基于JSP的学生考勤系统PreparedStatementpst=null;Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");if(con==null||con.isClosed()){con=DriverManager.getConnection("jdbc:sqlserver://localhost:1433;databaseName=kaoqin","sa","sa");}pst=con.prepareStatement(sql);returnpst;