求大神注释一下这段代码是什么意思

Question

public int guahaoAdd(Connection con, GuaHao guahao)throws Exception{
String sql="insert into t_ghinfo values(null,?,?,?,?,?)";
PreparedStatement pstmt=con.prepareStatement(sql);
pstmt.setInt(1, guahao.getPatientId());
pstmt.setString(2, new java.text.SimpleDateFormat("yyyyMMddHHmmss").format(new java.util.Date()));
pstmt.setString(3, DateUtil.formatDate(guahao.getDate(), "yyyy-MM-dd"));
pstmt.setString(4, guahao.getOfficeName());
pstmt.setString(5, guahao.getGhDesc());
return pstmt.executeUpdate();
}

Answer 1

//定义要执行的sql语句
String sql="insert into t_ghinfo values(null,?,?,?,?,?)";

//从conn获取到PreparedStatement对象，用于执行数据库操作
PreparedStatement pstmt=con.prepareState，ment(sql);

//接下来的几行代码用于向sql语句中的几个？赋值
pstmt.setInt(1, guahao.getPatientId());
pstmt.setString(2, new java.text.SimpleDateFormat("yyyyMMddHHmmss").format(new java.util.Date()));
pstmt.setString(3, DateUtil.formatDate(guahao.getDate(), "yyyy-MM-dd"));
pstmt.setString(4, guahao.getOfficeName());
pstmt.setString(5, guahao.getGhDesc());

//执行上面的sql语句，返回值是本次操作数据库的影响行数
return pstmt.executeUpdate();