mongoTemplate实现带分页查询

所有数据存储在mongodb中，在mongodb中进行分页，需要自己处理分页条件，使用skip和limit进行查询当前页面的数据。

注意：
mongo是通过正则表达式的形式增加模糊过滤
mongodb对数据类型敏感

package com.jesse.service.impl.metadata;

import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang.StringUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.mongodb.core.MongoTemplate;
import org.springframework.data.mongodb.core.aggregation.Aggregation;
import org.springframework.data.mongodb.core.aggregation.AggregationOperation;
import org.springframework.data.mongodb.core.aggregation.AggregationResults;
import org.springframework.data.mongodb.core.query.Criteria;
import org.springframework.data.mongodb.core.query.Query;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import java.util.*;
import java.util.regex.Pattern;

/**
 * 业务实现
 * @author jesse
 * @date 2021-01-12 10:23:32
 */
@Slf4j
@Service
@Transactional(rollbackFor = Exception.class)
public class MetadataCheckHistoryServiceImpl extends BaseServiceImpl<MetadataCheckHistory,Integer, MetadataCheckHistoryMapper> implements MetadataCheckHistoryService {

    @Autowired
    private  MongoTemplate mongoTemplate;
    
    /**
     * 带分页的查询
     * @param page
     * @param checkTable
     * @return
     */
    @Override
    public Page<MetadataCheckTable> selectMetadataCheckTable(Page<MetadataCheckTable> page, MetadataCheckTable checkTable) {
        long currentPage = page.getCurrentPage();
        long pageSize = page.getPageSize();
        long skip = (currentPage-1)*pageSize;
        Criteria criteria = Criteria.where(MongoDbCollectionEnum.TASK_ID.getValue()).is(checkTable.getTaskId()+"")
                .and(MongoDbCollectionEnum.CHECK_CONFIG_ID.getValue()).is(checkTable.getCheckConfigId()+"");
        //如果表名不为空，增加表名模糊过滤，mongo是通过正则表达式的形式
        if (StringUtils.isNotBlank(checkTable.getTableName())){
            Pattern pattern = Pattern.compile(".*"+checkTable.getTableName()+".*", Pattern.CASE_INSENSITIVE);
            criteria.and("tableName").regex(pattern);
        }
        //增加条件，属性值>0
        if (StringUtils.isNotBlank(checkTable.getCheckAttrName())){
            criteria.and("metrics.tableCheck.attrCheck."+checkTable.getCheckAttrName()).gt(0);
        }
        Query query = new Query(criteria);
        //获取总数量
        long total = mongoTemplate.count(query, MetadataCheckTable.class, MetaDataCheckHistoryConstants.METADATA_CHECK_METRIC);
        //获取总页数
        long pages = (long)Math.ceil(total/pageSize) ;
        //mongo分页通过skip和limit
        query.skip(skip).limit((int)pageSize);
        //查询当前页的数据。
        List<MetadataCheckTable> list = mongoTemplate.find(query, MetadataCheckTable.class,MetaDataCheckHistoryConstants.METADATA_CHECK_METRIC);
        //处理结果集，将相应数据封装到实体
        list.forEach(metadataCheckTable -> {
            LinkedHashMap<String, String> attrCheck = metadataCheckTable.getTableResult().get("attrCheck");
            if (attrCheck!=null &&!attrCheck.isEmpty()){
                //attrCheck是map，可以直接获取values。
                String values = attrCheck.values().toString();
                //去掉两边的[]
                String attrName = StringUtils.strip(values,"[]");
                metadataCheckTable.setAttrCheck(attrName);
            }
        });
        //将结果封装到page中。
        Page<MetadataCheckTable> pageList = new Page<>();
        pageList.setTotal(total);
        pageList.setPages(pages);
        pageList.setCurrentPage(currentPage);
        pageList.setPageSize(pageSize);
        pageList.setRecords(list);

        return pageList;
    }

}