12.2_黑马Redis实战篇达人探店好友关注

2023-12-02 17:36

本文主要是介绍12.2_黑马Redis实战篇达人探店好友关注,希望对大家解决编程问题提供一定的参考价值,需要的开发者们随着小编来一起学习吧!

目录

实战篇03

thinking :提取公共部分为一个方法的快捷键?

thinking:redis中的ismember?

thinking:BooleanUtil.isTrue?

实战篇04

thinking:zscore的用法?

thinking:stream().map().collect?

thinking:引用静态方法?JAVA中的双冒号? 

thinking:StringUtils.join的用法?

thinking:StrUtil.join()?

实战篇05

实战篇06

thinking:在redis中求交集?  用inersect。

实战篇07

实战篇08

thinking:System.currentTimeMillis()?

​编辑 thinking:时间戳?​编辑

实战篇09

实战篇10

​编辑 thinking:JAVA中的long和int有什么区别?

thinking:为什么long类型的变量需要加上L?float类型的变量要加上F?


实战篇03

thinking :提取公共部分为一个方法的快捷键?

ctrl + alt + m

thinking:redis中的ismember?

redis五大集合之一(Set集合常用命令)_redis set ismember-CSDN博客

可以简化为:

thinking:BooleanUtil.isTrue?

hutool工具包快速入门_beanutil.fillbeanwithmap-CSDN博客

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 {@Resourceprivate IUserService userService;@Resourceprivate StringRedisTemplate stringRedisTemplate;@Overridepublic 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.isBlockLiked(blog);});return Result.ok(records);}@Overridepublic Result queryBlogById(Long id) {//1. 查询blogBlog 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isBlockLiked(blog);return Result.ok(blog);}private void isBlockLiked(Blog blog) {//1.判断当前登录用户Long userId = UserHolder.getUser().getId();//2.判断当前登录用户是否已经点赞String key ="blog:liked:"+blog.getId();Boolean isMember = stringRedisTemplate.opsForSet().isMember(key, userId.toString());blog.setIsLike(BooleanUtil.isTrue(isMember));}@Overridepublic Result likeBlog(Long id) {//1.判断当前登录用户Long userId = UserHolder.getUser().getId();//2.判断当前登录用户是否已经点赞String key ="blog:liked:"+id;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 +1boolean 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 -1boolean isSuccess = update().setSql("liked = liked + 1").eq("id", id).update();//4.2把用户从Redis的set集合移除if (isSuccess) {stringRedisTemplate.opsForSet().remove(key, userId.toString());}}return Result.ok();}private void queryBlogUser(Blog blog) {Long userId = blog.getUserId();User user = userService.getById(userId);blog.setName(user.getNickName());blog.setIcon(user.getIcon());}
}

实战篇04

thinking:zscore的用法?

Redis zrangebylex的使用 | Redis sorted_set不可不知的秘密_血煞长虹的博客-CSDN博客

thinking:stream().map().collect?

thinking:引用静态方法?JAVA中的双冒号? 

当时看黑马上下部的时候一直没有搞懂的内容之一。现在来恶补一下。

方法引用-02-引用静态方法_哔哩哔哩_bilibili

 

 

 

接着判断它是否符合以下三个要求

接着,我们来看看视频中的例子

Java中Long::valueOf是什么意思_long.valueof-CSDN博客

 有几篇讲JAVA双冒号的文章也挺好的,可以看看。

深入理解Java双冒号(::)运算符的使用(*)_java 双冒号_Firm陈的博客-CSDN博客

Java 中的双冒号“::”_java ::_JFS_Study的博客-CSDN博客  

 发现很多知识点当时很难理解,一段时间之后就突然开窍。

遂决定明年暑假前把JAVA基础篇再二刷一遍。

thinking:StringUtils.join的用法?

StringUtils.join的用法_stringutils.join用法-CSDN博客

thinking:StrUtil.join()?

