springboot2.1.8+sharding-jdbc3.x自定義分片

引入jar

https://start.spring.io/

<parent>
	<groupId>org.springframework.boot</groupId>
	<artifactId>spring-boot-starter-parent</artifactId>
	<version>2.1.8.RELEASE</version>
	<relativePath/> 
</parent>
  
  <dependencies>
  
    <dependency>
	<groupId>com.baomidou</groupId>
	<artifactId>mybatis-plus-boot-starter</artifactId>
	<version>3.2.0</version>
   </dependency>
  
   <dependency>
	<groupId>mysql</groupId>
	<artifactId>mysql-connector-java</artifactId>
        <version>8.0.17</version>
  </dependency>
  <dependency>
	<groupId>io.shardingsphere</groupId>
	<artifactId>sharding-jdbc-spring-boot-starter</artifactId>
	<version>3.0.0</version>
  </dependency>
  <dependency>
	<groupId>org.projectlombok</groupId>
	<artifactId>lombok</artifactId>
	<version>1.18.10</version>
	<optional>true</optional>
  </dependency>
  
  </dependencies>

添加application.properties配置

#mybatis-plus.mapper-locations=mybatis/mapper/*.xml
mybatis-plus.type-aliases-package=com.example.entity
mybatis-plus.configuration.log-impl=org.apache.ibatis.logging.stdout.StdOutImpl
spring.main.allow-bean-definition-overriding=true

#連接池爲druid時的配置
#sharding.jdbc.datasource.slave1.type=com.alibaba.druid.pool.DruidDataSource
#sharding.jdbc.datasource.slave1.url=jdbc:mysql://localhost:3306/slave1?useUnicode=true&characterEncoding=utf8&useSSL=true&allowMultiQueries=true&verifyServerCertificate=false&serverTimezone=Asia/Shanghai
#https://shardingsphere.apache.org/document/legacy/3.x/document/cn/manual/sharding-jdbc/configuration/config-spring-boot/

#數據分片 + 讀寫分離
sharding.jdbc.datasource.names=master0,master1,master0slave0,master0slave1,master1slave0,master1slave1
sharding.jdbc.config.sharding.props.sql.show=true

sharding.jdbc.datasource.master0.type=com.zaxxer.hikari.HikariDataSource
sharding.jdbc.datasource.master0.driver-class-name=com.mysql.cj.jdbc.Driver
sharding.jdbc.datasource.master0.jdbcUrl=jdbc:mysql://localhost:3306/master0?useUnicode=true&characterEncoding=utf8&useSSL=true&allowMultiQueries=true&verifyServerCertificate=false&serverTimezone=Asia/Shanghai
sharding.jdbc.datasource.master0.username=root
sharding.jdbc.datasource.master0.password=aaaa

sharding.jdbc.datasource.master0slave0.type=com.zaxxer.hikari.HikariDataSource
sharding.jdbc.datasource.master0slave0.driver-class-name=com.mysql.cj.jdbc.Driver
sharding.jdbc.datasource.master0slave0.jdbcUrl=jdbc:mysql://localhost:3306/master0slave0?useUnicode=true&characterEncoding=utf8&useSSL=true&allowMultiQueries=true&verifyServerCertificate=false&serverTimezone=Asia/Shanghai
sharding.jdbc.datasource.master0slave0.username=root
sharding.jdbc.datasource.master0slave0.password=aaaa
sharding.jdbc.datasource.master0slave1.type=com.zaxxer.hikari.HikariDataSource
sharding.jdbc.datasource.master0slave1.driver-class-name=com.mysql.cj.jdbc.Driver
sharding.jdbc.datasource.master0slave1.jdbcUrl=jdbc:mysql://localhost:3306/master0slave1?useUnicode=true&characterEncoding=utf8&useSSL=true&allowMultiQueries=true&verifyServerCertificate=false&serverTimezone=Asia/Shanghai
sharding.jdbc.datasource.master0slave1.username=root
sharding.jdbc.datasource.master0slave1.password=aaaa

