springboot+thymeleaf+jpa博客多级评论展示案例

水深无声 2022-09-11 05:27 231阅读 0赞

效果：  
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###  ###

*   *  实体层
     *  业务层：
     *  控制层：
     *  前端：

## 实体层 ##

省略了get set方法

@Entity
    @Table(name = "t_comment")
    public class Comment { 
    
        @Id
        @GeneratedValue
        private Long id;
        private String nickname;
        private String email;
        private String content;
        private String avatar;
        @Temporal(TemporalType.TIMESTAMP)
        private Date createTime;
    
        @ManyToOne
        private Blog blog;
    
        @OneToMany(mappedBy = "parentComment")
        private List<Comment> replyComments = new ArrayList<>();
    
        @ManyToOne
        private Comment parentComment;
    
        private boolean adminComment;
    }

## 业务层： ##

@Service
    public class CommentServiceImpl implements CommentService { 
    
        @Autowired
        private CommentRepository commentRepository;
    
        @Override
        public List<Comment> listCommentByBlogId(Long blogId) { 
            Sort sort = new Sort("createTime");
            List<Comment> comments = commentRepository.findByBlogIdAndParentCommentNull(blogId,sort);
            return eachComment(comments);
        }
    
        @Transactional
        @Override
        public Comment saveComment(Comment comment) { 
            Long parentCommentId = comment.getParentComment().getId();
            if (parentCommentId != -1) { 
                comment.setParentComment(commentRepository.findOne(parentCommentId));
            } else { 
                comment.setParentComment(null);
            }
            comment.setCreateTime(new Date());
            return commentRepository.save(comment);
        }
    
    
        /** * 循环每个顶级的评论节点 * @param comments * @return */
        private List<Comment> eachComment(List<Comment> comments) { 
            List<Comment> commentsView = new ArrayList<>();
            for (Comment comment : comments) { 
                Comment c = new Comment();
                BeanUtils.copyProperties(comment,c);
                commentsView.add(c);
            }
            //合并评论的各层子代到第一级子代集合中
            combineChildren(commentsView);
            return commentsView;
        }
    
        /** * * @param comments root根节点，blog不为空的对象集合 * @return */
        private void combineChildren(List<Comment> comments) { 
    
            for (Comment comment : comments) { 
                List<Comment> replys1 = comment.getReplyComments();
                for(Comment reply1 : replys1) { 
                    //循环迭代，找出子代，存放在tempReplys中
                    recursively(reply1);
                }
                //修改顶级节点的reply集合为迭代处理后的集合
                comment.setReplyComments(tempReplys);
                //清除临时存放区
                tempReplys = new ArrayList<>();
            }
        }
    
        //存放迭代找出的所有子代的集合
        private List<Comment> tempReplys = new ArrayList<>();
        /** * 递归迭代，剥洋葱 * @param comment 被迭代的对象 * @return */
        private void recursively(Comment comment) { 
            tempReplys.add(comment);//顶节点添加到临时存放集合
            if (comment.getReplyComments().size()>0) { 
                List<Comment> replys = comment.getReplyComments();
                for (Comment reply : replys) { 
                    tempReplys.add(reply);
                    if (reply.getReplyComments().size()>0) { 
                        recursively(reply);
                    }
                }
            }
        }
    }

## 控制层： ##

@Controller
    public class CommentController { 
    
        @Autowired
        private CommentService commentService;
    
        @Autowired
        private BlogService blogService;
    
        @Value("${comment.avatar}")//comment.avatar: /images/avatar.png
        private String avatar;
    
        @GetMapping("/comments/{blogId}")
        public String comments(@PathVariable Long blogId, Model model) { 
            model.addAttribute("comments", commentService.listCommentByBlogId(blogId));
            return "blog :: commentList";
            //<div th:fragment="commentList">
        }
    
    // <h3 class="ui dividing header">评论</h3>
    // <div class="comment" th:each="comment : ${comments}">
    // <a class="avatar">
    // <img src="https://unsplash.it/100/100?image=1005" th:src="@{${comment.avatar}}">
    // </a>
    // <div class="content">
    // <a class="author" >
    // <span th:text="${comment.nickname}">Matt</span>
        @PostMapping("/comments")
        public String post(Comment comment, HttpSession session) { 
            Long blogId = comment.getBlog().getId();
            comment.setBlog(blogService.getBlog(blogId));
            User user = (User) session.getAttribute("user");
            if (user != null) { 
                comment.setAvatar(user.getAvatar());
                comment.setAdminComment(true);
            } else { 
                comment.setAvatar(avatar);
            }
            commentService.saveComment(comment);
            return "redirect:/comments/" + blogId;
        }
    }

