一、导入依赖

 <dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-data-mongodb</artifactId></dependency>

二、编写配置文件连接Mongodb

我的认证数据库是admin，你们可能不一样

spring:data:mongodb:host: 192.168.110.223port: 27017username: root#password: 123456# 将纯数字密码加字符串password: smartdatabase: articledbauthentication-database: admin

三、编写实体

@Data
//复合索引
@CompoundIndex( def = "{'userid': 1, 'nickname': -1}")
@Document("comment")
public class Comment implements Serializable {@Idprivate String id;//吐槽内容private String content;//发布日期private Date publishtime;@Indexedprivate String userid;//昵称private String nickname;//评论的日期时间private LocalDateTime createdatetime;//点赞数private Integer likenum;//回复数private Integer replynum;//状态private String state;//上级IDprivate String parentid;private String articleid;

四、操作数据

        可以是spring的模板方法进行crud操作，也可以自己设置Repository层进行操作，方法名和JPA有点相似。Repository默认的方法比价少，需要自己的写方法，用模板方法就要多一些

@Repository
public interface CommentRepository  extends MongoRepository<Comment,String> {Page<Comment> findByParentid(String parentid, PageRequest of);}

package net.royal.student.service;import net.royal.student.dao.CommentRepository;
import net.royal.student.entity.Comment;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.PageRequest;
import org.springframework.data.mongodb.core.MongoTemplate;
import org.springframework.data.mongodb.core.query.Criteria;
import org.springframework.data.mongodb.core.query.Query;
import org.springframework.data.mongodb.core.query.Update;
import org.springframework.stereotype.Service;import java.util.List;/*** @author Royal*/
@Service
public class CommentService {@Autowiredprivate CommentRepository commentRepository;//注入MongoTemplate@Autowiredprivate MongoTemplate mongoTemplate;/*** 保存一个评论*/public void saveComment(Comment comment) {commentRepository.save(comment);}/*更新一个评论*/public void updateComment(Comment comment) {commentRepository.save(comment);}/*** 根据id删除评论*/public void deleteCommentById(String id) {commentRepository.deleteById(id);}/*** 查询所有评论** @return*/public List<Comment> findCommentList() {
//调用daoreturn commentRepository.findAll();}/*** 根据id查询评论** @param id* @return*/public Comment findCommentById(String id) {
//调用daoreturn commentRepository.findById(id).get();}/*** 根据父id查询分页列表* @param parentid* @param page* @param size* @return*/public Page<Comment> findCommentListPageParentId(String parentid, int page ,int size){return commentRepository.findByParentid(parentid, PageRequest.of(page-1,size));}/*** 点赞-效率低*/public void updateCommentThumbupToIncrementingOld(String id) {Comment comment = commentRepository.findById(id).get();comment.setLikenum(comment.getLikenum()+1);commentRepository.save(comment);}/*** 点赞数+1*/public void updateCommentLikenum(String id){//查询对象Query query = Query.query(Criteria.where("_id").is(id));//更新对象Update update = new Update();update.inc("likenum");mongoTemplate.updateFirst(query, update, "comment");}
}

测试我这里就不演示了，都比较简单。