spring的配置如下
<!-- 主数据源-->
<bean id="masterDataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="com.mysql.jdbc.Driver" />
<property name="url"
value="jdbc:mysql://127.0.0.1/test1?useUnicode=true&characterEncoding=utf8" />
<property name="username" value="root" />
<property name="password" value="123456" />
</bean>
<!-- 从数据源-->
<bean id="slaveDataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="com.mysql.jdbc.Driver" />
<property name="url"
value="jdbc:mysql://127.0.0.1/test2?useUnicode=true&characterEncoding=utf8" />
<property name="username" value="root" />
<property name="password" value="123456" />
</bean>
<bean id="dataSource" class="c.p.aop.DynamicDataSource">
<property name="targetDataSources">
<map key-type="java.lang.String">
<entry key="slave" value-ref="slaveDataSource" />
<entry key="master" value-ref="masterDataSource" />
</map>
</property>
<property name="defaultTargetDataSource" ref="masterDataSource" />
</bean>
<!-- 配置 jdbcTemplate，可通过jdbcTemplate直接操作数据库-->
<bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
<property name="dataSource" ref="dataSource" />
</bean>
<!-- 配置公共类对象 -->
<bean id="baseDao" class="cq.base.dao.impl.SSH2BaseDaoImpl">
<property name="sessionFactory" ref="sessionFactory" />
</bean>
<!-- 配置公共类对象
<bean id="pageDao" class="cq.base.dao.impl.PageDaoImpl">
<property name="sessionFactory" ref="sessionFactory" />
</bean> -->
<!-- 配置sessionFactory ，注解模式的配置-->
<bean id="sessionFactory"
class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean">
<property name="dataSource" ref="dataSource" />
<property name="packagesToScan" value="c.p.entity" />
<property name="annotatedClasses">
<list>
<value>cq.base.entity.LogBean</value>
</list>
</property>
<property name="hibernateProperties">
<props>
<!-- <prop key="hibernate.dialect">org.hibernate.dialect.Oracle10gDialect</prop> -->
<!-- <prop key="hibernate.dialect">org.hibernate.dialect.SQLServerDialect</prop>-->
<prop key="hibernate.dialect">org.hibernate.dialect.MySQLDialect</prop>
<prop key="hibernate.hbm2ddl.auto">update</prop>
<prop key="hibernate.show_sql">true</prop>
<prop key="hibernate.cache.use_second_level_cache">true</prop>
<prop key="hibernate.cache.provider_class">org.hibernate.cache.EhCacheProvider</prop>
<prop key="hibernate.cache.use_query_cache">true</prop>
</props>
</property>
</bean>
<!-- 切换数据源 -->
<bean id="dataSourceAdvice" class="c.p.aop.DataSourceAdvice"></bean>
<aop:config>
<aop:pointcut id="businessService" expression="execution(* *..*Service.*(..))" />
<aop:advisor pointcut-ref="businessService" advice-ref="dataSourceAdvice" />
</aop:config>
这里需要三个类配合
DynamicDataSource <pre name="code" class="html">DataSourceAdvice
<pre name="code" class="html">DataSourceSwitcher
c.p.aop.DynamicDataSource.java如下：
public class DynamicDataSource extends AbstractRoutingDataSource {
@Override
protected Object determineCurrentLookupKey() {
return DataSourceSwitcher.getDataSource();
}
public Logger getParentLogger() {
// TODO Auto-generated method stub
return null;
}
public <T> T unwrap(Class<T> iface,String m) throws SQLException {
// TODO Auto-generated method stub
return null;
}
public boolean isWrapperFor(Class<?> iface,String m) throws SQLException {
// TODO Auto-generated method stub
return false;
}
} c.p.aop.DataSourceAdvice.java,配置如下
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("add")
|| method.getName().startsWith("update")
|| method.getName().startsWith("delete")){
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");
}
}
<pre name="code" class="html">DataSourceSwitcher.java代码如下
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();
}
}
我们可以按照以下步骤实现
1.配置主数据库的my.ini文件，在最后面加入
#---------------------------------------------
server-id=242
log-bin=mysql-bin
relay-log=relay-bin
relay-log-index=relay-bin-index
replicate-do-db=要同步的数据库
#---------------------------------------------
重启mysql服务。
2.从数据库也配置对应的my.ini文件
#---------------------------------------------
server-id=243
log-bin=mysql-bin
relay-log=relay-bin
relay-log-index=relay-bin-index
replicate-do-db=要同步的数据库
#---------------------------------------------
重启mysql服务。
从数据库敲打以下命令
服务242上用MySQL命令行工具执行如下语句：
mysql> stop slave;
mysql> change master to master_host=‘主数据库ip‘,master_user=‘root‘,master_password=‘abcd‘;
mysql> start slave;
mysql> show slave status\G;
这样就可以实现同步的问题了。
spring hibernate配置切换数据源,实现读写分离
原文：http://blog.csdn.net/yeyincai/article/details/39472289