spring动态数据源配置

AbstractRoutingDataSource是spring实现的一个数据源，负责动态路由数据源的功能，我们仅需要实现determineCurrentLookupKey()方法即可

 

 

 

一，自定义DataSourceContextHolder

 

    /**

 * 
 * 数据源上下文句柄
 * <p>
 * 
 * 在dao或service层通过 {@link #set(String)} 向当前线程设置访问数据源字符串, 由DynamicDataSource类自动调用
 * 
 * @author sunflower
 * @see DynamicDataSource
 */
public class DataSourceContextHolder {
	private static final ThreadLocal<String> DS_CONTEXT = new ThreadLocal<String>();

	/**
	 * 获取当前线程的数据key 由<code>DynamicDataSource</code>类的
	 * {@link DynamicDataSource#determineCurrentLookupKey()}使用
	 * 
	 * @return
	 */
	public static String get() {
		return DS_CONTEXT.get();
	}

	/**
	 * 设置数据源key,
	 * 
	 * @param dataSourceKey
	 */
	public static void set(String dataSourceKey) {
		DS_CONTEXT.set(dataSourceKey);
	}

	/**
	 * 移除当前线程中设置的数据源key
	 */
	public static void remove() {
		DS_CONTEXT.remove();
	}

}

 

 

二，RoutingDataSource的实现

 

 

/**
 * 动态路由数据源
 * <p>
 * 
 * @author sunflower
 * 
 */
public class DynamicDataSource extends AbstractRoutingDataSource {
	/**
	 * 确定当前选择的数据源key
	 * <p>
	 * key由当前线程{@link DataSourceContextHolder#set(String)}
	 */
	@Override
	protected Object determineCurrentLookupKey() {
	
		return DataSourceContextHolder.get();
	}

}

 

 

 

 

 

三，定义dao(此略)，service

 

 

 

public class UserServiceImpl implements UserService {
	private UserDao userDao;
	
	
	public void setUserDao(UserDao userDao) {
		this.userDao = userDao;
	}


	public List<User> queryRecords(int first, int max, Map condition) {
		// 与通常单一数据源的service不一样的是，servce方法中要设置访问的数据库key,
		//其他都一样
		DataSourceContextHolder.set("nj");
		// ....condition.............
		
	}

}

 

 

 

 

四，配置spring bean 文件

 

 

 

 

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:jee="http://www.springframework.org/schema/jee"
	xmlns:tx="http://www.springframework.org/schema/tx" xmlns:util="http://www.springframework.org/schema/util"
	xmlns:context="http://www.springframework.org/schema/context"
	xmlns:aop="http://www.springframework.org/schema/aop"
	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.5.xsd http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-2.5.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-2.5.xsd http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-2.5.xsd">
	
	<bean id="userService" class="org.zkway.service.impl.UserServiceImpl">
		<property name="userDao" ref="userDao"></property>
	</bean>
	<bean id="userDao" class="org.zkway.dao.impl.UserDAOImpl">
		<property name="userDao" ref="userDao"></property>
	</bean>
	<bean id="sqlMapClient" class="org.springframework.orm.ibatis.SqlMapClientFactoryBean">
		<property name="configLocation" value="/WEB-INF/config/sql-map-config.xml" />
		<property name="dataSource" ref="dataSource" />
	</bean>
	<bean id="dataSource" class="org.zkway.common.util.db.DynamicDataSource">
		<property name="targetDataSources">
			<map>
				<entry key="nj" value-ref="njDataSource"></entry>
				<entry key="bj" value-ref="bjDataSource"></entry>
				<entry key="sz" value-ref="szDataSource"></entry>
				<entry key="sh" value-ref="njDataSource"></entry>
			</map>
		</property>
	</bean>
	<!--  数据源配置,不同数据源配置-->
	<bean id="njDataSource" class="org.logicalcobwebs.proxool.ProxoolDataSource">
		<property name="详细配置省略"></property>
	</bean>
	<bean id="shDataSource" class="org.logicalcobwebs.proxool.ProxoolDataSource">
		<property name="详细配置省略"></property>
	</bean>
	<bean id="bjDataSource" class="org.logicalcobwebs.proxool.ProxoolDataSource">
		<property name="详细配置省略"></property>
	</bean>
	<bean id="szDataSource" class="org.logicalcobwebs.proxool.ProxoolDataSource">
		<property name="详细配置省略"></property>
	</bean>
</beans>