sharding.jdbc.datasource.master1.type=com.zaxxer.hikari.HikariDataSource
sharding.jdbc.datasource.master1.driver-class-name=com.mysql.cj.jdbc.Driver
sharding.jdbc.datasource.master1.jdbcUrl=jdbc:mysql://localhost:3306/master1?useUnicode=true&characterEncoding=utf8&useSSL=true&allowMultiQueries=true&verifyServerCertificate=false&serverTimezone=Asia/Shanghai
sharding.jdbc.datasource.master1.username=root
sharding.jdbc.datasource.master1.password=aaaa

sharding.jdbc.datasource.master1slave0.type=com.zaxxer.hikari.HikariDataSource
sharding.jdbc.datasource.master1slave0.driver-class-name=com.mysql.cj.jdbc.Driver
sharding.jdbc.datasource.master1slave0.jdbcUrl=jdbc:mysql://localhost:3306/master1slave0?useUnicode=true&characterEncoding=utf8&useSSL=true&allowMultiQueries=true&verifyServerCertificate=false&serverTimezone=Asia/Shanghai
sharding.jdbc.datasource.master1slave0.username=root
sharding.jdbc.datasource.master1slave0.password=aaaa
sharding.jdbc.datasource.master1slave1.type=com.zaxxer.hikari.HikariDataSource
sharding.jdbc.datasource.master1slave1.driver-class-name=com.mysql.cj.jdbc.Driver
sharding.jdbc.datasource.master1slave1.jdbcUrl=jdbc:mysql://localhost:3306/master1slave1?useUnicode=true&characterEncoding=utf8&useSSL=true&allowMultiQueries=true&verifyServerCertificate=false&serverTimezone=Asia/Shanghai
sharding.jdbc.datasource.master1slave1.username=root
sharding.jdbc.datasource.master1slave1.password=aaaa

sharding.jdbc.config.sharding.tables.t_order.actual-data-nodes=ds$->{0..1}.t_order$->{0..1}
# 自定義分庫分表算法
sharding.jdbc.config.sharding.tables.t_order.databaseStrategy.complex.shardingColumns=order_id,user_id
sharding.jdbc.config.sharding.tables.t_order.databaseStrategy.complex.algorithmClassName=com.example.sharding.algorithm.DbShardingAlgorithm

## 自定義分表算法
sharding.jdbc.config.sharding.tables.t_order.tableStrategy.complex.shardingColumns=order_id,user_id
sharding.jdbc.config.sharding.tables.t_order.tableStrategy.complex.algorithmClassName=com.example.sharding.algorithm.TableShardingAlgorithm
#自增列名稱，缺省表示不使用自增主鍵生成器
sharding.jdbc.config.sharding.tables.t_order.key-generator-column-name=id

#自增列值生成器類名稱，缺省表示使用默認自增列值生成器。該類需提供無參數的構造器
#sharding.jdbc.config.sharding.tables.<logic-table-name>.key-generator-class-name=
sharding.jdbc.config.sharding.tables.t_order_item.actual-data-nodes=ds$->{0..1}.t_order_item$->{0..1}

sharding.jdbc.config.sharding.tables.t_order_item.databaseStrategy.complex.shardingColumns=order_id,user_id
sharding.jdbc.config.sharding.tables.t_order_item.databaseStrategy.complex.algorithmClassName=com.example.sharding.algorithm.DbShardingAlgorithm

## 自定義分表算法
sharding.jdbc.config.sharding.tables.t_order_item.tableStrategy.complex.shardingColumns=order_id,user_id
sharding.jdbc.config.sharding.tables.t_order_item.tableStrategy.complex.algorithmClassName=com.example.sharding.algorithm.TableShardingAlgorithm
sharding.jdbc.config.sharding.tables.t_order_item.key-generator-column-name=id

#綁定表指分片規則一致的主表和子表
sharding.jdbc.config.sharding.binding-tables[0]=t_order,t_order_item

#sharding.jdbc.config.sharding.binding-tables[1]=t_order,t_order_log
#指所有的分片數據源中都存在的表，表結構和表中的數據在每個數據庫中均完全一致。適用於數據量不大且需要與海量數據的表進行關聯查詢的場景，例如：字典表。
#sharding.jdbc.config.sharding.broadcast-tables=t_config
sharding.jdbc.config.sharding.master-slave-rules.ds0.master-data-source-name=master0
sharding.jdbc.config.sharding.master-slave-rules.ds0.slave-data-source-names=master0slave0, master0slave1
sharding.jdbc.config.sharding.master-slave-rules.ds1.master-data-source-name=master1
sharding.jdbc.config.sharding.master-slave-rules.ds1.slave-data-source-names=master1slave0, master1slave1

