一、达人探店
1.1 发布探店笔记
需求:

1.1.1 修改图片保存位置






1.1.2 上传探店笔记




1.1.3 查看探店笔记



@GetMapping("/hot")
public Result queryHotBlog(@RequestParam(value = "current", defaultValue = "1") Integer current) {
return blogService.queryHotBlog(current);
}
@GetMapping("/{id}")
public Result queryBlogById(@PathVariable("id") Long id) {
return blogService.queryBlogById(id);
}

public interface IBlogService extends IService<Blog> {
Result queryBlogById(Long id);
Result queryHotBlog(Integer current);
}

package com.hmdp.service.impl;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.hmdp.dto.Result;
import com.hmdp.entity.Blog;
import com.hmdp.entity.User;
import com.hmdp.mapper.BlogMapper;
import com.hmdp.service.IBlogService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.service.IUserService;
import com.hmdp.utils.SystemConstants;
import org.springframework.stereotype.Service;
import javax.annotation.Resource;
import java.util.List;
/**
* <p>
* 服务实现类
* </p>
*
* @author 虎哥
* @since 2021-12-22
*/
@Service
public class BlogServiceImpl extends ServiceImpl<BlogMapper, Blog> implements IBlogService {
@Resource
private IUserService userService;
@Override
public Result queryBlogById(Long id) {
// 1.查询blog
Blog blog = getById(id);
if (blog == null) {
return Result.fail("笔记不存在!");
}
// 2.查询blog有关的用户
queryBlogUser(blog);
return Result.ok(blog);
}
private void queryBlogUser(Blog blog) {
Long userId = blog.getUserId();
User user = userService.getById(userId);
blog.setName(user.getNickName());
blog.setIcon(user.getIcon());
}
@Override
public Result queryHotBlog(Integer current) {
// 根据用户查询
Page<Blog> page = query()
.orderByDesc("liked")
.page(new Page<>(current, SystemConstants.MAX_PAGE_SIZE));
// 获取当前页数据
List<Blog> records = page.getRecords();
// 查询用户
records.forEach(this::queryBlogUser);
return Result.ok(records);
}
}
测试验证:


1.2 点赞




1.2.1 返回给前端判断用户是否点赞

说明:
@TableField(exist = false)说明该字段不在表中。

@PutMapping("/like/{id}")
public Result likeBlog(@PathVariable("id") Long id) {
// 修改点赞数量
return blogService.likeBlog(id);
}



