13

我所有的课都有一个

@版本

注释，所以我假设他们正在使用乐观锁定。

但是我的日志中出现了以下异常，这似乎表明我使用了悲观锁定。那么它是哪一个？（我想用乐观锁）

update Song set acoustidFingerprint=?, acoustidId=?, album=?, albumArtist=?, albumArtistSort=?, albumSort=?, amazonId=?, arranger=?, artist=?, artistSort=?, artists=?, barcode=?, bpm=?, catalogNo=?, comment=?, composer=?, composerSort=?, conductor=?, country=?, custom1=?, custom2=?, custom3=?, custom4=?, custom5=?, discNo=?, discSubtitle=?, discTotal=?, djmixer=?, duration=?, encoder=?, engineer=?, fbpm=?, filename=?, genre=?, grouping=?, isCompilation=?, isrc=?, keyOfSong=?, language=?, lastModified=?, lyricist=?, lyrics=?, media=?, mixer=?, mood=?, musicbrainzArtistId=?, musicbrainzDiscId=?, musicbrainzOriginalReleaseId=?, musicbrainzRecordingId=?, musicbrainzReleaseArtistId=?, musicbrainzReleaseCountry=?, musicbrainzReleaseGroupId=?, musicbrainzReleaseId=?, musicbrainzReleaseStatus=?, musicbrainzReleaseType=?, musicbrainzWorkId=?, musicipId=?, occasion=?, originalAlbum=?, originalArtist=?, originalLyricist=?, originalYear=?, producer=?, quality=?, rating=?, recordLabel=?, releaseYear=?, remixer=?, script=?, subtitle=?, tags=?, tempo=?, title=?, titleSort=?, track=?, trackTotal=?, urlDiscogsArtistSite=?, urlDiscogsReleaseSite=?, urlLyricsSite=?, urlOfficialArtistSite=?, urlOfficialReleaseSite=?, urlWikipediaArtistSite=?, urlWikipediaReleaseSite=?, version=? where recNo=? and version=? [50200-172]
**org.hibernate.PessimisticLockException: Timeout trying to lock table ; SQL statement:**
update Song set acoustidFingerprint=?, acoustidId=?, album=?, albumArtist=?, albumArtistSort=?, albumSort=?, amazonId=?, arranger=?, artist=?, artistSort=?, artists=?, barcode=?, bpm=?, catalogNo=?, comment=?, composer=?, composerSort=?, conductor=?, country=?, custom1=?, custom2=?, custom3=?, custom4=?, custom5=?, discNo=?, discSubtitle=?, discTotal=?, djmixer=?, duration=?, encoder=?, engineer=?, fbpm=?, filename=?, genre=?, grouping=?, isCompilation=?, isrc=?, keyOfSong=?, language=?, lastModified=?, lyricist=?, lyrics=?, media=?, mixer=?, mood=?, musicbrainzArtistId=?, musicbrainzDiscId=?, musicbrainzOriginalReleaseId=?, musicbrainzRecordingId=?, musicbrainzReleaseArtistId=?, musicbrainzReleaseCountry=?, musicbrainzReleaseGroupId=?, musicbrainzReleaseId=?, musicbrainzReleaseStatus=?, musicbrainzReleaseType=?, musicbrainzWorkId=?, musicipId=?, occasion=?, originalAlbum=?, originalArtist=?, originalLyricist=?, originalYear=?, producer=?, quality=?, rating=?, recordLabel=?, releaseYear=?, remixer=?, script=?, subtitle=?, tags=?, tempo=?, title=?, titleSort=?, track=?, trackTotal=?, urlDiscogsArtistSite=?, urlDiscogsReleaseSite=?, urlLyricsSite=?, urlOfficialArtistSite=?, urlOfficialReleaseSite=?, urlWikipediaArtistSite=?, urlWikipediaReleaseSite=?, version=? where recNo=? and version=? [50200-172]
    at org.hibernate.dialect.H2Dialect$2.convert(H2Dialect.java:317)
    at org.hibernate.exception.internal.StandardSQLExceptionConverter.convert(StandardSQLExceptionConverter.java:49)
    at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:125)
    at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:110)
    at org.hibernate.engine.jdbc.internal.proxy.AbstractStatementProxyHandler.continueInvocation(AbstractStatementProxyHandler.java:129)
    at org.hibernate.engine.jdbc.internal.proxy.AbstractProxyHandler.invoke(AbstractProxyHandler.java:81)
    at com.sun.proxy.$Proxy22.executeUpdate(Unknown Source)
    at org.hibernate.persister.entity.AbstractEntityPersister.update(AbstractEntityPersister.java:3123)
    at org.hibernate.persister.entity.AbstractEntityPersister.updateOrInsert(AbstractEntityPersister.java:3021)
    at org.hibernate.persister.entity.AbstractEntityPersister.update(AbstractEntityPersister.java:3350)
    at org.hibernate.action.internal.EntityUpdateAction.execute(EntityUpdateAction.java:140)
    at org.hibernate.engine.spi.ActionQueue.execute(ActionQueue.java:362)
    at org.hibernate.engine.spi.ActionQueue.executeActions(ActionQueue.java:354)
    at org.hibernate.engine.spi.ActionQueue.executeActions(ActionQueue.java:276)
    at org.hibernate.event.internal.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:326)
    at org.hibernate.event.internal.DefaultAutoFlushEventListener.onAutoFlush(DefaultAutoFlushEventListener.java:62)
    at org.hibernate.internal.SessionImpl.autoFlushIfRequired(SessionImpl.java:1182)
    at org.hibernate.internal.SessionImpl.list(SessionImpl.java:1611)
    at org.hibernate.internal.CriteriaImpl.list(CriteriaImpl.java:374)
    at com.jthink.songkong.db.SongCache.loadSongsFromDatabase(SongCache.java:58)
    at com.jthink.songkong.analyse.analyser.SongGroup.getSongs(SongGroup.java:48)
    at com.jthink.songkong.analyse.analyser.MergeMusicBrainzMatches.matchToMissingTracks(MergeMusicBrainzMatches.java:318)
    at com.jthink.songkong.analyse.analyser.MergeMusicBrainzMatches.call(MergeMusicBrainzMatches.java:105)
    at com.jthink.songkong.analyse.analyser.MergeMusicBrainzMatches.call(MergeMusicBrainzMatches.java:40)
    at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
    at java.util.concurrent.FutureTask.run(FutureTask.java:166)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at java.lang.Thread.run(Thread.java:722)
Caused by: org.h2.jdbc.JdbcSQLException: Timeout trying to lock table ; SQL statement:
update Song set acoustidFingerprint=?, acoustidId=?, album=?, albumArtist=?, albumArtistSort=?, albumSort=?, amazonId=?, arranger=?, artist=?, artistSort=?, artists=?, barcode=?, bpm=?, catalogNo=?, comment=?, composer=?, composerSort=?, conductor=?, country=?, custom1=?, custom2=?, custom3=?, custom4=?, custom5=?, discNo=?, discSubtitle=?, discTotal=?, djmixer=?, duration=?, encoder=?, engineer=?, fbpm=?, filename=?, genre=?, grouping=?, isCompilation=?, isrc=?, keyOfSong=?, language=?, lastModified=?, lyricist=?, lyrics=?, media=?, mixer=?, mood=?, musicbrainzArtistId=?, musicbrainzDiscId=?, musicbrainzOriginalReleaseId=?, musicbrainzRecordingId=?, musicbrainzReleaseArtistId=?, musicbrainzReleaseCountry=?, musicbrainzReleaseGroupId=?, musicbrainzReleaseId=?, musicbrainzReleaseStatus=?, musicbrainzReleaseType=?, musicbrainzWorkId=?, musicipId=?, occasion=?, originalAlbum=?, originalArtist=?, originalLyricist=?, originalYear=?, producer=?, quality=?, rating=?, recordLabel=?, releaseYear=?, remixer=?, script=?, subtitle=?, tags=?, tempo=?, title=?, titleSort=?, track=?, trackTotal=?, urlDiscogsArtistSite=?, urlDiscogsReleaseSite=?, urlLyricsSite=?, urlOfficialArtistSite=?, urlOfficialReleaseSite=?, urlWikipediaArtistSite=?, urlWikipediaReleaseSite=?, version=? where recNo=? and version=? [50200-172]
    at org.h2.message.DbException.getJdbcSQLException(DbException.java:329)
    at org.h2.message.DbException.get(DbException.java:158)
    at org.h2.command.Command.filterConcurrentUpdate(Command.java:281)
    at org.h2.command.Command.executeUpdate(Command.java:237)
    at org.h2.jdbc.JdbcPreparedStatement.executeUpdateInternal(JdbcPreparedStatement.java:154)
    at org.h2.jdbc.JdbcPreparedStatement.executeUpdate(JdbcPreparedStatement.java:140)
    at com.mchange.v2.c3p0.impl.NewProxyPreparedStatement.executeUpdate(NewProxyPreparedStatement.java:105)
    at sun.reflect.GeneratedMethodAccessor55.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:601)
    at org.hibernate.engine.jdbc.internal.proxy.AbstractStatementProxyHandler.continueInvocation(AbstractStatementProxyHandler.java:122)
    ... 24 more
4

