我正在尝试使用额外的列保存具有多对多关系的实体，但我收到了一个错误
乐队.java
package it.entities;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.List;
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.ManyToOne;
import javax.persistence.NamedQuery;
import javax.persistence.OneToMany;
import javax.persistence.Table;
/**
* The persistent class for the band database table.
*
*/
@Entity
@Table(name="BAND")
@NamedQuery(name="Band.findAll", query="SELECT b FROM Band b")
public class Band implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "ID", unique = true, nullable = false)
private int id;
@Column(name="DESCRIZIONE")
private String descrizione;
@Column(name="NOME")
private String nome;
//bi-directional many-to-one association to Audio
@ManyToOne
@JoinColumn(name="AUDIO_ID")
private Audio audio;
//bi-directional many-to-one association to Video
@ManyToOne
@JoinColumn(name="VIDEO_ID")
private Video video;
//bi-directional many-to-one association to Citta
@ManyToOne
@JoinColumn(name="CITTA_ID")
private Citta citta;
@OneToMany(mappedBy="pk.band", fetch = FetchType.LAZY, cascade={CascadeType.ALL})
private List<BandHasMusicista> bandHasMusicista = new ArrayList<BandHasMusicista>();
public Band() {
}
public int getId() {
return this.id;
}
public void setId(int id) {
this.id = id;
}
public String getDescrizione() {
return this.descrizione;
}
public void setDescrizione(String descrizione) {
this.descrizione = descrizione;
}
public String getNome() {
return this.nome;
}
public void setNome(String nome) {
this.nome = nome;
}
public Audio getAudio() {
return this.audio;
}
public void setAudio(Audio audio) {
this.audio = audio;
}
public Video getVideo() {
return this.video;
}
public void setVideo(Video video) {
this.video = video;
}
public Citta getCitta() {
return this.citta;
}
public void setCitta(Citta citta) {
this.citta = citta;
}
// @OneToMany(fetch = FetchType.LAZY, mappedBy = "pk.band")
public List<BandHasMusicista> getBandHasMusicista() {
return bandHasMusicista;
}
public void setBandHasMusicista(List<BandHasMusicista> bandHasMusicista) {
this.bandHasMusicista = bandHasMusicista;
}
}
BandHasMusicista.java
package it.entities;
import java.io.Serializable;
import javax.persistence.AssociationOverride;
import javax.persistence.AssociationOverrides;
import javax.persistence.Column;
import javax.persistence.EmbeddedId;
import javax.persistence.Entity;
import javax.persistence.JoinColumn;
import javax.persistence.NamedQuery;
import javax.persistence.Table;
import javax.persistence.Transient;
/**
* The persistent class for the band_has_musicista database table.
*
*/
@Entity
@Table(name="BAND_HAS_MUSICISTA")
@AssociationOverrides({
@AssociationOverride(name = "pk.musicista", joinColumns = @JoinColumn(name = "MUSICISTA_ID")),
@AssociationOverride(name = "pk.band", joinColumns = @JoinColumn(name = "BAND_ID"))})
@NamedQuery(name="BandHasMusicista.findAll", query="SELECT b FROM BandHasMusicista b")
public class BandHasMusicista implements Serializable {
private static final long serialVersionUID = 1L;
private BandHasMusicistaPK pk = new BandHasMusicistaPK();
private Band band;
private Musicista musicista;
private boolean bandAccept;
private boolean musicistaAccept;
public BandHasMusicista() {
}
@EmbeddedId
public BandHasMusicistaPK getPk() {
return pk;
}
public void setPk(BandHasMusicistaPK pk) {
this.pk = pk;
}
@Column(name="BAND_ACCEPT", nullable=false)
public boolean getBandAccept() {
return this.bandAccept;
}
public void setBandAccept(boolean bandAccept) {
this.bandAccept = bandAccept;
}
@Column(name="MUSICISTA_ACCEPT", nullable=false)
public boolean getMusicistaAccept() {
return this.musicistaAccept;
}
public void setMusicistaAccept(boolean musicistaAccept) {
this.musicistaAccept = musicistaAccept;
}
@Transient
// @JoinColumn(name="BAND_ID")
public Band getBand() {
return this.band;
}
public void setBand(Band band) {
this.band = band;
}
@Transient
// @JoinColumn(name="MUSICISTA_ID")
public Musicista getMusicista() {
return this.musicista;
}
public void setMusicista(Musicista musicista) {
this.musicista = musicista;
}
}
BandHasMusicistaPK.java
package it.entities;
import java.io.Serializable;
import javax.persistence.*;
/**
* The primary key class for the band_has_musicista database table.
*
*/
@Embeddable
public class BandHasMusicistaPK implements Serializable {
//default serial version id, required for serializable classes.
private static final long serialVersionUID = 1L;
private Band band;
private Musicista musicista;
public BandHasMusicistaPK() {
}
@ManyToOne
// @JoinColumn(name="BAND_ID")
public Band getBand() {
return this.band;
}
public void setBand(Band band) {
this.band = band;
}
@ManyToOne
// @JoinColumn(name="MUSICISTA_ID")
public Musicista getMusicista() {
return this.musicista;
}
public void setMusicista(Musicista musicista) {
this.musicista = musicista;
}
}
Musicista.java
package it.entities;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.NamedQuery;
import javax.persistence.OneToMany;
import javax.persistence.OneToOne;
import javax.persistence.PrimaryKeyJoinColumn;
import javax.persistence.Table;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;
import org.hibernate.annotations.GenericGenerator;
import org.hibernate.annotations.Parameter;
/**
* The persistent class for the MUSICISTA database table.
