Java中如何使用Mongo的lookup关键字

Java中如何使用Mongo的lookup关键字

1. pom依赖

<dependency>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-data-mongodb</artifactId>
  <version>2.2.1.RELEASE</version>
</dependency>

2. 实体

@Data
@Document("task_ver")
public class TaskVer {

    @Field("taskid")
    private Integer taskId;

    @Field("ver")
    private Integer ver;

    @Field("flowid")
    private Integer flowId;

    @Field("flowver")
    private Integer flowVer;

    @Field("verseq")
    private Integer verSeq;

    @Field("versource")
    private Integer verSource;

    @Field("taskcn")
    private String taskCn;

    @Field("tasken")
    private String taskEn;
}

@Data
@Document("task_alg_ver")
public class TaskAlgVer {

    @Field("taskid")
    private Integer taskId;

    @Field("ver")
    private Integer ver;

    @Field("info")
    private String info;

    @Field("para")
    private String para;
}

@Data
public class TaskVo extends TaskOrchVer {
    //注意这里lookup直接使用TaskAlgVer实体会映射失败
    @Field("taskAlgVer")
    private List<JSONObject> taskAlgVer;
}

3. 代码实现

    Criteria criteria = new Criteria();
    //过滤空间分析类型8
    criteria.and("tasktype").is(8);
    criteria.and("status").in(Arrays.asList(2, 21));
    if (StringUtils.hasText(analysisListVo.getName())) {
        criteria.and("taskcn").regex("^.*" + analysisListVo.getName() + ".*$");
    }
    MatchOperation matchOperation = Aggregation.match(criteria);
    LookupOperation algLook = LookupOperation.newLookup().from("task_ver_alg").localField("taskid").foreignField("taskid").as("taskAlgVer");
    //        UnwindOperation algUnwind = Aggregation.unwind("taskVerAlgs", true);
    //排序
    SortOperation sort = null;
    if (StringUtils.hasText(analysisListVo.getSortField())) {
        sort = Aggregation.sort(Sort.by(new Sort.Order(analysisListVo.getSortType() == -1 ? Sort.Direction.DESC : Sort.Direction.ASC, analysisListVo.getSortField().toLowerCase())));
    } else {
        sort = Aggregation.sort(Sort.by(new Sort.Order(analysisListVo.getSortType() == -1 ? Sort.Direction.DESC : Sort.Direction.ASC, "inserttime")));
    }
    long pageNumber = analysisListVo.getCurPage();
    long pageSize = analysisListVo.getPageSize();
    ResultWrapper<TaskVo> page = new ResultWrapper<>();
    page.setCurPage(pageNumber);
    page.setPageSize(pageSize);
    SkipOperation skip = Aggregation.skip((pageNumber - 1) * pageSize);
    LimitOperation limit = Aggregation.limit(pageSize);
    AggregationOptions aggregationOptions = AggregationOptions.builder().allowDiskUse(true).build();
    Aggregation aggregation = Aggregation.newAggregation(matchOperation, algLook, sort, skip, limit).withOptions(aggregationOptions);
    Aggregation countAggregation = Aggregation.newAggregation(matchOperation, algLook, sort).withOptions(aggregationOptions);

    long count = primaryMongoTemplate.aggregate(countAggregation, "task_ver", TaskVo.class).getMappedResults().size();
    page.setTotal(count);
    long totalPage = count / pageSize;
    page.setTotalPage(count % pageSize == 0 ? totalPage : (totalPage + 1));
    List<TaskVo> tasks = primaryMongoTemplate.aggregate(aggregation, "task_ver", TaskVo.class).getMappedResults();
    page.setDatasList(tasks);