SSH多数据源配置

Spring2.0.1以后的版本已经支持配置多数据源，并且可以在运行的时候动态加载不同的数据源。通过继承AbstractRoutingDataSource就可以实现多数据源的动态转换。目前做的项目就是需要访问12个数据源，每个数据源的表结构都是相同的，所以要求数据源的变动对于编码人员来说是透明，也就是说同样SQL语句在不同的环境下操作的数据库是不一样的。具体的配置如下：

一、首先需要写一个静态的键值对照类：

package cn.sunline.suncard.sde.dp.db;    public class DataSourceMap {  public static final String acd="ACD";  public static final String trm= "TRM";  } 

 

这个类主要在使用的时候当作获得数据源的标志使用。
二、建立一个获得和设置上下文的类：

package cn.sunline.suncard.sde.dp.db;/** * 数据源容器类 * @author    tpf * @version   1.0  2012-8-27 * @see       [相关类/方法] * @since     [产品/模块版本]  */public class CustomerContextHolder {/** * 数据库连接配置容器 */private static ThreadLocal contextHolder = new ThreadLocal();public static void setCustomerType(String customerType) {  contextHolder.set(customerType);}     public static String getCustomerType() {  return (String) contextHolder.get();}     public static void clearCustomerType() {  contextHolder.remove();} }

这个主要负责设置上下文环境和获得上下文环境。
三、建立动态数据源类，这个类必须继承AbstractRoutingDataSource：

package cn.sunline.suncard.sde.dp.db;import org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource;/** * 动态数据源 * @author    tpf * @version   1.0  2012-8-27 * @see       [相关类/方法] * @since     [产品/模块版本]  */public class DynamicDataSource extends AbstractRoutingDataSource {/* (non-Javadoc) * @see org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource#determineCurrentLookupKey() */@Overrideprotected Object determineCurrentLookupKey() {String customerType = "";if(CustomerContextHolder.getCustomerType() != null) {customerType = CustomerContextHolder.getCustomerType().toString();}return customerType;}}

这个类实现了determineCurrentLookupKey方法，该方法返回一个Object，一般是返回字符串，也可以是枚举类型。该方法中直接使用了CustomerContextHolder.getCustomerType()方法获得上下文环境并直接返回。
四、编写spring的配置文件配置数据源

