（仿牛客社区项目）Java开发笔记7.6：热帖排行

热帖排行

1.util包

RedisKeyUtil类添加相关键。

package com.gerrard.community.util;

public class RedisKeyUtil {

    private static final String PREFIX_POST = "post";

   //帖子分数 post:score->【需要重新计算分数的帖子id集合】
    public static String getPostScoreKey(){
        return PREFIX_POST+SPLIT+"score";
    }

}

2.dao层

DiscussPostMapper类中添加updateScore方法，重构selectDiscussPosts方法,方法中添加orderMode字段。

package com.gerrard.community.dao;

import com.gerrard.community.entity.DiscussPost;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;

import java.util.List;

@Mapper
public interface DiscussPostMapper {

    List<DiscussPost> selectDiscussPosts(int userId, int offset, int limit, int orderMode);

    // @Param注解用于给参数取别名,
    // 如果只有一个参数,并且在里使用,则必须加别名.
    int selectDiscussPostRows(@Param("userId") int userId);

    int insertDiscussPost(DiscussPost discussPost);

    DiscussPost selectDiscussPostById(int id);

    int updateCommentCount(int id, int commentCount);

    int updateType(int id, int type);

    int updateStatus(int id, int status);

    int updateScore(int id, double score);

}

discusspost-mapper.xml：

DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.gerrard.community.dao.DiscussPostMapper">

    <sql id="selectFields">
        id, user_id, title, content, type, status, create_time, comment_count, score
    sql>

    <sql id="insertFields">
        user_id, title, content, type, status, create_time, comment_count, score
    sql>

    <select id="selectDiscussPosts" resultType="DiscussPost">
        select <include refid="selectFields">include>
        from discuss_post
        where status != 2
        <if test="userId!=0">
            and user_id = #{userId}
        if>
        <if test="orderMode==0">
            order by type desc, create_time desc
        if>
        <if test="orderMode==1">
            order by type desc, score desc, create_time desc
        if>
        limit #{offset}, #{limit}
    select>


    <update id="updateScore">
        update discuss_post set score = #{score} where id = #{id}
    update>

mapper>

3.service层

DiscussPostService类中重构findDiscussPosts方法，DiscussPostService类中添加updateScore方法。

package com.gerrard.community.service;

import com.gerrard.community.dao.DiscussPostMapper;
import com.gerrard.community.entity.DiscussPost;
import com.gerrard.community.util.SensitiveFilter;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.web.util.HtmlUtils;

import java.util.List;

@Service
public class DiscussPostService {

    @Autowired
    private DiscussPostMapper discussPostMapper;

    @Autowired
    private SensitiveFilter sensitiveFilter;

    public List<DiscussPost> findDiscussPosts(int userId, int offset, int limit, int orderMode) {
        return discussPostMapper.selectDiscussPosts(userId, offset, limit, orderMode);
    }

    public int updateScore(int id, double score) {
        return discussPostMapper.updateScore(id, score);
    }

}

4.controller层

（1）DiscusspostController类：发帖，加精方法添加“计算帖子分数”代码。

package com.gerrard.community.controller;

import com.gerrard.community.entity.*;
import com.gerrard.community.event.EventProducer;
import com.gerrard.community.service.CommentService;
import com.gerrard.community.service.DiscussPostService;
import com.gerrard.community.service.LikeService;
import com.gerrard.community.service.UserService;
import com.gerrard.community.util.CommunityConstant;
import com.gerrard.community.util.CommunityUtil;
import com.gerrard.community.util.HostHolder;
import com.gerrard.community.util.RedisKeyUtil;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;

import java.util.*;

@Controller
@RequestMapping("/discuss")
public class DiscussPostController implements CommunityConstant {

    @Autowired
    private DiscussPostService discussPostService;

    @Autowired
    private HostHolder hostHolder;

    @Autowired
    private UserService userService;

    @Autowired
    private CommentService commentService;

    @Autowired
    private LikeService likeService;

    @Autowired
    private EventProducer eventProducer;

    @Autowired
    private RedisTemplate redisTemplate;

    @RequestMapping(path = "/add", method = RequestMethod.POST)
    @ResponseBody
    public String addDiscussPost(String title, String content) {
        User user = hostHolder.getUser();
        if (user == null) {
            return CommunityUtil.getJSONString(403, "你还没有登录哦!");
        }

        DiscussPost post = new DiscussPost();
        post.setUserId(user.getId());
        post.setTitle(title);
        post.setContent(content);
        post.setCreateTime(new Date());
        discussPostService.addDiscussPost(post);

        // 触发发帖事件
        Event event = new Event()
                .setTopic(TOPIC_PUBLISH)
                .setUserId(user.getId())
                .setEntityType(ENTITY_TYPE_POST)
                .setEntityId(post.getId());
        eventProducer.fireEvent(event);

        // 计算帖子分数
        String redisKey = RedisKeyUtil.getPostScoreKey();
        redisTemplate.opsForSet().add(redisKey, post.getId());

        // 报错的情况,将来统一处理.
        return CommunityUtil.getJSONString(0, "发布成功!");
    }

    // 置顶
    @RequestMapping(path = "/top", method = RequestMethod.POST)
    @ResponseBody
    public String setTop(int id) {
        discussPostService.updateType(id, 1);

        // 触发发帖事件
        Event event = new Event()
                .setTopic(TOPIC_PUBLISH)
                .setUserId(hostHolder.getUser().getId())
                .setEntityType(ENTITY_TYPE_POST)
                .setEntityId(id);
        eventProducer.fireEvent(event);

        return CommunityUtil.getJSONString(0);
    }

    // 加精
    @RequestMapping(path = "/wonderful", method = RequestMethod.POST)
    @ResponseBody
    public String setWonderful(int id) {
        discussPostService.updateStatus(id, 1);

        // 触发发帖事件
        Event event = new Event()
                .setTopic(TOPIC_PUBLISH)
                .setUserId(hostHolder.getUser().getId())
                .setEntityType(ENTITY_TYPE_POST)
                .setEntityId(id);
        eventProducer.fireEvent(event);

        // 计算帖子分数
        String redisKey = RedisKeyUtil.getPostScoreKey();
        redisTemplate.opsForSet().add(redisKey, id);

        return CommunityUtil.getJSONString(0);
    }

    // 删除
    @RequestMapping(path = "/delete", method = RequestMethod.POST)
    @ResponseBody
    public String setDelete(int id) {
        discussPostService.updateStatus(id, 2);

        // 触发删帖事件
        Event event = new Event()
                .setTopic(TOPIC_DELETE)
                .setUserId(hostHolder.getUser().getId())
                .setEntityType(ENTITY_TYPE_POST)
                .setEntityId(id);
        eventProducer.fireEvent(event);

        return CommunityUtil.getJSONString(0);
    }

}

（2）CommentController类：addComment方法添加“计算帖子分数”代码。

package com.gerrard.community.controller;

import com.gerrard.community.entity.Comment;
import com.gerrard.community.entity.DiscussPost;
import com.gerrard.community.entity.Event;
import com.gerrard.community.event.EventProducer;
import com.gerrard.community.service.CommentService;
import com.gerrard.community.service.DiscussPostService;
import com.gerrard.community.util.CommunityConstant;
import com.gerrard.community.util.HostHolder;
import com.gerrard.community.util.RedisKeyUtil;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;

import java.util.Date;

@Controller
@RequestMapping("/comment")
public class CommentController implements CommunityConstant {

    @Autowired
    private CommentService commentService;

    @Autowired
    private HostHolder hostHolder;

    @Autowired
    private EventProducer eventProducer;

    @Autowired
    private DiscussPostService discussPostService;

    @Autowired
    private RedisTemplate redisTemplate;

    @RequestMapping(path = "/add/{discussPostId}", method = RequestMethod.POST)
    public String addComment(@PathVariable("discussPostId") int discussPostId, Comment comment) {
        comment.setUserId(hostHolder.getUser().getId());
        comment.setStatus(0);
        comment.setCreateTime(new Date());
        commentService.addComment(comment);

