BookStore/src/com/yj/service/impl/UserServiceImpl.java

package com.yj.service.impl;

import com.yj.bean.Book;
import com.yj.bean.Page;
import com.yj.bean.User;
import com.yj.dao.UserDao;
import com.yj.dao.impl.UserDaoImpl;
import com.yj.service.UserService;

import java.util.List;

/**
 * @author yj
 * @create 2020-08-21 15:34
 */
public class UserServiceImpl implements UserService {

    private UserDao userDao = new UserDaoImpl();

    @Override
    public void registUser(User user) {
        userDao.saveUser(user);
    }

    @Override
    public User login(User user) {
        return userDao.querybyUsernameAndPassword(user.getUsername(),user.getPassword());
    }

    @Override
    public boolean existsUsername(String username) {
        if (userDao.querybyUsername(username) == null) {
            return false;
        } else {
            return true;
        }
    }

    @Override
    public void addUser(User user) {
        userDao.addUser(user);
    }

    @Override
    public void deleteUserById(int i) {
        userDao.deleteUserById(i);
    }

    @Override
    public void updateUser(User user) {
        userDao.updateUser(user);
    }

    @Override
    public User queryUserById(Integer id) {
        return userDao.queryUserById(id);
    }

    @Override
    public List<User> queryUsers() {
        return userDao.queryUsers();
    }

    @Override
    public Page<User> page(int pageNo, int pageSize) {
        Page<User> page = new Page<User>();

        //设置每页记录数
        page.setPageSize(pageSize);

        //设置总记录数
        Integer pageTotalCount = userDao.queryForPageTotalCount();
        page.setPageTotalCount(pageTotalCount);

        //求总页码
        Integer pageTotal = pageTotalCount / pageSize;
        if(pageTotalCount % pageSize >0) {
            pageTotal+=1;
        }
        //设置当前页
        if(pageNo>pageTotal) {
            pageNo = pageTotal;
        }
        if(pageNo<1) {
            pageNo = 1;
        }
        page.setPageNo(pageNo);
        //设置总页码
        page.setPageTotal(pageTotal);


        int begin = (page.getPageNo() -1)*pageSize;
        List<User> items = userDao.queryForPageItems(begin,pageSize);
        page.setItems(items);

        return page;
    }
}