package com.hmdp.service.impl;
import cn.hutool.core.util.BooleanUtil;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.hmdp.dto.Result;
import com.hmdp.entity.Blog;
import com.hmdp.entity.User;
import com.hmdp.mapper.BlogMapper;
import com.hmdp.service.IBlogService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.service.IUserService;
import com.hmdp.utils.SystemConstants;
import com.hmdp.utils.UserHolder;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Service;
import javax.annotation.Resource;
import java.util.List;
/**
* <p>
* 服务实现类
* </p>
*
* @author 虎哥
* @since 2021-12-22
*/
@Service
public class BlogServiceImpl extends ServiceImpl<BlogMapper, Blog> implements IBlogService {
@Resource
private IUserService userService;
@Override
public Result queryBlogById(Long id) {
// 1.查询blog
Blog blog = getById(id);
if (blog == null) {
return Result.fail("笔记不存在!");
}
// 2.查询blog有关的用户
queryBlogUser(blog);
//3.查询blog是否被点赞
isBlogLiked(blog);
return Result.ok(blog);
}
private void queryBlogUser(Blog blog) {
Long userId = blog.getUserId();
User user = userService.getById(userId);
blog.setName(user.getNickName());
blog.setIcon(user.getIcon());
}
@Override
public Result queryHotBlog(Integer current) {
// 根据用户查询
Page<Blog> page = query()
.orderByDesc("liked")
.page(new Page<>(current, SystemConstants.MAX_PAGE_SIZE));
// 获取当前页数据
List<Blog> records = page.getRecords();
// 查询用户
records.forEach(blog ->{
this.queryBlogUser(blog);
this.isBlogLiked(blog);
});
return Result.ok(records);
}
@Resource
private StringRedisTemplate stringRedisTemplate;
@Override
public Result likeBlog(Long id) {
//1.获取登录用户
Long userId = UserHolder.getUser().getId();
String key= "blog:like:"+id;
//2.判断当前登录用户是否已经点赞
Boolean isMember = stringRedisTemplate.opsForSet().isMember(key,userId.toString());
if(BooleanUtil.isFalse(isMember)){
//3.如果未点赞,可以点赞
//3.1 数据库点赞数+1
boolean isSuccess=update().setSql("liked = liked+1").eq("id",id).update();
//3.2 保存用户到Redis的set集合
if(isSuccess){
stringRedisTemplate.opsForSet().add(key,userId.toString());
}
}else{
//4.如果已点赞,取消点赞
//4.1 数据库点赞数-1
boolean isSuccess=update().setSql("liked = liked-1").eq("id",id).update();
//4.2把用户从redis的set集合中移除
if(isSuccess){
stringRedisTemplate.opsForSet().remove(key,userId.toString());
}
}
return Result.ok();
}
private void isBlogLiked(Blog blog) {
//1.获取登录用户
Long userId = UserHolder.getUser().getId();
String key= "blog:like:"+blog.getId();
//2.判断当前登录用户是否已经点赞
Boolean isMember = stringRedisTemplate.opsForSet().isMember(key,userId.toString());
blog.setIsLike(BooleanUtil.isTrue(isMember));
}
}
启动服务验证:



1.3 点赞排行榜(展示前5个点赞用户)


思路:改用SortedSet实现保存笔记的所有点赞用户,既可以实现排序,又可以根据元素查找(List虽有序但是只能按索引查找)。
注意:sortedset没有sismember命令,可以用zscore命令代替,zscore命令返回分数则元素存在,返回nil则不存在;使用zrange命令查询前5名。


@GetMapping("/likes/{id}")
public Result queryBlogLikes(@PathVariable("id") Long id) {
return blogService.queryBloglikes(id);
}

package com.hmdp.service.impl;
import cn.hutool.core.bean.BeanUtil;
import cn.hutool.core.util.BooleanUtil;
import cn.hutool.core.util.StrUtil;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.hmdp.dto.Result;
import com.hmdp.dto.UserDTO;
import com.hmdp.entity.Blog;
import com.hmdp.entity.User;
import com.hmdp.mapper.BlogMapper;
import com.hmdp.service.IBlogService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.service.IUserService;
import com.hmdp.utils.SystemConstants;
import com.hmdp.utils.UserHolder;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Service;
import javax.annotation.Resource;
import java.util.Collections;
import java.util.List;
import java.util.Set;
import java.util.stream.Collectors;
import static com.hmdp.utils.RedisConstants.BLOG_LIKED_KEY;
/**
* <p>
* 服务实现类
* </p>
*
* @author 虎哥
* @since 2021-12-22
*/
@Service
public class BlogServiceImpl extends ServiceImpl<BlogMapper, Blog> implements IBlogService {
@Resource
private IUserService userService;
@Override
public Result queryBlogById(Long id) {
// 1.查询blog
Blog blog = getById(id);
if (blog == null) {
return Result.fail("笔记不存在!");
}
// 2.查询blog有关的用户
queryBlogUser(blog);
//3.查询blog是否被点赞
isBlogLiked(blog);
return Result.ok(blog);
}
private void queryBlogUser(Blog blog) {
Long userId = blog.getUserId();
User user = userService.getById(userId);
blog.setName(user.getNickName());
blog.setIcon(user.getIcon());
}
@Override
public Result queryHotBlog(Integer current) {
// 根据用户查询
Page<Blog> page = query()
.orderByDesc("liked")
.page(new Page<>(current, SystemConstants.MAX_PAGE_SIZE));
// 获取当前页数据
List<Blog> records = page.getRecords();
// 查询用户
records.forEach(blog ->{
this.queryBlogUser(blog);
this.isBlogLiked(blog);
});
return Result.ok(records);
}
@Resource
private StringRedisTemplate stringRedisTemplate;
@Override
public Result likeBlog(Long id) {
//1.获取登录用户
Long userId = UserHolder.getUser().getId();
String key= BLOG_LIKED_KEY+id;
//2.判断当前登录用户是否已经点赞
Double score = stringRedisTemplate.opsForZSet().score(key,userId.toString());
if(score==null){
//3.如果未点赞,可以点赞
//3.1 数据库点赞数+1
boolean isSuccess=update().setSql("liked = liked+1").eq("id",id).update();
//3.2 保存用户到Redis的set集合
if(isSuccess){
stringRedisTemplate.opsForZSet().add(key,userId.toString(),System.currentTimeMillis());
}
}else{
//4.如果已点赞,取消点赞
//4.1 数据库点赞数-1
boolean isSuccess=update().setSql("liked = liked-1").eq("id",id).update();
//4.2把用户从redis的set集合中移除
if(isSuccess){
stringRedisTemplate.opsForZSet().remove(key,userId.toString());
}
}
return Result.ok();
}
@Override
public Result queryBloglikes(Long id) {
String key = BLOG_LIKED_KEY + id;
// 1.查询top5的点赞用户 zrange key 0 4
Set<String> top5 = stringRedisTemplate.opsForZSet().range(key, 0, 4);
if (top5 == null || top5.isEmpty()) {
return Result.ok(Collections.emptyList());
}
// 2.解析出其中的用户id
List<Long> ids = top5.stream().map(Long::valueOf).collect(Collectors.toList());
String idStr = StrUtil.join(",", ids);
// 3.根据用户id查询用户 WHERE id IN ( 5 , 1 ) ORDER BY FIELD(id, 5, 1)
List<UserDTO> userDTOS = userService.query()
.in("id", ids).last("ORDER BY FIELD(id," + idStr + ")").list()
.stream()
.map(user -> BeanUtil.copyProperties(user, UserDTO.class))
.collect(Collectors.toList());
// 4.返回
return Result.ok(userDTOS);
}
private void isBlogLiked(Blog blog) {
//1.获取登录用户
UserDTO user = UserHolder.getUser();
if(user==null){
//用户未登录,无需查询是否先赞
return;
}
Long userId= user.getId();
String key= BLOG_LIKED_KEY+blog.getId();
//2.判断当前登录用户是否已经点赞
Double score = stringRedisTemplate.opsForZSet().score(key,userId.toString());
blog.setIsLike(score!=null);
}
}

二、好友关注
2.1 关注和取关



@RestController
@RequestMapping("/follow")
public class FollowController {
@Resource
private IFollowService followService;
@PutMapping("/{id}/{isFollow}")
public Result follow(@PathVariable("id") Long followUserId, @PathVariable("isFollow") Boolean isFollow) {
return followService.follow(followUserId, isFollow);
}
@GetMapping("/or/not/{id}")
public Result isFollow(@PathVariable("id") Long followUserId) {
return followService.isFollow(followUserId);
}
}

public interface IFollowService extends IService<Follow> {
Result follow(Long followUserId, Boolean isFollow);
Result isFollow(Long followUserId);
}