        // 触发评论事件
        Event event = new Event()
                .setTopic(TOPIC_COMMENT)
                .setUserId(hostHolder.getUser().getId())
                .setEntityType(comment.getEntityType())
                .setEntityId(comment.getEntityId())
                .setData("postId", discussPostId);
        if (comment.getEntityType() == ENTITY_TYPE_POST) {
            DiscussPost target = discussPostService.findDiscussPostById(comment.getEntityId());
            event.setEntityUserId(target.getUserId());
        } else if (comment.getEntityType() == ENTITY_TYPE_COMMENT) {
            Comment target = commentService.findCommentById(comment.getEntityId());
            event.setEntityUserId(target.getUserId());
        }
        eventProducer.fireEvent(event);

        if (comment.getEntityType() == ENTITY_TYPE_POST) {
            // 触发发帖事件
            event = new Event()
                    .setTopic(TOPIC_PUBLISH)
                    .setUserId(comment.getUserId())
                    .setEntityType(ENTITY_TYPE_POST)
                    .setEntityId(discussPostId);
            eventProducer.fireEvent(event);
            // 计算帖子分数
            String redisKey = RedisKeyUtil.getPostScoreKey();
            redisTemplate.opsForSet().add(redisKey, discussPostId);
        }

        return "redirect:/discuss/detail/" + discussPostId;
    }

}

（3）LikeController类：like方法添加“计算帖子分数”代码。

package com.gerrard.community.controller;

import com.gerrard.community.entity.Event;
import com.gerrard.community.entity.User;
import com.gerrard.community.event.EventProducer;
import com.gerrard.community.service.LikeService;
import com.gerrard.community.util.CommunityConstant;
import com.gerrard.community.util.CommunityUtil;
import com.gerrard.community.util.HostHolder;
import com.gerrard.community.util.RedisKeyUtil;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;

import java.util.HashMap;
import java.util.Map;

@Controller
public class LikeController implements CommunityConstant {

    @Autowired
    private LikeService likeService;

    @Autowired
    private HostHolder hostHolder;

    @Autowired
    private EventProducer eventProducer;

    @Autowired
    private RedisTemplate redisTemplate;

    @RequestMapping(path = "/like", method = RequestMethod.POST)
    @ResponseBody
    public String like(int entityType, int entityId, int entityUserId, int postId) {
        User user = hostHolder.getUser();

        // 点赞
        likeService.like(user.getId(), entityType, entityId, entityUserId);

        // 数量
        long likeCount = likeService.findEntityLikeCount(entityType, entityId);
        // 状态
        int likeStatus = likeService.findEntityLikeStatus(user.getId(), entityType, entityId);
        // 返回的结果
        Map<String, Object> map = new HashMap<>();
        map.put("likeCount", likeCount);
        map.put("likeStatus", likeStatus);

        // 触发点赞事件
        if (likeStatus == 1) {
            Event event = new Event()
                    .setTopic(TOPIC_LIKE)
                    .setUserId(hostHolder.getUser().getId())
                    .setEntityType(entityType)
                    .setEntityId(entityId)
                    .setEntityUserId(entityUserId)
                    .setData("postId", postId);
            eventProducer.fireEvent(event);
        }

        if(entityType == ENTITY_TYPE_POST) {
            // 计算帖子分数
            String redisKey = RedisKeyUtil.getPostScoreKey();
            redisTemplate.opsForSet().add(redisKey, postId);
        }

        return CommunityUtil.getJSONString(0, null, map);
    }

}

（4）HomeController类中修改getIndexPage方法，添加orderMode字段。

package com.gerrard.community.controller;

import com.gerrard.community.entity.DiscussPost;
import com.gerrard.community.entity.Page;
import com.gerrard.community.entity.User;
import com.gerrard.community.service.DiscussPostService;
import com.gerrard.community.service.LikeService;
import com.gerrard.community.service.UserService;
import com.gerrard.community.util.CommunityConstant;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

@Controller
public class HomeController implements CommunityConstant {

    @Autowired
    private DiscussPostService discussPostService;

    @Autowired
    private UserService userService;

    @Autowired
    private LikeService likeService;