Hutool Java开发工具包_strutil.join-CSDN博客

 Hutool,轻松玩转字符串操作, 都是案例,值得收藏!_hutool 字符串拼接-CSDN博客

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 {@Resourceprivate IUserService userService;@Resourceprivate StringRedisTemplate stringRedisTemplate;@Overridepublic 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.isBlockLiked(blog);});return Result.ok(records);}@Overridepublic Result queryBlogById(Long id) {//1. 查询blogBlog 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isBlockLiked(blog);return Result.ok(blog);}private void isBlockLiked(Blog blog) {//1.获取登录用户UserDTO user = UserHolder.getUser();if(user == null){//用户未登录,无需查询是否点赞return;}//1.判断当前登录用户Long userId = UserHolder.getUser().getId();//2.判断当前登录用户是否已经点赞String key ="blog:liked:"+blog.getId();Double score = stringRedisTemplate.opsForZSet().score(key, userId.toString());blog.setIsLike(score != null);}@Overridepublic Result likeBlog(Long id) {//1.判断当前登录用户Long userId = UserHolder.getUser().getId();//2.判断当前登录用户是否已经点赞String key =BLOG_LIKED_KEY+id;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 +1boolean 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 -1boolean isSuccess = update().setSql("liked = liked + 1").eq("id", id).update();//4.2把用户从Redis的set集合移除if (isSuccess) {stringRedisTemplate.opsForZSet().remove(key, userId.toString());}}return Result.ok();}@Overridepublic Result queryBlogLikes(Long id) {String key =BLOG_LIKED_KEY + id;//1.查询top5的点赞用户 zrange key 0 4Set<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idList<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 queryBlogUser(Blog blog) {Long userId = blog.getUserId();User user = userService.getById(userId);blog.setName(user.getNickName());blog.setIcon(user.getIcon());}
}

实战篇05

package com.hmdp.service.impl;import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.hmdp.dto.Result;
import com.hmdp.entity.Follow;
import com.hmdp.mapper.FollowMapper;
import com.hmdp.service.IFollowService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.utils.UserHolder;
import org.springframework.stereotype.Service;/*** <p>*  服务实现类* </p>** @author 虎哥* @since 2021-12-22*/
@Service
public class FollowServiceImpl extends ServiceImpl<FollowMapper, Follow> implements IFollowService {@Overridepublic Result follow(Long followUserId, Boolean isFollow) {//1.获取登录用户Long userId = UserHolder.getUser().getId();//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);save(follow);}else{//3.取关,删除remove(new QueryWrapper<Follow>().eq("user_id",userId).eq("follow_user_id",followUserId));}return Result.ok();}@Overridepublic Result isFollow(Long followUserId) {//1.获取登录用户Long userId = UserHolder.getUser().getId();//2.查询是否关注Integer count = query().eq("user_id", userId).eq("follow_user_id", followUserId).count();return Result.ok(count > 0 );}
}

实战篇06

thinking:在redis中求交集?  用inersect。

package com.hmdp.service.impl;import cn.hutool.core.bean.BeanUtil;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.hmdp.dto.Result;
import com.hmdp.dto.UserDTO;
import com.hmdp.entity.Follow;
import com.hmdp.mapper.FollowMapper;
import com.hmdp.service.IFollowService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.service.IUserService;
import com.hmdp.utils.CacheClient;
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;/*** <p>*  服务实现类* </p>** @author 虎哥* @since 2021-12-22*/
@Service
public class FollowServiceImpl extends ServiceImpl<FollowMapper, Follow> implements IFollowService {@Resourceprivate StringRedisTemplate stringRedisTemplate;@Resourceprivate IUserService userService;@Overridepublic 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,放入redis的set集合stringRedisTemplate.opsForSet().add(key,followUserId.toString());}} else{//3.取关,删除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();}@Overridepublic Result isFollow(Long followUserId) {//1.获取登录用户Long userId = UserHolder.getUser().getId();//2.查询是否关注Integer count = query().eq("user_id", userId).eq("follow_user_id", followUserId).count();return Result.ok(count > 0 );}@Overridepublic 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);}
}

实战篇07

实战篇08

对于数据经常发生变化的,用sortset处理分页问题 

thinking:System.currentTimeMillis()?

System.currentTimeMillis()用法及其计算方式与时间的单位转换_Tan.]der的博客-CSDN博客

Java获取当前系统时间-CSDN博客

 thinking:时间戳?

 获取系统时间以及时间戳的理解与使用_系统时间戳-CSDN博客

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.Follow;
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.IFollowService;
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 {@Resourceprivate IUserService userService;@Resourceprivate StringRedisTemplate stringRedisTemplate;@Resourceprivate IFollowService followService;@Overridepublic 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.isBlockLiked(blog);});return Result.ok(records);}@Overridepublic Result queryBlogById(Long id) {//1. 查询blogBlog 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isBlockLiked(blog);return Result.ok(blog);}private void isBlockLiked(Blog blog) {//1.获取登录用户UserDTO user = UserHolder.getUser();if(user == null){//用户未登录,无需查询是否点赞return;}//1.判断当前登录用户Long userId = UserHolder.getUser().getId();//2.判断当前登录用户是否已经点赞String key ="blog:liked:"+blog.getId();Double score = stringRedisTemplate.opsForZSet().score(key, userId.toString());blog.setIsLike(score != null);}@Overridepublic Result likeBlog(Long id) {//1.判断当前登录用户Long userId = UserHolder.getUser().getId();//2.判断当前登录用户是否已经点赞String key =BLOG_LIKED_KEY+id;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 +1boolean 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 -1boolean isSuccess = update().setSql("liked = liked + 1").eq("id", id).update();//4.2把用户从Redis的set集合移除if (isSuccess) {stringRedisTemplate.opsForZSet().remove(key, userId.toString());}}return Result.ok();}@Overridepublic Result queryBlogLikes(Long id) {String key =BLOG_LIKED_KEY + id;//1.查询top5的点赞用户 zrange key 0 4Set<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idList<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);}@Overridepublic 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idLong userId = follow.getUserId();//4.2推送String key = "feed:" + userId;stringRedisTemplate.opsForZSet().add(key,blog.getId().toString(),System.currentTimeMillis());}//5 返回idreturn Result.ok(blog.getId());}private void queryBlogUser(Blog blog) {Long userId = blog.getUserId();User user = userService.getById(userId);blog.setName(user.getNickName());blog.setIcon(user.getIcon());}
}