3 回答 3

17

此异常是由于锁定超时。

引起：org.h2.jdbc.JdbcSQLException：超时试图锁定表；

在此处检查解决方案

hibernate 还提供了在应用程序中实现这两种类型的锁定的机制。

您的锁定策略可以是乐观的也可以是悲观的。

乐观的

乐观锁定假设多个事务可以在不相互影响的情况下完成，因此事务可以在不锁定它们影响的数据资源的情况下继续进行。在提交之前，每个事务都会验证没有其他事务修改过它的数据。如果检查显示有冲突的修改，提交事务将回滚[1]。

悲观

悲观锁定假设并发事务会相互冲突，并且要求资源在读取后锁定，只有在应用程序使用完数据后才解锁。

详细信息可以在这里找到

于 2013-09-12T08:34:58.727 回答
10

您正在使用乐观锁定，因为您的UPDATE声明已经表明：

where recNo=? and version=?

列的存在version就是乐观锁定的全部意义所在。

您被PessimisticLockException这可能是由显式或隐式行级锁引起的误导。

于 2016-07-05T14:26:20.240 回答
0

很可能，您将使用不同的数据库进行测试，而不是在 LIVE 环境中使用。

H2 会产生错误，这些错误可能不会出现在 Oracle、MySQL 等 LIVE 数据库上。意味着即使你的代码是正确的，但 H2 可能会乱七八糟。

MVCC=true 完美运行。同时，您应该确保针对您的用例在 LIVE 类系统上进行完整的集成测试，以验证 LIVE 数据库的行为。

于 2015-10-29T13:43:51.197 回答