ImmutableSortedSet.Builder<String> builder = ImmutableSortedSet.orderedBy(comparator);
      builder.add(BEFORE_FIRST);
      builder.add(BEFORE_FIRST_2);
      builder.add(elements);
      builder.add(AFTER_LAST);
      builder.add(AFTER_LAST_2);
      return builder
          .build()
          .subSet(BEFORE_FIRST_2, AFTER_LAST_2)
          .asList()

  }

  @ListFeature.Require(SUPPORTS_ADD_WITH_INDEX)
  public void testAddAtIndex_negative() {
    assertThrows(IndexOutOfBoundsException.class, () -> getList().add(-1, e3()));
    expectUnchanged();
    expectMissing(e3());
  }

  @ListFeature.Require(SUPPORTS_ADD_WITH_INDEX)
  public void testAddAtIndex_tooLarge() {

        // pvno [0] INTEGER 5
        v.add(new DERTaggedObject(true, 0, new ASN1Integer(Integer.parseInt(KerberosConstants.KERBEROS_VERSION))));
        // msg-type [1] INTEGER 14 (AP-REQ)
        v.add(new DERTaggedObject(true, 1, new ASN1Integer(Integer.parseInt(KerberosConstants.KERBEROS_AP_REQ))));
        // ap-options [2] BIT STRING

        originalPairs.add(new AvFlags(0x12345678));
        originalPairs.add(new AvTimestamp(new byte[] { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08 }));
        originalPairs.add(new AvTargetName("TESTNAME".getBytes()));
        originalPairs.add(new AvSingleHost(new byte[] { 0x11, 0x22, 0x33, 0x44 }));
        originalPairs.add(new AvChannelBindings(new byte[] { 0x55, 0x66 }));

    List<Class<? extends AbstractTester>> testers = copyToList(super.getTesters());

    testers.add(CollectionSerializationEqualTester.class);
    testers.add(SetAddAllTester.class);
    testers.add(SetAddTester.class);
    testers.add(SetCreationTester.class);
    testers.add(SetHashCodeTester.class);
    testers.add(SetEqualsTester.class);
    testers.add(SetRemoveTester.class);
    // SetRemoveAllTester doesn't exist because, Sets not permitting

    }

    // Test add method with null engine
    public void test_add_nullEngine() {
        try {
            scriptEngineFactory.add("test", null);
            fail("Should throw IllegalArgumentException for null engine");
        } catch (IllegalArgumentException e) {
            assertEquals("name or scriptEngine is null.", e.getMessage());
        }
    }

    // Test add method with both null parameters

    /**
     * Add the created action message for the key 'errors.front_header' with parameters.
     * <pre>
     * message:
     * </pre>
     * @param property The property name for the message. (NotNull)
     * @return this. (NotNull)
     */
    public FessMessages addErrorsFrontHeader(String property) {
        assertPropertyNotNull(property);
        add(property, new UserMessage(ERRORS_front_header));

      ImmutableSortedSet.Builder<String> builder = ImmutableSortedSet.orderedBy(comparator);
      builder.add(BEFORE_FIRST);
      builder.add(BEFORE_FIRST_2);
      builder.add(elements);
      builder.add(AFTER_LAST);
      builder.add(AFTER_LAST_2);
      return builder
          .build()
          .subSet(BEFORE_FIRST_2, AFTER_LAST_2)
          .asList()

    }

    public void test_load_virtualHosts() {
        List<RelatedQuery> testData = new ArrayList<>();
        testData.add(createRelatedQuery("term1", new String[] { "query1" }, "host1"));
        testData.add(createRelatedQuery("term1", new String[] { "query2" }, "host2"));
        testData.add(createRelatedQuery("term2", new String[] { "query3" }, ""));
        mockBhv.setTestData(testData);

        fieldSet.add("cluster_name");
        fieldSet.add("status");
        fieldSet.add("timed_out");
        fieldSet.add("number_of_nodes");
        fieldSet.add("number_of_data_nodes");
        fieldSet.add("active_primary_shards");
        fieldSet.add("active_shards");
        fieldSet.add("relocating_shards");
        fieldSet.add("initializing_shards");