[英]Many to many org.hibernate.PersistentObjectException: detached entity passed to persist
[英]org.hibernate.PersistentObjectException: detached entity passed to persist: Many to one unidirectional
我正在尝试在 Spring Boot 中使用 hibernate 进行多对一单向映射。 我有以下学生班 - 许多
package jpa.many.to.one.unidirectional.model;
import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
import javax.persistence.Table;
@Entity
@Table(name = "STUDENT")
public class Student {
@Id
@GeneratedValue
@Column(name = "STUDENT_ID")
private long id;
@Column(name = "FIRST_NAME")
private String firstName;
@Column(name = "LAST_NAME")
private String lastName;
@Column(name = "SECTION")
private String section;
@ManyToOne(cascade = CascadeType.ALL)
@JoinColumn(name="UNIVERSITY_ID")
private University university;
public Student() {
}
public Student(String firstName, String lastName, String section, University university) {
this.firstName = firstName;
this.lastName = lastName;
this.section = section;
this.university = university;
}
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public String getSection() {
return section;
}
public void setSection(String section) {
this.section = section;
}
public University getUniversity() {
return university;
}
public void setUniversity(University university) {
this.university = university;
}
@Override
public String toString() {
return "Student [id=" + id + ", firstName=" + firstName + ", lastName="
+ lastName + ", section=" + section + "]";
}
}
大学 - 一个班级
package jpa.many.to.one.unidirectional.model;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Table;
@Entity
@Table(name = "UNIVERSITY")
public class University {
@Id
@GeneratedValue
@Column(name = "UNIVERSITY_ID")
private long id;
@Column(name = "NAME")
private String name;
@Column(name = "COUNTRY")
private String country;
public University() {
}
public University(String name, String country) {
this.name = name;
this.country = country;
}
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getCountry() {
return country;
}
public void setCountry(String country) {
this.country = country;
}
@Override
public String toString() {
return "University [id=" + id + ", name=" + name + ", country=" + country + "]";
}
}
应用程序保存并运行为
package jpa.many.to.one.unidirectional;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ConfigurableApplicationContext;
import jpa.many.to.one.unidirectional.model.Student;
import jpa.many.to.one.unidirectional.model.University;
import jpa.many.to.one.unidirectional.repo.StudentRepo;
import jpa.many.to.one.unidirectional.repo.UniversityRepo;
@SpringBootApplication
public class Application {
public static void main(String[] args) {
// SpringApplication.run(Application.class, args);
ConfigurableApplicationContext configurableApplicationContext = SpringApplication.run(Application.class, args);
UniversityRepo universityRepo = configurableApplicationContext.getBean(UniversityRepo.class);
StudentRepo studentRepo = configurableApplicationContext.getBean(StudentRepo.class);
University university = new University("MG", "India");
Student fstudent = new Student("Deeksha", "Sivakumar", "A", university);
fstudent.setUniversity(university);
studentRepo.save(fstudent);
Student fstudent1 = new Student("Sivakumar", "Nair", "A", university);
fstudent1.setUniversity(university);
studentRepo.save(fstudent1);
}
}
但我得到了引起:org.hibernate.PersistentObjectException:分离实体传递给持久化:jpa.many.to.one.unidirectional.model.University at org.hibernate.event.internal.