    @RequestMapping(path = "/index", method = RequestMethod.GET)
    public String getIndexPage(Model model, Page page,
                               @RequestParam(name = "orderMode", defaultValue = "0") int orderMode) {
        // 方法调用钱,SpringMVC会自动实例化Model和Page,并将Page注入Model.
        // 所以,在thymeleaf中可以直接访问Page对象中的数据.
        page.setRows(discussPostService.findDiscussPostRows(0));
        page.setPath("/index?orderMode=" + orderMode);

        List<DiscussPost> list = discussPostService
                .findDiscussPosts(0, page.getOffset(), page.getLimit(), orderMode);
        List<Map<String, Object>> discussPosts = new ArrayList<>();
        if (list != null) {
            for (DiscussPost post : list) {
                Map<String, Object> map = new HashMap<>();
                map.put("post", post);
                User user = userService.findUserById(post.getUserId());
                map.put("user", user);

                long likeCount = likeService.findEntityLikeCount(ENTITY_TYPE_POST, post.getId());
                map.put("likeCount", likeCount);

                discussPosts.add(map);
            }
        }
        model.addAttribute("discussPosts", discussPosts);
        model.addAttribute("orderMode", orderMode);

        return "/index";
    }

    @RequestMapping(path = "/error", method = RequestMethod.GET)
    public String getErrorPage() {
        return "/error/500";
    }

    @RequestMapping(path = "/denied", method = RequestMethod.GET)
    public String getDeniedPage() {
        return "/error/404";
    }
}

5.config包

在QuartzConfig类中新配置刷新帖子分数任务。

package com.gerrard.community.config;

import com.gerrard.community.quartz.AlphaJob;
import com.gerrard.community.quartz.PostScoreRefreshJob;
import org.quartz.JobDataMap;
import org.quartz.JobDetail;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.scheduling.quartz.JobDetailFactoryBean;
import org.springframework.scheduling.quartz.SimpleTriggerFactoryBean;

// 配置 -> 数据库 -> 调用
@Configuration
public class QuartzConfig {

    // FactoryBean可简化Bean的实例化过程:
    // 1.通过FactoryBean封装Bean的实例化过程.
    // 2.将FactoryBean装配到Spring容器里.
    // 3.将FactoryBean注入给其他的Bean.
    // 4.该Bean得到的是FactoryBean所管理的对象实例.

    // 配置JobDetail
    // @Bean
    public JobDetailFactoryBean alphaJobDetail() {
        JobDetailFactoryBean factoryBean = new JobDetailFactoryBean();
        factoryBean.setJobClass(AlphaJob.class);
        factoryBean.setName("alphaJob");
        factoryBean.setGroup("alphaJobGroup");
        factoryBean.setDurability(true);
        factoryBean.setRequestsRecovery(true);
        return factoryBean;
    }

    // 配置Trigger(SimpleTriggerFactoryBean, CronTriggerFactoryBean)
    // @Bean
    public SimpleTriggerFactoryBean alphaTrigger(JobDetail alphaJobDetail) {
        SimpleTriggerFactoryBean factoryBean = new SimpleTriggerFactoryBean();
        factoryBean.setJobDetail(alphaJobDetail);
        factoryBean.setName("alphaTrigger");
        factoryBean.setGroup("alphaTriggerGroup");
        factoryBean.setRepeatInterval(3000);
        factoryBean.setJobDataMap(new JobDataMap());
        return factoryBean;
    }

    // 刷新帖子分数任务
    @Bean
    public JobDetailFactoryBean postScoreRefreshJobDetail() {
        JobDetailFactoryBean factoryBean = new JobDetailFactoryBean();
        factoryBean.setJobClass(PostScoreRefreshJob.class);
        factoryBean.setName("postScoreRefreshJob");
        factoryBean.setGroup("communityJobGroup");
        factoryBean.setDurability(true);
        factoryBean.setRequestsRecovery(true);
        return factoryBean;
    }

    @Bean
    public SimpleTriggerFactoryBean postScoreRefreshTrigger(JobDetail postScoreRefreshJobDetail) {
        SimpleTriggerFactoryBean factoryBean = new SimpleTriggerFactoryBean();
        factoryBean.setJobDetail(postScoreRefreshJobDetail);
        factoryBean.setName("postScoreRefreshTrigger");
        factoryBean.setGroup("communityTriggerGroup");
        factoryBean.setRepeatInterval(1000 * 60 * 5);
        factoryBean.setJobDataMap(new JobDataMap());
        return factoryBean;
    }

