code: public void setInterchangeLevel(int level) throws ConfigException {
          if (level < 1 || level > 3) {
              throw new ConfigException(this, "Invalid ISO9660 Interchange Level: " + level);
          }
          if (level == 3) {
              throw new ConfigException(this,
                      "Interchange Level 3 (multiple File Sections per file) is not (yet) supported by this implementation.");
          }
          ISO9660NamingConventions.INTERCHANGE_LEVEL = level;
      }
docs: Set Interchange Level<br> 1: Filenames 8+3, directories 8 characters<br> 2: Filenames 30, directories 31
  characters<br> 3: multiple File Sections (files > 2 GB)
  
  @param level 1, 2 or 3
  
  @throws com.github.stephenc.javaisotools.iso9660.ConfigException Invalid or unsupported Interchange Level