Java 修改注释以避免“唯一约束或索引冲突”错误？

我正试图绕过hibernate，但我遇到了一点障碍。当我尝试将代码插入我的

hsqldb

基本设置是有一个

歌曲

，

播放列表

表格。播放列表应该只是映射到它们包含的歌曲ID。所以，我的课程设置如下

播放列表类 客户端代码 我认为这是因为我对映射的理解很差。有人能帮我澄清一下吗

@OneToMany（fetch=FetchType.EAGER）@Cascade（CascadeType.ALL）
私人列表歌曲；

---

我认为问题就在这里。你有歌曲数据库，对吗？用户可以创建播放列表并用任意一组歌曲填充它们。因此，您需要

@manytomy

而不需要级联。

为什么列表中不同歌曲的歌曲id相同？有什么理由吗？

@Entity
public class MyPlaylist {
    @Id @GeneratedValue
    private int id;
    private String name;
    @ElementCollection
    @OneToMany(fetch=FetchType.EAGER) @Cascade(CascadeType.ALL) 
    private List<Song> songs;

@Entity
public class Song {
    @Id @GeneratedValue(strategy=GenerationType.AUTO)
    private int id;
    private String title;
    private String artist; 
    private String album; 
    private String filePath; 
    private String trackLength;

// Along the lines of...
List<Song> playlistSongs = loadSongs();
Playlist p = new Playlist("MyPLaylist", playlistSongs);
SessionFactory factory = new Configuration().configure().buildSessionFactory();
Session s = factory.openSession();
s.beginTransaction();
s.saveOrUpdate(p);
s.close();

Exception in thread "AWT-EventQueue-0" org.hibernate.exception.ConstraintViolationException: could not execute statement
    at org.hibernate.exception.internal.SQLExceptionTypeDelegate.convert(SQLExceptionTypeDelegate.java:74)
    at org.hibernate.exception.internal.StandardSQLExceptionConverter.convert(StandardSQLExceptionConverter.java:49)
    at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:125)
    at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:110)
    at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.executeUpdate(ResultSetReturnImpl.java:136)
    at org.hibernate.engine.jdbc.batch.internal.NonBatchingBatch.addToBatch(NonBatchingBatch.java:58)
    at org.hibernate.persister.collection.AbstractCollectionPersister.recreate(AbstractCollectionPersister.java:1256)
    at org.hibernate.action.internal.CollectionRecreateAction.execute(CollectionRecreateAction.java:58)
    at org.hibernate.engine.spi.ActionQueue.execute(ActionQueue.java:393)
    at org.hibernate.engine.spi.ActionQueue.executeActions(ActionQueue.java:385)
    at org.hibernate.engine.spi.ActionQueue.executeActions(ActionQueue.java:307)
    at org.hibernate.event.internal.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:339)
    at org.hibernate.event.internal.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:52)
    at org.hibernate.internal.SessionImpl.flush(SessionImpl.java:1240)
    at org.hibernate.internal.SessionImpl.managedFlush(SessionImpl.java:404)
    at org.hibernate.engine.transaction.internal.jdbc.JdbcTransaction.beforeTransactionCommit(JdbcTransaction.java:101)
    at org.hibernate.engine.transaction.spi.AbstractTransactionImpl.commit(AbstractTransactionImpl.java:175)
    at com.titanplayer.persistence.Database.save(Database.java:35)
    at com.titanplayer.gui.PlayerGUI.newPlaylistButtonActionPerformed(PlayerGUI.java:441)
    at com.titanplayer.gui.PlayerGUI.access$2200(PlayerGUI.java:47)
    at com.titanplayer.gui.PlayerGUI$8.actionPerformed(PlayerGUI.java:321)
    at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2018)
    at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2341)
    at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
    at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259)
    at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:252)
    at java.awt.Component.processMouseEvent(Component.java:6505)
    at javax.swing.JComponent.processMouseEvent(JComponent.java:3321)
    at java.awt.Component.processEvent(Component.java:6270)
    at java.awt.Container.processEvent(Container.java:2229)
    at java.awt.Component.dispatchEventImpl(Component.java:4861)
    at java.awt.Container.dispatchEventImpl(Container.java:2287)
    at java.awt.Component.dispatchEvent(Component.java:4687)
    at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4832)
    at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4492)
    at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4422)
    at java.awt.Container.dispatchEventImpl(Container.java:2273)
    at java.awt.Window.dispatchEventImpl(Window.java:2719)
    at java.awt.Component.dispatchEvent(Component.java:4687)
    at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:729)
    at java.awt.EventQueue.access$200(EventQueue.java:103)
    at java.awt.EventQueue$3.run(EventQueue.java:688)
    at java.awt.EventQueue$3.run(EventQueue.java:686)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:87)
    at java.awt.EventQueue$4.run(EventQueue.java:702)
    at java.awt.EventQueue$4.run(EventQueue.java:700)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
    at java.awt.EventQueue.dispatchEvent(EventQueue.java:699)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:242)
    at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:161)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:150)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:146)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:138)
    at java.awt.EventDispatchThread.run(EventDispatchThread.java:91)
Caused by: java.sql.SQLIntegrityConstraintViolationException: integrity constraint violation: unique constraint or index violation; UK_Q3MYU734MY659N16AROSDTO8P table: PLAYLIST_SONG
    at org.hsqldb.jdbc.JDBCUtil.sqlException(Unknown Source)
    at org.hsqldb.jdbc.JDBCUtil.sqlException(Unknown Source)
    at org.hsqldb.jdbc.JDBCPreparedStatement.fetchResult(Unknown Source)
    at org.hsqldb.jdbc.JDBCPreparedStatement.executeUpdate(Unknown Source)
    at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.executeUpdate(ResultSetReturnImpl.java:133)

@OneToMany(fetch=FetchType.EAGER) @Cascade(CascadeType.ALL) 
private List<Song> songs;