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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