Java 外键没有父错误
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时间：2020-08-16 07:28:18 来源:igfitidea点击:
foreign key no parent error
提问by Thom
This is really why I quit using Hibernate to manage my relationships for me. Too many new gray hairs.
这就是为什么我不再使用 Hibernate 来为我管理人际关系的原因。太多新的白发。
Hibernate 3.6.10
休眠 3.6.10
OK, I have two classes, Schedule and Event. Schedule has many events, but an event has only one schedule.
好的，我有两个课程，Schedule 和 Event。时间表有很多事件，但一个事件只有一个时间表。
Schedule:
日程：
/**
*
*/
package com.heavyweightsoftware.leal.model.schedule;
import java.util.ArrayList;
import java.util.Collection;
import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.NamedQueries;
import javax.persistence.NamedQuery;
import javax.persistence.OneToMany;
import javax.persistence.Table;
import com.heavyweightsoftware.leal.helper.DateHelper;
import com.heavyweightsoftware.leal.model.Pojo;
/**
* A particular collection of events that can be shared
* @author Thom
*/
@Entity
@Table(name = "SCHEDULE")
@NamedQueries( {
@NamedQuery(name = Schedule.COUNT_SCHED_ID, query = "SELECT COUNT(*) " +
"FROM Schedule s " +
"WHERE s.scheduleId = :scheduleId"),
@NamedQuery(name = Schedule.COUNT_SCHED_NAME, query = "SELECT COUNT(*) " +
"FROM ScheduleRole r, Schedule s, SystemUser u " +
"WHERE u.email = :email " +
" AND u.id = r.systemUserId " +
" AND r.scheduleId = s.id " +
" AND s.name = :scheduleName "),
@NamedQuery(name = Schedule.QUERY_EVENTS_BY_USER, query = "SELECT r.roleType, s " +
"FROM Schedule s, ScheduleRole r, SystemUser u " +
"WHERE u.email = :email " +
" AND u.id = r.systemUserId " +
" AND r.scheduleId = s.id " +
" ")
}
)
public class Schedule extends Pojo {
public static final int LENGTH_SCHEDULE_ID = 32;
public static final String COUNT_SCHED_ID = "countScheduleId";
public static final String COUNT_SCHED_NAME = "countScheduleName";
public static final String QUERY_EVENTS_BY_USER = "findEventsByUser";
@Column(name = "ID", nullable=false)
@Id @GeneratedValue(strategy=GenerationType.AUTO)
private Integer id;
@Column(name = "NAME", nullable=false)
private String name;
@Column(name = "SCHEDULE_ID", nullable=false, unique=true, length=LENGTH_SCHEDULE_ID)
private String scheduleId;
@OneToMany(cascade = CascadeType.ALL, fetch=FetchType.EAGER, orphanRemoval=true)
@JoinColumn(name="ID")
private Collection<Event> events;
/**
* Copy all members from one to the other
* @param from the from
* @param to the to
* @param copySubMembers if true, copy sub members like entity
*/
public static void copy(Schedule from, Schedule to, boolean copySubMembers){
to.setId(from.getId());
to.setName(from.getName());
to.setScheduleId(from.getScheduleId());
if(copySubMembers){
to.setEvents(from.getEvents());
}
}
/**
* no-arg constructor
*/
public Schedule() {
}
/**
* copy constructor
*/
public Schedule(Schedule schedule) {
copy(schedule, this, true);
}
/* (non-Javadoc)
* @see com.heavyweightsoftware.leal.model.Pojo#toString()
*/
@Override
public String toString() {
StringBuilder sb = new StringBuilder(super.toString());
sb.append('|');
sb.append(getName());
sb.append('|');
sb.append(getScheduleId());
sb.append('|');
sb.append(getEvents());
return sb.toString();
}
/* (non-Javadoc)
* @see java.lang.Object#hashCode()
*/
@Override
public int hashCode() {
final int prime = 31;
int result = super.hashCode();
result = prime * result + ((id == null) ? 0 : id.hashCode());
result = prime * result + ((name == null) ? 0 : name.hashCode());
result = prime * result
+ ((scheduleId == null) ? 0 : scheduleId.hashCode());
return result;
}
/* (non-Javadoc)
* @see java.lang.Object#equals(java.lang.Object)
*/
@Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (!super.equals(obj))
return false;
if (getClass() != obj.getClass())
return false;
Schedule other = (Schedule) obj;
if (id == null) {
if (other.id != null)
return false;
} else if (!id.equals(other.id))
return false;
if (name == null) {
if (other.name != null)
return false;
} else if (!name.equals(other.name))
return false;
if (scheduleId == null) {
if (other.scheduleId != null)
return false;
} else if (!scheduleId.equals(other.scheduleId))
return false;
return true;
}
/**
* @return the id
*/
public final Integer getId() {
return id;
}
/**
* @param id the id to set
*/
public final void setId(Integer id) {
