作为多线程的JPA

Question

错误[ACTIVE]执行线程：队列“weblogic.kernel.default（自调优）”的“33”-07.02.2014 11:37:20,360 request_id=9E32EFA6-1374-4B1C-99E9-326A3A256B88错误代码：99异步任务中的错误，延迟0：

本地异常堆栈：Exception[EclipseLink-4002]（Eclipse Persistence Services-2.3.2.v20111125-r10461):org.Eclipse.Persistence.exceptions.databaseException内部异常：java.sql.sqlException：语句已经关闭错误代码：0调用：SELECT ID,FIRST_NAME,ISBLOCKED,LAST_NAME,MODIFIED,MSISDN,VERSION,OWNER_ID,CONTACT_ID FROM CONTACTS WHERE(OWNER_ID=？）bind=>[1 parameter bound]查询:ReadAllQuery(name=“vasserverfile://data/msgadmin/wls12c/wlserver_12.1/domains/vas-msg-tst-dmn/servers/vas-msg-tst-m1-man1-1/tmp/_wl_user/vasserver/c7nfil/war/web-inf/lib/_wl_cls_gen.jar_vasserverpu”referenceClass=contact sql=“select ID,FIRST_NAME,ISBLOCKED,LAST_NAME在org.eclipse.persistence.exceptions.databaseException.sqlException（databaseException.java:333)在org.eclipse.persistence.internal.databaseAccess.basicExecuteCall（databaseAccessor.java:644)在org.eclipse.persistence.internal.databaseAccess.databaseAccess.databaseAccess.executeCall（databaseAccess.java:535)在在org.eclipse.persistence.internal.queries.datasourceCallQueryMechanism.executeCall（datasourceCallQueryMechanism.java:207)在org.eclipse.persistence.internal.queries.datasourceCallQueryMechanism.java:193)在org.eclipse.persistence.internal.queries.datasourceCallQueryMechanism.executeCall（阿苏尔切卡尔克雷姆chanism.java:646)在org.eclipse.persistence.internal.queries.expressionQueryMechanism.selectAllRowsFromTable(expressionQueryMechanism.java:2611)在org.eclipse.persistence.internal.expressionQueryMechanism.java.expressionQueryMechanism.java:2570)在.java:1081)在org.eclipse.persistence.queries.databasequery.execute(databasequery.java:844)在org.eclipse.persistence.queries.objectLevelReadQuery.execute(objectLevelReadQuery.java:1040)在org.eclipse.persistence.queries.readAllQuery.execute(readAllQuery.java:392)

我正在尝试使用JPA多线程，但我采取了这种异常，任何想法来解决问题。

谢谢

Answer 1

EntityManager不是线程安全的，因此应该在单线程中使用EntityManager实例。在不同的线程中，您可以使用EntityManagerFactory实例，因为它是线程安全的。