Question

当我尝试使用复合键时保存实体时出现异常。这是我尝试保存的例外，模型和存储库。有人可以帮忙吗？

org.springframework.beans.TypeMismatchException：无法转换 'org.CheckType _ $$ _ jvst96c_4'类型的属性值为必需类型 'int'表示属性'checkType';嵌套异常是 java.lang.IllegalArgumentException：无法转换类型的值 'org.CheckType _ $$ _ jvst96c_4'到属性所需的类型'int' 'checkType'：PropertyEditor [org.springframework.beans.propertyeditors.CustomNumberEditor] 返回类型'org.CheckType _ $$ _ jvst96c_4'
的不适当值

@Entity
public class CheckType {
    @Id
    private int id;

    @NotNull
    private String name;

    @OneToMany(mappedBy = "checkType")
    private List<ClientCheck> checks;
    //getters and setters
}

@Entity
public class Offer {
    @Id
    @Column(name = "offerid")
    private Integer offerId;
    //...
    @OneToMany(mappedBy = "offer")
    private List<ClientCheck> clientCheckList;

    //getters and setters
}

@Entity
@IdClass(ClientCheckId.class)
public class ClientCheck {
    @Id
    @ManyToOne
    @JoinColumn(name = "offer_id", referencedColumnName = "offerid")
    private Offer offer;

    @Id
    @ManyToOne
    @JoinColumn(name = "check_type_id", referencedColumnName = "id")
    private CheckType checkType;

    @Id
    private Date timestamp;

    private String result;
    //getters and setters
}

public class ClientCheckId implements Serializable {
    private int offer;
    private int checkType;
    private Date timestamp;

    //getters and setters
    //equals and hashCode
}

public interface ClientCheckRepo extends JpaRepository<ClientCheck, ClientCheckId> {
}

Answer 1

如果另一个实体是复合键的一部分，则必须在ID类中声明该实体，而不是其ID：

public class ClientCheckId implements Serializable {
    private int offer;
    private CheckType checkType;
    private Date timestamp;

    //getters and setters
    //equals and hashCode
}

如果您想了解Hibernate的工作原理，则错误消息非常易读：org.CheckType_$$_jvst96c_4是您的类的丰富版本，Hibernate试图通过反射将checkType字段分配给ClientCheckId字段，由于类型不兼容而失败。

无法使用复合键保存实体

1 个答案: