Spring + Mybatis 框架整合（ssm）

開言

maven + spring mvc項目架構構建，利用intelliJ Idea 快速創建，省去了導包的煩惱。
maven
spring mvc

mybatis依賴添加

 <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis</artifactId>
      <version>3.4.1</version>
  </dependency>

方案一

在添加了spring、mybatis、數據庫驅動等基本依賴後，可以添加以下幾個依賴，進而整合Spring、Mybatis兩大框架。

 	<!-- https://mvnrepositcory.com/artifact/org.mybatis/mybatis-spring -->
    <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis-spring</artifactId>
      <version>1.3.2</version>
    </dependency>

    <!-- https://mvnrepository.com/artifact/com.alibaba/druid -->
    <dependency>
      <groupId>com.alibaba</groupId>
      <artifactId>druid</artifactId>
      <version>1.1.20</version>
    </dependency>

web.xml

<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee
                      http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
	version="3.1" metadata-complete="true">
	<!-- 如果是用mvn命令生成的xml，需要修改servlet版本爲3.1 -->
	<!-- 配置DispatcherServlet -->
	<servlet>
		<servlet-name>mvc-dispatcher</servlet-name>
		<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
		<!-- 配置springMVC需要加載的配置文件
			spring-dao.xml,spring-service.xml,spring-web.xml
			Mybatis - > spring -> springmvc
		 -->
		<init-param>
			<param-name>contextConfigLocation</param-name>
			<param-value>classpath:spring/spring-*.xml</param-value>
		</init-param>
	</servlet>
	<servlet-mapping>
		<servlet-name>mvc-dispatcher</servlet-name>
		<!-- 默認匹配所有的請求 -->
		<url-pattern>/</url-pattern>
	</servlet-mapping>
</web-app>

在resources/spring文件夾下，創建三個spring-*.xml文件，全部配置爲spring mvc的應用上下文，分別處理dao、web、service三層，還有在resources下添加一個application.properties文件用於配置spring、數據庫連接池佔位符。

以下貼出，這幾個文件
spring-web

<?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:mvc="http://www.springframework.org/schema/mvc"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/mvc https://www.springframework.org/schema/mvc/spring-mvc.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd">
    <mvc:default-servlet-handler/>
</beans>

spring-dao

<?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.xsd
	http://www.springframework.org/schema/context
	http://www.springframework.org/schema/context/spring-context.xsd">
	  <!--
       <bean id="propertyConfig" class="org.springframework.beans.factory.config.PreferencesPlaceholderConfigurer">
           <property name="location" value="classpath:application.properties"/>
       </bean>
       <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource>
        <property name="autoCommitOnClose" value="true"/>
        <property name="driverClass" value="${driverClass}"/>
        <property name="jdbcUrl" value="${jdbcUrl}"/>
        <property name="user" value="${user}"/>
        <property name="password" value="${password}"/>
    </bean>
        -->


    <context:property-placeholder location="classpath:application.properties"/>

    <bean class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="druidDataSource"/>
        <property name="mapperLocations" value="classpath:mapper/test.xml"/>

    </bean>

    <bean id="druidDataSource" class="com.alibaba.druid.pool.DruidDataSource">
        <property name="driverClassName" value="${jdbc.driverClassName}"/>
        <property name="url" value="${jdbc.url}"/>
        <property name="username" value="${jdbc.username}"/>
        <property name="password" value="${jdbc.password}"/>
        <property name="defaultAutoCommit" value="true"/>
    </bean>

    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <property name="sqlSessionFactoryBeanName" value="sql"/>
        <property name="basePackage" value="mybatis.test"/>
    </bean>

</beans>

spring-service

<?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:mvc="http://www.springframework.org/schema/mvc"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd   http://www.springframework.org/schema/mvc https://www.springframework.org/schema/mvc/spring-mvc.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd">
    <context:component-scan base-package="controller"/>
    <mvc:annotation-driven>
        <mvc:message-converters>
            <bean class="org.springframework.http.converter.StringHttpMessageConverter"/>
        </mvc:message-converters>
    </mvc:annotation-driven>

</beans>

application.properties

#mybatis
jdbc.driverClassName=oracle.jdbc.OracleDriver
jdbc.url=jdbc:oracle:thin:@localhost:1521:orcl
jdbc.username=system
jdbc.password=Open1234

