天机学堂-排行榜功能-day08(六)

接口

一 实时排行榜

1.查询赛季列表功能

PointsBoardSeasonController.java

/** * 查询赛季列表 * @return */@ApiOperation("查询赛季列表")@GetMapping("/list")publicList<PointsBoardSeason>list(){returnpointsBoardSeasonService.list();}

2.实时排行榜功能（基于Zset改造之前的代码）

RedisConstants.java

/** * 积分排行榜的前缀 boards:202501 */StringPOINTS_BOARDS_KEY_PREFIX="boards:";

PointsRecordServiceImpl.java

@OverridepublicvoidaddPointsRecord(LonguserId,intpoint,PointsRecordTypetype){//判断该积分类型是否有上限 type.maxPoints是否大于0if(point<=0){return;}intmaxPoints=type.getMaxPoints();LocalDateTimenow=LocalDateTime.now();if(maxPoints>0){LocalDateTimedayStartTime=DateUtils.getDayStartTime(now);LocalDateTimedayEndTime=DateUtils.getDayEndTime(now);//如果有上限 查询该用户 该积分类型 今日已得积分 points_record 条件userId typeQueryWrapper<PointsRecord>wrapper=newQueryWrapper<>();wrapper.select("sum(points) as totalPoints");wrapper.eq("user_id",userId);wrapper.eq("type",type);wrapper.between("create_time",dayStartTime,dayEndTime);Map<String,Object>map=this.getMap(wrapper);//当前用户该积分类型 已得积分intcurrentPoints=0;if(map!=null&&map.containsKey("totalPoints")){BigDecimaltotalPoints=(BigDecimal)map.get("totalPoints");currentPoints=totalPoints.intValue();}//判断已得积分是否超过上限if(currentPoints>=maxPoints){//说明已得积分 达到上限return;}// 此时的point标识能得得积分if(currentPoints+point>maxPoints){point=maxPoints-currentPoints;}}//保存积分PointsRecordrecord=newPointsRecord();record.setUserId(userId);record.setType(type);record.setPoints(point);this.save(record);// 累计积分添加到Redis当中）（改造部分）Stringkey=RedisConstants.POINTS_BOARDS_KEY_PREFIX+now.format(DateUtils.POINTS_BOARD_SUFFIX_FORMATTER);stringRedisTemplate.opsForZSet().incrementScore(key,userId.toString(),point);}

3.查询学霸积分排行榜

PointsBoardController.java

@ApiOperation("查询学霸积分榜-当前赛季和历史赛季都可用")@GetMappingpublicPointsBoardVOqueryPointsBoardList(PointsBoardQueryquery){returnpointsBoardService.queryPointsBoardList(query);}

IPointsBoardService.java

PointsBoardVOqueryPointsBoardList(PointsBoardQueryquery);

