com.jsj.dao.Impl====新闻发布系统（6）

是对dao层的实现

AdminDaoImpl

package com.jsj.dao.Impl;

import com.jsj.dao.AdminDao;
import com.jsj.entity.Admin;
import com.jsj.utils.BeanHandler;
import com.jsj.utils.JdbcTemplate;

public class AdminDaoImpl implements AdminDao {
    //实现上面对应的接口的方法
    //接收到username和password参数
    @Override
    public Admin getAdminByPassword(String username, String password) throws Exception {
       //sql语句，？可以看做是变量，你可以添加数据的
        String sql = "select * from admin where username = ? and password = ?";
        //然后调用工具类，（Admin)这是强制转换，
        //类名.方法名，是因为方法是static类型的，所以不要创建对象，然后在调用
        //query的参数有：sql语句，new BeanHandler(Admin.class)是对象、username、password
        //Admin.class是：返回的Adimin的Class对象，如果后面加newINnstace()就好创建对象
        return (Admin) JdbcTemplate.query(sql, new BeanHandler(Admin.class), username, password);
    }
}

NewCateDaoImpl

package com.jsj.dao.Impl;

import com.jsj.dao.NewsCateDao;
import com.jsj.entity.NewsCate;
import com.jsj.utils.BeanHandler;
import com.jsj.utils.BeanListHandler;
import com.jsj.utils.JdbcTemplate;

import java.util.List;

public class NewsCateDaoImpl implements NewsCateDao {

    @Override
    public List<NewsCate> getAll() throws Exception {
        //sql语句，实现查找
        String sql = "select * from news_cate";
        //就是直接调用工具类
        return (List<NewsCate>) JdbcTemplate.query(sql,new BeanListHandler(NewsCate.class));
    }

    @Override
    public NewsCate getById(Integer id) throws Exception {
        String sql = "select * from news_cate where id = ?";
        return (NewsCate) JdbcTemplate.query(sql, new BeanHandler(NewsCate.class),id);
    }

    @Override
    public int insert(NewsCate newsCate) throws Exception {
        String sql = "insert into news_cate(name) values (?)";
        return JdbcTemplate.update(sql, newsCate.getName());
    }

    @Override
    public int update(NewsCate newsCate) throws Exception {
        String sql = "update news_cate set name=? where id=?";
        return JdbcTemplate.update(sql, newsCate.getName(),newsCate.getId());
    }

    @Override
    public int deleteById(Integer id) throws Exception {
        String sql = "delete from news_cate where id = ?";
        return JdbcTemplate.update(sql, id);
    }
}

NewDaoImpl

package com.jsj.dao.Impl;

import com.jsj.dao.NewsDao;
import com.jsj.entity.News;
import com.jsj.utils.BeanHandler;
import com.jsj.utils.BeanListHandler;
import com.jsj.utils.JdbcTemplate;

import java.sql.*;
import java.util.List;

public class NewsDaoImpl implements NewsDao {

    @Override
    public int getCount() throws Exception {
        String sql = "select count(*) from news";
        return JdbcTemplate.queryCount(sql);
    }

    @Override
    public int getCountByCate(Integer cateId) throws Exception {
        String sql = "select count(*) from news where cate_id = ? order by time desc";
        return JdbcTemplate.queryCount(sql, cateId);
    }

    @Override
    public List<News> getNewsList(Integer beginIndex, Integer length) throws Exception {
        String sql = "select * from news order by time desc limit ?, ?";
        return (List<News>) JdbcTemplate.query(sql,new BeanListHandler(News.class),beginIndex, length);
    }

    @Override
    public List<News> getNewsListByCate(Integer cateId,Integer beginIndex,Integer length) throws Exception {
        String sql = "select * from news where cate_id = ? limit ?, ?";
        return (List<News>) JdbcTemplate.query(sql, new BeanListHandler(News.class),cateId,beginIndex, length);
    }

    @Override
    public int insert(News news) throws Exception {
        String sql = "insert into news(cate_id,title,author,time,content) values (?,?,?,?,?)";
        return JdbcTemplate.update(sql, news.getCateId(),news.getTitle(),news.getAuthor(),
                new Date(news.getTime().getTime()),news.getContent());
    }

    @Override
    public News getById(Integer id) throws Exception {
        String sql = "select * from news where id = ?";
        return (News) JdbcTemplate.query(sql, new BeanHandler(News.class),id);
    }

    @Override
    public List<News> getAll() throws Exception {
        String sql = "select * from news";
        return (List<News>) JdbcTemplate.query(sql, new BeanListHandler(News.class));
    }

    @Override
    public int deleteById(Integer id) throws SQLException {
        String sql = "delete from news where id = ?";
        return JdbcTemplate.update(sql, id);
    }
}

UserDaoImpl

package com.jsj.dao.Impl;

import com.jsj.dao.UserDao;
import com.jsj.entity.User;
import com.jsj.utils.BeanHandler;
import com.jsj.utils.JdbcTemplate;

public class UserDaoImpl implements UserDao {

    @Override
    public int insert(User user) throws Exception {
        String sql = "insert into user(username,password,birthday,email,tel_number) values (?,?,?,?,?)";
        return JdbcTemplate.update(sql, user.getUsername(),user.getPassword(),user.getBirthday(),user.getEmail(),user.getTelNumber());
    }

    @Override
    public User getUserByPassword(String username, String password) throws Exception {
        String sql = "select * from user where username = ? and password = ?";
        return (User) JdbcTemplate.query(sql,new BeanHandler(User.class),username, password);
    }

}