public static User userLogin(String userName){
//获取数据库连接对象
Connection connection = DBManager.getConnection();
PreparedStatement preparedStatement = null;
ResultSet resultSet = null;
//生成SQL代码
StringBuilder sqlStatement = new StringBuilder();
sqlStatement.append("select * from user where Username=?");
try {
//设置数据库的字段值
preparedStatement = connection.prepareStatement(sqlStatement.toString());
preparedStatement.setString(1, userName);
resultSet = preparedStatement.executeQuery();
User user = new User();
if(resultSet.next()){
user.setUsername(resultSet.getString("Username"));
user.setPassword(resultSet.getString("Password"));
return user;
}
else{
return null;
}
} catch (SQLException ex) {
Logger.getLogger(UserDAO.class.getName()).log(Level.SEVERE, null, ex);
return null;
}finally{
DBManager.CloseAll(connection, preparedStatement, resultSet);
}
}