利用GeneratedKeyHolder获得新建数据主键值

Posted 2020-08-11

Spring利用GeneratedKeyHolder，提供了一个可以返回新增记录对应主键值的方法：int update(PreparedStatementCreator psc, KeyHolder generatedKeyHolder).

Spring为KeyHolder接口指代了一个通用的实现类GeneratedKeyHolder，该类返回新增记录时的自增长主键值。假设我们希望在新增论坛板块对象后，希望将主键值加载到对象中，则可以按以下代码进行调整：

 1 final String INSERT_SQL = "insert into gtable(username,callback) values(?,?)";
 2         KeyHolder keyHolder = new GeneratedKeyHolder();
 3         jdbcTemplate.update(new PreparedStatementCreator() {
 4             public PreparedStatement createPreparedStatement(
 5                     Connection connection) throws SQLException {
 6                 PreparedStatement ps = connection.prepareStatement(INSERT_SQL,
 7                         new String[] { "id" });
 8                 ps.setString(1, request.getUsername());
 9                 ps.setString(2, request.getCallback());
10                 return ps;
11             }
12         }, keyHolder);
13 logger.debug("id:" + keyHolder.getKey()+"long:"+keyHolder.getKey().longValue());