static final String ERROR_ELEMENT_REMOVED = "used to generate this set";
  private static final String NODE_STRING = "Node";
  private static final String EDGE_STRING = "Edge";

  enum EdgeType {
    UNDIRECTED,
    DIRECTED;
  }

  private TestUtil() {}

  static void assertNodeNotInGraphErrorMessage(Throwable throwable) {
    assertThat(throwable).hasMessageThat().startsWith(NODE_STRING);

    /**
     * Handles the prologue phase of action execution.
     * <p>
     * This method catches UserRoleLoginException and redirects to the
     * appropriate action class.
     * </p>
     *
     * @param runtime the action runtime context
     * @return the action response, or redirect response if login exception occurs
     */
    @Override
    public ActionResponse godHandPrologue(final ActionRuntime runtime) {

    }

    /**
     * Redirects the user to the root path of the application.
     *
     * @return HTML response that redirects to the root page
     */
    protected HtmlResponse redirectToRoot() {
        return systemHelper.getRedirectResponseToRoot(newHtmlResponseAsRedirect("/"));
    }

    /**

 * currently carrying zero streams is an idle stream. We keep it alive because reusing an existing
 * connection is typically faster than establishing a new one.
 *
 * When a single logical call requires multiple streams due to redirects or authorization
 * challenges, we prefer to use the same physical connection for all streams in the sequence. There
 * are potential performance and behavior consequences to this preference. To support this feature,

    when certificates matched but the DNS addresses did not. This would only occur when following a
    redirect from one hostname to another, and where both hosts had common certificates.

 *  Fix: Don't fail on a redirect when a client has configured a 'trust everything' trust manager.
    Typically this would cause certain redirects to fail in debug and development configurations.


## Version 4.4.0

_2020-02-17_

 *   <li>Starting and finishing threads</li>
 *   <li>Starting and cleaning up crawling</li>
 *   <li>Handling unsupported URLs</li>
 *   <li>Checking last modified dates</li>
 *   <li>Getting content</li>
 *   <li>Handling redirects</li>
 *   <li>Processing responses</li>
 *   <li>Handling exceptions during crawling and child URL processing</li>
 *   <li>Handling cases where no URL is in the queue</li>

    Graph<?> other = (Graph<?>) obj;

    return isDirected() == other.isDirected()
        && nodes().equals(other.nodes())
        && edges().equals(other.edges());
  }

  @Override
  public final int hashCode() {
    return edges().hashCode();
  }

  /** Returns a string representation of this graph. */
  @Override
  public String toString() {
    return "isDirected: "
        + isDirected()

    return endpoints.isOrdered() == this.isDirected();
  }

  @Override
  public final boolean equals(@Nullable Object obj) {
    if (obj == this) {
      return true;
    }
    if (!(obj instanceof Network)) {
      return false;
    }
    Network<?, ?> other = (Network<?, ?>) obj;

    return isDirected() == other.isDirected()
        && nodes().equals(other.nodes())

      }

      @Override
      public Set<EndpointPair<N>> edges() {
        return AbstractValueGraph.this.edges();
      }

      @Override
      public boolean isDirected() {
        return AbstractValueGraph.this.isDirected();
      }

      @Override
      public boolean allowsSelfLoops() {
        return AbstractValueGraph.this.allowsSelfLoops();
      }

      @Override

    return endpoints.isOrdered() == this.isDirected();
  }

  @Override
  public final boolean equals(@Nullable Object obj) {
    if (obj == this) {
      return true;
    }
    if (!(obj instanceof Network)) {
      return false;
    }
    Network<?, ?> other = (Network<?, ?>) obj;

    return isDirected() == other.isDirected()
        && nodes().equals(other.nodes())