仿牛客网社区项目（三十四）热榜

热榜

• Spring Quartz（将数据存储到数据库，分布式时可以共享数据）

  • 核心调度接口Scheduler
  • 定义任务的接口Job的execute方法
  • Jobdetail接口来配置Job的名字、组等
  • Trigger接口配置Job的什么时候运行、运行频率
  • QuartzConfig：配置 -> 数据库 -> 调用

• 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.

7. 热帖排行#

• Nowcoder

  • log(精华分 + 评论数 * 10 + 点赞数 * 2)+（发布时间 - 牛客纪元）
  • 在发帖、点赞、加精时计算帖子分数（存入Redis中）
  • 新建PostScoreRefreshJob类进行处理

添加依赖 增加定时任务

<!--quartz依赖--->
<dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-quartz</artifactId>
 </dependency>

yml配置

spring:
  quartz:
    #相关属性配置
    properties:
      org:
        quartz:
          scheduler:
            instanceName: communityScheduler
            instanceId: AUTO
          jobStore:
            class: org.quartz.impl.jdbcjobstore.JobStoreTX
            driverDelegateClass: org.quartz.impl.jdbcjobstore.StdJDBCDelegate
            tablePrefix: QRTZ_
            isClustered: true
            clusterCheckinInterval: 10000
            useProperties: false
          threadPool:
            class: org.quartz.simpl.SimpleThreadPool
            threadCount: 10
            threadPriority: 5
            threadsInheritContextClassLoaderOfInitializingThread: true
    #数据库方式
    job-store-type: jdbc
    #初始化表结构
    #jdbc:
      #initialize-schema: never

拼接Redis key

private static final String PREFIX_POST = "post";
// 帖子分数
public static String getPostScoreKey() {
    return PREFIX_POST + SPLIT + "score";
}

DiscusspostController. add

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

jiajing

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

comment.add

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

like like

//只有对帖子点赞才算分数
if(entityType == ENTITY_TYPE_POST) {
            // 计算帖子分数
            String redisKey = RedisKeyUtil.getPostScoreKey();
            redisTemplate.opsForSet().add(redisKey, postId);
        }

定时任务

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);
    }

}

配置config

// 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.
    // 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;
    }

    // 配置JobDetail
    // 配置Trigger(SimpleTriggerFactoryBean, CronTriggerFactoryBean)
    // @Bean

    @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;
    }