jsp用户管理访问数据库

Jsp用户管理连接数据库

三种方法在src包下创建user包创建UserDao类7jsp1D:\jspuse\jsp1idea■outv■src十corri.binhdivBclbcDEConnectionwnlogincHelloServletcLoginSerdetcTestserdetvEluseicUserDaohtestpackagecom.binhai.user;importcom.binhai.db.DBConnection;importjava.sql.*;importstaticcom.binhai.db.DBConnection.getConnection;〃用户管理访问数据库publicclassUserDao(//登录publicbooleanlogin(Stringusername,Stringpassword)throwsSQLException(〃连接数据库Connectionconnection=DBConnection.getConnection();//(l)statment方法//statment不能接收参数/*Statementstatement=connection.createStatement();〃执行SQL语句Stringsql="select*fromt_userwhereusername=?andpassword=?";ResultSetresultSet=statement.executeQuery(sql);*///(2)PreparedStatement方法——最常用//防止SQL注入攻击，提高代码可读性、可维护性，提高效率PreparedStatement preparedStatement=connection.prepareStatement("select");//使用preparedStatement的setXxx方法设置每一个位置上的值preparedStatement.setString(1,username);preparedStatement.setString(2,password);ResultSetresultSet=preparedStatement.executeQuery();〃⑶CallableStatement方法----数据库需要有存储过程//访问存储过程，防止SQL注入攻击，提高效率/*CallableStatementcallableStatement=connection.prepareCall("{callselect_user(??)}");callableStatement.setString(1,username);callableStatement.setString(2,password);ResultSetresultSet二callableStatement.executeQuery();*/〃处理结果集try{if(resultSet.next()){

returntrue;}else{returnfalse;}catch