this.id = id;
}
/**
* @return the name
*/
public final String getName() {
return name;
}
/**
* @param name the name to set
*/
public final void setName(String name) {
this.name = name;
}
/**
* @return
*/
public String getScheduleId() {
return scheduleId == null?scheduleId = DateHelper.getUniqueID():scheduleId;
}
/**
* @param scheduleId
*/
public void setScheduleId(String scheduleId) {
this.scheduleId = scheduleId;
}
/**
* @return the events
*/
public Collection<Event> getEvents() {
return events==null?events = new ArrayList<>():events;
}
/**
* @param events the events to set
*/
public void setEvents(Collection<Event> events) {
this.events = events;
}
}
Event:
事件：
/**
*
*/
package com.heavyweightsoftware.leal.model.schedule;
import java.util.Calendar;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
import javax.persistence.NamedQueries;
import javax.persistence.Table;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;
import com.heavyweightsoftware.leal.model.Pojo;
/**
* A particular event entry in a calendar
* @author Thom
*/
@Entity
@Table(name = "EVENT")
@NamedQueries( {
}
)
public class Event extends Pojo {
/**
* Length of the randomly generated event ID
*/
private static final int LENGTH_EVENT_ID = 32;
@Column(name = "ID", nullable=false)
@Id @GeneratedValue(strategy=GenerationType.AUTO)
private Integer id;
@Column(name = "START_TIME")
@Temporal(TemporalType.TIMESTAMP)
private Calendar start;
@Column(name = "END_TIME")
@Temporal(TemporalType.TIMESTAMP)
private Calendar end;
@Column(name = "EVENT_NAME", nullable=false)
private String eventName;
@Column(name = "EVENT_ID", nullable=false, unique=true, length=LENGTH_EVENT_ID)
private String eventId;
@ManyToOne(fetch=FetchType.EAGER)
@JoinColumn(name="SCHEDULE_ID")
private Schedule schedule;
@Column(name = "LOCATION")
private String location;
/* (non-Javadoc)
* @see java.lang.Object#hashCode()
*/
@Override
public int hashCode() {
final int prime = 31;
int result = super.hashCode();
result = prime * result + ((end == null) ? 0 : end.hashCode());
result = prime * result
+ ((eventName == null) ? 0 : eventName.hashCode());
result = prime * result + ((id == null) ? 0 : id.hashCode());
result = prime * result
+ ((location == null) ? 0 : location.hashCode());
result = prime * result
+ ((schedule == null) ? 0 : schedule.hashCode());
result = prime * result + ((start == null) ? 0 : start.hashCode());
return result;
}
/* (non-Javadoc)
* @see java.lang.Object#equals(java.lang.Object)
*/
@Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (!super.equals(obj))
return false;
if (getClass() != obj.getClass())
return false;
Event other = (Event) obj;
if (end == null) {
if (other.end != null)
return false;
} else if (!end.equals(other.end))
return false;
if (eventName == null) {
if (other.eventName != null)
return false;
} else if (!eventName.equals(other.eventName))
return false;
if (id == null) {
if (other.id != null)
return false;
} else if (!id.equals(other.id))
return false;
if (location == null) {
if (other.location != null)
return false;
} else if (!location.equals(other.location))
return false;
if (schedule == null) {
if (other.schedule != null)
return false;
} else if (!schedule.equals(other.schedule))
return false;
if (start == null) {
if (other.start != null)
return false;
} else if (!start.equals(other.start))
return false;
return true;
}
/* (non-Javadoc)
* @see com.heavyweightsoftware.leal.model.Pojo#toString()
*/
@Override
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append(super.toString());
sb.append('|');
sb.append(getEventName());
sb.append('|');
sb.append(getTimestamp(getStart()));
sb.append('-');
sb.append(getTimestamp(getEnd()));
sb.append("|scheduleId=");
Schedule schedule = getSchedule();
sb.append(schedule==null?"null":schedule.getId());
sb.append('|');
sb.append(getLocation());
sb.append('|');
sb.append(getEventId());
return sb.toString();
}
/**
* @return the id
*/
public final Integer getId() {
return id;
}
/**
* @param id the id to set
*/
public final void setId(Integer id) {
this.id = id;
}
/**
* The start date of the event in UTC
* @return the start
*/
public final Calendar getStart() {
return start;
}
/**
* The start date of the event in UTC
* @param start the start to set
*/
