java_Web 实战06

java_Web 实战06
在实现功能的同时要做前端的jsp和后端的servlet方面的处理,同时这里使用scv三层架构,所以要书写secvice层和dao层数据库的mapper的代码,在书写mapper时要配置xml文件

<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC"/>
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql:///db3?useSSL=false"/>
                <property name="username" value="root"/>
                <property name="password" value="123456"/>
            </dataSource>
        </environment>
    </environments>
    <mappers>
       <mapper resource="com/home/mapper/UserMapper.xml"></mapper>
        <mapper resource="com/home/mapper/ShopperMapper.xml"></mapper>
        <mapper resource="com/home/mapper/HouseMapper.xml"></mapper>
        <mapper resource="com/home/mapper/AgentMapper.xml"></mapper>
    </mappers>
</configuration>

package com.home.mapper;

import com.home.pojo.User;
import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Select;
import org.apache.ibatis.annotations.Update;

import java.util.List;

public interface UserMapper {

        @Select("select * from tb_user where username=#{username} and password=#{password} ")
        User Login(User user);
       @Insert("insert into tb_user values (#{username},#{password},#{type})")
       void insertUser(User user);
       @Select("select * from tb_user")
       List<User> selectUser();
       @Update("UPDATE tb_user set type='0' where username=#{username}")
       void approval(String username);
       @Update("update tb_user set password=#{password} where username=#{username}")
       void updatePassword(User user);
}

这里使用注解开发,大大提高了代码的书写效率

package com.home.service;

import com.home.mapper.UserMapper;
import com.home.pojo.User;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

import java.io.IOException;
import java.io.InputStream;
import java.util.List;

public class UserService {

    public User login(User user) throws IOException {
        String resource = "mybatis-config.xml";
        InputStream inputStream = Resources.getResourceAsStream(resource);
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
        SqlSession sqlSession = sqlSessionFactory.openSession();
        UserMapper userMapper = sqlSession.getMapper(com.home.mapper.UserMapper.class);
        User user1=userMapper.Login(user);
        sqlSession.close();
        // System.out.println(user1);
        return user1;
    }
    public void insertUser(User user) throws IOException {
        String resource = "mybatis-config.xml";
        InputStream inputStream = Resources.getResourceAsStream(resource);
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
        SqlSession sqlSession = sqlSessionFactory.openSession();
        UserMapper userMapper = sqlSession.getMapper(com.home.mapper.UserMapper.class);
        userMapper.insertUser(user);
        sqlSession.commit();
        sqlSession.close();

    }
    public List<User> selectUser() throws IOException {
        String resource = "mybatis-config.xml";
        InputStream inputStream = Resources.getResourceAsStream(resource);
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
        SqlSession sqlSession = sqlSessionFactory.openSession();
        UserMapper userMapper = sqlSession.getMapper(com.home.mapper.UserMapper.class);
        List<User>users=userMapper.selectUser();
        sqlSession.close();
        return users;
    }
    public void approval(String userId) throws IOException {
        String resource = "mybatis-config.xml";
        InputStream inputStream = Resources.getResourceAsStream(resource);
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
        SqlSession sqlSession = sqlSessionFactory.openSession();
        UserMapper userMapper = sqlSession.getMapper(com.home.mapper.UserMapper.class);
        userMapper.approval(userId);

        sqlSession.commit();
        sqlSession.close();

    }
    public void updatePassword(User user) throws IOException {
        String resource = "mybatis-config.xml";
        InputStream inputStream = Resources.getResourceAsStream(resource);
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
        SqlSession sqlSession = sqlSessionFactory.openSession();
        UserMapper userMapper = sqlSession.getMapper(com.home.mapper.UserMapper.class);
        userMapper.updatePassword(user);
        sqlSession.commit();
        sqlSession.close();


    }
}

同时用service层来封装对于数据库的操作,使得代码的可维护性更加强大