在Hibernate JPA中使用Spring Boot
我在访问@Entity的DAO时遇到问题，该实体有一个组合键，其中一列是外键。它给了我org.hibernate.PropertyAccessException: Could not set field value [...] by reflection当我尝试使用DAO执行findOne（）时。
所以我有两个MySQL关系，all_contacts和contact_phones，按顺序表示如下：contact_phones有一个复合主键，由contactid+number组成，其中，contactId也是all_contacts中相同值的外键。我已经用适当的@OneToMany和@ManyToOne注释建立了关系
所有联系人的实体：
@Entity
@Table(name = "all_contacts")
public class Contact {
@Column(name="userid", columnDefinition ="bigint(13)")
private BigInteger userId;
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
@Column(name="contactid", columnDefinition ="bigint(13)")
private BigInteger contactId;
@OneToMany(mappedBy = "contact", cascade = CascadeType.ALL)
@ElementCollection(targetClass=ContactPhones.class)
private Set<ContactPhones> phones = new HashSet<ContactPhones>(0);
// the rest of the fields, including getters and setters
}
联系电话实体：
@Entity
@Table( name ="contact_phones")
@IdClass(ContactPhonesKey.class)
public class ContactPhones {
@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name="contactid", nullable = false)
@Id
private Contact contact;
@Column(name="phone_type", columnDefinition = "")
private String phoneType;
@Id
@Column(columnDefinition ="bigint(13)")
private BigInteger number;
// getters and setters
}
而且，由于contact_phones类的主键是composite（因此是
@IdClass(ContactPhonesKey.class)），我被迫创建一个key类来指导它：ContactPhonesKey类：
public class ContactPhonesKey implements Serializable {
private Contact contact;
private String number;
public ContactPhonesKey() {}
public ContactPhonesKey(Contact contact, String number) {
this.contact = contact;
this.number = number;
}
// getters and setters
}
但是，每当我试图通过DAO访问某个东西时（当我通过@Autowired创建了它的一个实例时），我就为contact_phones类创建了：
public interface ContactPhonesRepository extends CrudRepository<ContactPhones, BigInteger> {
List<ContactPhones> findByNumberContaining(String number);
@Query(value ="SELECT * FROM contact_phones cp WHERE cp.contactid= :contactId",
nativeQuery=true)
List<ContactPhones> findAllPhonesByContactId(@Param("contactId")BigInteger contactId);
}
由于反射，无法设置ContactPhonesKey类，我收到一个错误。这是我得到的全部错误：
Could not set field value [111456666] value by reflection : [class app.models.relationentities.ContactPhonesKey.number] setter of app.models.relationentities.ContactPhonesKey.number; nested exception is org.hibernate.PropertyAccessException: Could not set field value [111456666] value by reflection : [class app.models.relationentities.ContactPhonesKey.number] setter of app.models.relationentities.ContactPhonesKey.number
最佳答案
您的实体number和ID类ContactPhones之间的字段ContactPhonesKey上存在类型不匹配。在实体上，它声明为BigInteger，而在ID类上，它声明为String。