利用spring+ibatiS技术，在spring中配置多个数据源，并实现动态切换。

 

spring中xml文件中的配置：
<bean id="dataSource1"
  class="com.mchange.v2.c3p0.ComboPooledDataSource">
  <property name="driverClass"><value>oracle.jdbc.driver.OracleDriver</value></property>

  <property name="jdbcUrl"><value>jdbc:oracle:thin:@127.0.0.1:1521:ORACLE</value></property>
  <property name="user"><value>htctposp</value></property>
  <property name="password"><value>htctposp</value></property>
  <property name="minPoolSize"><value>1</value></property>
  <property name="maxPoolSize"><value>5</value></property>
  <property name="maxIdleTime"><value>1800</value></property>
  </bean>
   <bean id="dataSource2" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="com.mysql.jdbc.Driver"></property>
        <property name="url" value="jdbc:mysql://localhost:3306/mysql?characterEncoding=UTF8"></property>
        <property name="username" value="root"></property>
        <property name="password" value="1111"></property>
    </bean>
  
    <bean id="dataSource" class="com.huateng.util.DynamicDataSource">     
         <property name="targetDataSources">  
          <map key-type="java.lang.String">     
                <entry key="dataSource1" value-ref="dataSource1"/>  
                 <entry key="dataSource2" value-ref="dataSource2"/>  
             </map>    
          </property>     
          <property name="defaultTargetDataSource" ref="dataSource1"/>     
     </bean>

 

写两个工具类DbContextHolder和DynamicDataSource，如下：
public class DynamicDataSource extends AbstractRoutingDataSource{

 static Logger log=Logger.getLogger("DynamicDataSource");
 /* (non-Javadoc)
  * @see org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource#determineCurrentLookupKey()
  */
 protected Object determineCurrentLookupKey() {
      return DbContextHolder.getDbType();
 }

}
public class DbContextHolder {
 private static final ThreadLocal contextHolder = new ThreadLocal();
 
 public static void setDbType(String dbType){
  contextHolder.set(dbType);
 }
 
 public static String getDbType(){
  return (String)contextHolder.get();
 }
 
 public static void clearDbType(){
  contextHolder.remove();
 }

}

一般在调用service层之前就要切换数据库（一般要在action中），切换数据库的代码：
 DbContextHolder.setDbType("dataSource2");