public static String validateColumnName(@Nullable String columnName) {
    String name = requireNonNull(columnName, "Column name cannot be null");
    checkDbIdentifierCharacters(columnName, "Column name");
    return name;
  }
@Test
  public void fail_with_NPE_if_name_is_null() {
    assertThatThrownBy(() -> validateColumnName(null))
      .isInstanceOf(NullPointerException.class)
      .hasMessage("Column name cannot be null");
  }