private static final Integer NODE_NOT_IN_GRAPH = 1000;
  private static final String E11 = "1-1";
  private static final String E11_A = "1-1a";
  private static final String E12 = "1-2";
  private static final String E12_A = "1-2a";
  private static final String E21 = "2-1";
  private static final String E23 = "2-3";

  @Parameters
  public static Collection<Object[]> parameters() {
    return Arrays.asList(
        new Object[][] {

  private static final Integer N2 = 2;
  private static final Integer N3 = 3;
  private static final Integer N4 = 4;
  private static final String E12 = "1-2";
  private static final String E12_A = "1-2a";
  private static final String E21 = "2-1";
  private static final String E13 = "1-3";
  private static final String E44 = "4-4";

  // Test for EndpointPair class

  @Test
  public void testOrderedEndpointPair() {