Spring Study-lesson13-整合Mybatis-2-2023-3-19

进一步优化

将UserMapperImpl 进行优化，继承系统提供的一个父类：extends SqlSessionDaoSupport  

新建一个：UserMapperImpl2类  继承父类，实现UserMapper接口 。简化成一行代码

package com.feijian.mapper;

import com.feijian.pojo.User;
import org.apache.ibatis.session.SqlSession;
import org.mybatis.spring.support.SqlSessionDaoSupport;

import java.util.List;

public class UserMapperImpl2 extends SqlSessionDaoSupport implements UserMapper {

    @Override
    public List<User> selectUser() {
        return getSqlSession().getMapper(UserMapper.class).selectUser();
    }
}

写完新类，到ApplicationContext.xml种注册 bean - userMapper2 这里它的属性就是sqlSessionFactory 

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
           http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
           http://www.springframework.org/schema/context
           http://www.springframework.org/schema/context/spring-context.xsd
           http://www.springframework.org/schema/aop
           http://www.springframework.org/schema/aop/spring-aop.xsd">

    <import resource="spring-dao.xml"/>

    <bean id="userMapper" class="com.feijian.mapper.UserMapperImpl">
        <property name="sqlSession" ref="sqlSession"/>
    </bean>

    <bean id="userMapper2" class="com.feijian.mapper.UserMapperImpl2">
        <property name="sqlSessionFactory" ref="sqlSessionFactory"/>
    </bean>
</beans>