int expectedHashCode = 0;
    for (E element : getSampleElements()) {
      expectedHashCode += ((element == null) ? 0 : element.hashCode());
    }
    assertEquals(
        "A Set's hashCode() should be the sum of those of its elements.",
        expectedHashCode,
        getSet().hashCode());
  }

  @CollectionSize.Require(absent = CollectionSize.ZERO)
  @CollectionFeature.Require(ALLOWS_NULL_VALUES)

    }
  }

  /**
   * Verifies that a collection is immutable.
   *
   * <p>A collection is considered immutable if:
   *
   * <ol>
   *   <li>All its mutation methods result in UnsupportedOperationException, and do not change the
   *       underlying contents.
   *   <li>All methods that return objects that can indirectly mutate the collection throw

  }

  /**
   * Returns an unmodifiable view of the difference of two multisets. In the returned multiset, the
   * count of each element is the result of the <i>zero-truncated subtraction</i> of its count in
   * the second multiset from its count in the first multiset, with elements that would have a count
   * of 0 not included. The iteration order of the returned multiset matches that of the element set

   *     despite its deprecation. But if you can choose your hash function, avoid MD5, which is
   *     neither fast nor secure. As of January 2017, we suggest:
   *     <ul>
   *       <li>For security:
   *           {@link Hashing#sha256} or a higher-level API.
   *       <li>For speed: {@link Hashing#goodFastHash}, though see its docs for caveats.
   *     </ul>
   */
  @Deprecated

 * detailed at {@link ImmutableCollection}.
 *
 * <p><b>Warning:</b> As in all {@link SetMultimap}s, do not modify either a key <i>or a value</i>
 * of a {@code ImmutableSetMultimap} in a way that affects its {@link Object#equals} behavior.
 * Undefined behavior and bugs will result.
 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/ImmutableCollectionsExplained">immutable collections</a>.

    return list.get(list.size() - 1);
  }

  /**
   * Returns a view of {@code iterable} that skips its first {@code numberToSkip} elements. If
   * {@code iterable} contains fewer than {@code numberToSkip} elements, the returned iterable skips
   * all of its elements.
   *
   * <p>Modifications to the underlying {@link Iterable} before a call to {@code iterator()} are

    }
    return throwable;
  }

  /**
   * Gets a {@code Throwable} cause chain as a list. The first entry in the list will be {@code
   * throwable} followed by its cause hierarchy. Note that this is a snapshot of the cause chain and
   * will not reflect any subsequent changes to the cause chain.
   *

   * cannot implement that interface in source code in a way that will compile on both Java 7 and
   * Java 8. If we include the {@code getAnnotatedBounds()} method then its return type means it
   * won't compile on Java 7, while if we don't include the method then the compiler will complain
   * that an abstract method is unimplemented. So instead we use a dynamic proxy to get an

    }
    return throwable;
  }

  /**
   * Gets a {@code Throwable} cause chain as a list. The first entry in the list will be {@code
   * throwable} followed by its cause hierarchy. Note that this is a snapshot of the cause chain and
   * will not reflect any subsequent changes to the cause chain.
   *

import java.util.Map;
import java.util.Map.Entry;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A map entry which forwards all its method calls to another map entry. Subclasses should override
 * one or more methods to modify the behavior of the backing map entry as desired per the <a
 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.