}
public boolean userLogin(HttpServletRequest request, String userName, String password)throws Exception
{
if(userName==null || password == null)
throw new LoginException();
String cryptPassword = DigestUtils.sha256Hex(password +passwordHashPadding);
User user = new User();
List<User> userList=userDAO.selectUser(userName,cryptPassword);
if(userList.size()==0)
throw new LoginException();
for(int i=0;i<userList.size();i++)
{
user = userList.get(i);
}
request.getSession().setAttribute("userName", user.getUserName());