Java单表实现评论回复功能
- 1.简介
- 2.功能实现图
- 3.数据库设计
- 4.实体类
- 5.实现思路
- 6.功能实现
- 6.1 Sql入手
- 6.2 业务实现
- 7.前端实现
- 8.最终成果
1.简介
最近在写毕业设计的时候发现需要实现一个评论功能,然后看了一下掘金和csdn的评论区,如何实现评论功能?
评论功能有多种实现方式:
- 单层型
- 套娃型(多层型)
- 两层型
单层型:
套娃型:
两层型:
2.功能实现图
3.数据库设计
这个地方有个answer_id 很容易让人迷糊:是回复哪个用户的id
CREATE TABLE `tb_blog_comments`(`id` bigint(20) UNSIGNED NOT NULL AUTO_INCREMENT COMMENT '主键',`user_id` bigint(20) UNSIGNED NOT NULL COMMENT '用户id',`blog_id` bigint(20) UNSIGNED NOT NULL COMMENT '探店id',`parent_id` bigint(20) UNSIGNED NOT NULL COMMENT '关联的1级评论id,如果是一级评论,则值为0',`answer_id` bigint(20) UNSIGNED NOT NULL COMMENT '回复的评论id',`content` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NOT NULL COMMENT '回复的内容',`liked` int(8) UNSIGNED NULL DEFAULT 0 COMMENT '点赞数',`status` tinyint(1) UNSIGNED NULL DEFAULT 0 COMMENT '状态,0:正常,1:被举报,2:禁止查看',`create_time` timestamp(0) NOT NULL DEFAULT CURRENT_TIMESTAMP(0) COMMENT '创建时间',`update_time` timestamp(0) NOT NULL DEFAULT CURRENT_TIMESTAMP(0) ON UPDATE CURRENT_TIMESTAMP(0) COMMENT '更新时间',PRIMARY KEY (`id`) USING BTREE) ENGINE = InnoDB CHARACTER SET = utf8mb4 COLLATE = utf8mb4_general_ci ROW_FORMAT = COMPACT;SET FOREIGN_KEY_CHECKS = 1;
4.实体类
import com.baomidou.mybatisplus.annotation.IdType;import com.baomidou.mybatisplus.annotation.TableField;import com.baomidou.mybatisplus.annotation.TableId;import com.baomidou.mybatisplus.annotation.TableName;import com.fasterxml.jackson.annotation.JsonFormat;import lombok.Data;import lombok.EqualsAndHashCode;import lombok.experimental.Accessors;import java.io.Serializable;import java.time.LocalDateTime;import java.util.List;/** * **
* * @author 尹稳健 * @since 2022-11-09 */@Data@EqualsAndHashCode(callSuper = false)@Accessors(chain = true)@TableName("tb_blog_comments")public class BlogComments implements Serializable {private static final long serialVersionUID = 1L;/** * 主键 */@TableId(value = "id", type = IdType.AUTO)private Long id;/** * 用户id */private Long userId;/** * 探店id */private Long blogId;/** * 关联的1级评论id,如果是一级评论,则值为0 */private Long parentId;/** * 回复的评论id */private Long answerId;/** * 回复的内容 */private String content;/** * 点赞数 */private Integer liked;/** * 状态,0:正常,1:被举报,2:禁止查看 */private Boolean status;/** * 创建时间 */@JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")private LocalDateTime createTime;/** * 更新时间 */private LocalDateTime updateTime;/** * 是否点赞 */@TableField(exist = false)private Boolean isLike;/** * 子评论 */@TableField(exist = false)List<BlogComments> children;/** * 评论者的昵称 */@TableField(exist = false)private String nickName;/** 评论者的头像 */@TableField(exist = false)private String icon;/** 评论者的上级昵称 */@TableField(exist = false)private String pNickName;/** 评论者的的上级头像 */@TableField(exist = false)private String pIcon;}
5.实现思路
- 因为有评论区有两层,所以肯定有一个parent_id,这样你才能知道你是哪个评论下面的回复内容,如果继续评论,那么那条评论的parent_id还是之前那条评论的parent_id,而不是那条子评论的id。
- 回复内容也同样是一个评论实体类,只不过是一个集合,所以用List 存储,泛型使用实体类
- 我的功能实现也用到了父评论的用户名和头像,这样可以更好看出这是谁评论的,回复给谁的评论
6.功能实现
6.1 Sql入手
首先,我们需要知道自己需要哪些数据,返回给前端
如果你连mybatis都不会,那就看下思路吧
从这里获取到了评论表的所有数据,以及评论的人的信息,比如说昵称、头像、id,可以展示在前端
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" ><mapper namespace="com.sky.mapper.BlogCommentsMapper"><select id="findCommentDetail" resultType="com.sky.pojo.BlogComments">SELECTbl.*,u.icon,u.nick_nameFROM `tb_blog_comments` blleft join tb_user uon u.id = bl.user_idwhere bl.blog_id = #{blogId}order by bl.id desc</select></mapper>
对应的mapper接口
package com.sky.mapper;import com.baomidou.mybatisplus.core.mapper.BaseMapper;import com.sky.pojo.BlogComments;import org.apache.ibatis.annotations.Mapper;import java.util.List;/** * *Mapper 接口 *
* * @author 尹稳健 * @since 2022-11-09 */@Mapperpublic interface BlogCommentsMapper extends BaseMapper<BlogComments> {/** * 查询所有的评论信息 * @param blogId * @return */List<BlogComments> findCommentDetail(Long blogId);}
6.2 业务实现
- 1.首先我们需要从数据中获取所有的数据
- 2.然后我们需要找到所有的一级评论,一级评论就是最高级,他不在谁的下面,他就是最大的,我这里在添加评论的时候前端做了处理,只要是一级评论,他的paren_id = 0
- 3.然后我们需要从一级评论下面添加他下面所有的子评论
- 最主要的就是如何将父级评论的信息添加到自己的数据中?
