code: @Override
      public final Class<J> jdbcClass() {
          @SuppressWarnings("unchecked")
          Class<J> result = (Class<J>) TypeHelper.getTypeArguments(ColumnMapper.class, getClass()).get(1);
          return result;
      }
docs: /* (non-Javadoc)
  @see org.jadira.usertype.dateandtime.shared.spi.ColumnMapper#jdbcClass()