#https://shardingsphere.apache.org/document/legacy/3.x/document/cn/features/sharding/concept/sql/
#https://shardingsphere.apache.org/document/legacy/3.x/document/cn/manual/sharding-jdbc/configuration/config-spring-boot/
#https://www.cnblogs.com/sky-chen/p/11393659.html

自定義分片及分表算法

package com.example.sharding.algorithm;

import io.shardingsphere.api.algorithm.sharding.ListShardingValue;
import io.shardingsphere.api.algorithm.sharding.ShardingValue;
import io.shardingsphere.api.algorithm.sharding.complex.ComplexKeysShardingAlgorithm;

import java.util.*;

/**
 * https://www.cnblogs.com/sky-chen/p/11393659.html
 * 根據用戶ID和訂單號分片
 */
public class DbShardingAlgorithm implements ComplexKeysShardingAlgorithm {
    // 取模因子
    public static final Integer MODE_FACTOR = 1331;

    /**
     * Sharding.
     *
     * @param availableTargetNames available data sources or tables's names
     * @param shardingValues       sharding values
     * @return sharding results for data sources or tables's names
     */
    @Override
    public Collection<String> doSharding(Collection<String> availableTargetNames,
                                         Collection<ShardingValue> shardingValues) {
        System.err.println("--------------------DB route info begin----------------------------------");
        System.err.println(availableTargetNames);//[ds0, ds1]
        System.err.println(shardingValues);
        //[ListShardingValue(logicTableName=t_order, columnName=order_id, values=[3]), ListShardingValue(logicTableName=t_order, columnName=user_id, values=[200])]
        Set<String> shardingResults = new HashSet<>();
        Integer shardingIndex = getIndex(shardingValues) % availableTargetNames.size();
        // loop and match datasource
        for (String dbName : availableTargetNames) {
            // get logic datasource index suffix
            String nameSuffix = dbName.substring(2);
            if (nameSuffix.equals(shardingIndex.toString())) {
                shardingResults.add(dbName);
                break;
            }
        }
        System.err.println(shardingResults);
        System.err.println("--------------------DB route info end----------------------------------");
        return shardingResults;
    }

    /**
     * get datasource sharding index <p>
     * sharding algorithm : shardingIndex = (orderId + userId.hashCode()) % db.size
     *
     * @param shardingValues
     * @return
     */
    private int getIndex(Collection<ShardingValue> shardingValues) {
        int shardingIndex = 0;
        ListShardingValue<Long> listShardingValue;
        List<Long> shardingValue;
        for (ShardingValue sVal : shardingValues) {
            listShardingValue = (ListShardingValue<Long>) sVal;
            if ("order_id".equals(listShardingValue.getColumnName())) {
                shardingValue = (List<Long>) listShardingValue.getValues();
                shardingIndex += Math.abs(shardingValue.get(0)) % MODE_FACTOR;
            } else if ("user_id".equals(listShardingValue.getColumnName())) {
                shardingValue = (List<Long>) listShardingValue.getValues();
                // 這裏  % 1313 僅僅只是防止溢出
                shardingIndex += Math.abs(shardingValue.get(0).hashCode()) % MODE_FACTOR;
            }
        }
        return shardingIndex;
    }
}

package com.example.sharding.algorithm;

import io.shardingsphere.api.algorithm.sharding.ListShardingValue;
import io.shardingsphere.api.algorithm.sharding.ShardingValue;
import io.shardingsphere.api.algorithm.sharding.complex.ComplexKeysShardingAlgorithm;

import java.util.*;

/**
 * 根據用戶ID和訂單號分表
 */
public  class TableShardingAlgorithm implements ComplexKeysShardingAlgorithm {
    // 取模因子
    public static final Integer MODE_FACTOR = 1331;