实战篇09

实战篇10

 thinking:JAVA中的long和int有什么区别?

 java long 区别_java中long和int的区别-CSDN博客

thinking:为什么long类型的变量需要加上L?float类型的变量要加上F?

运算符-04-05-隐式转换和强制转换_哔哩哔哩_bilibili

意思就是说:30本身是int类型,可是你现在想要它变成long类型。

而JAVA中的隐形转化,会自动将int类型转化未long类型。

因此,JAVA把你想做的事情帮你做了。因此,long num1 = 30 才可以成立

而1111111111111111111超过了int的取值范围,就已经出bug了。无法再帮你转long类型了

而double的取值范围最大,就无法自动转化了。得自己手动转化才可以。 

为什么定义long类型跟float类型的变量时要加L和F_java中long类型为什么要加l_Cristo_Li的博客-CSDN博客

【Java】double|float 区别_java float和double-CSDN博客

 

listByIds 无法保证在数据库中按照一定的顺序进行查找,因此要用自定义sql语句才可以完成这个操作。

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.ScrollResult;
import com.hmdp.dto.UserDTO;
import com.hmdp.entity.Blog;
import com.hmdp.entity.Follow;
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.IFollowService;
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.data.redis.core.ZSetOperations;
import org.springframework.stereotype.Service;import javax.annotation.Resource;
import java.util.ArrayList;
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;
import static com.hmdp.utils.RedisConstants.FEED_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 {@Resourceprivate IUserService userService;@Resourceprivate StringRedisTemplate stringRedisTemplate;@Resourceprivate IFollowService followService;@Overridepublic 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.isBlockLiked(blog);});return Result.ok(records);}@Overridepublic Result queryBlogById(Long id) {//1. 查询blogBlog 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isBlockLiked(blog);return Result.ok(blog);}private void isBlockLiked(Blog blog) {//1.获取登录用户UserDTO user = UserHolder.getUser();if(user == null){//用户未登录,无需查询是否点赞return;}//1.判断当前登录用户Long userId = UserHolder.getUser().getId();//2.判断当前登录用户是否已经点赞String key ="blog:liked:"+blog.getId();Double score = stringRedisTemplate.opsForZSet().score(key, userId.toString());blog.setIsLike(score != null);}@Overridepublic Result likeBlog(Long id) {//1.判断当前登录用户Long userId = UserHolder.getUser().getId();//2.判断当前登录用户是否已经点赞String key =BLOG_LIKED_KEY+id;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 +1boolean 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 -1boolean isSuccess = update().setSql("liked = liked + 1").eq("id", id).update();//4.2把用户从Redis的set集合移除if (isSuccess) {stringRedisTemplate.opsForZSet().remove(key, userId.toString());}}return Result.ok();}@Overridepublic Result queryBlogLikes(Long id) {String key =BLOG_LIKED_KEY + id;//1.查询top5的点赞用户 zrange key 0 4Set<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idList<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);}@Overridepublic 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idLong userId = follow.getUserId();//4.2推送String key = "feed:" + userId;stringRedisTemplate.opsForZSet().add(key,blog.getId().toString(),System.currentTimeMillis());}//5 返回idreturn Result.ok(blog.getId());}@Overridepublic Result queryBlogOfFollow(Long max, Integer offset) {//1.获取当前用户Long userId = UserHolder.getUser().getId();//2.查询收件箱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) offsetList<Long> ids =new ArrayList<>(typedTuples.size());long minTime =0;int os = 1;for(ZSetOperations.TypedTuple<String> tuple : typedTuples){//4.1 获取idids.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blogString 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isBlockLiked(blog);}//6 封装并返回ScrollResult r = new ScrollResult();r.setList(blogs);r.setOffset(os);r.setMinTime(minTime);return Result.ok(r);}private void queryBlogUser(Blog blog) {Long userId = blog.getUserId();User user = userService.getById(userId);blog.setName(user.getNickName());blog.setIcon(user.getIcon());}
}

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