shadingjdbc实战分表分库

一、问题汇总

1. 水平与垂直拆分之间的区别？

垂直拆分：根据业务实现拆分

微服务架构模式中，会员团队、支付团队、交易团队。有自己独立的数据库，会员db、支付db、交易db，带来的分布式事务问题。

水平拆分：将一张大表的数量拆分n多张不同子表。

• 第1种：同一库分表

原表：mayikt-member–1500万条

分表：

mayikt-member0–0~500万条

mayikt-member1–500~1000万条

mayikt-member2–1000~1500万条

• 第2种：多库分表

原表：mayikt-member–1500万条

mayikt-member：

分库分表：

mayikt-memberdb01

mayikt-member --0~500万条

mayikt-memberdb02

mayikt-member --500~1000万条

mayikt-memberdb03

mayikt-member --1000~1500万条

2. 单表达到多大量开始进行分库分表？

单表行数超过500万行或者单标容量超过2GB，才推荐进行分库分表。

说明：如果预计三年后的数据量根据达不到这个级别，请不要在创建表时就分库分表。

3. 基于客户端与服务端实现分表分库区别？

• 1.基于服务端mycat实现数据库代理
  优点：能够保证数据库的安全性
  缺点：效率比较低

• 2.基于客户端SHardingjdbc实现数据库代理
  有点：效率比较高
  缺点：不能够保证数据库的安全性，内存溢出

4. 数据库分表分库策略有哪些？

区域/取模（不推荐使用，后期无法进行扩容）
按照范围分片（推荐使用）
按照日期进行分片
按照枚举进行分片
一致性hash分片
按照目标字段前缀制定进行分片

5. 自定义范围分表算法实现分表?

package com.mayikt.api.impl.config;

import io.shardingsphere.api.algorithm.sharding.PreciseShardingValue;
import io.shardingsphere.api.algorithm.sharding.standard.PreciseShardingAlgorithm;
import lombok.extern.slf4j.Slf4j;

import java.util.Collection;

@Slf4j
public class MayiktPreciseShardingAlgorithm implements PreciseShardingAlgorithm<Long> {
    
    
    /**
     * 真实建议是为500万测试为5条
     */
    private Long tableSize = 5l;

    /**
     * 插入数据 改写表的名称
     * 查询 改写表的名称
     * @param collection
     * @param preciseShardingValue
     * @return
     */
    @Override
    public String doSharding(Collection<String> collection, PreciseShardingValue<Long> preciseShardingValue) {
    
    
        Double userId = Double.valueOf(preciseShardingValue.getValue());
        Double temp = userId / tableSize;
        String tableName = "meite_user" + (int) Math.ceil(temp);
        // 分表分库 userid====mysql自带的自增 序列 雪花算法
        log.info("<tableName{}>", tableName);
        return tableName;
    }
}

二、整合ShardingSphere实现分表

2.1. 依赖

        <!--分表库分表中间件-->
        <dependency>
            <groupId>io.shardingsphere</groupId>
            <artifactId>sharding-jdbc-spring-boot-starter</artifactId>
            <version>3.1.0</version>
        </dependency>
        <dependency>
            <groupId>io.shardingsphere</groupId>
            <artifactId>sharding-jdbc-spring-namespace</artifactId>
            <version>3.1.0</version>
        </dependency>

2.2. 配置

spring:
  jackson:
    date-format: yyyy-MM-dd HH:mm:ss
  profiles:
    active: dev
  application:
    ###服务的名称
    name: mayikt-member
  cloud:
    nacos:
      discovery:
        ###nacos注册地址
        server-addr: 127.0.0.1:8848
      config:
        server-addr: 127.0.0.1:8848
        file-extension: yml
  #  datasource:
  #    driver-class-name: com.mysql.cj.jdbc.Driver
  #    url: jdbc:mysql://localhost:3306/mayikt-member?useUnicode=true&characterEncoding=UTF-8&serverTimezone=GMT%2B8
  #    username: root
  #    password: 123456
  redis:
    host: 127.0.0.1
    port: 6379
    password: 123456
  logging:
    level:
      ###打印mybatis日志
      com.mayikt.api.impl.mapper: debug
  main:
    allow-bean-definition-overriding: true
server:
  port: 7000
mayikt:
  userName: mayikt
  thread:
    corePoolSize: 10
    maxPoolSize: 10
    queueCapacity: 20
    keepAlive: 60

# 数据源 mayiktdb
#按照范围分片
sharding:
  jdbc:
    datasource:
      names: mayikt-member
      # 第一个数据库
      mayikt-member:
        type: com.zaxxer.hikari.HikariDataSource
        driver-class-name: com.mysql.cj.jdbc.Driver
        jdbc-url: jdbc:mysql://127.0.0.1:3306/mayikt-member?useUnicode=true&characterEncoding=UTF-8&serverTimezone=GMT%2B8
        username: root
        password: 123456
    # 水平拆分的数据库（表） 配置分库 + 分表策略 行表达式分片策略
    config:
      sharding:
        tables:
          meite_user:
            actual-data-nodes: mayikt-member.meite_user$->{
    
    1..3}
            table-strategy:
              standard:
                ### where userId
                precise-algorithm-class-name: com.mayikt.api.impl.config.MayiktPreciseShardingAlgorithm
                sharding-column: user_id
      # 打印执行的数据库
      props:
        sql:
          show: true
# 取模配置
## 数据源 mayiktdb
#sharding:
#  jdbc:
#    datasource:
#      names: mayikt-member
#      # 第一个数据库
#      mayikt-member:
#        type: com.zaxxer.hikari.HikariDataSource
#        driver-class-name: com.mysql.cj.jdbc.Driver
#        jdbc-url: jdbc:mysql://127.0.0.1:3306/mayikt-member?useUnicode=true&characterEncoding=UTF-8&serverTimezone=GMT%2B8
#        username: root
#        password: 123456
#    # 水平拆分的数据库（表） 配置分库 + 分表策略 行表达式分片策略
#    config:
#      sharding:
#        tables:
#          meite_user:
#            # mayikt-member.meite_user0 mayikt-member.meite_user1 mayikt-member.meite_user2
#            actual-data-nodes: mayikt-member.meite_user$->{0..2}
#            table-strategy:
#              inline:
#                # 根据user_id分表
#                sharding-column: user_id
#                # 分片算法表达式 meite_user——1%3 meite_user_2% 3  meite_user_3% 3
#                algorithm-expression: meite_user$->{user_id % 3}
#      # 打印执行的数据库
#      props:
#        sql:
#          show: true

2.3. 表结构

SET NAMES utf8mb4;
SET FOREIGN_KEY_CHECKS = 0;

-- ----------------------------
-- Table structure for meite_user
-- ----------------------------
DROP TABLE IF EXISTS `meite_user`;
CREATE TABLE `meite_user`  (
  `USER_ID` int NOT NULL AUTO_INCREMENT COMMENT 'USER_ID',
  `MOBILE` varchar(11) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '手机号',
  `PASSWORD` varchar(64) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '密码',
  `USER_NAME` varchar(50) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '用户名',
  `SEX` tinyint(1) NULL DEFAULT 0 COMMENT '性别 1-男 2-女',
  `AGE` tinyint NULL DEFAULT 0 COMMENT '年龄',
  `CREATE_TIME` timestamp NULL DEFAULT NULL COMMENT '注册时间',
  `IS_AVALIBLE` tinyint(1) NULL DEFAULT 1 COMMENT '是否可用 1-正常 2-冻结 ',
  `PIC_IMG` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '用户头像',
  `QQ_OPEN_ID` varchar(50) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT 'QQ联合登陆id',
  `WX_OPEN_ID` varchar(50) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '微信公众号关注id',
  `VERSION` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,
  `IS_DELETE` int NULL DEFAULT NULL,
  PRIMARY KEY (`USER_ID`) USING BTREE,
  UNIQUE INDEX `MOBILE_UNIQUE`(`MOBILE`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 87 CHARACTER SET = utf8 COLLATE = utf8_general_ci COMMENT = '用户会员表' ROW_FORMAT = Dynamic;

-- ----------------------------
-- Records of meite_user
-- ----------------------------
INSERT INTO `meite_user` VALUES (21, '17610155217', '15A013BCAC0C50049356B322E955035E', '90架构师', 0, 0, NULL, 1, NULL, NULL, 'oD8nF5jpNF9KXU_j49uvqOPVdiEU', NULL, 0);

