Mybatis和Spring的整合

一 创建工程

1.1 在pom文件中导入jar包

<dependencies>
        <!-- mybatis核心包 -->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.4.1</version>
        </dependency>
        <!-- mysql驱动包 -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.29</version>
        </dependency>
        <!-- junit测试包 -->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>
        <!--日志包-->
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-log4j12</artifactId>
            <version>1.6.1</version>
        </dependency>
        <!--spring数据库-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>4.3.11.RELEASE</version>
        </dependency>
        <!--aop-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-aspects</artifactId>
            <version>4.3.11.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjweaver</artifactId>
            <version>1.8.0</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>4.3.11.RELEASE</version>
        </dependency>
        <!--spring-mybatis整合包-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>1.3.1</version>
        </dependency>
        <!--spring相关包-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>4.3.11.RELEASE</version>
        </dependency>
   </dependencies>
    <!--配置资源文件扫描，否则Mapper-->
    <build>
        <resources>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.xml
                
                true
            
            
                src/main/resources
                
                    **/*.xml</include>
                    <include>**/*.properties
                
            
        
    

1.2 建立工程完整目录

1.3 配置文件内容

jdbc

jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/databasename?characterEncoding=utf-8
jdbc.username=
jdbc.password=

log4j

# For all other servers: Comment out the Log4J listener in web.xml to activate Log4J.
log4j.rootLogger=DEBUG, stdout
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d %p [%c] - %m%n
#begin
#for normal test,delete when online
log4j.logger.com.ibatis=DEBUG
log4j.logger.com.ibatis.common.jdbc.SimpleDataSource=DEBUG
log4j.logger.com.ibatis.common.jdbc.ScriptRunner=DEBUG
log4j.logger.com.ibatis.sqlmap.engine.impl.SqlMapClientDelegate=DEBUG
log4j.logger.java.sql.Connection=DEBUG
log4j.logger.java.sql.Statement=DEBUG
log4j.logger.java.sql.PreparedStatement=DEBUG
log4j.logger.java.sql.ResultSet=DEBUG

1.4 pojo and mapper

public class Dept implements Serializable {
     
    private Integer id;
    private String name;

    @Override
    public String toString() {
     
        return "Dept{" +
                "id=" + id +
                ", name='" + name + '\'' +
                '}';
    }

    public Integer getId() {
     
        return id;
    }

    public void setId(Integer id) {
     
        this.id = id;
    }

    public String getName() {
     
        return name;
    }

    public void setName(String name) {
     
        this.name = name;
    }
}

<?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" >
<mapper namespace="com.dao.DeptDAO">

    <select id="getDeptById" resultType="Dept">
        SELECT
            id,
            name
        FROM dept
        WHERE id = #{
     id}
    </select>

    <insert id="addDept" parameterType="Dept" keyProperty="id" useGeneratedKeys="true">
        insert into DEPT(name) VALUES (#{
     name})
    </insert>
</mapper>

二 Spring-Mybatis整合

Spring负责管理数据源，加载Mybatis配置文件，Mybatis的session和事务

2.1 spring用来管理数据源

<?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" xmlns:tx="http://www.springframework.org/schema/tx"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.2.xsd
  http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.2.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd">

	
    <context:property-placeholder location="jdbc.properties" ignore-unresolvable="true"/>

    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="${jdbc.driver}"/>
        <property name="url" value="${jdbc.url}"/>
        <property name="username" value="${jdbc.username}"/>
        <property name="password" value="${jdbc.password}"/>
    </bean>
</beans>

2.2 存在Mybatis配置文件时spring的配置

注意：mybatis配置文件中不需再写mapper映射文件的配置

    <bean id="sessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>
        <property name="configLocation"value="classpath:mybatis-config.xml"/>
        <property name="typeAliasesPackage" value="com.pojo"/>
        <property name="mapperLocations" value="classpath:com/dao/mapper/*.xml"/>
    </bean>

2.3 省略mybatis配置文件时spring的配置

    <bean id="sessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>
        <property name="typeAliasesPackage" value="com.pojo"/>
        <property name="mapperLocations" value="classpath:com/dao/mapper/*.xml"/>
    </bean>

2.4 Dao的基本整合

2.4.1 编写Dao的实现类

package com.dao;


import com.pojo.Dept;

public interface DeptDAO {
     

    Dept getDeptById(Integer id);
    void addDept(Dept dept);
}

package com.dao;

import com.pojo.Dept;
import org.mybatis.spring.support.SqlSessionDaoSupport;


    public class DeptDAOImpl extends SqlSessionDaoSupport implements DeptDAO {
     

    @Override
    public Dept getDeptById(Integer id) {
     
        //
        return super.getSqlSession().selectOne("DEPT.getDeptById", id);
    }

    @Override
    public void addDept(Dept dept) {
     
        super.getSqlSession().insert("com.dao.DeptDAO.addDept",dept);
    }

}

2.4.2 声明DeptDao的Bean

<!--    <bean id="deptDAO" class="com.dao.impl.DeptDAOImpl">-->
<!--        <property name="sqlSessionFactory" ref="sessionFactory"/>-->
<!--    </bean>-->

测试代码

public class SpringMybatisTest {
     

    ApplicationContext applicationContext = new ClassPathXmlApplicationContext("spring-config.xml");

    @Test
    public void testSelect() {
     
        DeptDAO deptDAO = (DeptDAO) applicationContext.getBean("deptDAO");
        Dept dept=new Dept();
        dept.setName("aaa");
        deptDAO.addDept(dept);
    }
}

2.4.3 直接面向接口整合

mybatis可以没有实现类，但mapper映射文件的namespace必须是接口的全路径。接口中方法名与sql语句的id必须一致。

spring配置如下：

<!--    <bean id="DeptDAO" class="org.mybatis.spring.mapper.MapperFactoryBean">-->
<!--        <property name="mapperInterface" value="com.dao.DeptDAO"/>-->
<!--        <property name="sqlSessionFactory" ref="sessionFactory"/>-->
<!--    </bean>-->

测试代码如下:

    @Test
    public void testDeptDAO(){
     
        DeptDAO dao= (DeptDAO) applicationContext.getBean("DeptDAO");
        Dept dept=dao.getDeptById(1);
        System.out.println(dept);
    }

2.4.4 对接口整合的简化

当存在多个接口时，可以统一扫描，不需要为每一个接口声明一个Bean
spring配置

    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <property name="basePackage" value="com.dao"/>
    </bean>

spring在扫描后会自动生成接口对应的Bean(接口名字的首字母小写),在具体代码中，通过mapper文件的namespace来确定调用哪个mapper

    @Test
    public void testSelect() {
     
        DeptDAO deptDAO = (DeptDAO) applicationContext.getBean("deptDAO");
        Dept dept=new Dept();
        dept.setName("aaa");
        deptDAO.addDept(dept);
    }

2.5 spring中对事务的管理

spring中事务的管理都是由切面来完成的,未设置事务管理时，每一个crud都是独自提交，无法完成业务需求的
在service包中建立相应的类:

@Service
public class DeptService {
     
    @Autowired
    private DeptDAO deptDAO;//此处的DAO不能自己去new

    public void add(Dept dept) throws Exception {
     
        deptDAO.addDept(dept);
        deptDAO.addDept(dept);
        throw new Exception("我是测试的异常");
    }
}

我手动抛出异常，在设置事务管理后，数据并不会插入到数据库中，但是未设置事务管理时，即使有异常抛出，数据仍然会插入数据库中
speing的配置

<!--扫描service包下的service注解，自动生成相应的Bean-->
<context:component-scan base-package="com.service">
        <context:include-filter type="annotation" expression="org.springframework.stereotype.Service"/>
    </context:component-scan>

<!--配置事务管理器，指定数据源-->
 <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="dataSource"/>
</bean>

<!--配置事务通知-->
<tx:advice id="txAdvice" transaction-manager="transactionManager">
        <tx:attributes>
        	<!--对add开头的方法，有异常则回滚-->
            <tx:method name="add*" rollback-for="Exception" isolation="SERIALIZABLE"/>
            <tx:method name="update*" rollback-for="Exception"/>
            <tx:method name="delete*" rollback-for="Exception"/>
            <!--对get开头的方法设置只读-->
            <tx:method name="get*" read-only="true"/>
        </tx:attributes>
    </tx:advice>

<!--配置切面，指定要事务管理的方法-->
<aop:config >
        <aop:pointcut id="point" expression="execution(* com.service..*(..))"/>
        <aop:advisor advice-ref="txAdvice" pointcut-ref="point"/>
    </aop:config>