code: public static final Parser<Long> instance() { // NOPMD it's thread save!
      if (LongParserWithoutSeparator.instanceParser == null) {
        synchronized (LongParserWithoutSeparator.class) {
          if (LongParserWithoutSeparator.instanceParser == null) {
            LongParserWithoutSeparator.instanceParser = new LongParserWithoutSeparator();
          }
        }
      }
      return LongParserWithoutSeparator.instanceParser;
    }
docs: returns the instance.
  
  @return IntegerParserWithoutSeparator