问答社区-显示、添加评论
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;
}
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