* MoreObjects.toStringHelper(this)
   *     .omitNullValues()
   *     .add("x", 1)
   *     .add("y", null)
   *     .toString();
   * }</pre>
   *
   * <p>Note that in GWT, class names are often obfuscated.
   *
   * @param self the object to generate the string for (typically {@code this}), used only for its
   *     class name
   * @since 18.0 (since 2.0 as {@code Objects.toStringHelper()}).
   */

        "Logon failure: user not allowed to log on to this computer.",
        "Logon failure: the specified account password has expired.",
        "Logon failure: account currently disabled.",
        "No mapping between account names and security IDs was done.",
        "The security ID structure is invalid.",
        "All pipe instances are busy.",
        "All pipe instances are busy.",
        "The pipe state is invalid.",

 *       Synchronization policy</a>
 *   <li><a href="https://github.com/google/guava/wiki/GraphsExplained#notes-for-implementors">Notes
 *       for implementors</a>
 * </ul>
 *
 * @author James Sexton
 * @author Joshua O'Madadhain
 * @param <N> Node parameter type
 * @since 20.0
 */
@Beta
@DoNotMock("Use GraphBuilder to create a real instance")
@ElementTypesAreNonnullByDefault

  /**
   * Null ('\0'): The all-zeros character which may serve to accomplish time fill and media fill.
   * Normally used as a C string terminator.
   *
   * <p>Although RFC 20 names this as "Null", note that it is distinct from the C/C++ "NULL"
   * pointer.
   *
   * @since 8.0
   */
  public static final byte NUL = 0;

  /**

 *       Synchronization policy</a>
 *   <li><a href="https://github.com/google/guava/wiki/GraphsExplained#notes-for-implementors">Notes
 *       for implementors</a>
 * </ul>
 *
 * @author James Sexton
 * @author Joshua O'Madadhain
 * @param <N> Node parameter type
 * @param <E> Edge parameter type
 * @since 20.0
 */
@Beta
@DoNotMock("Use NetworkBuilder to create a real instance")

  /* The names of the expected method that tests null checks. */
  private static final ImmutableList<String> NULL_TEST_METHOD_NAMES =
      ImmutableList.of(
          "testNulls", "testNull",
          "testNullPointers", "testNullPointer",
          "testNullPointerExceptions", "testNullPointerException");

  /* The names of the expected method that tests serializable. */

                Path subdir = test;
                if (isModuleHierarchy) {
                    // If module hierarchy is used, the directory names shall be the module names.
                    Path path = test.resolve(moduleName);
                    if (!Files.isDirectory(path)) {
                        // Main module without tests. It is okay.
                        continue;

  }

  static boolean isPrimitiveOrNullable(Parameter param) {
    return param.getType().getRawType().isPrimitive() || isNullable(param);
  }

  private static final ImmutableSet<String> NULLABLE_ANNOTATION_SIMPLE_NAMES =
      ImmutableSet.of("CheckForNull", "Nullable", "NullableDecl", "NullableType");

  static boolean isNullable(Invokable<?, ?> invokable) {
    return NULLNESS_ANNOTATION_READER.isNullable(invokable);
  }

   * Foundation's <a href="http://publicsuffix.org/">Public Suffix List</a> (PSL). A public suffix
   * is one under which Internet users can directly register names, such as {@code com}, {@code
   * co.uk} or {@code pvt.k12.wy.us}. Examples of domain names that are <i>not</i> public suffixes
   * include {@code google.com}, {@code foo.co.uk}, and {@code myblog.blogspot.com}.
   *

 * this class rather than implement {@link Network} directly.
 *
 * <p>The methods implemented in this class should not be overridden unless the subclass admits a
 * more efficient implementation.
 *
 * @author James Sexton
 * @param <N> Node parameter type
 * @param <E> Edge parameter type
 * @since 20.0
 */
@Beta
@ElementTypesAreNonnullByDefault
public abstract class AbstractNetwork<N, E> implements Network<N, E> {