SpringMVC動態切換多個數據源解決方案

1.資料來源配置

 <!-- 事務  -->
    <bean id="transactionManager"
          class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="dataSource"/>
    </bean>

    <tx:annotation-driven transaction-manager
 
="transactionManager"/>

    <!-- 資料來源1 -->
    <bean id="coreDataSource" class="org.apache.commons.dbcp2.BasicDataSource" destroy-method="close">
        <property name="driverClassName">
            <value>com.mysql.jdbc.Driver</value>
        </property>
        <property
 
 name="url">
            <value>${db.mysql.core.url}</value>
        </property>
        <property name="username">
            <value>${db.mysql.core.username}</value>
        </property>
        <property name="password">
            <value>${db.mysql.core.password}</value
 
>
        </property>
        <!-- 初始化連線大小 -->
        <property name="initialSize" value="1"/>
        <!-- 連線池最大使用連線數量 -->
        <property name="maxTotal" value="20"/>
        <!-- 連線池最大空閒 -->
        <property name="maxIdle" value="20"/>
        <!-- 連線池最小空閒 -->
        <property name="minIdle" value="1"/>
        <!-- 獲取連線最大等待時間 -->
        <property name="maxWaitMillis" value="60000"/>
        <property name="validationQuery" value="select 1 from dual"/>
        <property name="testOnBorrow" value="false"/>
        <property name="testOnReturn" value="false"/>
        <property name="testWhileIdle" value="true"/>
        <!-- 配置間隔多久才進行一次檢測，檢測需要關閉的空閒連線，單位是毫秒 -->
        <property name="timeBetweenEvictionRunsMillis" value="60000"/>
        <!-- 配置一個連線在池中最小生存的時間，單位是毫秒 -->
        <property name="minEvictableIdleTimeMillis" value="28800000"/>
    </bean>

    <!-- 資料來源2 -->
    <bean id="reportDataSource" class="org.apache.commons.dbcp2.BasicDataSource" destroy-method="close">
        <property name="driverClassName">
            <value>com.mysql.jdbc.Driver</value>
        </property>
        <property name="url">
            <value>${db.mysql.report.url}</value>
        </property>
        <property name="username">
            <value>${db.mysql.report.username}</value>
        </property>
        <property name="password">
            <value>${db.mysql.report.password}</value>
        </property>
        <!-- 初始化連線大小 -->
        <property name="initialSize" value="1"/>
        <!-- 連線池最大使用連線數量 -->
        <property name="maxTotal" value="20"/>
        <!-- 連線池最大空閒 -->
        <property name="maxIdle" value="20"/>
        <!-- 連線池最小空閒 -->
        <property name="minIdle" value="1"/>
        <!-- 獲取連線最大等待時間 -->
        <property name="maxWaitMillis" value="60000"/>
        <property name="validationQuery" value="select 1 from dual"/>
        <property name="testOnBorrow" value="false"/>
        <property name="testOnReturn" value="false"/>
        <property name="testWhileIdle" value="true"/>
        <!-- 配置間隔多久才進行一次檢測，檢測需要關閉的空閒連線，單位是毫秒 -->
        <property name="timeBetweenEvictionRunsMillis" value="60000"/>
        <!-- 配置一個連線在池中最小生存的時間，單位是毫秒 -->
        <property name="minEvictableIdleTimeMillis" value="28800000"/>
    </bean>


    <bean id="dataSource" class="com.xiaomi.dev.service.datasource.DynamicDataSource">
        <property name="targetDataSources">
            <map key-type="java.lang.String">
                <entry value-ref="coreDataSource" key="core"></entry>
                <entry value-ref="reportDataSource" key="report"></entry>
            </map>
        </property>
        <!-- 預設使用server的資料來源 -->
        <property name="defaultTargetDataSource" ref="coreDataSource"></property>
    </bean>

    <!-- spring和MyBatis完美整合，不需要mybatis的配置對映檔案 -->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>
        <property name="configLocation" value="classpath:mybatis-config.xml"></property>
        <!-- 自動掃描mapping.xml檔案 -->
        <property name="mapperLocations" value="classpath:sqlmap/*.xml"></property>
    </bean>

    <bean class="org.mybatis.spring.SqlSessionTemplate">
        <constructor-arg ref="sqlSessionFactory"/>
    </bean>

2. DataSourceConst.java

public class DataSourceConst {
    public static final String CORE = "core";
    public static final String REPORT = "report";
}  

3. DynamicDataSource.java

import org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource;
public class DynamicDataSource extends AbstractRoutingDataSource {
    @Override
    protected Object determineCurrentLookupKey() {
        return DataSourceContextHolder.getDataSourceType();
    }

}  

4. DataSourceContextHolder.java

public class DataSourceContextHolder {
    private static final ThreadLocal contextHolder = new ThreadLocal();

    public static void setDataSourceType(String dataSourceType) {
        contextHolder.set(dataSourceType);
    }

    public static String getDataSourceType() {
        return (String) contextHolder.get();
    }

    public static void clearDataSourceType() {
        contextHolder.remove();
    }

}    

5. 資料庫查詢前切換到指定庫

// 切換為report庫
DataSourceContextHolder.setDataSourceType(DataSourceConst.REPORT);
// 切換為core庫
DataSourceContextHolder.setDataSourceType(DataSourceConst.CORE);