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:120)在 org.hibernate.event.service.internal.EventListenerGroupImpl.fireEventOnEachListener(EventListenerGroupImpl.java:113) 在 org.hibernate.internal.SessionImpl.firePersist(SessionImpl.java:744) 在 org.hibernate.internal.SessionImpl.persist(SessionImpl) .java:712) 在 org.hibernate.engine.spi.CascadingActions$7.cascade(CascadingActions.java:298) 在 org.hibernate.engine.internal.Cascade.cascadeToOne(Cascade.java:492) 在 org.hibernate.engine .internal.Cascade.cascadeAssociation(Cascade.java:416) at org.hibernate.engine.internal.Cascade.cascadeProperty(Cascade.java:218) at org.hibernate.engine.internal.Cascade.cascade(Cascade.java:151) ) 在 org.hibernate.event.internal.AbstractSaveEventListener.cascadeBeforeSave(AbstractSaveEventListener.java:427) a t org.hibernate.event.internal.AbstractSaveEventListener.performSaveOrReplicate(AbstractSaveEventListener.java:264) 位于 org.hibernate.event.internal.AbstractSaveEventListener.performSave(AbstractSaveEventListener.java:193) 位于 org.hibernate.event.inavesaverate. (AbstractSaveEventListener.java:135) at org.hibernate.event.internal.DefaultPersistEventListener.entityIsTransient(DefaultPersistEventListener.java:185) at org.hibernate.event.internal.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:128) at org.hibernate event.internal.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:55) at org.hibernate.event.service.internal.EventListenerGroupImpl.fireEventOnEachListener(EventListenerGroupImpl.java:102) at org.hibernate.internal.SessionImpl.firePersist(SessionImpl.java: 720) 在 org.hibernate.internal.SessionImpl.persist(SessionImpl.java:706) 在 java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native方法)在 java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) 在 java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) 在 java.base/java .lang.reflect.Method.invoke(Method.java:567) at org.springframework.orm.jpa.SharedEntityManagerCreator$SharedEntityManagerInvocationHandler.invoke(SharedEntityManagerCreator.java:314) at com.sun.proxy.$Proxy55.persist(Unknown Source) ) 在 org.springframework.data.jpa.repository.support.SimpleJpaRepository.save(SimpleJpaRepository.java:554) 在 java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 在 java.base/jdk.internal .reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) 在 java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) 在 java.base/java.lang.reflect.Method.invoke(Method) .java:567) 在 org.springframework.data.repository.core.support.ImplementationInvocati onMetadata.invoke(ImplementationInvocationMetadata.java:72) 在 org.springframework.data.repository.core.support.RepositoryComposition$RepositoryFragments.invoke(RepositoryComposition.java:382) 在 org.springframework.data.repository.core.support.RepositoryComposition。 invoke(RepositoryComposition.java:205) at org.springframework.data.repository.core.support.RepositoryFactorySupport$ImplementationMethodExecutionInterceptor.invoke(RepositoryFactorySupport.java:550) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java) 186) 在 org.springframework.data.repository.core.support.QueryExecutorMethodInterceptor.doInvoke(QueryExecutorMethodInterceptor.java:155) 在 org.springframework.data.repository.core.support.QueryExecutorMethodInterceptor.invoke(QueryExecutorMethodInterceptor.java:130) .springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) 在 org.springframework.data.projection.DefaultMethod InvokingMethodInterceptor.invoke(DefaultMethodInvokingMethodInterceptor.java:80) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspect7) .springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:118) 在 org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) 在 org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.java:118) .java:139) ...还有 13 个
我在多对一注释中尝试了 cascade.merge 和 optional-=false 。 但我得到了上面提到的错误,请帮忙
@ManyToOne(cascade = CascadeType.ALL) 在您的情况下似乎是一个坏主意,因为删除学生会导致删除相关大学。 由于一所大学可以有多个学生,其他学生将成为孤儿
我认为你应该在 University Entity 中使用这种关系,而不是 Student Entity
@OneToMany(cascade = CascadeType.ALL)
@JoinColumn(name="STUDENT_ID")
private List<Student> students;
如果您想使用您的模型,请尝试在将大学设置为学生之前保存大学(因为在您的代码中,您试图两次保存同一所大学,第一次使用 fstudent,第二次使用 fstudent1),在这种情况下,我建议您不使用级联:
University university = universityRepo.save(new University("MG", "India"));
Student fstudent = new Student("Deeksha", "Sivakumar", "A", university);
fstudent.setUniversity(university);
studentRepo.save(fstudent);
Student fstudent1 = new Student("Sivakumar", "Nair", "A", university);
fstudent1.setUniversity(university);
studentRepo.save(fstudent1);
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