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某些背景;我正在運行一個Vaadin 7應用程序作爲Liferay 6.2.GA6上使用DeltaManager在羣集Tomcat7實例上運行的portlet。如何在Vaadin請求中設置Liferay的APPLICATION_SCOPE中的屬性
我試圖在我的Vaadin應用程序中設置一個用戶級會話屬性，其他portlet可以查看並做出適當的反應。
下面的代碼導致線程死鎖。
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PortletSession session = ((WrappedPortletSession)UI.getCurrent().getSesion()).getPortletSession();
session.setAttribute("CURRENT_NOTIFICATION",notificationDTO,PortletSession.APPLICATION_SCOPE);
我得到的縮寫線程轉儲...
"http-nio-8081-exec-80" - Thread [email protected]
java.lang.Thread.State: WAITING
at sun.misc.Unsafe.park(Native Method)
- waiting to lock <7c3f1e38> (a java.util.concurrent.locks.ReentrantReadWriteLock$NonfairSync) owned by "http-nio-8081-exec-82" [email protected]
at java.util.concurrent.locks.LockSupport.park(LockSupport.java:186)
at java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:834)
at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireQueued(AbstractQueuedSynchronizer.java:867)
at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquire(AbstractQueuedSynchronizer.java:1197)
at java.util.concurrent.locks.ReentrantReadWriteLock$WriteLock.lock(ReentrantReadWriteLock.java:945)
at org.apache.catalina.ha.session.DeltaSession.lock(DeltaSession.java:199)
at org.apache.catalina.ha.session.DeltaSession.setAttribute(DeltaSession.java:726)
at org.apache.catalina.ha.session.DeltaSession.setAttribute(DeltaSession.java:711)
at org.apache.catalina.session.StandardSessionFacade.setAttribute(StandardSessionFacade.java:154)
at com.liferay.portlet.PortletSessionImpl.setAttribute(PortletSessionImpl.java:188)
at mypackage.com.view.NotificationEntryView.enter(NotificationEntryView.java:181)
"http-nio-8081-exec-82" - Thread [email protected]
java.lang.Thread.State: WAITING
at sun.misc.Unsafe.park(Native Method)
- waiting to lock <fa6510c> (a java.util.concurrent.locks.ReentrantLock$NonfairSync) owned by "http-nio-8081-exec-80" [email protected]
at java.util.concurrent.locks.LockSupport.park(LockSupport.java:186)
at java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:834)
at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireQueued(AbstractQueuedSynchronizer.java:867)
at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquire(AbstractQueuedSynchronizer.java:1197)
at java.util.concurrent.locks.ReentrantLock$NonfairSync.lock(ReentrantLock.java:214)
at java.util.concurrent.locks.ReentrantLock.lock(ReentrantLock.java:290)
at com.vaadin.server.VaadinSession.writeObject(VaadinSession.java:1432)
at sun.reflect.GeneratedMethodAccessor1827.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:988)
at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1495)
at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1431)
at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1177)
at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:347)
at org.apache.catalina.ha.session.DeltaRequest$AttributeInfo.writeExternal(DeltaRequest.java:407)
at org.apache.catalina.ha.session.DeltaRequest.writeExternal(DeltaRequest.java:300)
at org.apache.catalina.ha.session.DeltaRequest.serialize(DeltaRequest.java:314)
at org.apache.catalina.ha.session.DeltaManager.serializeDeltaRequest(DeltaManager.java:610)
at org.apache.catalina.ha.session.DeltaManager.requestCompleted(DeltaManager.java:996)
- locked <5603aa01> (a org.apache.catalina.ha.session.DeltaRequest)
看來，在PorletSession的的setAttribute調用觸發DeltaSession嘗試在會話這Vaadin的鎖已經（一種-的）持有這會造成死鎖。
Vaadin建議使用VaadinSession或UI.access（）。這並沒有幫助。
我的下一個想法是手動解鎖VaadinSession，設置屬性，然後重新鎖定VaadinSession，這似乎是一個冒險的舉動。
任何人都可以推薦一個解決方案嗎？