這裏推薦一個GitHub優秀項目，手把手教你最優雅整合ssm框架

方案二

在添加了spring、mybatis、數據庫驅動等基本依賴後，可以添加以下幾個依賴，進而整合Spring、Mybatis兩大框架。

 	<!-- https://mvnrepository.com/artifact/org.mybatis/mybatis-spring -->
    <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis-spring</artifactId>
      <version>1.3.2</version>
    </dependency>
    <!-- https://mvnrepository.com/artifact/com.mchange/c3p0 -->
    <dependency>
      <groupId>com.mchange</groupId>
      <artifactId>c3p0</artifactId>
      <version>0.9.5.2</version>
    </dependency>

dispatcher-servlet.xml

<?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:mv="http://www.springframework.org/schema/cache"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/cache http://www.springframework.org/schema/cache/spring-cache.xsd http://www.springframework.org/schema/mvc https://www.springframework.org/schema/mvc/spring-mvc.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd">
    <context:component-scan base-package="controller"/>
    <mvc:annotation-driven>
        <mvc:message-converters>
            <bean class="org.springframework.http.converter.StringHttpMessageConverter"/>
        </mvc:message-converters>
    </mvc:annotation-driven>

    <bean class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>
        <property name="mapperLocations" value="classpath:mapper/test.xml"/>
    </bean>

    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="driverClass" value="oracle.jdbc.OracleDriver"/>
        <property name="jdbcUrl" value="jdbc:oracle:thin:@localhost:1521:orcl"/>
        <property name="user" value="system"/>
        <property name="password" value="Open1234"/>
        <property name="autoCommitOnClose" value="true"/>
    </bean>
    
</beans>

配置數據庫連接池

 <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="driverClass" value="oracle.jdbc.OracleDriver"/>
        <property name="jdbcUrl" value="jdbc:oracle:thin:@localhost:1521:orcl"/>
        <property name="user" value="system"/>
        <property name="password" value="Open1234"/>
        <property name="autoCommitOnClose" value="true"/>
  </bean>

如你所見，ComboPooledDataSource這個bean，用於配置有關數據庫連接的必要參數（這裏我用的是oracle數據庫），同時交由spring容器管理。

通過properties文件配置數據庫連接池

<bean id="propertyConfig" class="org.springframework.beans.factory.config.PreferencesPlaceholderConfigurer">
        <property name="location" value="classpath:config.properties"/>
</bean>

<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">

     <!--
     <property name="driverClass" value="oracle.jdbc.OracleDriver"/>
     <property name="jdbcUrl" value="jdbc:oracle:thin:@localhost:1521:orcl"/>
     <property name="user" value="system"/>
     <property name="password" value="Open1234"/>
     -->
     <property name="autoCommitOnClose" value="true"/>
  
     <property name="driverClass" value="${driverClass}"/>
     <property name="jdbcUrl" value="${jdbcUrl}"/>
     <property name="user" value="${user}"/>
     <property name="password" value="${password}"/>
</bean>

配置SqlSessionFactory工廠

<bean class="org.mybatis.spring.SqlSessionFactoryBean">
     <property name="dataSource" ref="dataSource"/>
     <property name="mapperLocations" value="classpath:mapper/test.xml"/>
</bean>

添加數據庫連接池，同時添加XML映射文件。這裏有個問題，映射器接口沒有由spring容器管理，那麼可以這樣做：

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

指定映射器接口路徑，這樣的最大的好處就是，映射器接口由spring容器管理，同時也可以通過註釋來指定映射器行爲，而且也可以利用spring的特性快速開發，如利用註釋@Autowired 直接引用映射器。這樣，可以不用添加XML映射文件。

控制器例子

package controller;
import mybatis.test.*;
import org.apache.ibatis.session.SqlSession;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class HelloController {
    @Autowired
    test t;
    //@Autowired
    //SqlSessionFactoryBean sqlSessionFactoryBean;
    @RequestMapping("/hello")
    public String sayHello() throws Exception {
        //SqlSession session = sqlSessionFactoryBean.getObject().openSession(true);
        //t = session.getMapper(test.class);
        return "hello "+t.getName();
    }
}

Spring框架聲明式事務管理

	<!--配置Spring框架聲明式事務管理-->
    <!--配置事務管理器-->
    <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="dataSource" />
    </bean>

    <!--配置事務通知-->
    <tx:advice id="txAdvice" transaction-manager="transactionManager">
        <tx:attributes>
            <tx:method name="find*" read-only="true"/>
            <tx:method name="*" isolation="DEFAULT"/>
        </tx:attributes>
    </tx:advice>

    <!--配置AOP增強-->
    <aop:config>
        <aop:advisor advice-ref="txAdvice" pointcut="execution(* com.gx.service.Impl.*ServiceImpl.*(..))"/>
  	</aop:config>