spring mvc 多数据源切换,不支持事务控制[一]

一个项目中需要使用两个数据库,Oracle 和Mysql ,于是参考各个blog,实现此功能.写好后才发现,原来的事务失效了,我去...

spring-mybatis.xml 配置

    <bean id="configReader" class="org.springframework.beans.factory.config.PreferencesPlaceholderConfigurer">
        <property name="locations">
            <list>
                <value>classpath:spring/db.properties</value>
            </list>
        </property>
        <property name="ignoreResourceNotFound" value="true"/>
    </bean>

    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="driverClass" value="${jdbc.oracle.DriverClassName}"></property>
        <property name="jdbcUrl" value="${jdbc.oracle.Url}"></property>
        <property name="user" value="${jdbc.oracle.UserName}"></property>
        <property name="password" value="${jdbc.oracle.UserPassword}"></property>

        <property name="acquireIncrement" value="5"></property>
        <property name="initialPoolSize" value="5"></property>
        <property name="maxIdleTime" value="60"></property>
        <property name="maxPoolSize" value="100"></property>
        <property name="minPoolSize" value="5"></property>
    </bean>

    <!-- 配置数据源:MySQL start -->
    <bean name="mySqlDataSource" class="com.alibaba.druid.pool.DruidDataSource"
          init-method="init" destroy-method="close">
        <property name="driverClassName" value="${jdbc.mysql.DriverClassName}"/>
        <property name="url" value="${jdbc.mysql.Url}"/>
        <property name="username" value="${jdbc.mysql.UserName}"/>
        <property name="password" value="${jdbc.mysql.UserPassword}"/>

        <!-- 初始化连接大小 -->
        <property name="initialSize" value="5"/>
        <!-- 连接池最大使用连接数量 -->
        <property name="maxActive" value="30"/>
        <!-- 连接池最小空闲 -->
        <property name="minIdle" value="2"/>
        <!-- 获取连接最大等待时间 -->
        <property name="maxWait" value="300"/>

        <property name="validationQuery" value="SELECT 1"/>
        <property name="testOnBorrow" value="false"/>
        <property name="testOnReturn" value="false"/>
        <property name="testWhileIdle" value="true"/>

        <!-- 配置间隔多久才进行一次检测，检测需要关闭的空闲连接，单位是毫秒 -->
        <property name="timeBetweenEvictionRunsMillis" value="10000"/>
        <!-- 配置一个连接在池中最小生存的时间，单位是毫秒 -->
        <property name="minEvictableIdleTimeMillis" value="30000"/>

        <!-- 打开removeAbandoned功能 -->
        <property name="removeAbandoned" value="true"/>
        <!-- 1800秒，也就是30分钟 -->
        <property name="removeAbandonedTimeout" value="1800"/>
        <!-- 关闭abanded连接时输出错误日志 -->
        <property name="logAbandoned" value="true"/>

        <!-- 监控数据库 -->
        <property name="filters" value="stat"/>
    </bean>

    <bean id="multipleDataSource" class="com.we.database.MultipleDataSource">
        <property name="defaultTargetDataSource" ref="dataSource"/>
        <property name="targetDataSources">
            <map>
                <entry key="oracleDataSource" value-ref="dataSource"/>
                <entry key="mySqlDataSource" value-ref="mySqlDataSource"/>
            </map>
        </property>
    </bean>

    <!-- oracle myBatis file -->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="multipleDataSource"/>
        <!--<property name="configLocation" value="classpath:configuration.xml" /> -->
        <property name="mapperLocations" value="classpath:com/we/dao/mapper/*.xml"/>
    </bean>

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

    <!-- configure transaction -->
    <bean id="transactionManager"
          class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="dataSource"/>  后面发现是这里写错了应该是 ref="multipleDataSource"
    </bean>

    <!-- annotation transaction -->
    <tx:annotation-driven transaction-manager="transactionManager" proxy-target-class="true"/>

    <!-- interception transatcion -->
    <tx:advice id="transactionAdvice" transaction-manager="transactionManager">
        <tx:attributes>
            <tx:method name="add*" propagation="REQUIRED"/>
        </tx:attributes>
    </tx:advice>

    <!-- 配置数据库注解aop -->
    <bean id="dataSourceAspect" class="com.we.database.DataSourceAspect"/>

    <aop:config>
        <aop:pointcut id="transactionPointcut" expression="execution(* com.wewe.licai.service..*Impl.*(..))"/>
        <aop:advisor pointcut-ref="transactionPointcut" advice-ref="transactionAdvice" order="2"/>

        <!--数据源选择切面,保证在事务开始之前执行-->
        <aop:advisor pointcut-ref="transactionPointcut" advice-ref="dataSourceAspect"  order="1" />
    </aop:config>

@Documented
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.METHOD,ElementType.TYPE})

public @interface DataSource {
     String name() default DataSource.oracleDataSource;
     String mySqlDataSource = "mySqlDataSource";
     String oracleDataSource = "oracleDataSource";
}

注解切换，默认使用oracle数据源

/**
 * Created by eastday on 2017/9/21.
 */
public class DataSourceAspect implements MethodBeforeAdvice,AfterReturningAdvice
{

    @Override
    public void afterReturning(Object returnValue, Method method,
                               Object[] args, Object target) throws Throwable {

        MultipleDataSource.clearDataSource();
    }

    @Override
    public void before(Method method, Object[] args, Object target)
            throws Throwable {

        //首先取类上的数据源
        if(method.getDeclaringClass().isAnnotationPresent(DataSource.class) && !method.isAnnotationPresent(DataSource.class)) {

            DataSource datasource = method.getDeclaringClass().getAnnotation(DataSource.class);
            MultipleDataSource.setDataSource(datasource.name());

            //方法上的数据源 优先级高于类上的
        } else if (method.isAnnotationPresent(DataSource.class)) {

            DataSource datasource = method.getAnnotation(DataSource.class);
            MultipleDataSource.setDataSource(datasource.name());
        }
        else
        {
            MultipleDataSource.setDataSource(DataSource.oracleDataSource);
        }
    }
}

注解方式实现切换数据源,搜索注释,更换注释上面的数据源,支持类注释和方法注释

public class MultipleDataSource extends AbstractRoutingDataSource {
    private static final ThreadLocal<String> dataSources = new InheritableThreadLocal<String>();

    public static void setDataSource(String dataSource) {
        dataSources.set(dataSource);
    }

    //清除数据源
    public static void clearDataSource() {
        dataSources.remove();
    }

    @Override
    protected Object determineCurrentLookupKey() {
        return dataSources.get();
    }
}

继承AbstractRoutingDataSource实现数据源切换

@DataSource(name = DataSource.mySqlDataSource)
public class ContentServiceImpl implements IContentService {

    @Autowired
    private IContentDao contentDao;

    @Override
    public Content queryOne(String type) {
        return contentDao.queryOne(type);
    }
}

使用demo