code: public static String validateColumnName(@Nullable String columnName) {
      String name = requireNonNull(columnName, "Column name cannot be null");
      checkDbIdentifierCharacters(columnName, "Column name");
      return name;
    }
docs: Ensure {@code columnName} is a valid name for a column.
  @throws NullPointerException if {@code columnName} is {@code null}
  @throws IllegalArgumentException if {@code columnName} is not valid
  @return the same {@code columnName}
  @see #checkDbIdentifier(String, String, int)