mybatis和Spring的整合

整合思路
需要spring通过单例方式管理SqlSessionFactory。spring和mybatis整合生成代理对象，使用SqlSessionFactory创建SqlSession。（spring和mybatis整合自动完成）持久层的mapper都需要由spring进行管理。
整合环境
jar包：   <!--junit配置-->        <dependency>            <groupId>junit</groupId>            <artifactId>junit</artifactId>            <version>4.12</version>            <scope>test</scope>        </dependency>        <dependency>            <groupId>javaee</groupId>            <artifactId>javaee-api</artifactId>            <version>5</version>        </dependency>        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-core</artifactId>            <version>4.2.2.RELEASE</version>        </dependency>        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-beans</artifactId>            <version>4.2.2.RELEASE</version>        </dependency>        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-context</artifactId>            <version>4.2.2.RELEASE</version>        </dependency>        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-tx</artifactId>            <version>4.1.9.RELEASE</version>        </dependency>        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-aspects</artifactId>            <version>4.2.1.RELEASE</version>        </dependency>        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-context-support</artifactId>            <version>4.1.9.RELEASE</version>        </dependency>        <!-- spring-jdbc -->        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-jdbc</artifactId>            <version>4.3.9.RELEASE</version>        </dependency>        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-test</artifactId>            <version>4.1.9.RELEASE</version>        </dependency>        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-web</artifactId>            <version>4.2.3.RELEASE</version>        </dependency>        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-webmvc</artifactId>            <version>4.1.9.RELEASE</version>        </dependency>        <dependency>            <groupId>org.mybatis</groupId>            <artifactId>mybatis</artifactId>            <version>3.2.7</version>        </dependency>        <dependency>            <groupId>org.mybatis</groupId>            <artifactId>mybatis-spring</artifactId>            <version>1.2.2</version>        </dependency>        <dependency>            <groupId>mysql</groupId>            <artifactId>mysql-connector-java</artifactId>            <version>5.1.38</version>        </dependency>        <dependency>            <groupId>org.javassist</groupId>            <artifactId>javassist</artifactId>            <version>3.17.1-GA</version>        </dependency>        <dependency>            <groupId>cglib</groupId>            <artifactId>cglib</artifactId>            <version>2.2.2</version>        </dependency>        <dependency>            <groupId>c3p0</groupId>            <artifactId>c3p0</artifactId>            <version>0.9.1.2</version>        </dependency>        <dependency>            <groupId>org.apache.commons</groupId>            <artifactId>commons-dbcp2</artifactId>            <version>2.1</version>        </dependency>        <dependency>            <groupId>commons-dbcp</groupId>            <artifactId>commons-dbcp</artifactId>            <version>1.4</version>        </dependency>        <dependency>            <groupId>org.hamcrest</groupId>            <artifactId>hamcrest-all</artifactId>            <version>1.3</version>            <scope>test</scope>        </dependency>    </dependencies>    <build>        <resources>            <resource>                <directory>src/main/java</directory>                <includes>                    <include>**/*.xml</include>                </includes>            </resource>        </resources>    </build>
sqlSessionFactory
在applicationContext.xml配置sqlSessionFactory和数据源sqlSessionFactory在mybatis和spring的整合包下。<beans xmlns="http://www.springframework.org/schema/beans"       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:mvc="http://www.springframework.org/schema/mvc"       xmlns:context="http://www.springframework.org/schema/context"       xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"       xsi:schemaLocation="http://www.springframework.org/schema/beans        http://www.springframework.org/schema/beans/spring-beans-3.2.xsd        http://www.springframework.org/schema/mvc        http://www.springframework.org/schema/mvc/spring-mvc-3.2.xsd        http://www.springframework.org/schema/context        http://www.springframework.org/schema/context/spring-context-3.2.xsd        http://www.springframework.org/schema/aop        http://www.springframework.org/schema/aop/spring-aop-3.2.xsd        http://www.springframework.org/schema/tx        http://www.springframework.org/schema/tx/spring-tx-3.2.xsd ">    <!