- 4.通过子评论中的paren_id 找到父评论,然后通过子评论的answer_id == 父评论的user_id 这样就可以拿到父评论的那一条数据
- 最后通过Optional 添加到子评论的数据中
@Overridepublic Result showBlogComments(Long blogId) {// 先将数据库中的数据全部查询出来,包括评论作者的信息,昵称和头像List<BlogComments> blogComments = blogCommentsMapper.findCommentDetail(blogId);// 获取所有的一级评论List<BlogComments> rootComments = blogComments.stream().filter(blogComments1 -> blogComments1.getParentId() == 0).collect(Collectors.toList());// 从一级评论中获取回复评论for (BlogComments rootComment : rootComments) {// 回复的评论List<BlogComments> comments = blogComments.stream().filter(blogComment -> blogComment.getParentId().equals(rootComment.getId())).collect(Collectors.toList());// 回复评论中含有父级评论的信息comments.forEach(comment -> {// 无法判断pComment是否存在,可以使用OptionalOptional<BlogComments> pComment= blogComments.stream()// 获取所有的评论的回复id也就是父级id的userid,这样就可以获取到父级评论的信息.filter(blogComment -> comment.getAnswerId().equals(blogComment.getUserId())).findFirst();// 这里使用了Optional 只有pcomment!=null 的时候才会执行下面的代码pComment.ifPresent(v -> {comment.setPNickName(v.getNickName());comment.setPIcon(v.getIcon());});// 判断是否点赞isBlogCommentLiked(comment);});rootComment.setChildren(comments);// 判断是否点赞isBlogCommentLiked(rootComment);}return Result.ok(rootComments);}
7.前端实现
因为前端代码很多,只copy关键代码
<html><body><div class="comment-list"><div class="comment-box" style="display: block" v-for="comment in commnetList" :key="comment.id"><div style="display:flex"><div class="comment-icon"><img :src="comment.icon" alt=""></div><div class="comment-info"><div class="comment-user">{{comment.nickName}}</div><div style="display: flex">{{comment.createTime}}<div style="margin-left: 42%;display: flex;"><div @click="addCommnetLike(comment)" style="display: flex"><svg t="1646634642977" class="icon" viewBox="0 0 1024 1024" version="1.1"xmlns="http://www.w3.org/2000/svg" p-id="2187" width="14" height="14"><pathd="M160 944c0 8.8-7.2 16-16 16h-32c-26.5 0-48-21.5-48-48V528c0-26.5 21.5-48 48-48h32c8.8 0 16 7.2 16 16v448zM96 416c-53 0-96 43-96 96v416c0 53 43 96 96 96h96c17.7 0 32-14.3 32-32V448c0-17.7-14.3-32-32-32H96zM505.6 64c16.2 0 26.4 8.7 31 13.9 4.6 5.2 12.1 16.3 10.3 32.4l-23.5 203.4c-4.9 42.2 8.6 84.6 36.8 116.4 28.3 31.7 68.9 49.9 111.4 49.9h271.2c6.6 0 10.8 3.3 13.2 6.1s5 7.5 4 14l-48 303.4c-6.9 43.6-29.1 83.4-62.7 112C815.8 944.2 773 960 728.9 960h-317c-33.1 0-59.9-26.8-59.9-59.9v-455c0-6.1 1.7-12 5-17.1 69.5-109 106.4-234.2 107-364h41.6z m0-64h-44.9C427.2 0 400 27.2 400 60.7c0 127.1-39.1 251.2-112 355.3v484.1c0 68.4 55.5 123.9 123.9 123.9h317c122.7 0 227.2-89.3 246.3-210.5l47.9-303.4c7.8-49.4-30.4-94.1-80.4-94.1H671.6c-50.9 0-90.5-44.4-84.6-95l23.5-203.4C617.7 55 568.7 0 505.6 0z"p-id="2188" :fill="comment.isLike ? '#ff6633' : '#82848a'"></path></svg>{{comment.liked}}</div><div style=" display:flex"><el-dropdown trigger="click" size="mini" placement="top" type="mini"><i class="el-icon-more"></i><el-dropdown-menu><el-dropdown-item><div @click="replyCommentForm(comment)">回复</div></el-dropdown-item><el-dropdown-item><div v-if="comment.userId == user.id" @click="deleteComment(comment.id)">删除</div></el-dropdown-item></el-dropdown-menu></el-dropdown></div></div></div><div style="padding: 5px 0; font-size: 14px;display: flex;"><div>{{comment.content}}</div></div></div></div><div v-if="comment.children.length" style="padding-left: 