最近实现了评论和回复、点赞、@的功能。在这里分享一下我的设计思路（先分享评论和回复功能）。希望各位读者给出一些不一样的建议后期改进。

效果展示

总共是两层回复 （回复评论、回复评论下的回复）

数据库设计

评论表（TFW_Comments）和回复内容表（TFW_UserResponse）以及评论回复关系表（TFW_MsgRelation）

 数据库设计思路：

注：各位读者自动忽略评论表的服务机构ID字段，这个字段相当于这条评论是在哪个帖子（文章下面）

1、根据文章ID或者是帖子ID查询评论表获取评论（本文的服务机构ID）。第一层（评论）

2、根据评论ID并且回复类型等于1的去关系表获取第二层的回复（commentsId）。第二层（评论下的回复）

3、根据评论ID、回复类型等于2、回复ID去关系表获取第三层回复。第三层（评论下回复中的回复）注：回复ID是它的上级

实现类源码

@Override
    public Map<String, Object> findComments(JSONObject jsonObject) {
        data.clear();
        String userId = jsonObject.getString("userId");

        String role = this.role(jsonObject);
        if (role.equals("-1")){
            //没有权限
            data.put("error","-1");
            data.put("msg","当前用户没有权限");
            return data;
        }

        List<Map<String, Object>> info = commentsDao.findComment(jsonObject.getString("fWJLID"),null);
        //查询点赞次数
        int countTag = 0;
        MsgRelationTag msgRelationTag = new MsgRelationTag();

        for (Map item : info){
            item.put("inputShow",false);
            int commentsId = (int) item.get("commentsId");
            //查询点赞次数
             countTag = msgRelationDao.findCountTagByTagId(commentsId,1);
            item.put("countTag",countTag);
            //设置点赞状态
            msgRelationTag.setTagId(commentsId);
            msgRelationTag.setTagType(1);
            msgRelationTag.setTagUserId(Integer.parseInt(userId));
            MsgRelationTag msgTag = msgRelationDao.findMsgTag(msgRelationTag);
            if (msgTag != null) {
                item.put("tagStatus",msgTag.getStatus());
            }else {
                item.put("tagStatus","");
            }
            //如果有@id
            if (item.get("atId") != null){
                String content = item.get("content").toString();
                StringBuffer tmrAtId = findUserName(item.get("atId").toString());
                item.put("content",content+'@'+tmrAtId);
            }
            //二级回复数据
            List<Map<String, Object>> twoReply = new ArrayList<>();
            //所有数据
            List<Map<String, Object>> userResponse = userResponseDao.findUserResponse(commentsId, null, "","",null);
            for (Map userResponseInfo :userResponse){
                int userResponseIds = Integer.parseInt(userResponseInfo.get("userResponseId").toString());
                //查询点赞次数
                countTag = msgRelationDao.findCountTagByTagId(userResponseIds,2);
                //设置点赞状态
                msgRelationTag.setTagId(userResponseIds);
                msgRelationTag.setTagType(2);
                msgTag = msgRelationDao.findMsgTag(msgRelationTag);
                if (msgTag != null) {userResponseInfo.put("tagStatus",msgTag.getStatus());}else {userResponseInfo.put("tagStatus","");}
                userResponseInfo.put("countTag",countTag);
                userResponseInfo.put("inputShow",false);
                Integer responseType = (Integer) userResponseInfo.get("responseType");
                for (Map stairReplyInfo : userResponse){
                    Integer  userResponseId = (Integer) stairReplyInfo.get("userResponseId");
                    int msgRelationId = Integer.parseInt(stairReplyInfo.get("msgRelationId").toString());
                    //接受者id*/
                    twoReply = userResponseDao.findUserResponse(msgRelationId, userResponseId,"1","",null); //二级回复数据
                    for (Map twoReplyItem : twoReply){
                        int twoReplyId = Integer.parseInt(twoReplyItem.get("userResponseId").toString());
                        twoReplyItem.put("inputShow",false);
                        //查询点赞次数
                        countTag = msgRelationDao.findCountTagByTagId(twoReplyId,2);
                        twoReplyItem.put("countTag",countTag);
                        //设置点赞状态
                        msgRelationTag.setTagId(twoReplyId);
                        msgTag = msgRelationDao.findMsgTag(msgRelationTag);
                        if (msgTag != null) {twoReplyItem.put("tagStatus",msgTag.getStatus());}else {twoReplyItem.put("tagStatus","");}
                        String userRepContent = twoReplyItem.get("userRepContent").toString();
                        if (twoReplyItem.get("tmrAtId") != null){
                            StringBuffer tmrAtId = findUserName(twoReplyItem.get("tmrAtId").toString());
                            twoReplyItem.put("userRepContent",userRepContent+'@'+tmrAtId);
                        }