public final void setStart(Calendar start) {
this.start = start;
}
/**
* The end date of the event in UTC
* @return the end
*/
public final Calendar getEnd() {
return end;
}
/**
* The end date of the event in UTC
* @param end the end to set
*/
public final void setEnd(Calendar end) {
this.end = end;
}
/**
* @return the eventId
*/
public String getEventId() {
return eventId;
}
/**
* @param eventId the eventId to set
*/
public void setEventId(String eventId) {
this.eventId = eventId;
}
/**
* @return the eventName
*/
public final String getEventName() {
return eventName;
}
/**
* @param eventName the eventName to set
*/
public final void setEventName(String eventName) {
this.eventName = eventName;
}
/**
* @return the location
*/
public final String getLocation() {
return location;
}
/**
* @param location the location to set
*/
public final void setLocation(String location) {
this.location = location;
}
/**
* @return the schedule
*/
public Schedule getSchedule() {
return schedule;
}
/**
* @param schedule the schedule to set
*/
public void setSchedule(Schedule schedule) {
this.schedule = schedule;
}
}
Now at the point I'm getting the exception, I have created a schedule and then added 4 events to the schedule and am calling update on my schedule DAO to save the events. Here is my current code:
现在，我遇到了异常，我创建了一个计划，然后将 4 个事件添加到计划中，并在我的计划 DAO 上调用更新以保存事件。这是我当前的代码：
public Schedule update(Schedule schedule) {
//first save the events
for(Event event:schedule.getEvents()){
getHibernateTemplate().saveOrUpdate(event); //<-Fails here
}
Schedule schedule2 = getHibernateTemplate().get(Schedule.class, schedule.getId());
Schedule.copy(schedule, schedule2, false);
System.err.println(schedule2.toString());
getHibernateTemplate().saveOrUpdate(schedule2);
return retrieveById(schedule2.getId());
}
All fields on my event are populated except the ID, which is auto generated. Here's the exception:
除了自动生成的 ID 外，我的活动中的所有字段都已填充。这是例外：
org.springframework.dao.DataIntegrityViolationException: could not insert: [com.heavyweightsoftware.leal.model.schedule.Event]; SQL [insert into EVENT (ID, END_TIME, EVENT_ID, EVENT_NAME, LOCATION, SCHEDULE_ID, START_TIME) values (default, ?, ?, ?, ?, ?, ?)]; constraint [FK3F47A7AA91E64F]; nested exception is org.hibernate.exception.ConstraintViolationException: could not insert: [com.heavyweightsoftware.leal.model.schedule.Event]
at org.springframework.orm.hibernate3.SessionFactoryUtils.convertHibernateAccessException(SessionFactoryUtils.java:637)
at org.springframework.orm.hibernate3.HibernateAccessor.convertHibernateAccessException(HibernateAccessor.java:412)
at org.springframework.orm.hibernate3.HibernateTemplate.doExecute(HibernateTemplate.java:411)
at org.springframework.orm.hibernate3.HibernateTemplate.executeWithNativeSession(HibernateTemplate.java:374)
at org.springframework.orm.hibernate3.HibernateTemplate.saveOrUpdate(HibernateTemplate.java:737)
at com.heavyweightsoftware.leal.dao.hibernate.schedule.ScheduleHibernateDAO.update(ScheduleHibernateDAO.java:71)
at com.heavyweightsoftware.leal.dao.hibernate.schedule.ScheduleHibernateDAO.update(ScheduleHibernateDAO.java:1)
at com.heavyweightsoftware.leal.service.calendar.impl.CalendarServiceImpl.update(CalendarServiceImpl.java:168)
at com.heavyweightsoftware.leal.service.calendar.impl.CalendarServiceImplTest.testGetCalendars(CalendarServiceImplTest.java:230)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at org.junit.runners.model.FrameworkMethod.runReflectiveCall(FrameworkMethod.java:44)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:41)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:28)
at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:31)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:76)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
at org.junit.runners.ParentRunner.run(ParentRunner.java:193)
at org.junit.runners.ParentRunner.schedule(ParentRunner.java:52)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191)
at org.junit.runners.ParentRunner.access@OneToMany(cascade = CascadeType.ALL, fetch=FetchType.EAGER, orphanRemoval=true)
@JoinColumn(name="ID")
private Collection<Event> events;
0(ParentRunner.java:42)
at org.junit.runners.ParentRunner.evaluate(ParentRunner.java:184)
