Question

我是Criteria的新手，无法理解下一件事。

我的实体彼此之间具有连通性

用户：

 //...fields...

 @OneToOne(fetch = FetchType.LAZY, mappedBy = "user")
 private Document document;

文档：

//...fields...

@OneToOne(fetch = FetchType.LAZY)
@PrimaryKeyJoinColumn
private User user;

@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "doc_type_id", nullable = false)
private DocType docType;

@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "citizenship_id", nullable = false)
private Country country;

文档类型：

//...fields...

@Column(nullable = false, length = 5)
private String code;

国家/地区：

//...fields...

@Column(nullable = false, length = 5)
private String code;

我需要使用包含docCode（DocType.code）和citizenshipCode（Country.code）的文档来查找用户。

道：

    //private final EntityManager em;
    public List<User> filterUser(UserView userView) {
    List<User> userList;
    List<Document> documentList;
    Long officeId = userView.officeId;
    String docCode = userView.docCode;
    String citizenshipCode = userView.citizenshipCode;

    CriteriaBuilder criteriaBuilder = em.getCriteriaBuilder();
    CriteriaQuery<User> userQuery = criteriaBuilder.createQuery(User.class);
    Root<User> userRoot = userQuery.from(User.class);
    userQuery.select(userRoot);
    userQuery.where(criteriaBuilder.equal(userRoot.get("office"), officeId));

    //find id of DocType
    Long docTypeId = null;
    if (docCode != null) {
        CriteriaQuery<DocType> docTypeQuery = criteriaBuilder.createQuery(DocType.class);
        Root<DocType> docTypeRoot = docTypeQuery.from(DocType.class);
        docTypeQuery.select(docTypeRoot);
        docTypeQuery.where(criteriaBuilder.equal(docTypeRoot.get("code"), docCode));
        docTypeId = em.createQuery(docTypeQuery).getSingleResult().getId();
    }

    //find id of Country
    Long countryId = null;
    if (citizenshipCode != null) {
        CriteriaQuery<Country> countryQuery = criteriaBuilder.createQuery(Country.class);
        Root<Country> countryRoot = countryQuery.from(Country.class);
        countryQuery.select(countryRoot);
        countryQuery.where(criteriaBuilder.equal(countryRoot.get("code"), citizenshipCode));
        countryId = em.createQuery(countryQuery).getSingleResult().getId();
    }

    if (docTypeId != null || countryId != null) {
        CriteriaQuery<Document> documentQuery = criteriaBuilder.createQuery(Document.class);
        Root<Document> documentRoot = documentQuery.from(Document.class);
        documentQuery.select(documentRoot);
        if (docTypeId != null) {
            //filter for Document which contains docTypeId
            documentQuery.where(criteriaBuilder.equal(documentRoot.get("docType"), docTypeId));
        }
        if (countryId != null) {
            //filter for which contains countryId 
            documentQuery.where(criteriaBuilder.equal(documentRoot.get("country"), countryId));
        }
        documentList = em.createQuery(documentQuery).getResultList();
        List<Integer> idDocuments = new ArrayList<>();
        //find all of required documents     

        documentList.stream().forEach((d) -> idDocuments.add(Math.toIntExact(d.getId())));
        userQuery.where(userRoot.get("document").in(idDocuments));
    }

    userList = em.createQuery(userQuery).getResultList();
    return userList;
}

我对这些行感兴趣

userQuery.where(criteriaBuilder.equal(userRoot.get("office"), officeId));

和

userQuery.where(userRoot.get("document").in(idDocuments));

为什么第一行的过滤器不执行？

我知道有嵌套的子查询，但是我无法正确处理。

Answer 1

我不知道您想使用“ Office”做什么，但是您不应该将不属于问题的内容发布到工作中。 $ cat file{1..4}.txt text1; text1; text1; text2; text2; text2; text3; text3; text3; text4; text4; text4;导致您遇到问题，导致@PrimaryKeyJoinColumn被排除在user_id之外。

Document

并使用它：

@Entity
public class User {
    @Id @GeneratedValue private int id;

     @OneToOne(fetch = FetchType.LAZY, mappedBy = "user")
     private Document document;

@Entity
public class Document {
    @Id @GeneratedValue private int id;

    @OneToOne(fetch = FetchType.LAZY)
    private User user;

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "doc_type_id", nullable = false)
    private DocType docType;

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "citizenship_id", nullable = false)
    private Country country;


@Entity
public class DocType {
    @Id @GeneratedValue private int id;

    @Column(nullable = false, length = 5)
    private String code;

@Entity
public class Country {
    @Id @GeneratedValue private int id;

    @Column(nullable = false, length = 5)
    private String code;

条件API查询失败

1 个答案: