163-javaweb简单登录与退出

java简单登录与退出


我们先写Service

public class UserService{

public User login(User form){

//查询username,得到user对象
User user =userDao.findByUsername(form.getUsername());

//如果用户不存在,抛出异常
if(user==null) throw new UserException("用户名不存在");
  
return user;
}



//然后写loing登录方法
public String login(HttpServletRequest request,
		HttpServletResponse response)
		throws ServletException,IOException{
	
	//封装表单数据到form中
	User form=CommonUtils.toBean(request.getParameterMap(),User.class);

	//调用userService的login方法
	try{
	
	User user=userService.login(form);

	//把user保存到session中
	request.getSession().setAttribute("session_user",user);
	
	return "f:/index.jsp";

	}catch(UserException e){
	request.setAttribute("msg",e.getMessage());
	request.setAttribute("form",form);
	return "f:/user/login.jsp";
	}
}

}




public String quit(HttpServletRequest request,
		HttpServletResponse response)
		throws ServletException,IOException{
	request.getSession().invalidate();
	return "f:/index.jsp";
}