                    }
                    stairReplyInfo.put("twoReply",twoReply);
                }
            }
            item.put("stairReply",userResponse);
        }
        data.put("data",info);
        data.put("error",0);
        data.put("msg","查询成功");
        return data;
    }

其它的代码可以忽略。主要语句有：

获取帖子下的评论

 List<Map<String, Object>> info = commentsDao.findComment(jsonObject.getString("fWJLID"),null);

上图根据FWJLID获取评论。（此处可以当成帖子的ID，获取帖子下的评论）一级展示

对应SQL语句（OPT是我的用户表）

select tc.content ,tc.commentsId,convert(varchar(19),tc.startTime,120) as startTime,tc.recipientId ,tc.operatorId,zo.NAME as operatorName,tc.atId,zo.HeadImgUrl as operatorHeadImgUrl
         from TFW_Comments tc
         left join zd_opt zo on zo.AID = tc.operatorId where tc.FWJLID = 5101

查询结果：

 获取评论下的回复

List<Map<String, Object>> userResponse = userResponseDao.findUserResponse(commentsId, null, "","",null);

上图根据commentsid获取评论下的回复。（根据评论ID获取回复）二级展示

对应sql语句

select
 	 tur.userResponseId,tur.operatorId,tur.recipientId,convert(varchar(19),tur.startTime,120) as startTime,tur.userRepContent,tmr.atId as tmrAtId,
 	 tmr.msgRelationId ,tmr.responseType,tmr.replyId,
        zo.NAME as operatorName,
        zo1.NAME as recipientName,
        zo.HeadImgUrl as operatorHeadImgUrl,
        zo1.HeadImgUrl as recipientHeadImgUrl
        from TFW_MsgRelation tmr
        left join TFW_UserResponse tur on tur.userResponseId = tmr.userResponseId
        left join zd_opt zo on zo.AID = tur.operatorId
        left join zd_opt zo1 on zo1.AID = tur.recipientId where tmr.commentsId = 47

查询结果

 获取二级回复

 twoReply = userResponseDao.findUserResponse(msgRelationId, userResponseId,"1","",null); //二级回复数据

上图是根据评论ID（msgRelationId）和回复ID（userResponseId）去获取二级回复。回复ID也就是父类。就是回复那一条回复的ID。 第三层展示

对应sql

select
 	 tur.userResponseId,tur.operatorId,tur.recipientId,convert(varchar(19),tur.startTime,120) as startTime,tur.userRepContent,tmr.atId as tmrAtId,
 	 tmr.msgRelationId ,tmr.responseType,tmr.replyId,
        zo.NAME as operatorName,
        zo1.NAME as recipientName,
        zo.HeadImgUrl as operatorHeadImgUrl,
        zo1.HeadImgUrl as recipientHeadImgUrl
        from TFW_MsgRelation tmr
        left join TFW_UserResponse tur on tur.userResponseId = tmr.userResponseId
        left join zd_opt zo on zo.AID = tur.operatorId
        left join zd_opt zo1 on zo1.AID = tur.recipientId where tmr.commentsId = 136 and tmr.replyId = 155

查询结果

返回页面展示和返回体展示