private boolean actualSymbolNotProcessed(String roman, SymbolValue symbolValue) {
   return roman.indexOf(symbolValue.getSymbol(), index) == index;
 }
 private void process(String roman, SymbolValue symbolValue) {
   while (actualSymbolNotProcessed(roman, symbolValue)) {
     arabic += symbolValue.getValue();
     index += symbolValue.getSymbol().length();
   }
 }