public static String cleanColumn(String column) {
        if (column == null) {
            return null;
        }
        if (column.contains("`")) {
            column = column.replaceAll("`", "");
        }

        if (column.contains("'")) {
            column = column.replaceAll("'", "");
        }

        if (column.contains("\"")) {
            column = column.replaceAll("\"", "");
        }

        return column;
    }
@Test
  public void cleanColumnInputNullOutputNull() {

    // Arrange
    final String column = null;

    // Act
    final String actual = Util.cleanColumn(column);

    // Assert result
    Assert.assertNull(actual);
  }