Java 8 java stream将Spring数据jpa OneToMany集合获取为null

我得到了空点异常，调试得到了claimDataEntity .getEventDataEntityList（）为空 但实际上这个claimDataEntity在db中有相关的事件数据

我在UT中这样做：

function(ValidateClaimDataEntity claimDataEntity){
   claimDataEntity
            .getEventDataEntityList().parallelStream()....
}

它不记录事件数据

那么，为什么函数claimData get eventList为null

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我发现可能不是流的问题， 实际上，我在迭代器之前进行了一次保存

claimDataEntityRepository.findById(32L).get().getEventDataEntityList().parallelStream().forEach(eventDataEntity -> {
            log.info(eventDataEntity.getValidateEventDataId());
        });

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我得到了eventList的两个null对于

@OneToMany

的默认fetchtype是LAZY（）。因此它不会被提取。让它成为渴望的

public ValidateClaimResponse bc(ValidateClaimRequest claimRequest) {

        //claim
        ValidateClaimDataEntity claimDataEntity = new ValidateClaimDataEntity(claimRequest);
        claimDataEntityRepository.save(claimDataEntity);

        claimRequest.getEventRequestList()
                .forEach(eventRequest -> {
                    ...

                    //event
                    ValidateEventDataEntity eventDataEntity = new ValidateEventDataEntity(eventRequest);
                    eventDataEntity.setValidateClaimDataId(claimDataEntity.getValidateClaimDataId());

                    eventDataEntityRepository.save(eventDataEntity);
                });


    System.out.println(claimDataEntity.getEventDataEntityList() == null ? "null" : claimDataEntity.getEventDataEntityList() );

    ValidateClaimDataEntity claimDataEntity2 = claimDataEntityRepository.findById(claimDataEntity.getValidateClaimDataId()).get();
    System.out.println(claimDataEntity2.getEventDataEntityList() == null ? "null2" : claimDataEntity2.getEventDataEntityList());

@OneToMany（mappedBy=“claimDataEntity”，fetch=FetchType.EAGER）
私有列表eventDataEntityList；

使用fetchType作为默认类型

public ValidateClaimResponse bc(ValidateClaimRequest claimRequest) {

        //claim
        ValidateClaimDataEntity claimDataEntity = new ValidateClaimDataEntity(claimRequest);
        claimDataEntityRepository.save(claimDataEntity);

        claimRequest.getEventRequestList()
                .forEach(eventRequest -> {
                    ...

                    //event
                    ValidateEventDataEntity eventDataEntity = new ValidateEventDataEntity(eventRequest);
                    eventDataEntity.setValidateClaimDataId(claimDataEntity.getValidateClaimDataId());

                    eventDataEntityRepository.save(eventDataEntity);
                });


    System.out.println(claimDataEntity.getEventDataEntityList() == null ? "null" : claimDataEntity.getEventDataEntityList() );

    ValidateClaimDataEntity claimDataEntity2 = claimDataEntityRepository.findById(claimDataEntity.getValidateClaimDataId()).get();
    System.out.println(claimDataEntity2.getEventDataEntityList() == null ? "null2" : claimDataEntity2.getEventDataEntityList());

@OneToMany(mappedBy = "claimDataEntity", fetch = FetchType.EAGER)
private List<ValidateEventDataEntity> eventDataEntityList;