    /**
     * Sharding.
     *
     * @param availableTargetNames available data sources or tables's names
     * @param shardingValues       sharding values
     * @return sharding results for data sources or tables's names
     */
    @Override
    public Collection<String> doSharding(Collection<String> availableTargetNames,
                                         Collection<ShardingValue> shardingValues) {
        System.err.println("--------------------Table route info begin----------------------------------");
        System.err.println(availableTargetNames);//[t_order0, t_order1]
        System.err.println(shardingValues);
        //[ListShardingValue(logicTableName=t_order, columnName=order_id, values=[3]), ListShardingValue(logicTableName=t_order, columnName=user_id, values=[200])]
        Set<String> shardingResults = new HashSet<>();
        Integer shardingIndex = getIndex(shardingValues) % availableTargetNames.size();
        // loop and match table
        for (String tableName : availableTargetNames) {
            String nameSuffix = tableName.substring(tableName.length()-1);
            if (nameSuffix.equals(shardingIndex.toString())) {
                shardingResults.add(tableName);
                break;
            }
        }
        System.err.println(shardingResults);
        System.err.println("--------------------Table route info end----------------------------------");
        return shardingResults;
    }
// 通過打印的sql即可看到查詢的哪個庫
    private int getIndex(Collection<ShardingValue> shardingValues) {
        int shardingIndex = 0;
        ListShardingValue<Long> listShardingValue;
        List<Long> shardingValue;
        for (ShardingValue sVal : shardingValues) {
            listShardingValue = (ListShardingValue<Long>) sVal;
            if ("order_id".equals(listShardingValue.getColumnName())) {
                shardingValue = (List<Long>) listShardingValue.getValues();
                shardingIndex += Math.abs(shardingValue.get(0)) % MODE_FACTOR;
            } else if ("user_id".equals(listShardingValue.getColumnName())) {
                shardingValue = (List<Long>) listShardingValue.getValues();
                // 這裏  % 1313 僅僅只是防止溢出
                shardingIndex += Math.abs(shardingValue.get(0).hashCode()) % MODE_FACTOR;
            }
        }
        return shardingIndex;
    }
}

創建實體類,操作邏輯

package com.example.entity;

import com.baomidou.mybatisplus.annotation.TableName;
import com.baomidou.mybatisplus.annotation.TableField;
import lombok.Data;
import java.io.Serializable;

@Data
@TableName(value = "t_order")
public class Order implements Serializable {
    private Long id;
    @TableField("order_id")
    private Long orderId;
    @TableField("user_id")
    private Long userId;
    @TableField("order_state")
    private Integer orderState;

}

package com.example.entity;

import com.baomidou.mybatisplus.annotation.TableField;
import com.baomidou.mybatisplus.annotation.TableName;
import lombok.Data;

import java.io.Serializable;

@Data
@TableName(value = "t_order_item")
public class OrderItem implements Serializable {
    private Long id;
    @TableField("order_id")
    private Long orderId;
    @TableField("user_id")
    private Long userId;
    @TableField("goods_id")
    private Integer goodsId;
    private Integer count;
    private Integer price;
}

package com.example.mapper;

import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.example.entity.Order;
import org.apache.ibatis.annotations.Mapper;

@Mapper
public interface OrderMapper extends BaseMapper<Order> {
}

package com.example.mapper;

import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.example.entity.OrderItem;
import org.apache.ibatis.annotations.Mapper;

@Mapper
public interface OrderItemMapper extends BaseMapper<OrderItem> {
}

package com.example.service;

import com.example.entity.Order;
import com.example.entity.OrderItem;

public interface IOrderService {
    /**
     * @param order 訂單
     * @param item 訂單商品
     * @return 
     */
    boolean insertOrder(Order order, OrderItem item);

    Order getById(Order order);
}

package com.example.service.impl;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.example.entity.Order;
import com.example.entity.OrderItem;
import com.example.mapper.OrderItemMapper;
import com.example.mapper.OrderMapper;
import com.example.service.IOrderService;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import javax.annotation.Resource;

@Service
public class OrderService implements IOrderService {
    @Resource
    OrderMapper orderMapper;
    @Resource
    OrderItemMapper orderItemMapper;
    @Override
    @Transactional
    public boolean insertOrder(Order order, OrderItem item) {
        orderItemMapper.insert(item);
        return orderMapper.insert(order)>0;
    }

