160310、oracle数据库的读写分离

PS：使用AbstractRoutingDataSource路由数据源实现动态数据库的调用

 

1、 连接哪个数据源的环境变量

package com.hysoft.common;  

public class JdbcContextHolder {

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

    

    public static void setJdbcType(String jdbcType) {

        CONTEXTHOLDER.set(jdbcType);

    }

 

    /**

     * 写读数据库

     */

    public static void setWriteDataSource() {

        setJdbcType("writeDataSource");

    }

    /**

     * 设置读数据库

     */

    public static void setReadyDataSource() {

        clearJdbcType();

    }

 

    public static String getJdbcType() {

        return (String) CONTEXTHOLDER.get();

    }

 

    public static void clearJdbcType() {

        CONTEXTHOLDER.remove();

    }

 

}

 

2、建立动态数据源类，这个类必须继承AbstractRoutingDataSource 

package com.hysoft.common;

 

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

public class DynamicDataSource extends AbstractRoutingDataSource{

 

    @Override

    protected Object determineCurrentLookupKey() {

        return JdbcContextHolder.getJdbcType();

    }

 

} 

3、配置数据库初始化xml

<?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/context 

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

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

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

 

    <!-- 数据库连接 -->

    <!-- <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">

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

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

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

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

        <property name="maxPoolSize" value="${c3p0.pool.size.max}" />

        <property name="minPoolSize" value="${c3p0.pool.size.min}" />

        <property name="initialPoolSize" value="${c3p0.pool.size.ini}" />

        <property name="acquireIncrement" value="${c3p0.pool.size.increment}" />

    </bean> -->

    

    <!-- ready only DataSource -->

    <bean id="readyDataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" destroy-method="close">  

        <property name="driverClass" value="${jdbc.ready.driverClassName}" />  

        <property name="jdbcUrl" value="${jdbc.ready.url}" />  

        <property name="user" value="${jdbc.ready.username}" />  

        <property name="password" value="${jdbc.ready.password}" />  

        <property name="maxPoolSize" value="${c3p0.pool.size.max}" />

        <property name="minPoolSize" value="${c3p0.pool.size.min}" />

        <property name="initialPoolSize" value="${c3p0.pool.size.ini}" />

        <property name="acquireIncrement" value="${c3p0.pool.size.increment}" />

    </bean>

    <!-- write only DataSource -->

    <bean id="writeDataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" destroy-method="close">  

        <property name="driverClass" value="${jdbc.write.driverClassName}" />  

        <property name="jdbcUrl" value="${jdbc.write.url}" />  

        <property name="user" value="${jdbc.write.username}" />  

        <property name="password" value="${jdbc.write.password}" />  

        <property name="maxPoolSize" value="${c3p0.pool.size.max}" />

        <property name="minPoolSize" value="${c3p0.pool.size.min}" />

        <property name="initialPoolSize" value="${c3p0.pool.size.ini}" />

        <property name="acquireIncrement" value="${c3p0.pool.size.increment}" />

    </bean>

    <!-- 动态路由数据库连接 ，默认是读数据库 -->

    <bean id="mySqlDataSource" class="com.hysoft.common.DynamicDataSource">   

        <property name="targetDataSources">   

            <map>   

                <entry key="writeDataSource" value-ref="writeDataSource"/>   

            </map>   

        </property>   

        <property name="defaultTargetDataSource" ref="readyDataSource"/>   

    </bean>

    

 

    <!-- sessionFactory 将spring和mybatis整合 -->

    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">

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

        <!-- 自动扫描xml目录,省掉手工配置 -->

        <property name="mapperLocations" value="classpath:mapping/*/*.xml" />

        <property name="plugins">

            <list>

                <ref bean="pageInterceptor" />

            </list>

        </property>

    </bean>

 

    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">

        <property name="basePackage" value="com.hysoft.*.dao"></property>

        <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"></property>

    </bean>

 

    <!-- AOP事务管理 -->

    <bean id="transactionManager"

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

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

    </bean>

 

    <!-- 注解方式配置事物 -->

    <tx:annotation-driven transaction-manager="transactionManager" />

</beans>

 

4、在serverice层指出使用的数据源

public Map<String, Object> getAllUserByPage(Map<String, Object> paramMap, String rows, String page){

        //主库 读 (默认,可以不写)

        JdbcContextHolder.setReadyDataSource();

        //辅库 写

//        JdbcContextHolder.setWriteDataSource();

        Map<String, Object> resultMap = new HashMap<String, Object>();

        PageParameter mypage = getPageMap(paramMap, Integer.valueOf(page), Integer.valueOf(rows));

        List<UserInfoDomain> rtnList = userInfoMapper.getAllUserByPage(paramMap);

        resultMap.put("total", mypage.getTotalCount());

        resultMap.put("rows", rtnList);      

        return resultMap;

    } 

 

 

/**

     * 新增数据

     * @param view

     */

    public void saveUser(UserInfoDomain domain){

        JdbcContextHolder.setWriteDataSource();

        this.userInfoMapper.insert(domain);

    }

    

    /**

     * 编辑数据

     * @param view

     */

    public void updateUser(UserInfoDomain domain){

        JdbcContextHolder.setWriteDataSource();

        this.userInfoMapper.updateByPrimaryKeySelective(domain);

}