code: public int getIdentifierMaximumLength() {
          try {
              if (getDatabaseMajorVersion() < ORACLE_12C_MAJOR_VERSION) {
                  return SHORT_IDENTIFIERS_LENGTH;
              }
              else if ((getDatabaseMajorVersion() == ORACLE_12C_MAJOR_VERSION) && (getDatabaseMinorVersion() <= 1)) {
                  return SHORT_IDENTIFIERS_LENGTH;
              } else {
                  return LONG_IDENTIFIERS_LEGNTH;
              }
          } catch (DatabaseException ex) {
              throw new UnexpectedLiquibaseException("Cannot determine the Oracle database version number", ex);
          }
  
      }
docs: Returns the maximum number of bytes (NOT: characters) for an identifier. For Oracle <=12c Release 20, this
  is 30 bytes, and starting from 12cR2, up to 128 (except for tablespaces, PDB names and some other rather rare
  object types).
  @return the maximum length of an object identifier, in bytes