PointsBoardServiceImpl.java

@OverridepublicPointsBoardVOqueryPointsBoardList(PointsBoardQueryquery){// 获取当前登录用户idLonguserId=UserContext.getUser();// 判断是查当前赛季还是历史赛季 query.seasonbooleanisCurrent=query.getSeason()==null||query.getSeason()==0;LocalDatenow=LocalDate.now();Stringformat=now.format(DateTimeFormatter.ofPattern("yyyyMM"));Stringkey=RedisConstants.POINTS_BOARD_KEY_PREFIX+format;Longseason=query.getSeason();// 查询我的排名和积分PointsBoardboard=isCurrent?queryMyCurrentBoard(key):queryMyHistoryBoard(season);// 分页查询赛季列表List<PointsBoard>list=isCurrent?queryCurrentBoard(key,query.getPageNo(),query.getPageSize()):queryHistoryBoard(query);// 封装vo返回PointsBoardVOvo=newPointsBoardVO();vo.setRank(board.getRank());//我的排名vo.setPoints(board.getPoints());//我的积分//封装用户id集合 调用用户服务 获取用户信息 转mapSet<Long>uids=list.stream().map(PointsBoard::getUserId).collect(Collectors.toSet());List<UserDTO>userDTOS=userClient.queryUserByIds(uids);if(userDTOS.isEmpty()){thrownewBizIllegalException("用户不存在");}//转map key:用户id value 用户名称Map<Long,String>userDtoMap=userDTOS.stream().collect(Collectors.toMap(UserDTO::getId,c->c.getName()));List<PointsBoardItemVO>voList=newArrayList<>();for(PointsBoardpointsBoard:list){PointsBoardItemVOitemVO=newPointsBoardItemVO();itemVO.setName(userDtoMap.get(pointsBoard.getUserId()));itemVO.setPoints(pointsBoard.getPoints());itemVO.setRank(pointsBoard.getRank());voList.add(itemVO);}vo.setBoardList(voList);returnvo;}/** * 查询历史赛季排行榜列表 * * @param query * @return */privateList<PointsBoard>queryHistoryBoard(PointsBoardQueryquery){if(query.getPageNo()<=0||query.getPageSize()<=0){thrownewBadRequestException("非法参数");}intoffset=query.getPageNo()-1;List<PointsBoard>list=this.lambdaQuery().eq(PointsBoard::getSeason,query.getSeason()).orderByAsc(PointsBoard::getPoints).last("LIMIT "+query.getPageSize()+" OFFSET "+offset).list();returnlist;}/** * 查询当前赛季排行榜列表 * * @param key * @param pageNo 页码 * @param pageSize 条数 * @return */privateList<PointsBoard>queryCurrentBoard(Stringkey,IntegerpageNo,IntegerpageSize){// 计算start和stop 下标都是从零开始intstart=(pageNo-1)*pageSize;intend=start+pageSize-1;// 利用zrevrange 按分数倒序 分页查询Set<ZSetOperations.TypedTuple<String>>typedTuples=redisTemplate.opsForZSet().reverseRangeByScoreWithScores(key,start,end);if(CollUtils.isEmpty(typedTuples)){returnCollUtils.emptyList();}intrank=start+1;List<PointsBoard>list=newArrayList<>();//封装结果返回for(ZSetOperations.TypedTuple<String>typedTuple:typedTuples){Stringvalue=typedTuple.getValue();//用户idDoublescore=typedTuple.getScore();//总积分值if(StringUtils.isBlank(value)||score==null){continue;}PointsBoardboard=newPointsBoard();board.setUserId(Long.valueOf(value));board.setPoints(score.intValue());board.setRank(rank++);list.add(board);}returnlist;}/** * 查询历史赛季我的积分和排名 * * @param season * @return */privatePointsBoardqueryMyHistoryBoard(Longseason){LonguserId=UserContext.getUser();if(season==null){thrownewBadRequestException("非法参数");}PointsBoardone=this.lambdaQuery().eq(PointsBoard::getSeason,season).eq(PointsBoard::getUserId,userId).one();returnone;}/** * 查询当前赛季我的积分和排名 * * @param key * @return */privatePointsBoardqueryMyCurrentBoard(Stringkey){// 获取当前登录用户idLonguserId=UserContext.getUser();// 从Redis中获取分值Doublescore=redisTemplate.opsForZSet().score(key,userId.toString());// 获取排名 从0开始 需要加一Longrank=redisTemplate.opsForZSet().reverseRank(key,userId.toString());PointsBoardboard=newPointsBoard();board.setRank(rank==null?0:rank.intValue()+1);board.setPoints(score==null?0:score.intValue());returnboard;}

二 历史排行榜

1.定时任务生成榜单表

PointsBoardPersistentHandler.java

@XxlJob("createTableJob")publicvoidcreatePointBoardTableOfLastSeason(){//1.获取上个月的时间LocalDateTimetime=LocalDateTime.now().minusMonths(1);//2.查询赛季idIntegerseasonId=pointsBoardSeasonService.querySeasonIdByTime(time);//3.创建积分榜单表if(seasonId==null){thrownewBadRequestException("当前赛季不存在");}pointsBoardService.createPointsBoardTable(seasonId);}

IPointsBoardSeasonService.java+IPointsBoardService.java

IntegerquerySeasonIdByTime(LocalDateTimetime);voidcreatePointsBoardTable(IntegerseasonId);

PointsBoardSeasonServiceImpl.java+PointsBoardServiceImpl.java

@OverridepublicIntegerquerySeasonIdByTime(LocalDateTimetime){Optional<PointsBoardSeason>pointsBoardSeason=lambdaQuery().le(PointsBoardSeason::getBeginTime,time).ge(PointsBoardSeason::getEndTime,time).oneOpt();returnpointsBoardSeason.map(PointsBoardSeason::getId).orElse(null);}

@Override public void createPointsBoardTable(Integer seasonId) { String tableName = "points_board_" + seasonId; mapper.createPointsBoardTable(tableName); }

PointsBoardMapper

void createPointsBoardTable(@Param("tableName") String seasonId);

PointsBoardMapper.xml

<insertid="createPointsBoardTable">CREATE TABLE if not exists `${tableName}` ( `id` BIGINT NOT NULL AUTO_INCREMENT COMMENT '榜单id', `user_id` BIGINT NOT NULL COMMENT '学生id', `points` INT NOT NULL COMMENT '积分值', PRIMARY KEY (`id`) USING BTREE, INDEX `idx_user_id` (`user_id`) USING BTREE ) COMMENT ='学霸天梯榜' COLLATE = 'utf8mb4_0900_ai_ci' ENGINE = InnoDB ROW_FORMAT = DYNAMIC</insert>

2.定时任务榜单持久化

TableInfoContext

创建一个ThreadLocal工具类在工作线程当中去存储表名

package com.tianji.learning.utils; /** * 获取当前线程的TableInfo对象 * * @author ax */ public class TableInfoContext { private static final ThreadLocal<String> TABLE_INFO = new ThreadLocal<>(); public static void setTableInfo(String tableInfo) { TABLE_INFO.set(tableInfo); } public static String getTableInfo() { return TABLE_INFO.get(); } public static void remove() { TABLE_INFO.remove(); } }

MybatisConfig.java

声明对应的配置类去实现对表名的修改

通过拦截器机制和线程上下文传递，优雅地实现了逻辑表名到物理表名的动态映射。

MybatisConfig搭建了处理流水线，MybatisConfiguration为特定表配置了换名规则，而具体的表名信息则由业务代码通过TableInfoContext在关键时刻传递。整个过程对业务代码入侵极小，是分库分表场景下的经典解决方案。

MybatisConfiguration.java

package com.tianji.learning.config; import com.baomidou.mybatisplus.extension.plugins.handler.TableNameHandler; import com.baomidou.mybatisplus.extension.plugins.inner.DynamicTableNameInnerInterceptor; import com.tianji.learning.utils.TableInfoContext; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import java.util.HashMap; import java.util.Map; /** * mybatis配置类 * * @author ax */ @Configuration public class MybatisConfiguration { @Bean public DynamicTableNameInnerInterceptor dynamicTableNameInnerInterceptor() { Map<String, TableNameHandler> map = new HashMap<>(1); map.put("points_board", (sql, tableName) -> TableInfoContext.getTableInfo()); return new DynamicTableNameInnerInterceptor(map); } }

Mybatis-plus的配置类

packagecom.tianji.common.autoconfigure.mybatis;importcom.baomidou.mybatisplus.annotation.DbType;importcom.baomidou.mybatisplus.core.mapper.BaseMapper;importcom.baomidou.mybatisplus.extension.plugins.MybatisPlusInterceptor;importcom.baomidou.mybatisplus.extension.plugins.inner.DynamicTableNameInnerInterceptor;importcom.baomidou.mybatisplus.extension.plugins.inner.PaginationInnerInterceptor;importorg.springframework.beans.factory.annotation.Autowired;importorg.springframework.boot.autoconfigure.condition.ConditionalOnClass;importorg.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;importorg.springframework.context.annotation.Bean;importorg.springframework.context.annotation.Configuration;@Configuration@ConditionalOnClass({MybatisPlusInterceptor.class,BaseMapper.class})publicclassMybatisConfig{/** * @see MyBatisAutoFillInterceptor 通过自定义拦截器来实现自动注入creater和updater * @deprecated 存在任务更新数据导致updater写入0或null的问题，暂时废弃 */// @Bean// @ConditionalOnMissingBeanpublicBaseMetaObjectHandlerbaseMetaObjectHandler(){returnnewBaseMetaObjectHandler();}@Bean@ConditionalOnMissingBeanpublicMybatisPlusInterceptormybatisPlusInterceptor(@Autowired(required=false)DynamicTableNameInnerInterceptordynamicTableNameInnerInterceptor){MybatisPlusInterceptorinterceptor=newMybatisPlusInterceptor();PaginationInnerInterceptorpaginationInnerInterceptor=newPaginationInnerInterceptor(DbType.MYSQL);paginationInnerInterceptor.setMaxLimit(200L);interceptor.addInnerInterceptor(paginationInnerInterceptor);interceptor.addInnerInterceptor(newMyBatisAutoFillInterceptor());if(dynamicTableNameInnerInterceptor!=null){interceptor.addInnerInterceptor(dynamicTableNameInnerInterceptor);}returninterceptor;}}

