Question

我有项目类：

@Entity
public class Project implements Serializable{

private static final long serialVersionUID = 1L;

@Id
@GeneratedValue(strategy=GenerationType.AUTO)
@Column(name="id", unique=true )
private Long id;

@Column(name="name", nullable=false, unique = true)
private String name;

@OneToMany(mappedBy="projectid", fetch = FetchType.EAGER)
private Set<Collaborator> collaborators = new HashSet<>();

public Long getId() {
    return id;
}

public void setId(Long id) {
    this.id = id;
}
}

然后协作者：

@Entity
public class Collaborator implements Serializable{

@Id
@GeneratedValue(strategy = GenerationType.AUTO)
@Column(name = "id", unique = true, nullable = false)
private Long id;

@ManyToOne(cascade = CascadeType.ALL, fetch = FetchType.EAGER)
@JoinColumn(nullable = true)
private Project projectid;

public Long getId() {
    return id;
}

public void setId(Long id) {
    this.id = id;
}
}


public Project getProjectid() {
    return projectid;
}

public void setProjectid(Project projectid) {
    this.projectid = projectid;
}

在我的DAO中，我想执行此查询：

@Query("select c from Collaborator as c where c.projectid = ?1 and  c.showable = true")
List<Collaborator> findAllShowableCollaboratorsByProjectidAndShowableTrue(Long projectId);

但是我收到了这个错误：

引起：org.hibernate.property.access.spi.PropertyAccessException：通过反射持久属性[gestionprojet.java]访问字段[private java.lang.Long gestionprojet.java.entities.beans.Project.id]时出错。 entities.beans.Project＃id]：1 在org.hibernate.property.access.spi.GetterFieldImpl.get（GetterFieldImpl.java:71）在org.hibernate.tuple.entity.AbstractEntityTuplizer.getIdentifier（AbstractEntityTuplizer.java:224）在org.hibernate.persister.entity.AbstractEntityPersister.getIdentifier（AbstractEntityPersister.java:4647）在org.hibernate.persister.entity.AbstractEntityPersister.isTransient（AbstractEntityPersister.java:4358）在org.hibernate.engine.internal.ForeignKeys.isTransient（ForeignKeys.java:226） at org.hibernate.engine.internal.ForeignKeys.getEntityIdentifierIfNotUnsaved（ForeignKeys.java:276） at org.hibernate.type.EntityType.getIdentifier（EntityType.java:462）在org.hibernate.type.ManyToOneType.nullSafeSet（ManyToOneType.java:161）在org.hibernate.param.NamedParameterSpecification.bind（NamedParameterSpecification.java:53）在org.hibernate.loader.hql.QueryLoader.bindParameterValues（QueryLoader.java:628）在org.hibernate.loader.Loader.prepareQueryStatement（Loader.java:1956）在org.hibernate.loader.Loader.executeQueryStatement（Loader.java:1909）在org.hibernate.loader.Loader.executeQueryStatement（Loader.java:1887）在org.hibernate.loader.Loader.doQuery（Loader.java:932）在org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections（Loader.java:349）在org.hibernate.loader.Loader.doList（Loader.java:2615）在org.hibernate.loader.Loader.doList（Loader.java:2598）在org.hibernate.loader.Loader.listIgnoreQueryCache（Loader.java:2430）在org.hibernate.loader.Loader.list（Loader.java:2425）在org.hibernate.loader.hql.QueryLoader.list（QueryLoader.java:502）在org.hibernate.hql.internal.ast.QueryTranslatorImpl.list（QueryTranslatorImpl.java:371）在org.hibernate.engine.query.spi.HQLQueryPlan.performList（HQLQueryPlan.java:216）在org.hibernate.internal.SessionImpl.list（SessionImpl.java:1460）在org.hibernate.query.internal.AbstractProducedQuery.doList（AbstractProducedQuery.java:1426）在org.hibernate.query.internal.AbstractProducedQuery.list（AbstractProducedQuery.java:1398）在org.hibernate.Query.getResultList（Query.java:417）在org.springframework.data.jpa.repository.query.JpaQueryExecution $ CollectionExecution.doExecute（JpaQueryExecution.java:114）在org.springframework.data.jpa.repository.query.JpaQueryExecution.execute（JpaQueryExecution.java:78）在org.springframework.data.jpa.repository.query.AbstractJpaQuery.doExecute（AbstractJpaQuery.java:102）在org.springframework.data.jpa.repository.query.AbstractJpaQuery.execute（AbstractJpaQuery.java:92） at org.springframework.data.repository.core.support.RepositoryFactorySupport $ QueryExecutorMethodInterceptor.doInvoke（RepositoryFactorySupport.java:482） at org.springframework.data.repository.core.support.RepositoryFactorySupport $ QueryExecutorMethodInterceptor.invoke（RepositoryFactorySupport.java:460）在org.springframework.aop.framework.ReflectiveMethodInvocation.proceed（ReflectiveMethodInvocation.java:179）在org.springframework.data.projection.DefaultMethodInvokingMethodInterceptor.invoke（DefaultMethodInvokingMethodInterceptor.java:61）在org.springframework.aop.framework.ReflectiveMethodInvocation.proceed（ReflectiveMethodInvocation.java:179） at org.springframework.transaction.interceptor.TransactionInterceptor $ 1.proceedWithInvocation（TransactionInterceptor.java:99） at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction（TransactionAspectSupport.java:280） at org.springframework.transaction.interceptor.TransactionInterceptor.invoke（TransactionInterceptor.java:96）在org.springframework.aop.framework.ReflectiveMethodInvocation.proceed（ReflectiveMethodInvocation.java:179） at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke（PersistenceExceptionTranslationInterceptor.java:136） ...省略了59个常用帧引起：java.lang.IllegalArgumentException：无法将java.lang.Long字段gestionprojet.java.entities.beans.Project.id设置为java.lang.Long at sun.reflect.UnsafeFieldAccessorImpl.throwSetIllegalArgumentException（Unknown Source） at sun.reflect.UnsafeFieldAccessorImpl.throwSetIllegalArgumentException（Unknown Source） at sun.reflect.UnsafeFieldAccessorImpl.ensureObj（Unknown Source） at sun.reflect.UnsafeObjectFieldAccessorImpl.get（Unknown Source） at java.lang.reflect.Field.get（Unknown Source）在org.hibernate.property.access.spi.GetterFieldImpl.get（GetterFieldImpl.java:67） ...省略了98个常见帧

我的环境：

Hibernate core 5.2.3
mysql-connector-java 5.1.37
弹簧jdbc4.3.2.RELEASE
spring-orm 4.3.2.RELEASE

我试过回滚hibernate t版本4但仍然是同样的问题。

任何帮助都将不胜感激。谢谢你

Answer 1

projectid中的Collaborator是Project个对象，而不是Long个对象。因此，将您的存储库方法更改为：

@Query("select c from Collaborator as c where c.projectid.id = ?1 and  c.showable = true")
List<Collaborator> findAllShowableCollaboratorsByProjectidAndShowableTrue(Long projectId);

建议：

请注意，建议不要使用位置参数绑定，因为无法更改参数的顺序（在您的情况下，它似乎很好，因为只有一个参数）。我建议你改变一下：

@Query("select c from Collaborator as c where c.projectid.id = :pid and  c.showable = true")
List<Collaborator> findAllShowableCollaboratorsByProjectidAndShowableTrue(@Param("pid") Long pid);

将projectid用作类型为Project的字段名称有点令人困惑。将名称更改为project更好看。

Hibernate JPA：无法将字段x设置为x

1 个答案:

建议：