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Java代码

master.jdbc.driverClassName=com.mysql.jdbc.Driver

master.jdbc.url=********

master.jdbc.username=********

master.jdbc.password=********

slave.jdbc.driverClassName=com.mysql.jdbc.Driver

slave.jdbc.url=********

slave.jdbc.username=********

slave.jdbc.password=********

Java代码

import java.lang.reflect.Method;

import org.springframework.aop.AfterReturningAdvice;

import org.springframework.aop.MethodBeforeAdvice;

import org.springframework.aop.ThrowsAdvice;

import com.company.datasource.DataSourceSwitcher;

public class DataSourceAdvice implements MethodBeforeAdvice, AfterReturningAdvice, ThrowsAdvice {

// service方法执行之前被调用

public void before(Method method, Object[] args, Object target) throws Throwable {

System.out.println(“切入点: ” + target.getClass().getName() + “类中” + method.getName() + “方法”);

if(method.getName().startsWith(“add”)

|| method.getName().startsWith(“create”)

|| method.getName().startsWith(“save”)

|| method.getName().startsWith(“edit”)

|| method.getName().startsWith(“update”)

|| method.getName().startsWith(“delete”)

|| method.getName().startsWith(“remove”)){

System.out.println(“切换到: master”);

DataSourceSwitcher.setMaster();

}

else  {

System.out.println(“切换到: slave”);

DataSourceSwitcher.setSlave();

}

}

// service方法执行完之后被调用

public void afterReturning(Object arg0, Method method, Object[] args, Object target) throws Throwable {

}

// 抛出Exception之后被调用

public void afterThrowing(Method method, Object[] args, Object target, Exception ex) throws Throwable {

DataSourceSwitcher.setSlave();

System.out.println(“出现异常,切换到: slave”);

}

}

Java代码

package com.company.datasource;

import org.springframework.util.Assert;

public class DataSourceSwitcher {

@SuppressWarnings(“rawtypes”)

private static final ThreadLocal contextHolder = new ThreadLocal();

@SuppressWarnings(“unchecked”)

public static void setDataSource(String dataSource) {

Assert.notNull(dataSource, “dataSource cannot be null”);

contextHolder.set(dataSource);

}

public static void setMaster(){

clearDataSource();

}

public static void setSlave() {

setDataSource(“slave”);

}

public static String getDataSource() {

return (String) contextHolder.get();

}

public static void clearDataSource() {

contextHolder.remove();

}

}

Java代码

package com.company.datasource;

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

public class DynamicDataSource extends AbstractRoutingDataSource {

@Override

protected Object determineCurrentLookupKey() {

return DataSourceSwitcher.getDataSource();

}

}

Xml代码

<?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:aop=”http://www.springframework.org/schema/aop”

xmlns:tx=”http://www.springframework.org/schema/tx” xmlns:context=”http://www.springframework.org/schema/context”

xsi:schemaLocation=”

http://www.springframework.org/schema/beans

http://www.springframework.org/schema/beans/spring-beans-3.0.xsd

http://www.springframework.org/schema/tx

http://www.springframework.org/schema/tx/spring-tx-3.0.xsd

http://www.springframework.org/schema/aop

http://www.springframework.org/schema/aop/spring-aop-3.0.xsd

http://www.springframework.org/schema/context

http://www.springframework.org/schema/context/spring-context-3.0.xsd”>

<context:annotation-config />

<!– 自动加载SERVICE DAO ACTION –>

<context:component-scan base-package=”cn.com.company.dao.*” />

<context:component-scan base-package=”cn.com.company.service.*” />

<context:component-scan base-package=”cn.com.company.action” />

<!– 加载properties配置文件 –>

<bean id=”propertyConfigurer”

class=”org.springframework.beans.factory.config.PropertyPlaceholderConfigurer”>

<property name=”locations”>

<list>

<value>classpath:jdbc.properties</value>

</list>

</property>

</bean>

<bean id=”parentDataSource” class=”com.mchange.v2.c3p0.ComboPooledDataSource”>

//***c3p0配置

</bean>

<!– 主数据源–>

<bean id=”masterDataSource” parent=”parentDataSource”>

<property name=”driverClass” value=”${master.jdbc.driverClassName}” />

<property name=”jdbcUrl” value=”${master.jdbc.url}” />

<property name=”user” value=”${master.jdbc.username}” />

<property name=”password” value=”${master.jdbc.password}” />

</bean>

<!– 从数据源–>

<bean id=”slaveDataSource” parent=”parentDataSource”>

<property name=”driverClass” value=”${slave.jdbc.driverClassName}” />

<property name=”jdbcUrl” value=”${slave.jdbc.url}” />

<property name=”user” value=”${slave.jdbc.username}” />

<property name=”password” value=”${slave.jdbc.password}” />

</bean>

<bean id=”dataSource” class=”com.company.datasource.DynamicDataSource”>

<property name=”targetDataSources”>

<map key-type=”java.lang.String”>

<entry key=”slave” value-ref=”slaveDataSource” />

</map>

</property>

<property name=”defaultTargetDataSource” ref=”masterDataSource” />

</bean>

<!– 配置sessionFactory –>

<bean id=”sessionFactory”

class=”org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean”>

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

<property name=”packagesToScan” value=”cn.com.company.entity” />

<property name=”hibernateProperties”>

<props>

<prop>//***hibernate一些参数这里不写了</prop>

</props>

</property>

</bean>

<!– 切换数据源 –>

<bean id=”dataSourceAdvice” class=”com.company.aop.DataSourceAdvice” />

<aop:config>

<aop:advisor

pointcut=”execution(* cn.com.company.service..*Service.*(..))”

advice-ref=”dataSourceAdvice” />

</aop:config>

<!– 配置事务管理器 –>

<bean id=”transactionManager”

class=”org.springframework.orm.hibernate3.HibernateTransactionManager”>

<property name=”sessionFactory”>

<ref bean=”sessionFactory” />

</property>

</bean>

<!–配置事务的传播特性 –>

<tx:advice id=”txAdvice” transaction-manager=”transactionManager”>

<tx:attributes>

<!– 对增、删、改方法进行事务支持 –>

<tx:method name=”add*” propagation=”REQUIRED” />

<tx:method name=”create*” propagation=”REQUIRED” />

<tx:method name=”save*” propagation=”REQUIRED” />

<tx:method name=”edit*” propagation=”REQUIRED” />

<tx:method name=”update*” propagation=”REQUIRED” />

<tx:method name=”delete*” propagation=”REQUIRED” />

<tx:method name=”remove*” propagation=”REQUIRED” />

<!– 对查找方法进行只读事务 –>

<tx:method name=”loadByUsername*” propagation=”SUPPORTS” read-only=”true” />

<!– 对其它方法进行只读事务 –>

<tx:method name=”*” propagation=”SUPPORTS” read-only=”true” />

</tx:attributes>

</tx:advice>

<!–那些类的哪些方法参与事务 –>

<aop:config>

<aop:advisor

pointcut=”execution(* cn.com.company.service..*Service.*(..))”

advice-ref=”txAdvice” />

<aop:advisor

pointcut=”execution(* cn.com.company.service..*ServiceImpl.*(..))”

advice-ref=”txAdvice” />

</aop:config>

</beans>