blob下载出现多余乱码内容

blob需要单独获取，，不能通过map来获取

jdbcTemplate.query(sqlcontent, new Object[] {id},
     new AbstractLobStreamingResultSetExtractor<Object>() {
      @Override
      protected void streamData(ResultSet arg0)
        throws SQLException, IOException,
        DataAccessException {
       System.out.println("dksajd;sa;ldajd;sd");
       FileCopyUtils.copy(lobHandler.getBlobAsBinaryStream(arg0, 1),out);
       
      }
     });