基于jsp和mysql实现的学生选课管理系统

package dao; import bean.User; import java.sql.Date; import java.sql.ResultSet; import java.sql.SQLException; import java.util.ArrayList; import java.util.Calendar; import java.util.List; public class UserDao { public User login(String username, String password) throws SQLException { // 定义sql语句 String sql = "select * from user where username = ? and password = ?"; Object[] obj = {username,password}; //执行sql语句,执行完后，有记录，说明账号密码输入正确 ResultSet rs = JdbcBase.querySql(sql,obj); // rs.next() 判断有没有下一条记录 User user = null; if(rs.next()){ user = new User(); user.setUsername(rs.getString("username")); user.setPassword(rs.getString("password")); } return user; } public int addClass(String username,String password,String name,String sex,int age,int type,String course){ String sql = "insert into user(username,password,name,sex,age,type,course) value(?,?,?,?,?,?,?)"; Object[] obj = {username,password,name,sex,age,type,course}; int num = JdbcBase.updateSql(sql,obj); return num; } public List<User> selectAllStaff() throws SQLException { // 定义查询的sql语句 String sql = "select * from user where type = 2"; Object[] obj = {}; List<User> list = new ArrayList<User>(); ResultSet rs = JdbcBase.querySql(sql,obj); while(rs.next()){ User user = new User(); user.setUsername(rs.getString("username")); user.setPassword(rs.getString("password")); user.setName(rs.getString("name")); user.setSex(rs.getString("sex")); user.setAge(rs.getInt("age")); user.setType(rs.getInt("type")); user.setCourse(rs.getString("course")); list.add(user); } return list; } // 年龄格式化方法： //利用出生日期获得年龄 /* private int getAge(Date birth){ //获取日历 Calendar cal = Calendar.getInstance(); int thisYear = cal.get(Calendar.YEAR); int thisMonth = cal.get(Calendar.MONTH); int dayOfMonth = cal.get(Calendar.DAY_OF_MONTH); cal.setTime(birth); int birthYear = cal.get(Calendar.YEAR); int birthMonth = cal.get(Calendar.MONTH); int birthdayOfMonth = cal.get(Calendar.DAY_OF_MONTH); int age = thisYear - birthYear; // 未足月 if (thisMonth <= birthMonth) { // 当月 if (thisMonth == birthMonth) { // 未足日 if (dayOfMonth < birthdayOfMonth) { age--; } } else { age--; } } return age; } */ }