*
*/
@Entity
@Table(name="MUSICISTA")
@NamedQuery(name="Musicista.findAll", query="SELECT m FROM Musicista m")
public class Musicista implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(generator="SharedPrimaryKeyGenerator")
@GenericGenerator(name="SharedPrimaryKeyGenerator", strategy="foreign", parameters = @Parameter(name="property", value="account"))
@Column(name = "ID", unique = true, nullable = false)
private int id;
@Column(name="COGNOME", nullable=false, length=155)
private String cognome;
@Temporal(TemporalType.DATE)
@Column(name="DATA_NASCITA")
private Date dataNascita;
@Column(name="NOME", nullable=false, length=155)
private String nome;
//bi-directional one-to-one association to Account
@OneToOne
@PrimaryKeyJoinColumn
private Account account;
@OneToMany(mappedBy="pk.musicista", fetch = FetchType.LAZY, cascade={CascadeType.ALL})
private List<BandHasMusicista> bandHasMusicista = new ArrayList<BandHasMusicista>();
public Musicista() {
}
public int getId() {
return this.id;
}
public void setId(int id) {
this.id = id;
}
public String getCognome() {
return this.cognome;
}
public void setCognome(String cognome) {
this.cognome = cognome;
}
public Date getDataNascita() {
return this.dataNascita;
}
public void setDataNascita(Date dataNascita) {
this.dataNascita = dataNascita;
}
public String getNome() {
return this.nome;
}
public void setNome(String nome) {
this.nome = nome;
}
public Account getAccount() {
return this.account;
}
public void setAccount(Account account) {
this.account = account;
}
// @OneToMany(fetch = FetchType.LAZY, mappedBy = "pk.musicista")
public List<BandHasMusicista> getBandHasMusicista() {
return bandHasMusicista;
}
public void setBandHasMusicista(List<BandHasMusicista> bandHasMusicista) {
this.bandHasMusicista = bandHasMusicista;
}
}
BandLogic.java
package it.logic;
import it.entities.Band;
import it.entities.BandHasMusicista;
import it.entities.Citta;
import it.entities.Musicista;
import it.interfaces.ServiceBean;
import it.invo.AddBandInVO;
import javax.persistence.EntityManager;
public class BandLogic {
EntityManager em = null;
/**
* Default constructor.
*/
public BandLogic() {
em = ServiceBean.getEm();
}
public boolean addBand(AddBandInVO inVO) {
System.out.println("IN - addBand() INPUT = " + inVO);
Musicista musicista = em.find(Musicista.class, inVO.getAccountId());
Citta citta = em.find(Citta.class, inVO.getCitta());
if(musicista != null){
Band band = new Band();
band.setNome(inVO.getNome());
band.setDescrizione(inVO.getDescrizione());
band.setCitta(citta);
BandHasMusicista bandHasMusicista = new BandHasMusicista();
bandHasMusicista.setBand(band);
bandHasMusicista.setMusicista(musicista);
bandHasMusicista.setBandAccept(true);
bandHasMusicista.setMusicistaAccept(true);
band.getBandHasMusicista().add(bandHasMusicista);
em.persist(band);
em.flush();
em.clear();
}else{
System.out.println("Account is not Musicista");
return false;
}
System.out.println("OUT - addBand()");
return true;
}
}
堆栈跟踪：
javax.persistence.PersistenceException: org.hibernate.exception.ConstraintViolationException: Could not execute JDBC batch update
at org.hibernate.ejb.AbstractEntityManagerImpl.throwPersistenceException(AbstractEntityManagerImpl.java:614)
at org.hibernate.ejb.AbstractEntityManagerImpl.flush(AbstractEntityManagerImpl.java:307)
at it.logic.BandLogic.addBand(BandLogic.java:46)
at it.interfaces.ServiceBean.addBand(ServiceBean.java:184)
at it.test.BandTest.testAddBand(BandTest.java:25)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at junit.framework.TestCase.runTest(TestCase.java:176)
at junit.framework.TestCase.runBare(TestCase.java:141)
at junit.framework.TestResult$1.protect(TestResult.java:122)
at junit.framework.TestResult.runProtected(TestResult.java:142)
at junit.framework.TestResult.run(TestResult.java:125)
at junit.framework.TestCase.run(TestCase.java:129)
at junit.framework.TestSuite.runTest(TestSuite.java:255)
at junit.framework.TestSuite.run(TestSuite.java:250)
at org.junit.internal.runners.JUnit38ClassRunner.run(JUnit38ClassRunner.java:84)
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 execute JDBC batch update
at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:94)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66)
at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:275)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:266)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:167)
at org.hibernate.event.def.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:321)
at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:50)
at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1027)
at org.hibernate.ejb.AbstractEntityManagerImpl.flush(AbstractEntityManagerImpl.java:304)
... 22 more
Caused by: java.sql.BatchUpdateException: Column 'BAND_ID' cannot be null
at com.mysql.jdbc.PreparedStatement.executeBatchSerially(PreparedStatement.java:2054)
at com.mysql.jdbc.PreparedStatement.executeBatch(PreparedStatement.java:1467)
at org.hibernate.jdbc.BatchingBatcher.doExecuteBatch(BatchingBatcher.java:70)
at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:268)
... 28 more
Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Column 'BAND_ID' cannot be null
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.Util.getInstance(Util.java:386)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1041)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4187)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4119)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2570)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2731)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2815)
at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2155)
at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2458)
at com.mysql.jdbc.PreparedStatement.executeBatchSerially(PreparedStatement.java:2006)
... 31 more