1.显示评论

经典开发步骤，没有什么复杂的功能，就是查询出来的数据显示在前台页面上

数据层：

根据实体查询一页评论数据
根据实体查询评论的数量
业务层：
处理查询评论的业务
处理查询评论数量的业务
表现层：
显示帖子详情数据时，同时显示该帖子的所有评论
前台页面：
根据返回的对象，循环输出帖子评论、回复

这里只展示controller层的代码

@RequestMapping(value = "/detail/{discussPostId}", method = RequestMethod.GET)
    public String getDiscussPost(@PathVariable("discussPostId") int discussPostId, Model model, Page page) {
        //帖子
        DiscussPost post = discussPostService.findDiscussPostById(discussPostId);
        model.addAttribute("post", post);
        //作者
        User user = userService.findUserById(post.getUserId());
        model.addAttribute("user", user);

        //点赞
        long likeCount = likeService.findEntityLikeCount(ENTITY_TYPE_POST, discussPostId);
        model.addAttribute("likeCount", likeCount);
        //点赞状态
        int likeStatus = hostHolder.getUser() == null ? 0 : likeService.findEntityLikeStatus(hostHolder.getUser().getId(), ENTITY_TYPE_POST, discussPostId);
        model.addAttribute("likeStatus", likeStatus);

        //评论分页信息
        page.setLimit(5);
        page.setPath("/discuss/detail/" + discussPostId);
        page.setRows(post.getCommentCount());

        //评论：帖子的评论
        //回复：评论的评论
        //评论列表
        List<Comment> commentList = commentService.findCommentsByEntity(ENTITY_TYPE_POST, post.getId(), page.getOffset(), page.getLimit());

        //评论显示列表
        List<Map<String, Object>> commentVoList = new ArrayList<>();
        if (commentList != null) {
            for (Comment comment : commentList) {
                //评论Vo
                Map<String, Object> commentVo = new HashMap<>();
                //评论
                commentVo.put("comment", comment);
                //作者
                commentVo.put("user", userService.findUserById(comment.getUserId()));
                //目前还没开发点赞功能，下集更新
                //点赞
                likeCount = likeService.findEntityLikeCount(ENTITY_TYPE_COMMENT, comment.getId());
                commentVo.put("likeCount", likeCount);
                //点赞状态
                likeStatus = hostHolder.getUser() == null ? 0 : likeService.findEntityLikeStatus(hostHolder.getUser().getId(), ENTITY_TYPE_COMMENT, comment.getId());
                commentVo.put("likeStatus",likeStatus);

                //回复列表
                List<Comment> replyList = commentService.findCommentsByEntity(ENTITY_TYPE_COMMENT, comment.getId(), 0, Integer.MAX_VALUE);
                //回复Vo列表
                List<Map<String, Object>> replyVoList = new ArrayList<>();
                if (replyList != null) {
                    for (Comment reply : replyList) {
                        Map<String, Object> replayVo = new HashMap<>();
                        //回复
                        replayVo.put("reply", reply);
                        //回复的作者
                        replayVo.put("user", userService.findUserById(comment.getUserId()));
                        //回复目标
                        User target = reply.getTargetId() == 0 ? null : userService.findUserById(reply.getTargetId());
                        replayVo.put("target", target);

                        //点赞
                        likeCount = likeService.findEntityLikeCount(ENTITY_TYPE_COMMENT, reply.getId());
                        replayVo.put("likeCount",likeCount);
                        //点赞状态
                        likeStatus = hostHolder.getUser() == null ? 0 : likeService.findEntityLikeStatus(hostHolder.getUser().getId(), ENTITY_TYPE_COMMENT, reply.getId());
                        replayVo.put("likeStatus",likeStatus);

                        replyVoList.add(replayVo);
                    }
                }
                commentVo.put("replys", replyVoList);

                //回复数量
                int replyCount = commentService.findCommentCount(ENTITY_TYPE_COMMENT, comment.getId());
                commentVo.put("replyCount", replyCount);

                commentVoList.add(commentVo);
            }
        }
        model.addAttribute("comments", commentVoList);

        return "/site/discuss-detail";
    }

2.添加评论

也是经典开发步骤了，没难点
不过这里要注意的一点，因为要增加评论，提交的时候可能会出现些许问题，我们这里用声明式事务处理掉

数据层：

增加评论数据
修改帖子评论数量
业务层：
处理添加评论的业务-先增加评论、再更新帖子的评论数量
表现层：
处理添加评论数据的请求
设置添加评论的表单

这里展示业务层和表现层

    @Transactional(isolation = Isolation.READ_COMMITTED,propagation = Propagation.REQUIRED)
    public int addComment(Comment comment) {
        transactionTemplate.setIsolationLevel(TransactionDefinition.ISOLATION_READ_COMMITTED);
        transactionTemplate.setPropagationBehavior(TransactionDefinition.PROPAGATION_REQUIRED);
        if (comment == null) {
            throw new IllegalArgumentException("参数不能为空！");
        }

        comment.setContent(HtmlUtils.htmlEscape(comment.getContent()));
        comment.setContent(sensitiveFilter.filter(comment.getContent()));

        int rows = commentMapper.insertComment(comment);

        //更新帖子评论数量
        if (comment.getEntityType() == ENTITY_TYPE_POST) {
            int count = commentMapper.selectCountByEntity(comment.getEntityType(), comment.getEntityId());
            discussPostService.updateCommentCount(comment.getEntityId(), count);
        }

        return rows;
    }

@RequestMapping(value = "/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) {
            int userId = discussPostService.findDiscussPostById(comment.getEntityId()).getUserId();
            event.setEntityUserId(userId);
        }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){
            event = new Event()
                    .setTopic(TOPIC_PUBLISH)
                    .setUserId(hostHolder.getUser().getId())
                    .setEntityId(discussPostId)
                    .setEntityType(ENTITY_TYPE_POST);
            eventProducer.fireEvent(event);

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



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

问答社区-显示、添加评论

1.显示评论

2.添加评论