if (!columnIterator.hasNext()) {
        rowEntry = rowIterator.next();
        columnIterator = rowEntry.getValue().entrySet().iterator();
      }
      /*
       * requireNonNull is safe because:
       *
       * - columnIterator started off pointing to an empty iterator, so we must have entered the
       *   `if` body above at least once. Thus, if we got this far, that `if` body initialized

 * {@link #unmodifiableKeySet()}. By design, the cache is cleared when this structure is mutated. If
 * this structure is never mutated, it provides a thread-safe view of the backing map.
 *
 * <p>The {@link MapIteratorCache} assumes ownership of the backing map, and cannot guarantee
 * correctness in the face of external mutations to the backing map. As such, it is <b>strongly</b>

 * comparator is not consistent with {@code equals}.
 *
 * <p>The {@code standard} methods are not guaranteed to be thread-safe, even when all of the
 * methods that they depend on are thread-safe.
 *
 * @author Mike Bostock
 * @author Louis Wasserman
 * @since 2.0
 */
@GwtCompatible

   *     wrap(Integer.class) == Integer.class
   *     wrap(String.class) == String.class
   * </pre>
   */
  public static <T> Class<T> wrap(Class<T> type) {
    checkNotNull(type);

    // cast is safe: long.class and Long.class are both of type Class<Long>
    @SuppressWarnings("unchecked")
    Class<T> wrapped = (Class<T>) PRIMITIVE_TO_WRAPPER_TYPE.get(type);
    return (wrapped == null) ? type : wrapped;
  }

   */
  @SuppressWarnings("unchecked") // Safe as long as the javadocs are followed
  static <K, V> ImmutableMapEntry<K, V>[] createEntryArray(int size) {
    return (ImmutableMapEntry<K, V>[]) new ImmutableMapEntry<?, ?>[size];
  }

  ImmutableMapEntry(K key, V value) {
    super(key, value);
    checkEntryNotNull(key, value);
  }

  // Redeclare methods to make them `final`, just to be extra-safe.

  @Override
  @ParametricNullness

      if (!columnIterator.hasNext()) {
        rowEntry = rowIterator.next();
        columnIterator = rowEntry.getValue().entrySet().iterator();
      }
      /*
       * requireNonNull is safe because:
       *
       * - columnIterator started off pointing to an empty iterator, so we must have entered the
       *   `if` body above at least once. Thus, if we got this far, that `if` body initialized

    assertUnescaped(e, '~');
    assertUnescaped(e, ':');
    assertUnescaped(e, '@');

    // Don't use plus for spaces
    assertEscaping(e, "%20", ' ');

    assertThat(e.escape("safe with spaces")).isEqualTo("safe%20with%20spaces");
    assertThat(e.escape("******@****.***")).isEqualTo("******@****.***");
  }

  private UrlEscaperTesting() {}

        connections.removePredecessor(node);
        --edgeCount;
      }
    }

    for (N successor : ImmutableList.copyOf(connections.successors())) {
      // requireNonNull is safe because the node is a successor.
      requireNonNull(nodeConnections.getWithoutCaching(successor)).removePredecessor(node);
      requireNonNull(connections.removeSuccessor(successor));
      --edgeCount;
    }

    assertUnescaped(e, '~');
    assertUnescaped(e, ':');
    assertUnescaped(e, '@');

    // Don't use plus for spaces
    assertEscaping(e, "%20", ' ');

    assertThat(e.escape("safe with spaces")).isEqualTo("safe%20with%20spaces");
    assertThat(e.escape("******@****.***")).isEqualTo("******@****.***");
  }

  private UrlEscaperTesting() {}

   * Returns an immutable map containing the same entries as {@code map}, sorted by the natural
   * ordering of the keys.
   *
   * <p>Despite the method name, this method attempts to avoid actually copying the data when it is
   * safe to do so. The exact circumstances under which a copy will or will not be performed are
   * undocumented and subject to change.
   *