使用springboot mongodb工具，删除多余字段。

1、pom文件依赖

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

2、代码实现
topping、toppingTime是需要删除的字段。

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
...
import org.springframework.data.domain.Sort;
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 javax.annotation.Resource;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.regex.Pattern;


    public ResponseBean noTopping(ThreadCommentVo threadCommentVo) {
        String source = threadCommentVo.getSource();
        String commentId = threadCommentVo.getCommentId();
        Query query = new Query(Criteria.where("commentId").is(commentId));
        ThreadCommentEntity threadCommentEntity = (ThreadCommentEntity) mongoUtils.getOneByCondition(query, ThreadCommentEntity.class, getCollection(source));
        System.out.println("threadCommentEntity = " + threadCommentEntity);
        if (threadCommentEntity == null || threadCommentEntity.getTopping() == null || threadCommentEntity.getTopping() != 1) {
            return ResponseBean.builder().code(-1).msg("failed").data("非置顶帖子").build();
        }

        Update update = new Update();
        // 删除topping、toppingTime字段
        update.unset("topping");
        update.unset("toppingTime");
        boolean ret = mongoUtils.update(query, update, ThreadCommentEntity.class, getCollection(source));
        return ResponseBean.builder().code(100).msg("success").data(ret).build();
    }