*
   * <p>Elements are copied from the argument collection as if by {@code collection.toArray()}.
   * Calling this method is as thread-safe as calling that method.
   *
   * @param collection a collection of {@code Character} objects
   * @return an array containing the same values as {@code collection}, in the same order, converted
   *     to primitives
   * @throws NullPointerException if {@code collection} or any of its elements is null
   */

   *
   * <p>Elements are copied from the argument collection as if by {@code collection.toArray()}.
   * Calling this method is as thread-safe as calling that method.
   *
   * @param collection a collection of {@code Number} instances
   * @return an array containing the same values as {@code collection}, in the same order, converted
   *     to primitives
   * @throws NullPointerException if {@code collection} or any of its elements is null

   *
   * <p>Elements are copied from the argument collection as if by {@code collection.toArray()}.
   * Calling this method is as thread-safe as calling that method.
   *
   * @param collection a collection of {@code Number} instances
   * @return an array containing the same values as {@code collection}, in the same order, converted
   *     to primitives
   * @throws NullPointerException if {@code collection} or any of its elements is null

   */
  boolean hasEdgeConnecting(EndpointPair<N> endpoints);

  //
  // Network identity
  //

  /**
   * Returns {@code true} iff {@code object} is a {@link Network} that has the same elements and the
   * same structural relationships as those in this network.
   *
   * <p>Thus, two networks A and B are equal if <b>all</b> of the following are true:
   *
   * <ul>

  /**
   * This test will fail whenever someone updates/reorders the BloomFilterStrategies constants. Only
   * appending a new constant is allowed.
   */
  // This test ensures that our reliance on the ordering elsewhere is safe.
  @SuppressWarnings("EnumOrdinal")
  public void testBloomFilterStrategies() {
    assertThat(BloomFilterStrategies.values()).hasLength(2);

   * number of elements and whose elements may change over time.
   *
   * <p>This test might fail in GWT because the GWT emulations might count on the input collection
   * not to change during the copy. It is safe to do so in GWT because javascript is
   * single-threaded.
   */
  @GwtIncompatible // GWT is single threaded
  public void testCopyOf_threadSafe() {
    /*

 *       appropriate factory method for details. View collections such as {@link
 *       ImmutableMultiset#elementSet} iterate in the same order as the parent, except as noted.
 *   <li><b>Thread safety.</b> It is safe to access this collection concurrently from multiple
 *       threads.
 *   <li><b>Integrity.</b> This type cannot be subclassed outside this package (which would allow

   * unimplemented. So instead we use a dynamic proxy to get an implementation. If the method being
   * called on the {@code TypeVariable} instance has the same name as one of the public methods of
   * {@link TypeVariableImpl}, the proxy calls the same method on its instance of {@code
   * TypeVariableImpl}. Otherwise it throws {@link UnsupportedOperationException}; this should only

     */
    Throwable failureCause() {
      checkState(
          state == FAILED,
          "failureCause() is only valid if the service has failed, service is %s",
          state);
      // requireNonNull is safe because the constructor requires a non-null cause with state=FAILED.
      return requireNonNull(failure);
    }
  }

   *
   * @param valueClass class of values stored in the returned array
   */
  @GwtIncompatible // reflection
  public @Nullable V[][] toArray(Class<V> valueClass) {
    @SuppressWarnings("unchecked") // TODO: safe?
    @Nullable V[][] copy =
        (@Nullable V[][]) Array.newInstance(valueClass, rowList.size(), columnList.size());
    for (int i = 0; i < rowList.size(); i++) {
      arraycopy(array[i], 0, copy[i], 0, array[i].length);