code: private static int getIndexOfPair(String value, Map<Integer, String> row_data) {
          for(Integer i : row_data.keySet()) {
              if(row_data.get(i).equals(value)) {
                  return i.intValue();
              }
          } 
          return -1;
      }
docs: returns the index of the String in the HashMap, or -1 if value was not found.