@Override
  public int hashCode() {
    int result = startOffset;
    result = 31 * result + (cssClass != null ? cssClass.hashCode() : 0);
    return result;
  }
@Test
  public void test_hashcode() {
    OpeningHtmlTag openingHtmlTag = new OpeningHtmlTag(3, "tag");
    OpeningHtmlTag openingHtmlTagWithSameValues = new OpeningHtmlTag(3, "tag");
    OpeningHtmlTag openingHtmlTagWithDifferentValue = new OpeningHtmlTag(5, "tag2");

    assertThat(openingHtmlTag)
      .hasSameHashCodeAs(openingHtmlTagWithSameValues)
      .hasSameHashCodeAs(openingHtmlTag);
    assertThat(openingHtmlTag.hashCode()).isNotEqualTo(openingHtmlTagWithDifferentValue.hashCode());
  }