Sharding-JDBC 使用入门和基本配置

<!-- sharding jdbc 开始-->
<dependency>
    <groupId>io.shardingsphere</groupId>
    <artifactId>sharding-core</artifactId>
    <version>${sharding.version}</version>
</dependency>
<dependency>
    <groupId>io.shardingsphere</groupId>
    <artifactId>sharding-jdbc-spring-namespace</artifactId>
    <version>${sharding.version}</version>
</dependency>
<!—如果不配置分布式事务的话配置上边两个就够了 --> 
<!--分布式事务引用依赖-->
<dependency>
    <groupId>io.shardingsphere</groupId>
    <artifactId>sharding-transaction-2pc-xa</artifactId>
    <version>${sharding.version}</version>
</dependency>
<dependency>
    <groupId>io.shardingsphere</groupId>
    <artifactId>sharding-transaction-spring</artifactId>
    <version>${sharding.version}</version>
</dependency>
<!-- sharding jdbc 结束-->
<!--AspectJ AOP支持 -->
<dependency>
    <groupId>org.aspectj</groupId>
    <artifactId>aspectjweaver</artifactId>
    <version>${aspectjweaver.version}</version>
</dependency>

<!-- ds0的主-->
<bean id="ds0_master" class="com.alibaba.druid.pool.DruidDataSource" destroy-method="close" parent="parentDs"> 
<property name="driverClassName" value=""/>
    <property name="url" value=""/>
</bean>
<!-- ds0的从-->
<bean id="ds0_slave" class="com.alibaba.druid.pool.DruidDataSource" destroy-method="close" parent="parentDs">
    <property name="driverClassName" value=""/>
    <property name="url" value="${sharding.connection.url.0}"/>
</bean>
<!-- ds1的主-->
<bean id="ds1_master" class="com.alibaba.druid.pool.DruidDataSource" destroy-method="close" parent="parentDs">
    <property name="driverClassName" value=""/>
    <property name="url" value="${sharding.connection.url.1}"/>
</bean>
<!-- ds1的从-->
<bean id="ds1_slave" class="com.alibaba.druid.pool.DruidDataSource" destroy-method="close" parent="parentDs">
    <property name="driverClassName" value=""/>
    <property name="url" value="${sharding.connection.url.1}"/>
</bean>

<master-slave:data-source id="masterSlaveDataSource" master-data-source-name="ds0_master, ds1_master" slave-data-source-names="ds0_slave, ds1_slave " >
        <master-slave:props>
                <prop key="sql.show">${sql_show}</prop>
                <prop key="executor.size">10</prop>
                <prop key="foo">bar</prop>
        </master-slave:props>
</master-slave:data-source>

<!-- sharding数据源-->
<sharding:data-source id="shardingDataSource">
    <!-- 读写分离的话要把所有的主从数据源都写在这里-->
    <sharding:sharding-rule
            data-source-names="ds0_master,ds0_slave,ds1_master,ds1_slave ">
        <!-- 读写分离的路由 一主一从配置 strategy-ref  -->
        <sharding:master-slave-rules>
            <sharding:master-slave-rule id="ds0" master-data-source-name="ds0_master"                                        slave-data-source-names="ds0_slave"/>
            <sharding:master-slave-rule id="ds1" master-data-source-name="ds1_master"                                        slave-data-source-names="ds1_slave"/>
        </sharding:master-slave-rules>
        <!-- 读写分离配置 结束-->
        <sharding:table-rules>
    <!— 这里是分库分表路由的配置 -->
        </sharding:table-rules>
        <sharding:binding-table-rules>
    <!—- 绑定表的配置 --> 
        </sharding:binding-table-rules>
 </sharding:sharding-rule>
<sharding:props>
        <!-- 显示SQL -->
        <prop key="sql.show">true</prop>
    </sharding:props>
</sharding:data-source>

<!-- 标准分片策略。-->
<bean id="demoUserStandardStrategy" class="shard.strategy.DemoUserStandardStrategy"/>
<sharding:standard-strategy id="shardingDemoUserStandardStrategy"
                            precise-algorithm-ref="demoUserStandardStrategy" sharding-column="id"                            range-algorithm-ref=""/>

/**
 * 根据ID取
 * 标准分片策略
 * 用于处理=和IN的分片
 * @author yulonggao
 * @date 2019/1/31 14:35
 */
@Slf4j
public class DemoUserStandardStrategy implements PreciseShardingAlgorithm<Long> {
    @Override
    public String doSharding(Collection<String> collection, PreciseShardingValue<Long> preciseShardingValue) {
        //这个里边有异常会被处理掉，然后导致拿不到分片。但出异常一般是业务代码写错了。
        //每条指定分片的操作都会调用此方法，如果是in 条件查询的话每个值会调用一次此方法，如果是批量插入也是每一条都要调用一次进行分片
        log.info("DemoUserStandardStrategy_preciseShardingValue={}", preciseShardingValue);
        Long suffix = preciseShardingValue.getValue() % 4;
        log.info("suffix={}", suffix);
        final String targetDb = String.valueOf(Math.abs(suffix.intValue()));
        String shardingValue = collection.stream().filter(p -> p.endsWith(targetDb)).findFirst().get();
        log.info("preciseShardingValue={},shardingValue={}", preciseShardingValue, shardingValue);
        return shardingValue;
    }

<!-- 强制路由分片策略-->
<bean id="demoUserHintStrategy" class="shard.strategy.DemoUserHintStrategy"/>
<!-- 强制路由例子使用-->
<sharding:hint-strategy id="shardingDemoUserHintStrategy" algorithm-ref="demoUserHintStrategy"/>
DemoUserHintStrategy 的Java 如下，强制分片要实现HintShardingAlgorithm接口。
/**
 * DemoUserHint强制路由分片策略,其实可以共用，只是例子
 * @author yulonggao
 * @date 2019/1/31 14:35
 */
@Slf4j
public class DemoUserHintStrategy implements HintShardingAlgorithm {
    @Override
    public Collection<String> doSharding(Collection<String> availableTargetNames, ShardingValue shardingValue) {
        //availableTargetNames 这个参数是所有的dataSource的集合，shardingValue是HintManager传过来的分片信息
        log.info("DemoUserHintStrategy_availableTargetNames={}", availableTargetNames);
        log.info("DemoUserHintStrategy_shardingValue={}", shardingValue);
        ListShardingValue listShardingValue = (ListShardingValue) shardingValue;
        Collection shardingValueList = listShardingValue.getValues();
        //因为调用的时候分片是直接传的 DataSource的名称，所以直接返回就可以了，如果传其它值则要加业务逻辑进行分片筛选
        //返回结果只能是availableTargetNames 里边所包含的
        return shardingValueList;
    }
}

<!—主键生成 -->
<bean id="keyId" class="shard.key.DefaultKeyGenerator"/>

<bean id="transactionManager"
      class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
    <property name="dataSource" ref="shardingDataSource"></property>
</bean>
<tx:annotation-driven transaction-manager="transactionManager"/>
<!-- 事务支持-->
<import resource="classpath:META-INF/shardingTransaction.xml"/>

/**
 * 注意：@ShardingTransactionType需要同Spring的@Transactional配套使用，事务才会生效。
 * @param param
 * @return
 */
@ShardingTransactionType(TransactionType.XA)
@Transactional(rollbackFor = Exception.class)
@Override
public int addParam(DemoParam param) {
log.info("addParam-param={}", param);
return demoParamDao.addParam(param);
}