-- 加载配置文件 -->    <context:property-placeholder location="classpath:db.properties" />    <!-- 数据源，使用dbcp -->    <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource"          destroy-method="close">        <property name="driverClassName" value="${jdbc.driver}" />        <property name="url" value="${jdbc.url}" />        <property name="username" value="${jdbc.username}" />        <property name="password" value="${jdbc.password}" />        <property name="maxActive" value="10" />        <property name="maxIdle" value="5" />    </bean>    <!-- sqlSessinFactory -->    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">        <!-- 加载mybatis的配置文件 -->        <property name="configLocation" value="mybatis/SqlMapConfig.xml" />        <!-- 数据源 -->        <property name="dataSource" ref="dataSource" />    </bean></beans>
User.xml
<?xml version="1.0" encoding="UTF-8" ?><!DOCTYPE mapper        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"        "http://mybatis.org/dtd/mybatis-3-mapper.dtd"><!-- namespace 命名空间，作用就是对sql进行分类化管理,理解为sql隔离 注意：使用mapper代理方法开发，namespace有特殊重要的作用 --><mapper namespace="test">    <!-- 在映射文件中配置很多sql语句 -->    <!--需求:通过id查询用户表的记录 -->    <!-- 通过select执行数据库查询     id:标识映射文件中的sql，称为statement的id     将sql语句封装到mappedStatement对象中，所以将id称为statement的id     parameterType:指定输入参数的类型     #{}标示一个占位符,     #{value}其中value表示接收输入参数的名称，如果输入参数是简单类型，那么#{}中的值可以任意。     resultType：指定sql输出结果的映射的java对象类型，select指定resultType表示将单条记录映射成java对象     -->    <select id="findUserById" parameterType="int" resultType="com.iot.ssm.po.User">        SELECT * FROM  user  WHERE id=#{value}    </select></mapper>dao(实现类继承SqlSessionDaoSupport)public interface UserDao {    //根据id查询用户信息    public User findUserById(int id) throws Exception;}dao接口实现类需要注入SqlSessoinFactory，通过spring进行注入。这里spring声明配置方式，配置dao的bean
UserDaoImpl实现类继承SqlSessionDaoSupport
public class UserDaoImpl extends SqlSessionDaoSupport implements UserDao{    @Override    public User findUserById(int id) throws Exception {        //继承SqlSessionDaoSupport，通过this.getSqlSession()得到sqlSessoin        SqlSession sqlSession = this.getSqlSession();        User user = sqlSession.selectOne("test.findUserById",id);        return user;    }}
通过MapperFactoryBean创建代理对象
<!-- mapper配置    MapperFactoryBean：根据mapper接口生成代理对象    --><bean id="userMapper" class="org.mybatis.spring.mapper.MapperFactoryBean">        //mapperInterface指定mapper接口        <property name="mapperInterface" value="com.iot.ssm.mapper.UserMapper"/>        <property name="sqlSessionFactory" ref="sqlSessionFactory"/></bean>
通过MapperScannerConfigurer进行dao包下的扫描
!-- mapper批量扫描，从mapper包中扫描出mapper接口，自动创建代理对象并且在spring容器中注册    遵循规范：将mapper.java和mapper.xml映射文件名称保持一致，且在一个目录 中    自动扫描出来的mapper的bean的id为mapper类名（首字母小写）    --><bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">    <!-- 指定扫描的包名    如果扫描多个包，每个包中间使用半角逗号分隔    -->    <property name="basePackage" value="com.iot.ssm.mapper"/>    <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/></bean>
//之前daoimpl包 减少了代码的繁琐 后续就用不上了
public List<User> getUserList(User user) {        /*方法一：SqlsessionFactoryBean          SqlSessionTemplate构造注入吧?*/       //   return sqlSession.selectList("cn.happy.dao.UserMapper.getUserList",user);      //方法二：继承 extends SqlSessionDaoSupport并且他其中有一setSqlSessionFauorty方法getSqlSession设置注入     /* SqlSessionDaoSupport         设置注入SqlSessionFauorty*/        // return this.getSqlSession().selectList("cn.happy.dao.UserMapper.getUserList",user);       /* cn.happy.dao.UserMapper.getUserList如果错了  编译时是不知道的，运行时才知道*/       /* Sqlsession.selectList采用字符串来指定映射项  字符串形式的不确定性        Sqlsession.getMapper需要在每次调用的时都实现一次映射器接口*/        //注入映射器实现（使在IOC接口一直存在一个映射器不用每次都调用一个*******）        return this.getSqlSession().getMapper(UserMapper.class).getUserList(user);       //之前没结合的一大堆等等代码。。。。。。。繁琐  上面简便的一句话        /* List<User> list=new ArrayList<User>();        list=sqlSession.selectList("cn.happy.dao.UserMapper.getUserList",user);        return list;*/    }
<!--Service-->    <!--扫描注解定义-->
     <conctext:component-scan base-package="cn.happy.service"></conctext:component-scan>
    <!--事务管理器-->
    <bean id="txManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">        <property name="dataSource" ref="dataSource"></property>    </bean>
    <!--将 事务增强，配置切面 注释 写(使用注解事先声明式事务处理)-->
     <tx:annotation-driven transaction-manager="txManager"/>