code: public void importFromMixed(Reader r, boolean deduceFromSeeds) {
          BufferedReader reader = new BufferedReader(r);
          String s;
          
          Iterator<String> iter = 
              new RegexLineIterator(
                      new LineReadingIterator(reader),
                      RegexLineIterator.COMMENT_LINE,
                      RegexLineIterator.NONWHITESPACE_ENTRY_TRAILING_COMMENT,
                      RegexLineIterator.ENTRY);
  
          while (iter.hasNext()) {
              s = (String) iter.next();
              if(s.startsWith(SURT_PREFIX_DIRECTIVE)) {
                  considerAsAddDirective(s.substring(SURT_PREFIX_DIRECTIVE.length()));
                  continue; 
              } else {
                  if(deduceFromSeeds) {
                      // also deducing 'implied' SURT prefixes 
                      // from normal URIs/hostname seeds
                      addFromPlain(s);
                  }
              }
          }
      }
docs: Import SURT prefixes from a reader with mixed URI and SURT prefix
  format.
  
  @param r  the reader to import the prefixes from
  @param deduceFromSeeds   true to also import SURT prefixes implied
  from normal URIs/hostname seeds