSerializationDependencies<K, V> extends AbstractSetMultimap<K, V> {

 *
 * <p>For details about this hack, see {@code GwtSerializationDependencies}, which takes the same
 * approach but with a subclass rather than a superclass.
 *
 * <p>TODO(cpovirk): Consider applying this subclass approach to our other types.
 */
@GwtCompatible(emulated = true)
abstract class LinkedHashMultimapGwtSerializationDependencies<K, V>
    extends AbstractSetMultimap<K, V> {

 * interface-specific subclass of {@code ForwardingObject}, such as {@link ForwardingList}, to
 * preserve equality behavior, or override {@code equals} directly.
 *
 * <p>The {@code toString} method is forwarded to the delegate. Although this class does not
 * implement {@link Serializable}, a serializable subclass may be created since this class has a
 * parameter-less constructor.
 *

   * {@link ForwardingMap#entrySet}. In many cases, you may wish to override {@link
   * ForwardingMap#keySet} to forward to this implementation or a subclass thereof.
   *
   * @since 10.0
   */
  protected class StandardKeySet extends Maps.KeySet<K, V> {
    /** Constructor for use by subclasses. */
    public StandardKeySet() {
      super(ForwardingMap.this);

              public void remove() {
                throw new IllegalStateException() {
                  /* subclass */
                };
              }

              @Override
              public Integer next() {
                throw new NoSuchElementException() {
                  /* subclass */
                };
              }

              @Override
              public boolean hasNext() {

import com.google.common.collect.Iterables;
import com.google.common.testing.ForwardingWrapperTester;
import java.lang.reflect.Method;
import java.util.Arrays;

/**
 * Tester for typical subclass of {@link ForwardingObject} by using Mockito.
 *
 * @author Ben Yu
 */
final class ForwardingObjectTester {

  private static final Method DELEGATE_METHOD;

  static {
    try {

 * single row key may or may not be ordered, depending on the implementation. When rows and columns
 * are both sorted, it's easier to use the {@link TreeBasedTable} subclass.
 *
 * <p>The {@link #rowKeySet} method returns a {@link SortedSet} and the {@link #rowMap} method
 * returns a {@link SortedMap}, instead of the {@link Set} and {@link Map} specified by the {@link
 * Table} interface.
 *