## 前端： ##

<div id="comment-container" class="ui teal segment">
              <div th:fragment="commentList">
                <div class="ui threaded comments" style="max-width: 100%;">
                  <h3 class="ui dividing header">评论</h3>
                  <div class="comment" th:each="comment : ${comments}">
                    <a class="avatar">
                      <img src="https://unsplash.it/100/100?image=1005" th:src="@{${comment.avatar}}">
                    </a>
                    <div class="content">
                      <a class="author" >
                        <span th:text="${comment.nickname}">Matt</span>
            <div class="ui mini basic teal left pointing label m-padded-mini" th:if="${comment.adminComment}">博主</div>
                      </a>
                      <div class="metadata">
                        <span class="date" th:text="${#dates.format(comment.createTime,'yyyy-MM-dd HH:mm')}">Today at 5:42PM</span>
                      </div>
                      <div class="text" th:text="${comment.content}">
                        How artistic!
                      </div>
                      <div class="actions">
                        <a class="reply" data-commentid="1" data-commentnickname="Matt" th:attr="data-commentid=${comment.id},data-commentnickname=${comment.nickname}" onclick="reply(this)">回复</a>
                      </div>
                    </div>
                    <div class="comments" th:if="${#arrays.length(comment.replyComments)}>0">
                      <div class="comment" th:each="reply : ${comment.replyComments}">
                        <a class="avatar">
                          <img src="https://unsplash.it/100/100?image=1005" th:src="@{${reply.avatar}}">
                        </a>
                        <div class="content">
                          <a class="author" >
                            <span th:text="${reply.nickname}"></span>
                            <div class="ui mini basic teal left pointing label m-padded-mini" th:if="${reply.adminComment}"></div>
                             <span th:text="|@ ${reply.parentComment.nickname}|" class="m-teal"></span>
                          </a>
                          <div class="metadata">
                            <span class="date" th:text="${#dates.format(reply.createTime,'yyyy-MM-dd HH:mm')}"></span>
                          </div>
                          <div class="text" th:text="${reply.content}">
                            How artistic!
                          </div>
                          <div class="actions">
                            <a class="reply" data-commentid="1" data-commentnickname="Matt" th:attr="data-commentid=${reply.id},data-commentnickname=${reply.nickname}" onclick="reply(this)">回复</a>
                          </div>
                        </div>
                      </div>
                    </div>
                  </div>
    
    
    <div id="comment-form" class="ui form">
              <input type="hidden" name="blog.id" th:value="${blog.id}">
              <input type="hidden" name="parentComment.id" value="-1">
              <div class="field">
                <textarea name="content" placeholder="请输入评论信息..."></textarea>
              </div>
              <div class="fields">
                <div class="field m-mobile-wide m-margin-bottom-small">
                  <div class="ui left icon input">
                    <i class="user icon"></i>
                    <input type="text" name="nickname" placeholder="姓名" th:value="${session.user}!=null ? ${session.user.nickname}">
                  </div>
                </div>
                <div class="field m-mobile-wide m-margin-bottom-small">
                  <div class="ui left icon input">
                    <i class="mail icon"></i>
                    <input type="text" name="email" placeholder="邮箱" th:value="${session.user}!=null ? ${session.user.email}">
                  </div>
                </div>
                <div class="field m-margin-bottom-small m-mobile-wide">
                  <button id="commentpost-btn" type="button" class="ui teal button m-mobile-wide"><i class="edit icon"></i>发布</button>
                </div>
              </div>

javascript部分

//评论表单验证
        $('.ui.form').form({ 
          fields: { 
            title: { 
              identifier: 'content',
              rules: [{ 
                type: 'empty',
                prompt: '请输入评论内容'
              }
              ]
            },
            content: { 
              identifier: 'nickname',
              rules: [{ 
                type: 'empty',
                prompt: '请输入你的大名'
              }]
            },
            type: { 
              identifier: 'email',
              rules: [{ 
                type: 'email',
                prompt: '请填写正确的邮箱地址'
              }]
            }
          }
        });
    
        $(function () { 
          $("#comment-container").load(/*[[@{/comments/{id}(id=${blog.id})}]]*/"comments/6");
        });
    
    
    
        $('#commentpost-btn').click(function () { 
          var boo = $('.ui.form').form('validate form');
          if (boo) { 
            console.log('校验成功');
            postData();
          } else { 
            console.log('校验失败');
          }
    
        });
       function postData() { 
          $("#comment-container").load(/*[[@{/comments}]]*/"",{ 
            "parentComment.id" : $("[name='parentComment.id']").val(),
            "blog.id" : $("[name='blog.id']").val(),
            "nickname": $("[name='nickname']").val(),
            "email"   : $("[name='email']").val(),
            "content" : $("[name='content']").val()
          },function (responseTxt, statusTxt, xhr) { 
    // $(window).scrollTo($('#comment-container'),500);
            clearContent();
          });
        }
    
        function clearContent() { 
          $("[name='content']").val('');
          $("[name='parentComment.id']").val(-1);
          $("[name='content']").attr("placeholder", "请输入评论信息...");
        }
    
    
        function reply(obj) { 
          var commentId = $(obj).data('commentid');
          var commentNickname = $(obj).data('commentnickname');
          $("[name='content']").attr("placeholder", "@"+commentNickname).focus();
          $("[name='parentComment.id']").val(commentId);
          $(window).scrollTo($('#comment-form'),500);
        }

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