docs: public static final int fillDateTimePool(IWord[] wPool, IWord word)
      {
          int pIdx = getDateTimeIndex(word.getEntity(0));
          if ( pIdx == DATETIME_NONE ) {
              return DATETIME_NONE;
          }
          
          if ( wPool[pIdx] == null ) {
              wPool[pIdx] = word;
              return pIdx;
          }
          
          return DATETIME_NONE;
      }