记一次向数据库添加记录并且获取自增id

DataSource ds = JDBCUtil.getDataSource();
        String sql = "INSERT INTO user(id, username, password) VALUES (NULL, "123", "123456");";
        Connection conn = null;
        PreparedStatement stat = null;
        try {
            conn = ds.getConnection();
            stat = conn.prepareStatement(sql, Statement.RETURN_GENERATED_KEYS);

            stat.executeUpdate();

            ResultSet rs = stat.getGeneratedKeys();
            while (rs.next()) {
                System.out.println(rs.getInt(1));
            }

        } catch (SQLException e) {
            e.printStackTrace();
        }finally {
            JDBCUtil.close(stat, conn);
        }