-- ----------------------------
-- Table structure for meite_user0
-- ----------------------------
DROP TABLE IF EXISTS `meite_user0`;
CREATE TABLE `meite_user0`  (
  `USER_ID` int NOT NULL AUTO_INCREMENT COMMENT 'USER_ID',
  `MOBILE` varchar(11) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '手机号',
  `PASSWORD` varchar(64) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '密码',
  `USER_NAME` varchar(50) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '用户名',
  `SEX` tinyint(1) NULL DEFAULT 0 COMMENT '性别 1-男 2-女',
  `AGE` tinyint NULL DEFAULT 0 COMMENT '年龄',
  `CREATE_TIME` timestamp NULL DEFAULT NULL COMMENT '注册时间',
  `IS_AVALIBLE` tinyint(1) NULL DEFAULT 1 COMMENT '是否可用 1-正常 2-冻结 ',
  `PIC_IMG` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '用户头像',
  `QQ_OPEN_ID` varchar(50) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT 'QQ联合登陆id',
  `WX_OPEN_ID` varchar(50) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '微信公众号关注id',
  `VERSION` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,
  `IS_DELETE` int NULL DEFAULT NULL,
  PRIMARY KEY (`USER_ID`) USING BTREE,
  UNIQUE INDEX `MOBILE_UNIQUE`(`MOBILE`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 87 CHARACTER SET = utf8 COLLATE = utf8_general_ci COMMENT = '用户会员表' ROW_FORMAT = Dynamic;

-- ----------------------------
-- Records of meite_user0
-- ----------------------------
INSERT INTO `meite_user0` VALUES (12, '17610155217', '15A013BCAC0C50049356B322E955035E', '90架构师12', 0, 0, NULL, 1, NULL, NULL, 'oD8nF5jpNF9KXU_j49uvqOPVdiEU', NULL, 0);

-- ----------------------------
-- Table structure for meite_user1
-- ----------------------------
DROP TABLE IF EXISTS `meite_user1`;
CREATE TABLE `meite_user1`  (
  `USER_ID` int NOT NULL AUTO_INCREMENT COMMENT 'USER_ID',
  `MOBILE` varchar(11) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '手机号',
  `PASSWORD` varchar(64) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '密码',
  `USER_NAME` varchar(50) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '用户名',
  `SEX` tinyint(1) NULL DEFAULT 0 COMMENT '性别 1-男 2-女',
  `AGE` tinyint NULL DEFAULT 0 COMMENT '年龄',
  `CREATE_TIME` timestamp NULL DEFAULT NULL COMMENT '注册时间',
  `IS_AVALIBLE` tinyint(1) NULL DEFAULT 1 COMMENT '是否可用 1-正常 2-冻结 ',
  `PIC_IMG` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '用户头像',
  `QQ_OPEN_ID` varchar(50) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT 'QQ联合登陆id',
  `WX_OPEN_ID` varchar(50) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '微信公众号关注id',
  `VERSION` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,
  `IS_DELETE` int NULL DEFAULT NULL,
  PRIMARY KEY (`USER_ID`) USING BTREE,
  UNIQUE INDEX `MOBILE_UNIQUE`(`MOBILE`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 87 CHARACTER SET = utf8 COLLATE = utf8_general_ci COMMENT = '用户会员表' ROW_FORMAT = Dynamic;

-- ----------------------------
-- Records of meite_user1
-- ----------------------------

-- ----------------------------
-- Table structure for meite_user2
-- ----------------------------
DROP TABLE IF EXISTS `meite_user2`;
CREATE TABLE `meite_user2`  (
  `USER_ID` int NOT NULL COMMENT 'USER_ID',
  `MOBILE` varchar(11) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '手机号',
  `PASSWORD` varchar(64) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '密码',
  `USER_NAME` varchar(50) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '用户名',
  `SEX` tinyint(1) NULL DEFAULT 0 COMMENT '性别 1-男 2-女',
  `AGE` tinyint NULL DEFAULT 0 COMMENT '年龄',
  `CREATE_TIME` timestamp NULL DEFAULT NULL COMMENT '注册时间',
  `IS_AVALIBLE` tinyint(1) NULL DEFAULT 1 COMMENT '是否可用 1-正常 2-冻结 ',
  `PIC_IMG` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '用户头像',
  `QQ_OPEN_ID` varchar(50) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT 'QQ联合登陆id',
  `WX_OPEN_ID` varchar(50) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '微信公众号关注id',
  `VERSION` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,
  `IS_DELETE` int NULL DEFAULT NULL,
  PRIMARY KEY (`USER_ID`) USING BTREE,
  UNIQUE INDEX `MOBILE_UNIQUE`(`MOBILE`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 87 CHARACTER SET = utf8 COLLATE = utf8_general_ci COMMENT = '用户会员表' ROW_FORMAT = Dynamic;

-- ----------------------------
-- Records of meite_user2
-- ----------------------------
INSERT INTO `meite_user2` VALUES (6, '17610135255', NULL, '90架构师update', 1, 2, '2014-09-05 18:54:16', 1, 'test_45904720d2ea', NULL, NULL, NULL, 0);

-- ----------------------------
-- Table structure for meite_user3
-- ----------------------------
DROP TABLE IF EXISTS `meite_user3`;
CREATE TABLE `meite_user3`  (
  `USER_ID` int NOT NULL AUTO_INCREMENT COMMENT 'USER_ID',
  `MOBILE` varchar(11) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '手机号',
  `PASSWORD` varchar(64) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '密码',
  `USER_NAME` varchar(50) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '用户名',
  `SEX` tinyint(1) NULL DEFAULT 0 COMMENT '性别 1-男 2-女',
  `AGE` tinyint NULL DEFAULT 0 COMMENT '年龄',
  `CREATE_TIME` timestamp NULL DEFAULT NULL COMMENT '注册时间',
  `IS_AVALIBLE` tinyint(1) NULL DEFAULT 1 COMMENT '是否可用 1-正常 2-冻结 ',
  `PIC_IMG` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '用户头像',
  `QQ_OPEN_ID` varchar(50) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT 'QQ联合登陆id',
  `WX_OPEN_ID` varchar(50) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '微信公众号关注id',
  `VERSION` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,
  `IS_DELETE` int NULL DEFAULT NULL,
  PRIMARY KEY (`USER_ID`) USING BTREE,
  UNIQUE INDEX `MOBILE_UNIQUE`(`MOBILE`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 87 CHARACTER SET = utf8 COLLATE = utf8_general_ci COMMENT = '用户会员表' ROW_FORMAT = Dynamic;

2.4. 测试接口

package com.mayikt.api.member;

import com.mayikt.api.base.BaseResponse;
import com.mayikt.api.member.dto.resp.UserInfoDto;
import org.springframework.web.bind.annotation.*;

public interface UserInfoService {
    
    

    /**
     * 根据token获取用户的信息
     *
     * @param token
     * @return
     */
    @GetMapping("getUserInfo")
    BaseResponse<UserInfoDto> getUserInfo(@RequestParam("token") String token);

    // 分库分表案例接口

    /**
     * 测试根据用户userId查询分表用户数据
     *
     * @param userId
     * @return
     */
    @GetMapping("testGetSubTableUser")
    BaseResponse<UserInfoDto> testGetSubTableUser(Long userId);

    /**
     * 测试根据用户userId删除分表用户数据
     *
     * @param userId
     * @return
     */
    @DeleteMapping("testDelSubTableUser")
    BaseResponse<String> testDelSubTableUser(Long userId);

    /**
     * 测试增加用户数据到分表中
     *
     * @param userReqDto
     * @return
     */
    @PostMapping("testInsertSubTableUser")
    BaseResponse<String> testInsertSubTableUser(@RequestBody UserInfoDto userReqDto);

    /**
     * 测试根据用户userId更新分表用户数据
     *
     * @param userReqDto
     * @return
     */
    @PutMapping("testUpdateSubTableUser")
    BaseResponse<String> testUpdateSubTableUser(@RequestBody UserInfoDto userReqDto);
}

2.5. 实现类

package com.mayikt.api.impl.member;

import com.mayikt.api.base.BaseApiService;
import com.mayikt.api.base.BaseResponse;
import com.mayikt.api.impl.entity.UserInfoDo;
import com.mayikt.api.impl.mapper.UserInfoMapper;
import com.mayikt.api.member.UserInfoService;
import com.mayikt.api.member.dto.resp.UserInfoDto;
import com.mayikt.api.utils.DesensitizationUtil;
import com.mayikt.api.utils.TokenUtils;
import org.apache.commons.lang3.StringUtils;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class UserInfoServiceImpl extends BaseApiService implements UserInfoService {
    