<bean id="hibernateInterceptor" class="cn.sunline.suncard.sde.dp.interceptor.HibernateInterceptor"></bean><bean id="lobHandler" class="org.springframework.jdbc.support.lob.DefaultLobHandler" lazy-init="true" /><bean id="propertyConfigurer"    class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"    dependency-check="none">    <property name="fileEncoding" value="UTF-8" />    <property name="locations">        <list>            <value>/WEB-INF/config/jdbc.properties</value>        </list>    </property></bean><!-- <bean id="acdDataSource" class="cn.sunline.suncard.sde.dp.db.ProxoolDataSourceImpl"><property name="driver"><value>${acdDataSource.driverClassName}</value></property><property name="driverUrl"><value>${acdDataSource.url}</value></property><property name="user"><value>${acdDataSource.username}</value></property><property name="password"><value>${acdDataSource.password}</value></property><property name="prototypeCount"><value>${acdDataSource.protoconn}</value></property><property name="maximumConnectionCount"><value>${acdDataSource.maxconn}</value></property><property name="minimumConnectionCount"><value>${acdDataSource.minconn}</value></property><property name="simultaneousBuildThrottle"><value>${acdDataSource.simultaneousBuildThrottle}</value></property><property name="trace"><value>false</value></property><property name="verbose"><value>true</value></property></bean><bean id="trmDataSource" class="cn.sunline.suncard.sde.dp.db.ProxoolDataSourceImpl"><property name="driver"><value>${trmDataSource.driverClassName}</value></property><property name="driverUrl"><value>${trmDataSource.url}</value></property><property name="user"><value>${trmDataSource.username}</value></property><property name="password"><value>${trmDataSource.password}</value></property><property name="prototypeCount"><value>${trmDataSource.protoconn}</value></property><property name="maximumConnectionCount"><value>${trmDataSource.maxconn}</value></property><property name="minimumConnectionCount"><value>${trmDataSource.minconn}</value></property><property name="simultaneousBuildThrottle"><value>${trmDataSource.simultaneousBuildThrottle}</value></property><property name="trace"><value>false</value></property><property name="verbose"><value>true</value></property></bean> --><bean id="acdDataSource2" class="org.springframework.jdbc.datasource.DriverManagerDataSource"><property name="driverClassName"><value>${acdDataSource.driverClassName}</value></property><property name="url"><value>${acdDataSource.url}</value></property><property name="username"><value>${acdDataSource.username}</value></property><property name="password"><value>${acdDataSource.password}</value></property></bean><bean id="trmDataSource2" class="org.springframework.jdbc.datasource.DriverManagerDataSource"><property name="driverClassName"><value>${trmDataSource.driverClassName}</value></property><property name="url"><value>${trmDataSource.url}</value></property><property name="username"><value>${trmDataSource.username}</value></property><property name="password"><value>${trmDataSource.password}</value></property></bean><bean id="dataSource" class="cn.sunline.suncard.sde.dp.db.DynamicDataSource">      <property name="targetDataSources">         <map key-type="java.lang.String">            <entry key="ACD" value-ref="acdDataSource2"/>          <entry key="TRM" value-ref="trmDataSource2"/>       </map>      </property>      <property name="defaultTargetDataSource" ref="acdDataSource2"/>   </bean><!-- sessionFactory配置开始 --><bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean"><property name="lobHandler" ref="lobHandler"/><!-- <property name="configLocation" value="/WEB-INF/config/hibernate.cfg.xml"/> --><property name="entityInterceptor">               <ref bean="hibernateInterceptor"/>          </property>        <property name="dataSource"><ref bean="dataSource" /></property><property name="hibernateProperties">   <props>    <prop key="hibernate.dialect">org.hibernate.dialect.Oracle9Dialect</prop>    <prop key="hibernate.show_sql">true</prop>    <prop key="hibernate.connection.useUnicode">true</prop>    <prop key="hibernate.connection.characterEncoding">UTF-8</prop>    <prop key="hibernate.connection.release_mode">auto</prop>   </props>  </property>  <property name="mappingResources">   <list>    <value>cn/sunline/suncard/sde/dp/hbm/DpStrategy.hbm.xml</value>    <value>cn/sunline/suncard/sde/dp/hbm/TrmUser.hbm.xml</value>    <value>cn/sunline/suncard/sde/dp/hbm/DpDatapart.hbm.xml</value>    <value>cn/sunline/suncard/sde/dp/hbm/TrmAuthtrxnlog.hbm.xml</value>   </list>  </property></bean><!--配置事务管理器  --><bean id="transactionManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager"><property name="sessionFactory"><ref bean="sessionFactory"/></property></bean><!--配置事务管理的特性(隔离级别，传播特性...)  --><tx:advice id="transAdvice" transaction-manager="transactionManager"><tx:attributes><tx:method name="find*" read-only="true"/><tx:method name="get*" read-only="true"/><tx:method name="query*" read-only="true"/><tx:method name="add*" propagation="REQUIRED" rollback-for="Exception"/><tx:method name="read*" propagation="REQUIRED" rollback-for="Exception"/><tx:method name="del*" propagation="REQUIRED" rollback-for="Exception"/><tx:method name="edit*" propagation="REQUIRED" rollback-for="Exception"/><tx:method name="save*" propagation="REQUIRED" rollback-for="Exception"/><tx:method name="update*" propagation="REQUIRED" rollback-for="Exception"/><tx:method name="insert*" propagation="REQUIRED" rollback-for="Exception"/><tx:method name="id*" propagation="REQUIRED" rollback-for="Exception"/><tx:method name="*" propagation="REQUIRED" read-only="true" rollback-for="Exception"/></tx:attributes></tx:advice><!--配置多数据源的事务拦截器-->      <aop:config><aop:pointcut expression="execution(* cn.sunline.suncard.sde.dp.dao.impl.*.*(..))" id="managerpc"/><aop:advisor advice-ref="transAdvice" pointcut-ref="managerpc"/></aop:config>

在项目中对于编码人员对多数据源的切换可以做成透明的，操作同样的dao，就可以访问不同的数据库了。