    @Override
    public Order getById(Order order) {
        QueryWrapper<Order> query = new QueryWrapper<>(order);
        return orderMapper.selectOne(query);
    }
}

package com.example;
import com.baomidou.mybatisplus.extension.plugins.PaginationInterceptor;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.context.properties.EnableConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.transaction.annotation.EnableTransactionManagement;
//import springfox.documentation.swagger2.annotations.EnableSwagger2;

//@EnableSwagger2
@SpringBootApplication
@EnableConfigurationProperties //使 使用 @ConfigurationProperties 註解的類生效。
@EnableTransactionManagement(proxyTargetClass = true)
public class DemoApplication {

	public static void main(String[] args) {
		SpringApplication.run(DemoApplication.class, args);
	}

	@Bean
	public PaginationInterceptor paginationInterceptor() {
		return new PaginationInterceptor();
	}
}

建立數據庫及表

CREATE DATABASE if not exists master0;
-- 自行添加master1,master0slave0,master0slave1,master1slave0,master1slave1;
DROP TABLE if exists `t_order0`;
DROP TABLE if exists `t_order1`;
DROP TABLE if exists `t_order_item0`;
DROP TABLE if exists `t_order_item1`;
-- 下面的建表語句在上面的庫中分別執行一次
CREATE TABLE `t_order0` (
	`id` bigint(11) NOT NULL,
  `order_id` bigint(11) NOT NULL,
  `user_id` int(11) NOT NULL,
  `order_state` int(11) NOT NULL,
  UNIQUE KEY `orderId` (`order_id`) USING BTREE COMMENT '訂單號',
	KEY `ix_user_id` (`user_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;

CREATE TABLE `t_order1` (
	`id` bigint(11) NOT NULL,
  `order_id` bigint(11) NOT NULL,
  `user_id` int(11) NOT NULL,
  `order_state` int(11) NOT NULL,
  UNIQUE KEY `orderId` (`order_id`) USING BTREE COMMENT '訂單號',
	KEY `ix_user_id` (`user_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;

CREATE TABLE `t_order_item0` (
	`id` bigint(11) NOT NULL,
  `order_id` bigint(11) NOT NULL,
  `user_id` int(11) NOT NULL,
  `goods_id` int(11) NOT NULL,
	`count` int(11) NOT NULL,
	`price` int(11) NOT NULL,
  UNIQUE KEY `orderId` (`order_id`) USING BTREE COMMENT '訂單號',
	KEY `ix_user_id` (`user_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;

CREATE TABLE `t_order_item1` (
	`id` bigint(11) NOT NULL,
  `order_id` bigint(11) NOT NULL,
  `user_id` int(11) NOT NULL,
  `goods_id` int(11) NOT NULL,
	`count` int(11) NOT NULL,
	`price` int(11) NOT NULL,
  UNIQUE KEY `orderId` (`order_id`) USING BTREE COMMENT '訂單號',
	KEY `ix_user_id` (`user_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;

測試

package com.example.controller;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.example.entity.Order;
import com.example.entity.OrderItem;
import com.example.entity.User;
import com.example.mapper.UserMapper;
import com.example.service.DoThingService;
import com.example.service.impl.OrderService;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

import javax.annotation.Resource;
import java.util.List;

@RunWith(SpringRunner.class)
@SpringBootTest
public class DemoApplicationTests {
	@Resource
	OrderService orderService;
	@Test
	public void orderServiceTest() {
		OrderItem item = new OrderItem();
		item.setGoodsId(1);
		item.setCount(2);
		item.setPrice(12);
		item.setUserId(200L);
		item.setOrderId(3L);

		Order order = new Order();
		order.setOrderId(3L);
		order.setUserId(200L);
		order.setOrderState(0);

		orderService.insertOrder(order, item);
		System.err.println(order.getId());
	}
//數據庫主從配置未配，參照打印出來的語句來檢查是否走了自定義的路由分片
	@Test
	public void orderQueryTest() {

		Order order = new Order();
		order.setOrderId(3L);
        order.setUserId(200L);
		Order a = orderService.getById(order);
		System.err.println(a);
	}

}

---

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