java - Hibernate 无法确定集合的类型

Question

我收到如下错误:

org.hibernate.MappingException: Could not determine type for: java.util.Collection, at table: customers, for columns: [org.hibernate.mapping.Column(contacts)]

我的代码如下:

@Setter
@MappedSuperclass
@NoArgsConstructor
@EqualsAndHashCode(callSuper = true)
public abstract class PersonEntity<C extends ContactEntity> extends BaseEntity {

    protected String firstName;
    protected String lastName;

    @Column(name = FIRST_NAME_COLUMN, nullable = false)
    public String getFirstName() {
        return firstName;
    }

    @Column(name = LAST_NAME_COLUMN, nullable = false)
    public String getLastName() {
        return lastName;
    }

    public abstract Collection<C> getContacts();
}

人物实体

@Setter
@MappedSuperclass
@NoArgsConstructor
@EqualsAndHashCode(callSuper = true)
public abstract class ContactEntity extends BaseEntity {

    private String contact;

    @Column(name = CONTACT_COLUMN, nullable = false)
    public String getContact() {
        return contact;
    }
}

客户

@Entity
@Setter
@NoArgsConstructor
@EqualsAndHashCode(callSuper = true)
@Table(name = TABLE_NAME)
public class Customer extends PersonEntity<CustomerContact> implements User {

    private Collection<CustomerContact> contacts;

    @Id
    @Override
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = SEQUENCE_NAME)
    @SequenceGenerator(name = SEQUENCE_NAME, sequenceName = SEQUENCE_NAME, allocationSize = 1)
    public Long getId() {
        return this.id;
    }

    @Override
    @OneToMany(targetEntity = CustomerContact.class, mappedBy = "customer", cascade = {CascadeType.PERSIST, CascadeType.MERGE}, orphanRemoval = true)
    public Collection<CustomerContact> getContacts() {
        return contacts;
    }
}

联系实体

@Entity
@Setter
@NoArgsConstructor
@Table(name = TABLE_NAME)
@ToString(exclude = "customer")
public class CustomerContact extends ContactEntity {


    private Customer customer;

    @Id
    @Override
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = SEQUENCE_NAME)
    @SequenceGenerator(name = SEQUENCE_NAME, sequenceName = SEQUENCE_NAME, allocationSize = 1)
    public Long getId(){
        return this.id;
    }

    @ManyToOne
    @JsonIgnore
    @JoinColumn(name = CUSTOMER_COLUMN, nullable = false)
    public cCustomer getCustomer() {
        return customer;
    }
}

客户联系方式

是否可以向具有泛型类型的父类添加抽象方法，然后使用所选类型覆盖它？

Answer 1

那是因为您使用的是@Id注释。您应该将 JPA 注释放在字段本身而不是 getter 上，

@OneToMany(targetEntity = CustomerContact.class, mappedBy = "customer", cascade = {CascadeType.PERSIST, CascadeType.MERGE}, orphanRemoval = true)
private Collection<CustomerContact> contacts;