JPA：deleteAllエントリと1つのトランザクションで1つのエントリを再作成

Question

問題があり、1つのテーブルからすべてのエントリを削除し、削除したものと同じIDを持つ単一のアイテムを最初から作成したい。これは、テーブルが空ではないように、1つのトランザクション内になければなりません。

ヒント：Springバッチを使用してチャンクリスナーbeforeChunk（トランザクション内にある）によってタルベを削除すると、リーダー/ライターが後で実行されてデータの新しいバージョンを保持します。

Currentely、私は、私はこのエラーを受け取ることを行う場合：

Encountered an error executing step importXXXXX in job jobXXXX java.lang.IllegalArgumentException: Cannot merge an Entity that has been removed

スタックトレース：

at org.eclipse.persistence.internal.sessions.MergeManager.registerObjectForMergeCloneIntoWorkingCopy(MergeManager.java:1070) ~[eclipselink-2.6.4.jar:2.6.4.v20160829-44060b6] 
at org.eclipse.persistence.internal.sessions.MergeManager.mergeChangesOfCloneIntoWorkingCopy(MergeManager.java:564) ~[eclipselink-2.6.4.jar:2.6.4.v20160829-44060b6] 
at org.eclipse.persistence.internal.sessions.MergeManager.mergeChanges(MergeManager.java:313) ~[eclipselink-2.6.4.jar:2.6.4.v20160829-44060b6] 
at org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.mergeCloneWithReferences(UnitOfWorkImpl.java:3521) ~[eclipselink-2.6.4.jar:2.6.4.v20160829-44060b6] 
at org.eclipse.persistence.internal.sessions.RepeatableWriteUnitOfWork.mergeCloneWithReferences(RepeatableWriteUnitOfWork.java:387) ~[eclipselink-2.6.4.jar:2.6.4.v20160829-44060b6] 
at org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.mergeCloneWithReferences(UnitOfWorkImpl.java:3481) ~[eclipselink-2.6.4.jar:2.6.4.v20160829-44060b6] 
at org.eclipse.persistence.internal.jpa.EntityManagerImpl.mergeInternal(EntityManagerImpl.java:553) ~[eclipselink-2.6.4.jar:2.6.4.v20160829-44060b6] 
at org.eclipse.persistence.internal.jpa.EntityManagerImpl.merge(EntityManagerImpl.java:530) ~[eclipselink-2.6.4.jar:2.6.4.v20160829-44060b6] 
at org.springframework.batch.item.database.JpaItemWriter.doWrite(JpaItemWriter.java:104) ~[spring-batch-infrastructure-3.0.7.RELEASE.jar:3.0.7.RELEASE] 
at org.springframework.batch.item.database.JpaItemWriter.write(JpaItemWriter.java:83) ~[spring-batch-infrastructure-3.0.7.RELEASE.jar:3.0.7.RELEASE] 
at org.springframework.batch.core.step.item.SimpleChunkProcessor.writeItems(SimpleChunkProcessor.java:175) ~[spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE] 
at org.springframework.batch.core.step.item.SimpleChunkProcessor.doWrite(SimpleChunkProcessor.java:151) ~[spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE] 
at org.springframework.batch.core.step.item.SimpleChunkProcessor.write(SimpleChunkProcessor.java:274) ~[spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE] 
at org.springframework.batch.core.step.item.SimpleChunkProcessor.process(SimpleChunkProcessor.java:199) ~[spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE] 
at org.springframework.batch.core.step.item.ChunkOrientedTasklet.execute(ChunkOrientedTasklet.java:75) ~[spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE] 
at org.springframework.batch.core.step.tasklet.TaskletStep$ChunkTransactionCallback.doInTransaction(TaskletStep.java:406) ~[spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE] 
at org.springframework.batch.core.step.tasklet.TaskletStep$ChunkTransactionCallback.doInTransaction(TaskletStep.java:330) ~[spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE] 
at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:133) ~[spring-tx-4.3.7.RELEASE.jar:4.3.7.RELEASE] 
at org.springframework.batch.core.step.tasklet.TaskletStep$2.doInChunkContext(TaskletStep.java:271) ~[spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE] 
at org.springframework.batch.core.scope.context.StepContextRepeatCallback.doInIteration(StepContextRepeatCallback.java:81) ~[spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE] 
at org.springframework.batch.repeat.support.RepeatTemplate.getNextResult(RepeatTemplate.java:374) ~[spring-batch-infrastructure-3.0.7.RELEASE.jar:3.0.7.RELEASE] 
at org.springframework.batch.repeat.support.RepeatTemplate.executeInternal(RepeatTemplate.java:215) ~[spring-batch-infrastructure-3.0.7.RELEASE.jar:3.0.7.RELEASE] 
at org.springframework.batch.repeat.support.RepeatTemplate.iterate(RepeatTemplate.java:144) ~[spring-batch-infrastructure-3.0.7.RELEASE.jar:3.0.7.RELEASE] 
at org.springframework.batch.core.step.tasklet.TaskletStep.doExecute(TaskletStep.java:257) ~[spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE] 
at org.springframework.batch.core.step.AbstractStep.execute(AbstractStep.java:200) [spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE] 
at org.springframework.batch.core.job.SimpleStepHandler.handleStep(SimpleStepHandler.java:148) [spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE] 
at org.springframework.batch.core.job.flow.JobFlowExecutor.executeStep(JobFlowExecutor.java:64) [spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE] 
at org.springframework.batch.core.job.flow.support.state.StepState.handle(StepState.java:67) [spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE] 
at org.springframework.batch.core.job.flow.support.SimpleFlow.resume(SimpleFlow.java:169) [spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE] 
at org.springframework.batch.core.job.flow.support.SimpleFlow.start(SimpleFlow.java:144) [spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE] 
at org.springframework.batch.core.job.flow.FlowJob.doExecute(FlowJob.java:134) [spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE] 
at org.springframework.batch.core.job.AbstractJob.execute(AbstractJob.java:306) [spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE] 
at org.springframework.batch.core.launch.support.SimpleJobLauncher$1.run(SimpleJobLauncher.java:135) [spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE] 
at org.springframework.core.task.SyncTaskExecutor.execute(SyncTaskExecutor.java:50) [spring-core-4.3.7.RELEASE.jar:4.3.7.RELEASE] 
at org.springframework.batch.core.launch.support.SimpleJobLauncher.run(SimpleJobLauncher.java:128) [spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE] 

それはすでに削除されているが、あなたがエントリをpersitする考えを持っていますかこの取引。

ありがとうございます！

Answer 1

specificationはセクションに言って、次の持つ独立したエンティティの状態をマージ3.2.4.1：

If X is a removed entity instance, an IllegalArgumentException will be thrown by the merge operation (or the transaction commit will fail).

また、セクションで述べている3.2.1エンティティインスタンスを永続化：

If X is a removed entity, it becomes managed.

さらにセクション3.2.3データベースとの同期：

If X is a managed entity, it is synchronized to the database.

[...]

• If X is a removed entity, it is removed from the database. No cascade options are relevant.

したがって、JPAで何をしようとしているかはわかりません。私のコメントで示唆されているように、エンティティの再利用があります。