    
    @Autowired
    private UserInfoMapper userInfoMapper;
    @Autowired
    private TokenUtils tokenUtils;

    @Override
    public BaseResponse<UserInfoDto> getUserInfo(String token) {
    
    
        if (StringUtils.isEmpty(token)) {
    
    
            return setResultError("token 不能为空!");
        }
        // 2.根据token查询 Redis 获取用户的userid
        String tokenValue = tokenUtils.getTokenValue(token);
        if (StringUtils.isEmpty(tokenValue)) {
    
    
            return setResultError("token 可能失效!");
        }
        Long userId = Long.parseLong(tokenValue);
        // 3.根据用户的userid 查询用户信息
        UserInfoDo userInfoDo = userInfoMapper.selectById(userId);
        if (userInfoDo == null) {
    
    
            return setResultError("token错误！");
        }
        UserInfoDto userInfoDto = doToDto(userInfoDo, UserInfoDto.class);
        userInfoDto.setMobile(DesensitizationUtil.mobileEncrypt(userInfoDto.getMobile()));
        return setResultSuccess(userInfoDto);
    }

    /**
     * 测试根据用户userId查询分表用户数据
     *
     * @param userId
     * @return
     */
    @Override
    public BaseResponse<UserInfoDto> testGetSubTableUser(Long userId) {
    
    
        UserInfoDo userInfoDo = userInfoMapper.selectById(userId);
        UserInfoDto userInfoDto = doToDto(userInfoDo, UserInfoDto.class);
        return setResultSuccess(userInfoDto);
    }

    /**
     * 测试根据用户userId删除分表用户数据
     *
     * @param userId
     * @return
     */
    @Override
    public BaseResponse<String> testDelSubTableUser(Long userId) {
    
    
        int result = userInfoMapper.deleteById(userId);
        if (result <= 0) {
    
    
            return setResultError("删除userId->" + userId + "失败");
        }

        return setResultSuccess("删除userId->" + userId + "成功");
    }

    /**
     * 测试增加用户数据到分表中
     *
     * @param userInfoDto
     * @return
     */
    @Override
    public BaseResponse<String> testInsertSubTableUser(UserInfoDto userInfoDto) {
    
    
        UserInfoDo userInfoDo = new UserInfoDo();
        BeanUtils.copyProperties(userInfoDto, userInfoDo);
        int result = userInfoMapper.insert(userInfoDo);
        if (result <= 0) {
    
    
            return setResultError("新增数据失败");
        }

        return setResultSuccess("新增数据成功");
    }

    /**
     * 测试根据用户userId更新分表用户数据
     *
     * @param userInfoDto
     * @return
     */
    @Override
    public BaseResponse<String> testUpdateSubTableUser(UserInfoDto userInfoDto) {
    
    
        UserInfoDo userInfoDo = new UserInfoDo();
        BeanUtils.copyProperties(userInfoDto, userInfoDo);
        int result = userInfoMapper.updateById(userInfoDo);
        if (result <= 0) {
    
    
            return setResultError("更新数据失败");
        }

        return setResultSuccess("更新数据成功");
    }

}

四、测试验证

4.1. 测试增加用户数据到分表中

http://localhost:7000/testInsertSubTableUser

{
    
    
  "userId": 6,
  "mobile": "17610135255",
  "userName": "90架构师",
  "sex": "0",
  "age": 5,
  "createTime": "2014-09-05 18:54:16",
  "isAvalible": "1",
  "picImg": "test_45904720d2ea"
}

4.2. 测试根据用户userId查询分表用户数据

http://localhost:7000/testGetSubTableUser?userId=6

4.3. 测试根据用户userId更新分表用户数据

http://localhost:7000/testUpdateSubTableUser

{
    
    
  "userId": 6,
  "mobile": "17610135255",
  "userName": "90架构师update",
  "sex": "1",
  "age": 2,
  "createTime": "2014-09-05 18:54:16",
  "isAvalible": "1",
  "picImg": "test_45904720d2ea"
}

4.4. 测试根据用户userId删除分表用户数据

http://localhost:7000/testDelSubTableUser?userId=6

4.5. 总结归纳

shadingjdbc 原理：通过增删改查sql进行aop拦截，将表名根据算法策略进行替换。