spring Jdbc自动获取主键。



spring 搭建底层框架，本来简单的save保存对象，可是需要返回主键，那么就用一下代码实现。

public Long createOrder(final  Order  order) throws Exception {

KeyHolder    keyHolder = new GeneratedKeyHolder();
try {
jdbcTemplate.update(new PreparedStatementCreator() {
@Override
public PreparedStatement createPreparedStatement(
Connection connection) throws SQLException {
//拼装插入数据库的sql
String sql = orderSql(order);

PreparedStatement ps = connection.prepareStatement(sql);
return ps;
}
}, keyHolder);
} catch (Exception e) {
e.printStackTrace();
return null;
}
return keyHolder.getKey().longValue();
}