@Service
public class FollowServiceImpl extends ServiceImpl<FollowMapper, Follow> implements IFollowService {
@Resource
private StringRedisTemplate stringRedisTemplate;
@Resource
private IUserService userService;
@Override
public Result follow(Long followUserId, Boolean isFollow) {
// 1.获取登录用户
Long userId = UserHolder.getUser().getId();
String key = "follows:" + userId;
// 1.判断到底是关注还是取关
if (isFollow) {
// 2.关注,新增数据
Follow follow = new Follow();
follow.setUserId(userId);
follow.setFollowUserId(followUserId);
boolean isSuccess = save(follow);
if (isSuccess) {
// 把关注用户的id(方便后面获取共同关注),放入redis的set集合 sadd userId followerUserId
stringRedisTemplate.opsForSet().add(key, followUserId.toString());
}
} else {
// 3.取关,删除 delete from tb_follow where user_id = ? and follow_user_id = ?
boolean isSuccess = remove(new QueryWrapper<Follow>()
.eq("user_id", userId).eq("follow_user_id", followUserId));
if (isSuccess) {
// 把关注用户的id从Redis集合中移除
stringRedisTemplate.opsForSet().remove(key, followUserId.toString());
}
}
return Result.ok();
}
@Override
public Result isFollow(Long followUserId) {
// 1.获取登录用户
Long userId = UserHolder.getUser().getId();
// 2.查询是否关注 select count(*) from tb_follow where user_id = ? and follow_user_id = ?
Integer count = query().eq("user_id", userId).eq("follow_user_id", followUserId).count();
// 3.判断
return Result.ok(count > 0);
}
}
测试验证:

2.2 共同关注


@GetMapping("/{id}")
public Result queryUserById(@PathVariable("id") Long userId){
// 查询详情
User user = userService.getById(userId);
if (user == null) {
return Result.ok();
}
UserDTO userDTO = BeanUtil.copyProperties(user, UserDTO.class);
// 返回
return Result.ok(userDTO);
}

@GetMapping("/of/user")
public Result queryBlogByUserId(
@RequestParam(value = "current", defaultValue = "1") Integer current,
@RequestParam("id") Long id) {
// 根据用户查询
Page<Blog> page = blogService.query()
.eq("user_id", id).page(new Page<>(current, SystemConstants.MAX_PAGE_SIZE));
// 获取当前页数据
List<Blog> records = page.getRecords();
return Result.ok(records);
}
验证:




@GetMapping("/common/{id}")
public Result followCommons(@PathVariable("id") Long id){
return followService.followCommons(id);
}


@Override
public Result followCommons(Long id) {
// 1.获取当前用户
Long userId = UserHolder.getUser().getId();
String key = "follows:" + userId;
// 2.求交集
String key2 = "follows:" + id;
Set<String> intersect = stringRedisTemplate.opsForSet().intersect(key, key2);
if (intersect == null || intersect.isEmpty()) {
// 无交集
return Result.ok(Collections.emptyList());
}
// 3.解析id集合
List<Long> ids = intersect.stream().map(Long::valueOf).collect(Collectors.toList());
// 4.查询用户
List<UserDTO> users = userService.listByIds(ids)
.stream()
.map(user -> BeanUtil.copyProperties(user, UserDTO.class))
.collect(Collectors.toList());
return Result.ok(users);
}
测试验证:


2.3 关注推送(推送好友笔记)
推送:用户发布笔记时推送给所有的关注的人。



使用Timeline模式实现关注的所有用户的笔记浏览功能:


选用sortedset数据类型。
2.3.1 发布笔记并推送


@Resource
private IFollowService followService;
@Override
public Result saveBlog(Blog blog) {
// 1.获取登录用户
UserDTO user = UserHolder.getUser();
blog.setUserId(user.getId());
// 2.保存探店笔记
boolean isSuccess = save(blog);
if(!isSuccess){
return Result.fail("新增笔记失败!");
}
// 3.查询笔记作者的所有粉丝 select * from tb_follow where follow_user_id = ?
List<Follow> follows = followService.query().eq("follow_user_id", user.getId()).list();
// 4.推送笔记id给所有粉丝
for (Follow follow : follows) {
// 4.1.获取粉丝id
Long userId = follow.getUserId();
// 4.2.推送
String key = FEED_KEY + userId;
stringRedisTemplate.opsForZSet().add(key, blog.getId().toString(), System.currentTimeMillis());
}
// 5.返回id
return Result.ok(blog.getId());
}
2.3.2 查看关注用户的笔记(滚动分页查询)
补充:sortedset的zrange指令是按顺序排列,zrevrange是按倒序排列。
例如:

滚动查询,记录上一页查询的最后一个元素,下一次查询从该元素往后,避免按照下标查询在查询过程中新增元素导致重复查询。
redis命令实现如下:

实现:


@Data
public class ScrollResult {
private List<?> list;
private Long minTime;
private Integer offset;
}

@GetMapping("/of/follow")
public Result queryBlogOfFollow(
@RequestParam("lastId") Long max, @RequestParam(value = "offset", defaultValue = "0") Integer offset){
return blogService.queryBlogOfFollow(max, offset);
}


@Override
public Result queryBlogOfFollow(Long max, Integer offset) {
// 1.获取当前用户
Long userId = UserHolder.getUser().getId();
// 2.查询收件箱 ZREVRANGEBYSCORE key Max Min LIMIT offset count
String key = FEED_KEY + userId;
Set<ZSetOperations.TypedTuple<String>> typedTuples = stringRedisTemplate.opsForZSet()
.reverseRangeByScoreWithScores(key, 0, max, offset, 2);
// 3.非空判断
if (typedTuples == null || typedTuples.isEmpty()) {
return Result.ok();
}
// 4.解析数据:blogId、minTime(时间戳)、offset
List<Long> ids = new ArrayList<>(typedTuples.size());
long minTime = 0; // 2
int os = 1; // 2
for (ZSetOperations.TypedTuple<String> tuple : typedTuples) { // 5 4 4 2 2
// 4.1.获取id
ids.add(Long.valueOf(tuple.getValue()));
// 4.2.获取分数(时间戳)
long time = tuple.getScore().longValue();
if(time == minTime){
os++;
}else{
minTime = time;
os = 1;
}
}
// 5.根据id查询blog
String idStr = StrUtil.join(",", ids);
List<Blog> blogs = query().in("id", ids).last("ORDER BY FIELD(id," + idStr + ")").list();
for (Blog blog : blogs) {
// 5.1.查询blog有关的用户
queryBlogUser(blog);
// 5.2.查询blog是否被点赞
isBlogLiked(blog);
}
// 6.封装并返回
ScrollResult r = new ScrollResult();
r.setList(blogs);
r.setOffset(os);
r.setMinTime(minTime);
return Result.ok(r);
}
测试验证:





三、附近商铺
3.1 GEO数据结构

例如:

添加元素:

geoadd g1 116.378248 39.865275 bjn 116.42803 39.903938 bj 116.322287 39.893729 bjx



geodist g1 bjn bjx
geodist g1 bjn bjx m
geodist g1 bjn bjx km

geosearch g1 fromlonlat 116.397904 39.909005 byradius 10 km withdist

geopos g1 bj

geohash g1 bj
3.2 将商铺数据存到redis

url中携带的参数说明:

redis数据存储方案:


编写测试代码:

