import java.sql.SQLFeatureNotSupportedException;

import java.util.Map;

import com.alibaba.druid.pool.DruidDataSource;

import org.apache.log4j.Logger;

import org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource;

import com.xyh.util.SpringUtils;

/**

 * @author yuanhao

 * @describe 实现动态数据源切换逻辑

 */

public  class DataSourceUtil extends AbstractRoutingDataSource {

private Logger log = Logger.getLogger(this.getClass());

/**

 * 数据源资源池

 */

private Map<Object, Object> _targetDataSources;

/**

 * 数据源名称

 */

/**

 * @see org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource#determineCurrentLookupKey()

 * @describe 数据源为空或者为0时，自动切换至默认数据源

 */

@Override

protected Object determineCurrentLookupKey() {

    String dataSourceName = DBContextHolder.getDataSource();

    try {

        if (dataSourceName == null || "".equals(dataSourceName)) {// 如果传入数据源id为空

            throw new Exception("传入的数据源名称为空，无法选择数据源");

        }

        this.selectDataSource(dataSourceName);

    } catch (Exception e) {

        e.printStackTrace();

    }

    log.debug("--------> use datasource " + dataSourceName);

    return dataSourceName;

}

/**

 * @param key

 *           数据源id

 * @throws Exception

 * @describe 数据源存在连接池中时不做处理， 不存在将新数据链接添加至连接池

 * /

public void selectDataSource(String dataSourceName) throws Exception {

    Object obj = this._targetDataSources.get(dataSourceName);

    // 如果数据源已经有了

    if (obj != null) {

        return;

    } else {// 如果没有则从spring容器中获取

        DruidDataSource dataSource = (DruidDataSource) SpringUtils

                .getBeanInstance(dataSourceName);

        if (dataSource != null)

            this.setDataSource(dataSourceName, dataSource);

        else {

            throw new Exception("无法取得数据库连接配置，请核对是否已经配置");

        }

    }

}

/**

 * 将数据源写入池中

 * @param key

 * @param dataSource

 */

private void setDataSource(String dataSourceName, DruidDataSource dataSource) {

    //this.addTargetDataSource(dataSourceName, dataSource);

    this._targetDataSources.put(dataSourceName, dataSource);

    this.setTargetDataSources(this._targetDataSources);

}

@SuppressWarnings({ "unchecked", "rawtypes" })

public void setTargetDataSources(Map targetDataSources) {

    this._targetDataSources = targetDataSources;

    super.setTargetDataSources(this._targetDataSources);

    afterPropertiesSet();

}

/*

public void addTargetDataSource(String key, DruidDataSource dataSource) {

}*/

/**

 * @return

 * @throws SQLFeatureNotSupportedException

 */

public java.util.logging.Logger getParentLogger()

        throws SQLFeatureNotSupportedException {

    // TODO Auto-generated method stub

    return null;

    }

}

public class DBContextHolder {

private static final ThreadLocal<String> contextHolder = new ThreadLocal<String>();

/**

 * 传入数据源名称

 *

 * @param key

 */

public static void setDataSource(String key) {

    contextHolder.set(key);

}

/**

 * 取数据源名称

 *

 * @return

 */

public static String getDataSource() {

    return contextHolder.get();

}

/**

 * 销毁数据源名称

 *

 * @return

 */

public static void clearDataSource() {

    contextHolder.remove();

}

}

<!--db1-->

<bean id="dataSource411602" class="com.alibaba.druid.pool.DruidDataSource"

    destroy-method="close" lazy-init="true">

    <property name="driverClassName">

        <value>${jdbc.oracle.driverClassName}</value>

    </property>

    <property name="url">

        <value>jdbc:oracle:thin:@192.168.0.1:20003:orcl</value>

    </property>

    <property name="username">

        <value>test</value>

    </property>

    <property name="password">

        <value>test</value>

    </property>

    <property name="filters" value="stat"></property>

</bean>

<!--db2-->

<bean id="dataSource411606" class="com.alibaba.druid.pool.DruidDataSource"

    destroy-method="close" lazy-init="true">

    <property name="driverClassName">

        <value>${jdbc.oracle.driverClassName}</value>

    </property>

    <property name="url">

        <value>jdbc:oracle:thin:@192.168.0.2:60021:orcl</value>

    </property>

    <property name="username">

        <value>test</value>

    </property>

    <property name="password">

        <value>test</value>

    </property>

    <property name="filters" value="stat"></property>

</bean>

<!--数据源-->

<bean id="dataSource" class="com.xyh.util.dbutil.DataSourceUtil">

    <property name="targetDataSources">

        <map key-type="java.lang.String">

        </map>

    </property>

</bean>

    <bean id="sqlMapClient" class="org.springframework.orm.ibatis.SqlMapClientFactoryBean">

    <property name="configLocations">

        <list>

            <value>classpath:sql-map-config.xml</value>

        </list>

    </property>

    <property name="dataSource" ref="dataSource" />

</bean>

<!-- JDBC 事务管理 -->

<bean id="jdbcTxManager"

    class="org.springframework.jdbc.datasource.DataSourceTransactionManager">

    <property name="dataSource">

        <ref bean="dataSource" />

    </property>

</bean>