注册登录判断---后台代码（1）

本人现阶段是个学生，写代码没有什么经验，都是通过感觉写的，请各位大神指出错误所在，谢谢

后台代码：

思路：将前端文本框的用户名和密码，以参数传到后台Action中，之后进行查询，如果查询到的结果为0，则用户不存在，否则存在，之后在把返回值0 和 1通过Ajax接收，进行判断

Action

package net.xx.controller;

import java.io.IOException;
import java.io.PrintWriter;
import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;

import org.apache.struts2.ServletActionContext;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Scope;
import org.springframework.stereotype.Controller;

import com.opensymphony.xwork2.Action;

import net.xx.domain.Usert;
import net.xx.service.IUserService;

@Controller
@Scope("prototype")
public class LoginAction {
    @Autowired
    private IUserService userService;
    private Object data4;
    private Usert usert; 
    private String username;
    private String password;
     
    
    public String getUsername() {
        return username;
    }
    public void setUsername(String username) {
        this.username = username;
    }
     
    public Object getData4() {
        return data4;
    }
    public void setData4(Object data4) {
        this.data4 = data4;
    }
    public Usert getUsert() {
        return usert;
    }
    public void setUsert(Usert usert) {
        this.usert = usert;
    }
    
    public String getPassword() {
        return password;
    }
    public void setPassword(String password) {
        this.password = password;
    }
    public String execute(){
        boolean flag = userService.findUser(usert);
        if(flag){
            return Action.SUCCESS;
        }else{
            return Action.INPUT;
        }
    }
    public String check() throws IOException{
        username = URLDecoder.decode(username, "UTF-8");
        password = URLDecoder.decode(password, "UTF-8");
        data4 = userService.checkUser(username,password).size();
        int i = (int) data4;
        String result = "";
        if(i == 0){
            //用户不存在
            result = "0";
        }else{
            result = "1";
        }
         PrintWriter out =  ServletActionContext.getResponse().getWriter();
         out.write(result.toString());     
        return Action.SUCCESS;
    }
    
    
}

Dao接口

package net.xx.dao;

import java.util.List;

import net.xx.domain.Usert;

public interface IUserDao {
  //声明增加和查找方法
    public void saveUser(Usert user);
    public Usert findUser(Usert user);
    public List<Usert> getUser();
    public List<Usert> getUserByUsername(String username);
    public List<Usert> check(String username,String password);
    public List<Usert> checkPassword(String username);
}

Dao实现类

package net.xx.dao;

import java.util.List;

import org.hibernate.SessionFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Repository;

import net.xx.domain.Usert;
@Repository
public class UserDaoImpl implements IUserDao{
     @Autowired
     private SessionFactory sessionfactory;
    @Override
    public void saveUser(Usert user) {
        // TODO Auto-generated method stub
        sessionfactory.getCurrentSession().save(user);
    }

    @Override
    public Usert findUser(Usert user) {
        // TODO Auto-generated method stub
        Usert firstuser = new Usert();
        String hql = "from User user where user.username='"+user.getUsername()+"'and user.password'"+user.getPassword()+"'";
        //将查询结果放到List
        List<Usert> userlist = (List<Usert>) sessionfactory.getCurrentSession().createQuery(hql);
        if(userlist.size()>0){
            firstuser = userlist.get(0);
        }
        
        return firstuser;
    }
    //遍历数据库中的数据
    @Override
    public List<Usert> getUser() {
        // TODO Auto-generated method stub
        String hql="from Usert";
        List<Usert> users = sessionfactory.getCurrentSession().createQuery(hql).list();
        return users;
    }

    @Override
    public List<Usert> getUserByUsername(String username) {
        // TODO Auto-generated method stub
        String hql= "select * from Usert where username='"+username+"'";
        //通过输入的参数，得到用户的信息
        List<Usert> users =  (List<Usert>) sessionfactory.getCurrentSession().createSQLQuery(hql).list();
        return users; 
    }

    @Override
    public List<Usert> check(String username,String password) {
        // TODO Auto-generated method stub
        String hql = "select * from Usert where username='"+username+"' and password='"+password+"'";
        List<Usert> users = sessionfactory.getCurrentSession().createSQLQuery(hql).list();
        return users;
    }

    @Override
    public List<Usert> checkPassword(String username) {
        // TODO Auto-generated method stub
        String hql = "select password from Usert where username ='"+username+"'";
        List<Usert> password = sessionfactory.getCurrentSession().createSQLQuery(hql).list();
        
        return password;
    }
}

Service接口

package net.xx.service;

import java.util.List;

import net.xx.domain.Usert;

public interface IUserService {
   public void saveUser(Usert user);
   public boolean findUser(Usert user);
   List list();
   public List getUserByUsername(String username);
   List checkUser(String username,String password);
}

Service实现类

package net.xx.service;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import net.xx.dao.IUserDao;
import net.xx.domain.Usert;
@Service
public class UserServiceImpl implements IUserService{
     @Autowired
     private IUserDao userDao;
    @Override
    public void saveUser(Usert user) {
        // TODO Auto-generated method stub
        userDao.saveUser(user);
    }
    @Override
    public boolean findUser(Usert user) {
        // TODO Auto-generated method stub
        Usert firstuser = userDao.findUser(user);
        if(firstuser.getUsername()!=null){
            return true; 
        }else{
            return false;
        }         
    }

    @Override
    public List list() {
        // TODO Auto-generated method stub
        List<Usert> users = userDao.getUser();
        return users;
    }

    @Override
    public List getUserByUsername(String username) {
        // TODO Auto-generated method stub
        List<Usert> users =userDao.getUserByUsername(username);
        return users;
    }

    @Override
    public List checkUser(String username,String password) {
        // TODO Auto-generated method stub
        List<Usert> users = userDao.check(username,password);
        return users;
    }     
}