at org.junit.runners.ParentRunner.run(ParentRunner.java:236)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)
Caused by: org.hibernate.exception.ConstraintViolationException: could not insert: [com.heavyweightsoftware.leal.model.schedule.Event]
at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:96)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66)
at org.hibernate.id.insert.AbstractReturningDelegate.performInsert(AbstractReturningDelegate.java:63)
at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:2346)
at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:2853)
at org.hibernate.action.EntityIdentityInsertAction.execute(EntityIdentityInsertAction.java:71)
at org.hibernate.engine.ActionQueue.execute(ActionQueue.java:273)
at org.hibernate.event.def.AbstractSaveEventListener.performSaveOrReplicate(AbstractSaveEventListener.java:320)
at org.hibernate.event.def.AbstractSaveEventListener.performSave(AbstractSaveEventListener.java:203)
at org.hibernate.event.def.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:129)
at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.saveWithGeneratedOrRequestedId(DefaultSaveOrUpdateEventListener.java:210)
at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.entityIsTransient(DefaultSaveOrUpdateEventListener.java:195)
at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.performSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:117)
at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.onSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:93)
at org.hibernate.impl.SessionImpl.fireSaveOrUpdate(SessionImpl.java:685)
at org.hibernate.impl.SessionImpl.saveOrUpdate(SessionImpl.java:677)
at org.hibernate.impl.SessionImpl.saveOrUpdate(SessionImpl.java:673)
at org.springframework.orm.hibernate3.HibernateTemplate.doInHibernate(HibernateTemplate.java:740)
at org.springframework.orm.hibernate3.HibernateTemplate.doExecute(HibernateTemplate.java:406)
... 30 more
Caused by: java.sql.SQLException: integrity constraint violation: foreign key no parent; FK3F47A7AA91E64F table: EVENT
at org.hsqldb.jdbc.Util.sqlException(Util.java:215)
at org.hsqldb.jdbc.JDBCPreparedStatement.fetchResult(JDBCPreparedStatement.java:4617)
at org.hsqldb.jdbc.JDBCPreparedStatement.executeUpdate(JDBCPreparedStatement.java:308)
at org.hibernate.id.IdentityGenerator$GetGeneratedKeysDelegate.executeAndExtract(IdentityGenerator.java:93)
at org.hibernate.id.insert.AbstractReturningDelegate.performInsert(AbstractReturningDelegate.java:56)
... 46 more
Caused by: org.hsqldb.HsqlException: integrity constraint violation: foreign key no parent; FK3F47A7AA91E64F table: EVENT
at org.hsqldb.error.Error.error(Error.java:131)
at org.hsqldb.Constraint.getException(Constraint.java:898)
at org.hsqldb.Constraint.checkInsert(Constraint.java:816)
at org.hsqldb.StatementDML.performIntegrityChecks(StatementDML.java:1318)
at org.hsqldb.StatementDML.insertRowSet(StatementDML.java:795)
at org.hsqldb.StatementInsert.getResult(StatementInsert.java:139)
at org.hsqldb.StatementDMQL.execute(StatementDMQL.java:190)
at org.hsqldb.Session.executeCompiledStatement(Session.java:1294)
at org.hsqldb.Session.execute(Session.java:956)
at org.hsqldb.jdbc.JDBCPreparedStatement.fetchResult(JDBCPreparedStatement.java:4609)
... 49 more
Thanks! Heartbroken in Lexington:)
谢谢！在列克星敦伤心:)
采纳答案by Perception
Your problem is that you are trying to perform a join from your Scheduleentity to your Evententity, when there is no foreign key relationship in that direction.
您的问题是，当该方向没有外键关系时，您正在尝试执行从Schedule实体到Event实体的连接。
@OneToMany(cascade = CascadeType.ALL, fetch=FetchType.EAGER, mappedBy = "schedule")
private Collection<Event> events;
With the above code you are instructing your JPA provider to retrieve all events for which the Schedule's idcolumn matches with the primary key from Event. I'm pretty sure this is not what you intended. You should allow Eventto define the mapping and then reference that from Schedule:
使用上面的代码，您将指示您的 JPA 提供程序检索 Schedule 的id列与Event. 我很确定这不是你想要的。您应该允许Event定义映射，然后从Schedule以下位置引用它：
Also, I would recommend using Setsto store your collections, since Hibernate has a known problem when storing multiple associations (bags) in an entity, unless you do.
另外，我建议使用Sets来存储您的集合，因为 Hibernate 在一个实体中存储多个关联（包）时存在一个已知问题，除非您这样做。
