使用Java泛型的Hibernate映射异常
我使用hibernate和泛型来实现一些特性。这里我有两个实体Country和CountryTrans。CountryTrans代表国家的不同翻译(不同名称)。我在这个项目中使用SpringBoot 我有一个包含Id的顶级类使用Java泛型的Hibernate映射异常,java,spring,hibernate,generics,spring-boot,Java,Spring,Hibernate,Generics,Spring Boot,我使用hibernate和泛型来实现一些特性。这里我有两个实体Country和CountryTrans。CountryTrans代表国家的不同翻译(不同名称)。我在这个项目中使用SpringBoot 我有一个包含Id的顶级类 @MappedSuperclass public abstract class AbstractEntity { private Long id; @Id @GeneratedValue(strategy = GenerationType.AUT
@MappedSuperclass
public abstract class AbstractEntity {
private Long id;
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
}
然后是包含翻译类型的多语言对象泛型类
@MappedSuperclass
public abstract class MultiLigualObject<TYPE extends TranslationObject>
extends AbstractEntity {
protected List<TYPE> transInfo = new ArrayList<>();
public abstract List<TYPE> getTransInfo();
public void setTransInfo(List<TYPE> transInfo) {
this.transInfo = transInfo;
}
}
@MappedSuperclass
public abstract class TranslationObject extends AbstractEntity {
private String langCode;
@Column(name = "lang_code")
public String getLangCode() {
return langCode;
}
public void setLangCode(String langCode) {
this.langCode = langCode;
}
}
最后是乡村班
@Entity
@Table(name = "country")
public class Country extends MultiLigualObject<CountryTrans> {
private String countryCode;
private String alternateCode;
@Column(name = "country_code", nullable = false, length = 2)
public String getCountryCode() {
return this.countryCode;
}
public void setCountryCode(String countryCode) {
this.countryCode = countryCode;
}
@Column(name = "alternate_code", length = 3)
public String getAlternateCode() {
return this.alternateCode;
}
public void setAlternateCode(String alternateCode) {
this.alternateCode = alternateCode;
}
@OneToMany(fetch = FetchType.EAGER, mappedBy = "country")
@Override
public List<CountryTrans> getTransInfo() {
return this.transInfo;
}
}
为了测试这一点,我编写了一个简单的测试用例
@Test
public void testCountry() throws Exception {
Country country = countryRepository.findByCountryCode("AD");
}
当我运行这个测试用例时,它给出了以下异常
Caused by: javax.persistence.PersistenceException: [PersistenceUnit: default] Unable to build Hibernate SessionFactory
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.persistenceException(EntityManagerFactoryBuilderImpl.java:1249)
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.access$600(EntityManagerFactoryBuilderImpl.java:120)
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl$4.perform(EntityManagerFactoryBuilderImpl.java:860)
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl$4.perform(EntityManagerFactoryBuilderImpl.java:850)
at org.hibernate.boot.registry.classloading.internal.ClassLoaderServiceImpl.withTccl(ClassLoaderServiceImpl.java:425)
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:849)
at org.springframework.orm.jpa.vendor.SpringHibernateJpaPersistenceProvider.createContainerEntityManagerFactory(SpringHibernateJpaPersistenceProvider.java:60)
at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:343)
at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:318)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1637)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1574)
... 43 more
Caused by: org.hibernate.MappingException: Could not determine type for: java.util.List, at table: country, for columns: [org.hibernate.mapping.Column(trans_info)]
at org.hibernate.mapping.SimpleValue.getType(SimpleValue.java:349)
at org.hibernate.mapping.SimpleValue.isValid(SimpleValue.java:322)
at org.hibernate.mapping.Property.isValid(Property.java:241)
at org.hibernate.mapping.PersistentClass.validate(PersistentClass.java:496)
at org.hibernate.mapping.RootClass.validate(RootClass.java:270)
at org.hibernate.cfg.Configuration.validate(Configuration.java:1360)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1851)
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl$4.perform(EntityManagerFactoryBuilderImpl.java:857)
... 51 more
一些基本的搜索结果表明,这是字段级访问与属性访问之间的问题。但在这里,我在属性级访问中实现了这一点。但不知道为什么它会失败。有什么想法吗
更新
添加CountryRepository
@Repository
public interface CountryRepository extends JpaRepository<Country, Long> {
Country findByCountryCode(String countryCode);
}
Hibernate(或JPA)将使用类的所有属性,除非您特别用@Transient标记它们。它试图找出dbtransInfo
中映射到的列。默认情况下,在表中查找与参数同名的列(transInfo),但无法找到该列。您可以通过告诉它忽略该参数来修复此问题
例如:
@Transient
private List<CountryTrans> transInfo;
@Transient
私有列表transInfo;
您的国家/地区表中有一列名为trans\u info?我相信它正试图将其映射到您的国家实体类,但无法找出它的位置。。。这似乎正确吗?@DavidR no。我在国家表中没有任何名为trans_info的列。请检查更新的答案。我添加了脚本。
CREATE TABLE country (
id bigint(20) NOT NULL AUTO_INCREMENT,
alternate_code varchar(3) DEFAULT NULL,
country_code varchar(2) NOT NULL,
PRIMARY KEY (id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_bin;
CREATE TABLE country_trans (
id bigint(20) NOT NULL AUTO_INCREMENT,
lang_code varchar(255) DEFAULT NULL,
country_id bigint(20) DEFAULT NULL,
name varchar(255) DEFAULT NULL,
PRIMARY KEY (id),
CONSTRAINT FK_COUNTRY_TRAN_ID FOREIGN KEY (country_id) REFERENCES country (id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_bin;
@Transient
private List<CountryTrans> transInfo;