本文通過一個demo，介紹如何使用spring+mybatis管理多個數據源，注意，本文的事務管理并非之前博文介紹的分布式事務。

這個demo將使用兩個事務管理器分別管理兩個數據源。對于每一個獨立的事務，只涉及一個數據源。

demo功能：實現一個能依靠兩個獨立的事務管理器互不干涉的管理自己的數據源的web demo。

demo將實現：

1.獨立地控制兩個不同的數據源的事務管理器。

測試方式：restful web api

使用工具：

spring4.1.1.RELEASE

mybatis 3.2.7

tomcat 7

在MySQL中建立兩個schema,分別為dev和qa。并在里面分別建立一張名字表。

schema:dev

table:namaDev

id | nameDev

scheme:qa

table:nameQa

id | nameQa

對應的sql為

 1 CREATE SCHEMA `qa` DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci ; 2 CREATE SCHEMA `dev` DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci ; 3  4  CREATE  TABLE `dev`.`nameDev` ( 5   `id` BIGINT NOT NULL AUTO_INCREMENT , 6   `nameDev` VARCHAR(45) NULL , 7   PRIMARY KEY (`id`) , 8   UNIQUE INDEX `id_UNIQUE` (`id` ASC) ); 9 10   CREATE  TABLE `qa`.`nameQa` (11   `id` BIGINT NOT NULL AUTO_INCREMENT ,12   `nameQa` VARCHAR(45) NULL ,13   PRIMARY KEY (`id`) ,14   UNIQUE INDEX `id_UNIQUE` (`id` ASC) );

代碼分析：

本項目使用spring框架，因此首先配置相關bean

 1 <?xml version="1.0" encoding="UTF-8"?> 2 <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 3        xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context" 4        xmlns:tx="http://www.springframework.org/schema/tx" xmlns:jdbc="http://www.springframework.org/schema/jdbc" 5        xmlns:rabbit="http://www.springframework.org/schema/rabbit" 6        xmlns:cache="http://www.springframework.org/schema/cache" xmlns:task="http://www.springframework.org/schema/task" 7        xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc.xsd http://www.springframework.org/schema/rabbit http://www.springframework.org/schema/rabbit/spring-rabbit.xsd 8        http://www.springframework.org/schema/cache http://www.springframework.org/schema/cache/spring-cache.xsd http://www.springframework.org/schema/task http://www.springframework.org/schema/task/spring-task.xsd"> 9     <context:component-scan base-package="com.xy">10         <context:exclude-filter type="annotation" expression="org.springframework.stereotype.Controller"/>11     </context:component-scan>12     <context:property-placeholder location="classpath:context/database.properties"/>13     <tx:annotation-driven/>14 15     <bean id="qadataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"16                  destroy-method="close">17         <property name="jdbcUrl" value="${qa.db.url}"></property>18         <property name="driverClass" value="com.mysql.jdbc.Driver"></property>19         <property name="user" value="${qa.db.user}"></property>20         <property name="passWord" value="${qa.db.password}"></property>21         <property name="maxPoolSize" value="20"></property>22         <property name="minPoolSize" value="20"></property>23         <property name="initialPoolSize" value="20"></property>24         <property name="maxIdleTime" value="200"></property>25         <!--<property name="numHelperThreads" value="50"></property>-->26     </bean>27 28     <bean id="devdataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"29           destroy-method="close">30         <property name="jdbcUrl" value="${dev.db.url}"></property>31         <property name="driverClass" value="com.mysql.jdbc.Driver"></property>32         <property name="user" value="${dev.db.user}"></property>33         <property name="password" value="${dev.db.password}"></property>34         <property name="maxPoolSize" value="20"></property>35         <property name="minPoolSize" value="20"></property>36         <property name="initialPoolSize" value="20"></property>37         <property name="maxIdleTime" value="200"></property>38         <!--<property name="numHelperThreads" value="50"></property>-->39     </bean>40 41 42 43 44 45     <bean id="qasqlsessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">46         <property name="dataSource" ref="qadataSource" />47         <!--<property name="mapperLocations" value="classpath*:mapper/**/*.xml" />-->48     </bean>49 50     <bean id="devsqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">51         <property name="dataSource" ref="devdataSource" />52         <!--<property name="mapperLocations" value="classpath*:mapper/**/*.xml" />-->53     </bean>54 55     <bean id="qaManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">56         <property name="dataSource" ref="qadataSource" />57     </bean>58 59     <bean id="devManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">60         <property name="dataSource" ref="devdataSource" />61     </bean>62 63 64 65     <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">66         <property name="basePackage" value="com.xy.dao"/>67         <property name="sqlSessionFactoryBeanName" value="qasqlSessionFactory" />68     </bean>69 70     <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">71         <property name="basePackage" value="com.xy.daodev"/>72         <property name="sqlSessionFactoryBeanName" value="devsqlSessionFactory" />73     </bean>74 75 76 </beans>

其中qadataSource和devdataSource是對應兩個數據庫的數據源，qasqlSessionFactory和devsqlSessionFactory是mybatis的sessionfactory,兩個MapperScannerConfigurer自動將不同數據源的sql語句文件與interface自動裝配起來。qaManager與devManage分別管理qadataSource和devdataSource的事務，互不干涉。

Model類如下：package com.xy.model

package com.xy.model;/** * Created by helloworld on 2015/1/30. */public class NameDev {    private long id;    private String nameDev;    public long getId() {        return id;    }    public void setId(long id) {        this.id = id;    }    public String getNameDev() {        return nameDev;    }    public void setNameDev(String nameDev) {        this.nameDev = nameDev;    }}

 1 package com.xy.model; 2  3 /** 4  * Created by helloworld on 2015/1/30. 5  */ 6 public class NameQa { 7     private long id; 8     private String nameQa; 9 10     public long getId() {11         return id;12     }13 14     public void setId(long id) {15         this.id = id;16     }17 18     public String getNameQa() {19         return nameQa;20     }21 22     public void setNameQa(String nameQa) {23         this.nameQa = nameQa;24     }25 }

qa數據源的mybatis mapper接口 package com.xy.dao

 1 package com.xy.dao; 2  3 import com.xy.model.NameQa; 4  5 /** 6  * Created by helloworld on 2015/1/30. 7  */ 8 public interface NameQaMapper { 9     int insert(NameQa nameQa);10 }

dev數據源的mybatis mapper接口 package com.xy.devdao

 1 package com.xy.daodev; 2  3 import com.xy.model.NameDev; 4  5 /** 6  * Created by helloworld on 2015/1/30. 7  */ 8 public interface NameDevMapper { 9     int insert(NameDev nameDev);10 }

處理事務的service

 1 package com.xy.service; 2  3 import com.xy.dao.NameQaMapper; 4 import com.xy.daodev.NameDevMapper; 5 import com.xy.model.NameDev; 6 import com.xy.model.NameQa; 7 import org.springframework.beans.factory.annotation.Autowired; 8 import org.springframework.stereotype.Service; 9 import org.springframework.transaction.annotation.Transactional;10 11 /**12  * Created by helloworld on 2015/1/30.13  */14 @Service15 public class NameService {16     @Autowired17     NameQaMapper nameQaMapper;18     @Autowired19     NameDevMapper nameDevMapper;20 21     @Transactional(value = "qaManager", rollbackFor = Exception.class)22     public void addQa(boolean withQaException) throws Exception {23         NameQa nameQa = new NameQa();24         nameQa.setNameQa("hello");25         nameQaMapper.insert(nameQa);26 27         if(withQaException){28             throw new Exception();29         }30     }31 32     @Transactional(value = "devManager", rollbackFor = Exception.class)33     public void addDev(boolean withDevException) throws Exception {34         NameDev nameDev = new NameDev();35         nameDev.setNameDev("hello");36         nameDevMapper.insert(nameDev);37 38         if(withDevException){39             throw new Exception();40         }41     }42 43 }

controller代碼

 1 package com.xy.controller; 2  3 import com.xy.service.NameService; 4 import org.springframework.beans.factory.annotation.Autowired; 5 import org.springframework.stereotype.Controller; 6 import org.springframework.ui.ModelMap; 7 import org.springframework.web.bind.annotation.RequestMapping; 8 import org.springframework.web.bind.annotation.RequestMethod; 9 import org.springframework.web.bind.annotation.RequestParam;10 11 /**12  * Created by helloworld on 2014/11/22.13  */14 @Controller15 public class mybatisController {16 17     @Autowired18     NameService nameService;19 20     @RequestMapping(value = "/addName", method = RequestMethod.POST)21     ModelMap addName(@RequestParam("withDevException") boolean withDevException,22                      @RequestParam("witQaException") boolean witQaException ) {23         try {24             nameService.addDev(withDevException);25         } catch (Exception e) {26             e.printStackTrace();27         }28 29         try {30             nameService.addQa(witQaException);31         } catch (Exception e) {32             e.printStackTrace();33         }34         return new ModelMap("true");35     }36 37 38 }

將項目打成war包，命名為mybatis.war部署在tomcat上。

測試：

1.POST http://localhost:8080/mybatis/addName.json

request parameters:

withDevException=false

witQaException=false

返回：true 兩個數據都添加成功

2.POST http://localhost:8080/mybatis/addName.json

request parameters:

withDevException=false

witQaException=true

返回：true 只有dev添加成功

源碼下載：http://files.VEVb.com/files/rain-in-sun/springmvc-mybatis-multidatasource.rar