5px;"><div v-for="reply in comment.children" :key="reply.id" style="padding: 5px 10px"><div style="display: flex"><div class="comment-icon"><img :src="reply.icon" alt=""></div><div class="comment-info"><div class="comment-user">{{reply.nickName}} 回复: {{reply.pnickName}}</div><div style="display: flex">{{reply.createTime}}<div style="margin-left: 40%;display: flex;"><div style="display: flex" @click="addCommnetLike(reply)"><svg t="1646634642977" class="icon" viewBox="0 0 1024 1024" version="1.1"xmlns="http://www.w3.org/2000/svg" p-id="2187" width="14" height="14"><pathd="M160 944c0 8.8-7.2 16-16 16h-32c-26.5 0-48-21.5-48-48V528c0-26.5 21.5-48 48-48h32c8.8 0 16 7.2 16 16v448zM96 416c-53 0-96 43-96 96v416c0 53 43 96 96 96h96c17.7 0 32-14.3 32-32V448c0-17.7-14.3-32-32-32H96zM505.6 64c16.2 0 26.4 8.7 31 13.9 4.6 5.2 12.1 16.3 10.3 32.4l-23.5 203.4c-4.9 42.2 8.6 84.6 36.8 116.4 28.3 31.7 68.9 49.9 111.4 49.9h271.2c6.6 0 10.8 3.3 13.2 6.1s5 7.5 4 14l-48 303.4c-6.9 43.6-29.1 83.4-62.7 112C815.8 944.2 773 960 728.9 960h-317c-33.1 0-59.9-26.8-59.9-59.9v-455c0-6.1 1.7-12 5-17.1 69.5-109 106.4-234.2 107-364h41.6z m0-64h-44.9C427.2 0 400 27.2 400 60.7c0 127.1-39.1 251.2-112 355.3v484.1c0 68.4 55.5 123.9 123.9 123.9h317c122.7 0 227.2-89.3 246.3-210.5l47.9-303.4c7.8-49.4-30.4-94.1-80.4-94.1H671.6c-50.9 0-90.5-44.4-84.6-95l23.5-203.4C617.7 55 568.7 0 505.6 0z"p-id="2188" :fill="reply.isLike ? '#ff6633' : '#82848a'"></path></svg>{{reply.liked}}</div><div style="display:flex"><el-dropdown trigger="click" size="mini" placement="top" type="mini"><i class="el-icon-more"></i><el-dropdown-menu><el-dropdown-item><div @click="replyCommentForm(reply)">回复</div></el-dropdown-item><el-dropdown-item><div v-if="reply.userId == user.id" @click="deleteComment(reply.id)">删除</div></el-dropdown-item></el-dropdown-menu></el-dropdown></div></div></div><div style="padding: 5px 0; font-size: 14px;display: flex;"><div>{{reply.content}}</div></div></div></div></div></div></div></div><script>let each = function (ary, callback) {for (let i = 0, l = ary.length; i < l; i++) {if (callback(ary[i], i) === false) break}}const app = new Vue({el: "#app",data: {util,showPopover: false,actions: [{ text: '回复', icon: '' }, { text: '删除', icon: '' }],commentsTotal: '',// 评论总数checkCommentInputVisible: false,// 判断是否点击回复commnetList: {},// 评论回复列表placeholderText: '发条友善评论吧~~',commentForm: {content: '',userId: '',blogId: '',parentId: 0,answerId: 0,}, // 评论表单blog: {},shop: {},likes: [],user: {}, // 登录用户methods: {replyCommentForm(comment) {this.placeholderText = "回复 " + comment.nickNamethis.checkCommentInputVisible = true;if (comment.parentId == 0) {this.commentForm.parentId = comment.id;} else {this.commentForm.parentId = comment.parentId;}this.commentForm.answerId = comment.userId;},submitCommentForm() {this.commentForm.userId = this.user.id;this.commentForm.blogId = this.blog.id;axios.post("/blog-comments/saveBlogComment", this.commentForm).then(res => {this.loadComments(this.blog.id);this.checkCommentInputVisible = false;}).catch(err => this.$message.error(err))},loadComments(id) {axios.get("/blog-comments/showBlogComments/" + id).then(res => {this.commnetList = res.data}).catch(err => this.$message.err(error))},}</script></body></html>
8.最终成果
点赞、评论、回复、删除
如果需要源码,可以评论区留言,我天天都会看的哦!感谢!