oracle中返回主键值

在今天的ATM中，就用纯粹的jdbc来处理数据，当发现用user ，card，log之间的关系，在save用户之后，要用到user中id来关联到card中，的字段，而oracle中插入和跟新之后是返回的插入和更新的行数，后来想了想，也上网搜了一些资料，现在总结如下，

/**      * 添加用户      */     @Override     public int save(User user)     {         temp = -1;         final String sql = "insert into atm_user(username,password,sex,idCard) values(?,?,?,?)";

        try         {            String key[] =             { "id" };             ps = this.conn.prepareStatement(sql, key);             ps.setString(1, user.getUsername());             ps.setString(2, user.getPassword());             ps.setString(3, String.valueOf(user.getSex()));             ps.setString(4, user.getIdCard());             temp = ps.executeUpdate();             System.out.println(temp);

            rs = ps.getGeneratedKeys();             rs.next();             if (temp > 0)             {                 temp = Integer.valueOf(rs.getString(1));             }

        } catch (SQLException e)         {             e.printStackTrace();             try             {                 conn.rollback();             } catch (SQLException e1)             {                 e1.printStackTrace();             }         } finally         {             close();         }         return temp;     }