PointsBoardPersistentHandler.java

这里还借助了xxljob的分片广播，主要应用于多实例部署时，可以实现多实例分片，类似于取模运算的思路，每个实例负责不同的部分。

@XxlJob("savePointsBoard2DB")publicvoidsavePointsBoard2DB(){//1.获取上个月的时间LocalDateTimetime=LocalDateTime.now().minusMonths(1);//2.查询赛季id// 2.1拼接Redis当中的keyStringkey=RedisConstants.POINTS_BOARDS_KEY_PREFIX+time.format(DateUtils.POINTS_BOARD_SUFFIX_FORMATTER);// 2.2查询数据PointsBoardQuerypointsBoardQuery=newPointsBoardQuery();intindex=XxlJobHelper.getShardIndex();inttotal=XxlJobHelper.getShardTotal();pointsBoardQuery.setPageNo(index+1);pointsBoardQuery.setPageSize(100);// 2.3计算动态表名，存入ThreadLocal中IntegerseasonId=pointsBoardSeasonService.querySeasonIdByTime(time);TableInfoContext.setTableInfo("points_board_"+seasonId);while(true){List<PointsBoard>pointsBoards=pointsBoardService.queryCurrentBoardList(key,pointsBoardQuery);if(CollUtils.isEmpty(pointsBoards)){break;}// 持久化到数据库mapper.saveDb(pointsBoards,TableInfoContext.getTableInfo());//翻页pointsBoardQuery.setPageNo(pointsBoardQuery.getPageNo()+total);}TableInfoContext.remove();}

queryCurrentBoardList方法

@Override public List<PointsBoard> queryCurrentBoardList(String key, PointsBoardQuery query) { Integer pageNo = query.getPageNo(); Integer pageSize = query.getPageSize(); int from = (pageNo - 1) * pageSize; Set<ZSetOperations.TypedTuple<String>> typedTuples = redisTemplate.opsForZSet().reverseRangeWithScores(key, from, from + pageSize - 1); int rank = from + 1; if (CollUtils.isEmpty(typedTuples)) { return CollUtils.emptyList(); } List<PointsBoard> list = new ArrayList<>(typedTuples.size()); for (ZSetOperations.TypedTuple<String> tuple : typedTuples) { String value = tuple.getValue(); Double score = tuple.getScore(); if (score == null || value == null) { continue; } PointsBoard board = new PointsBoard(); board.setUserId(Long.valueOf(value)); board.setPoints(score.intValue()); board.setRank(rank++); list.add(board); } return list; }

PointsBoardMapper.java

void saveDb(@Param("list") List<PointsBoard> pointsBoards, @Param("tableName") String tableName);

PointsBoardMapper.xml

这里是将五个字段修改为三个字段的映射，rank排名映射为id，user_id与points则是普通的映射。

<insert id="saveDb"> insert into ${tableName} (id, user_id, points) values <foreach collection="list" item="item" separator=","> (#{item.rank}, #{item.userId}, #{item.points}) </foreach> </insert>

Redis中del和unlink区别

在Redis中，DEL和UNLINK命令都用于删除键，但它们在实现机制和对系统性能的影响上有显著区别：

1.同步 vs 异步

• DEL命令：同步删除。直接删除键及其关联的数据，操作会立即释放内存。如果删除的键对应大型数据结构（如包含数百万元素的哈希或列表），DEL可能会阻塞主线程，导致其他请求延迟。
• UNLINK命令：异步删除。首先将键从键空间（keyspace）中移除（逻辑删除），后续的内存回收由后台线程处理。命令立即返回，不会阻塞主线程，适合删除大对象。

2.性能影响

• DEL：删除大键时可能引发明显延迟，影响Redis的响应时间。
• UNLINK：几乎无阻塞，适合高吞吐场景，尤其适用于需要频繁删除大键的情况。

3.使用场景

• DEL：适合删除小键或对内存释放时效性要求高的场景（如避免内存不足）。
• UNLINK：推荐在大多数情况下使用，尤其是删除大键或需要低延迟的场景。

4.返回值

• 两者均返回被删除键的数量，但UNLINK返回时数据可能尚未完全释放。

5.版本要求

• UNLINK自Redis 4.0引入，需确保版本支持；DEL在所有版本中可用。

示例对比

# 同步删除，可能阻塞主线程DEL large_key# 异步删除，立即返回，后台清理UNLINK large_key

总结

建议：优先