}

6.quartz包

在quarz包下新建PostScoreRefreshJob类。

package com.gerrard.community.quartz;

import com.gerrard.community.entity.DiscussPost;
import com.gerrard.community.service.DiscussPostService;
import com.gerrard.community.service.ElasticsearchService;
import com.gerrard.community.service.LikeService;
import com.gerrard.community.util.CommunityConstant;
import com.gerrard.community.util.RedisKeyUtil;
import org.quartz.Job;
import org.quartz.JobExecutionContext;
import org.quartz.JobExecutionException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.BoundSetOperations;
import org.springframework.data.redis.core.RedisTemplate;

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;

public class PostScoreRefreshJob implements Job, CommunityConstant {

    private static final Logger logger = LoggerFactory.getLogger(PostScoreRefreshJob.class);

    @Autowired
    private RedisTemplate redisTemplate;

    @Autowired
    private DiscussPostService discussPostService;

    @Autowired
    private LikeService likeService;

    @Autowired
    private ElasticsearchService elasticsearchService;

    // 牛客纪元
    private static final Date epoch;

    static {
        try {
            epoch = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").parse("2014-08-01 00:00:00");
        } catch (ParseException e) {
            throw new RuntimeException("初始化牛客纪元失败!", e);
        }
    }

    @Override
    public void execute(JobExecutionContext context) throws JobExecutionException {
        String redisKey = RedisKeyUtil.getPostScoreKey();
        BoundSetOperations operations = redisTemplate.boundSetOps(redisKey);

        if (operations.size() == 0) {
            logger.info("[任务取消] 没有需要刷新的帖子!");
            return;
        }

        logger.info("[任务开始] 正在刷新帖子分数: " + operations.size());
        while (operations.size() > 0) {
            this.refresh((Integer) operations.pop());
        }
        logger.info("[任务结束] 帖子分数刷新完毕!");
    }

    private void refresh(int postId) {
        DiscussPost post = discussPostService.findDiscussPostById(postId);

        if (post == null) {
            logger.error("该帖子不存在: id = " + postId);
            return;
        }

        // 是否精华
        boolean wonderful = post.getStatus() == 1;
        // 评论数量
        int commentCount = post.getCommentCount();
        // 点赞数量
        long likeCount = likeService.findEntityLikeCount(ENTITY_TYPE_POST, postId);

        // 计算权重
        double w = (wonderful ? 75 : 0) + commentCount * 10 + likeCount * 2;
        // 分数 = 帖子权重 + 距离天数
        double score = Math.log10(Math.max(w, 1))
                + (post.getCreateTime().getTime() - epoch.getTime()) / (1000 * 3600 * 24);
        // 更新帖子分数
        discussPostService.updateScore(postId, score);
        // 同步搜索数据
        post.setScore(score);
        elasticsearchService.saveDiscussPost(post);
    }

}

7. view层

修改index.html页面。

8.功能分析

8.1 将需要更新分数的帖子添加到Redis数据库中

用户发帖；版主加精；用户评论，用户点赞【都是针对帖子】,将帖子id添加到Redis数据库中。

		// 计算帖子分数
        String redisKey = RedisKeyUtil.getPostScoreKey();
        redisTemplate.opsForSet().add(redisKey, post.getId());

		//post:score->【需要重新计算分数的帖子id集合】

8.2 借助quartz更新帖子分数

每隔5分钟执行PostScoreRefreshJob类中的refresh方法：

1.查看Redis数据库中post:score键中是否存有帖子id，没有则结束；

2.如果存有帖子id集合，则pop遍历集合，对每个帖子计算对应指标，算出帖子的分数，再更新帖子的分数。

8.3 主页按热度查看帖子

在index主页点击最热按钮，则帖子展示顺序为帖子种类，帖子得分，帖子创建时间。

		<if test="orderMode==0">
            order by type desc, create_time desc
        if>
        <if test="orderMode==1">
            order by type desc, score desc, create_time desc
        if>

9.功能测试

进行加精操作：

查看Redis数据库：

更新分数：

再次查看Redis数据库：

查看主页：