Java 在OneTONE映射中获取实体会返回错误的结果

我有这个

ResourceForSearch.java

@Entity
@Table(name = "RESOURCES")
public class ResourceForSearch {

    @Id
    @Column(name = "IDRESOURCE")
    private long id;

    private String defaultText;

    @OneToOne
    @JoinColumn(name = "IDRESOURCE", referencedColumnName = "IDRESOURCE")
    private TranslationForSearch translation;

    // getters and setters

}

@Entity
@Table(name = "TRANSLATIONS")
public class TranslationForSearch {

    @Column(name = "IDTRANSLATION")
    private long id;

    @Column(name = "IDLANGUAGE")
    private long languageId;

    private String translation;

    @Id
    private long idResource;

    // getters and setters
}

TranslationForSearch.java

@Entity
@Table(name = "RESOURCES")
public class ResourceForSearch {

    @Id
    @Column(name = "IDRESOURCE")
    private long id;

    private String defaultText;

    @OneToOne
    @JoinColumn(name = "IDRESOURCE", referencedColumnName = "IDRESOURCE")
    private TranslationForSearch translation;

    // getters and setters

}

@Entity
@Table(name = "TRANSLATIONS")
public class TranslationForSearch {

    @Column(name = "IDTRANSLATION")
    private long id;

    @Column(name = "IDLANGUAGE")
    private long languageId;

    private String translation;

    @Id
    private long idResource;

    // getters and setters
}

通常，

资源

与N

翻译

（s）相关，

翻译

由

IDTRANSLATION

标识，但为

TRANSLATIONS.IDLANGUAGE

指定一个值，此关系变为

OneToOne

，因为在某种语言中（由

IDLANGUAGE

标识）每个资源只有一个翻译（资源是我想用不同语言翻译的标签）

因此，仅出于搜索目的，我可以将

@Id

注释放在

TranslationForSearch.idResource

字段上，而不是

TranslationForSearch.Id

字段上

以下是我编写的条件查询：

CriteriaQuery<ResourceForSearch> searchQuery = criteriaBuilder.createQuery(ResourceForSearch.class);
Root<ResourceForSearch> searchRoot = searchQuery.from(ResourceForSearch.class);
searchQuery.select(searchRoot);
Join<ResourceForSearch, TranslationForSearch> translationJoin = resourceRoot.join("translation", JoinType.LEFT);
// Here I filter the JOIN clause by language id, having the OneToOne relationship 
translationJoin.on(criteriaBuilder.equal(translationJoin.get("languageId"), 22)); 
// Here I want to fetch the TRANSLATIONS included in the join
resourceRoot.fetch("translation");
List<ResourceForSearch> resultList = em.createQuery(searchQuery).getResultList();

印刷品

Resource id: 81 Language id 22
Resource id: 85 Language id 30
Resource id: 86 Language id 30
Resource id: 87 Language id 30
Resource id: 88 Language id 30

查询中的fetch似乎不起作用，因为查询返回的实体不符合join子句

编辑1： 这是由Hibernate生成的SQL查询

SELECT resourcefo0_.IDRESOURCE AS IDRESOURCE1_2_,
  resourcefo0_.defaultText     AS defaultText6_2_
FROM WIN_RESOURCES resourcefo0_
LEFT OUTER JOIN WIN_TRANSLATIONS translatio1_
ON resourcefo0_.IDRESOURCE  =translatio1_.idResource
AND (translatio1_.IDLANGUAGE =22)

它返回的行数等于WIN_资源的行数。此外，如果我添加select字段TRANSTALIO1_U1.IDLANGUAGE编辑查询，它将返回22的null值（不是30）

问题出在哪里

---

谢谢

如果这是一对一的关系，那么为什么多个资源被标记为一种语言？说一些不尊重join子句的话意味着您实际上已经查看了生成的SQL。你有，不是吗？@PrasadKharkar:因为对于单个资源和单个语言Id，翻译表中只有一个元组。