@SpringBootTest
class HmDianPingApplicationTests {
@Resource
private ShopServiceImpl shopService;
@Resource
private StringRedisTemplate stringRedisTemplate;
@Test
void loadShopData() {
// 1.查询店铺信息
List<Shop> list = shopService.list();
// 2.把店铺分组,按照typeId分组,typeId一致的放到一个集合
Map<Long, List<Shop>> map = list.stream().collect(Collectors.groupingBy(Shop::getTypeId));
// 3.分批完成写入Redis
for (Map.Entry<Long, List<Shop>> entry : map.entrySet()) {
// 3.1.获取类型id
Long typeId = entry.getKey();
String key = SHOP_GEO_KEY + typeId;
// 3.2.获取同类型的店铺的集合
List<Shop> value = entry.getValue();
List<RedisGeoCommands.GeoLocation<String>> locations = new ArrayList<>(value.size());
// 3.3.写入redis GEOADD key 经度 纬度 member
for (Shop shop : value) {
// stringRedisTemplate.opsForGeo().add(key, new Point(shop.getX(), shop.getY()), shop.getId().toString());
locations.add(new RedisGeoCommands.GeoLocation<>(
shop.getId().toString(),
new Point(shop.getX(), shop.getY())
));
}
stringRedisTemplate.opsForGeo().add(key, locations);
}
}
}
运行test方法结果如下:

3.3 代码实现
注意:
StringDataRedis的2.3.9版本并不支持Redis6.2提供的GEOSEARCH命令,需要修改版本。

<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-redis</artifactId>
<exclusions>
<exclusion>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-redis</artifactId>
</exclusion>
<exclusion>
<groupId>lettuce-core</groupId>
<artifactId>io.lettuce</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-redis</artifactId>
<version>2.6.2</version>
</dependency>
<dependency>
<groupId>io.lettuce</groupId>
<artifactId>lettuce-core</artifactId>
<version>6.1.6.RELEASE</version>
</dependency>

@GetMapping("/of/type")
public Result queryShopByType(
@RequestParam("typeId") Integer typeId,
@RequestParam(value = "current", defaultValue = "1") Integer current,
@RequestParam(value = "x", required = false) Double x,
@RequestParam(value = "y", required = false) Double y
) {
return shopService.queryShopByType(typeId, current, x, y);
}


@Override
public Result queryShopByType(Integer typeId, Integer current, Double x, Double y) {
// 1.判断是否需要根据坐标查询
if (x == null || y == null) {
// 不需要坐标查询,按数据库查询
Page<Shop> page = query()
.eq("type_id", typeId)
.page(new Page<>(current, SystemConstants.DEFAULT_PAGE_SIZE));
// 返回数据
return Result.ok(page.getRecords());
}
// 2.计算分页参数
int from = (current - 1) * SystemConstants.DEFAULT_PAGE_SIZE;
int end = current * SystemConstants.DEFAULT_PAGE_SIZE;
// 3.查询redis、按照距离排序、分页。结果:shopId、distance
String key = SHOP_GEO_KEY + typeId;
GeoResults<RedisGeoCommands.GeoLocation<String>> results = stringRedisTemplate.opsForGeo() // GEOSEARCH key BYLONLAT x y BYRADIUS 10 WITHDISTANCE
.search(
key,
GeoReference.fromCoordinate(x, y),
new Distance(5000),
RedisGeoCommands.GeoSearchCommandArgs.newGeoSearchArgs().includeDistance().limit(end)
);
// 4.解析出id
if (results == null) {
return Result.ok(Collections.emptyList());
}
List<GeoResult<RedisGeoCommands.GeoLocation<String>>> list = results.getContent();
if (list.size() <= from) {
// 没有下一页了,结束
return Result.ok(Collections.emptyList());
}
// 4.1.截取 from ~ end的部分
List<Long> ids = new ArrayList<>(list.size());
Map<String, Distance> distanceMap = new HashMap<>(list.size());
list.stream().skip(from).forEach(result -> {
// 4.2.获取店铺id
String shopIdStr = result.getContent().getName();
ids.add(Long.valueOf(shopIdStr));
// 4.3.获取距离
Distance distance = result.getDistance();
distanceMap.put(shopIdStr, distance);
});
// 5.根据id查询Shop
String idStr = StrUtil.join(",", ids);
List<Shop> shops = query().in("id", ids).last("ORDER BY FIELD(id," + idStr + ")").list();
for (Shop shop : shops) {
shop.setDistance(distanceMap.get(shop.getId().toString()).getValue());
}
// 6.返回
return Result.ok(shops);
}

四、用户签到
4.1 BitMap用法
例如用户签到的记录,如果使用mysql数据库表存储,每次用户前一次到就生成一条记录,则如果用户量达千万那么一年占用的存储空间非常大。而如果使用redis中的位图,用32bit(4字节)就可以记录一个用户一个月的签到结果。


例如:

setbit bm1 0 1


结果为:11100111
(注意:有些版本的客户端无法查看binary格式的数据)

getbit bm1 1
getbit bm1 3

bitcount bm1

bitfield bm1 get u4 0

bitpos bm1 0 0
注意:bitpos的最后的索引参数单位为字节而不是位。
例如:


4.2 实现签到功能


@PostMapping("/sign")
public Result sign(){
return userService.sign();
}


@Override
public Result sign() {
// 1.获取当前登录用户
Long userId = UserHolder.getUser().getId();
// 2.获取日期
LocalDateTime now = LocalDateTime.now();
// 3.拼接key
String keySuffix = now.format(DateTimeFormatter.ofPattern(":yyyyMM"));
String key = USER_SIGN_KEY + userId + keySuffix;
// 4.获取今天是本月的第几天
int dayOfMonth = now.getDayOfMonth();
// 5.写入Redis SETBIT key offset 1
stringRedisTemplate.opsForValue().setBit(key, dayOfMonth - 1, true);
return Result.ok();
}
4.3 签到统计
统计连续签到天数(今天往前连续的签到天数之和)。

@GetMapping("/sign/count")
public Result signCount(){
return userService.signCount();
}


@Override
public Result signCount() {
// 1.获取当前登录用户
Long userId = UserHolder.getUser().getId();
// 2.获取日期
LocalDateTime now = LocalDateTime.now();
// 3.拼接key
String keySuffix = now.format(DateTimeFormatter.ofPattern(":yyyyMM"));
String key = USER_SIGN_KEY + userId + keySuffix;
// 4.获取今天是本月的第几天
int dayOfMonth = now.getDayOfMonth();
// 5.获取本月截止今天为止的所有的签到记录,返回的是一个十进制的数字 BITFIELD sign:5:202203 GET u14 0
List<Long> result = stringRedisTemplate.opsForValue().bitField(
key,
BitFieldSubCommands.create()
.get(BitFieldSubCommands.BitFieldType.unsigned(dayOfMonth)).valueAt(0)
);
if (result == null || result.isEmpty()) {
// 没有任何签到结果
return Result.ok(0);
}
Long num = result.get(0);
if (num == null || num == 0) {
return Result.ok(0);
}
// 6.循环遍历
int count = 0;
while (true) {
// 6.1.让这个数字与1做与运算,得到数字的最后一个bit位 // 判断这个bit位是否为0
if ((num & 1) == 0) {
// 如果为0,说明未签到,结束
break;
}else {
// 如果不为0,说明已签到,计数器+1
count++;
}
// 把数字右移一位,抛弃最后一个bit位,继续下一个bit位
num >>>= 1;
}
return Result.ok(count);
}
五、UV统计
5.1 HyperLogLog的用法



pfadd hl1 e1 e2 e3 e4 e5
pfcount hl1
pfadd hl1 e3 e5 e6
5.2 测试百万数据统计占用的内存

@Test
void testHyperLogLog() {
String[] values = new String[1000];
int j = 0;
for (int i = 0; i < 1000000; i++) {
j = i % 1000;
values[j] = "user_" + i;
if(j == 999){
// 发送到Redis
stringRedisTemplate.opsForHyperLogLog().add("hl2", values);
}
}
// 统计数量
Long count = stringRedisTemplate.opsForHyperLogLog().size("hl2");
System.out.println("count = " + count);
}



(901696-887312)/1024=14.046875(KB),百万数据只占用了这些大小。
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