如果jpa不支持联合，您可以尝试两种选择。
创建本机查询并从entitymanager执行，结果是POJO列表。
像这样抛出3个查询：
共享职位：

private Integer id;
private Integer projectId;
private Date startDate; 
private Date endDate

public SharesPojo(Integer id, Integer projectId, Date startDate, Date endDate);

道：

CriteriaBuilder cb = em.getCriteriaBuilder();

CriteriaQuery<SharesPojo> csQuery = cb.createQuery(SharesPojo.class);
Root<ConstructionShares> csRoot = csQuery.from(ConstructionShares.class);
csQuery.multiselect(
    csRoot.get(ConstructionShares_.id)
    csRoot.get(ConstructionShares_.projectId)
    csRoot.get(ConstructionShares_.startDate)
    csRoot.get(ConstructionShares_.endDate)
);

CriteriaQuery<SharesPojo> ipsQuery = cb.createQuery(SharesPojo.class);
Root<InterventionPrShares> ipsRoot = ipsQuery.from(InterventionPrShares.class);
ipsQuery.multiselect(
    ipsRoot.get(InterventionPrShares_.id)
    ipsRoot.get(InterventionPrShares_.projectId)
    ipsRoot.get(InterventionPrShares_.startDate)
    ipsRoot.get(InterventionPrShares_.endDate)
);

CriteriaQuery<SharesPojo> isQuery = cb.createQuery(SharesPojo.class);
Root<InterventionShares> isRoot = isQuery.from(InterventionShares.class);
isQuery.multiselect(
    isRoot.get(InterventionShares_.id)
    isRoot.get(InterventionShares_.projectId)
    isRoot.get(InterventionShares_.startDate)
    isRoot.get(InterventionShares_.endDate)
);

List<SharesPojo> unionList = new ArrayList<>();
unionList.addAll(em.createQuery(csQuery).getResultList());
unionList.addAll(em.createQuery(ipsQuery).getResultList());
unionList.addAll(em.createQuery(isQuery).getResultList());