```java public Student get(){ Student stu = null; //获取连接 Connection conn = DbUtil.getConnection(); //sql, 每行加空格 String sql = "select * from student where id=?"; //预编译SQL，减少sql执行 PreparedStatement ptmt = conn.prepareStatement(sql); //传参 ptmt.setInt(1, id); //执行 ResultSet rs = ptmt.executeQuery(); while(rs.next()){ stu = new Student(); stu.setId(rs.getInt("id")); stu.setUser_name(rs.getString("user_name")); stu.setAge(rs.getInt("age")); stu.setSex(rs.getInt("sex")); stu.setBirthday(rs.getString("birthday")); stu.setEmail(rs.getString("email")); } DbUtil.close(ptmt,conn); return stu; } ```