code: public static String clobToStr(Clob clob) {
  		Reader reader = null;
  		try {
  			reader = clob.getCharacterStream();
  			return IoUtil.read(reader);
  		} catch (SQLException e) {
  			throw new DbRuntimeException(e);
  		} finally {
  			IoUtil.close(reader);
  		}
  	}
docs: Clob字段值转字符串
  
  @param clob {@link Clob}
  @return 字符串
  @since 3.0.6