I have created C++ FFT sample project, open one of it's files, the opened Tools->Options->Editor clicked somewhere. Then
tried to quickly open several files not waiting when each of them is finished to be opened.
=> i've got an exception, but can not report it from IDE, because it is hang.

Exception is:
SEVERE [org.openide.util.RequestProcessor]: Error in RequestProcessor org.openide.text.CloneableEditor$DoInitialize
java.lang.IllegalStateException
        at org.openide.text.CloneableEditorSupport.prepareDocument(CloneableEditorSupport.java:595)
        at org.openide.text.CloneableEditor$DoInitialize.initNonVisual(CloneableEditor.java:377)
        at org.openide.text.CloneableEditor$DoInitialize.run(CloneableEditor.java:320)
        at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:602)
        at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:1084)
Caused: org.openide.util.RequestProcessor$SlowItem: task failed due to
        at org.openide.util.RequestProcessor$Task.schedule(RequestProcessor.java:655)
        at org.openide.text.CloneableEditor$DoInitialize.<init>(CloneableEditor.java:287)
        at org.openide.text.CloneableEditor.initialize(CloneableEditor.java:222)
        at org.openide.text.CloneableEditor.componentShowing(CloneableEditor.java:198)
        at org.openide.windows.WindowManager.componentShowing(WindowManager.java:332)
        at org.netbeans.core.windows.WindowManagerImpl.componentShowing(WindowManagerImpl.java:1022)
        at org.netbeans.core.windows.view.DefaultView.changeGUI(DefaultView.java:161)
        at org.netbeans.core.windows.ViewRequestor.dispatchRequest(ViewRequestor.java:269)
        at org.netbeans.core.windows.ViewRequestor.processRequest(ViewRequestor.java:245)
        at org.netbeans.core.windows.ViewRequestor.postRequest(ViewRequestor.java:183)
        at org.netbeans.core.windows.ViewRequestor.scheduleRequest(ViewRequestor.java:123)
        at org.netbeans.core.windows.Central.activateModeTopComponent(Central.java:1760)
        at org.netbeans.core.windows.WindowManagerImpl.topComponentRequestActive(WindowManagerImpl.java:1145)
        at org.openide.windows.TopComponent.requestActive(TopComponent.java:789)
        at org.openide.windows.CloneableOpenSupport$1.run(CloneableOpenSupport.java:99)
        at org.openide.util.Mutex.doEvent(Mutex.java:1335)
        at org.openide.util.Mutex.writeAccess(Mutex.java:452)
        at org.openide.windows.CloneableOpenSupport.open(CloneableOpenSupport.java:95)
        at org.openide.text.CloneableEditorSupport.open(CloneableEditorSupport.java:463)
        at org.openide.awt.ActionDefaultPerfomer.actionPerformed(ActionDefaultPerfomer.java:67)
        at org.openide.awt.ContextAction$Performer.actionPerformed(ContextAction.java:223)
        at org.openide.awt.ContextManager.actionPerformed(ContextManager.java:241)
        at org.openide.awt.ContextAction.actionPerformed(ContextAction.java:106)
        at org.netbeans.modules.openide.util.ActionsBridge$ActionRunnable$1.run(ActionsBridge.java:108)
        at org.netbeans.modules.openide.util.ActionsBridge.implPerformAction(ActionsBridge.java:83)
        at org.netbeans.modules.openide.util.ActionsBridge.doPerformAction(ActionsBridge.java:67)
        at org.openide.awt.GeneralAction$DelegateAction.actionPerformed(GeneralAction.java:218)
        at org.openide.explorer.view.TreeView$PopupSupport.mouseClicked(TreeView.java:1544)
        at java.awt.AWTEventMulticaster.mouseClicked(AWTEventMulticaster.java:253)
        at java.awt.AWTEventMulticaster.mouseClicked(AWTEventMulticaster.java:252)
        at java.awt.AWTEventMulticaster.mouseClicked(AWTEventMulticaster.java:252)
        at java.awt.AWTEventMulticaster.mouseClicked(AWTEventMulticaster.java:252)
        at java.awt.Component.processMouseEvent(Component.java:6266)
        at javax.swing.JComponent.processMouseEvent(JComponent.java:3267)
        at java.awt.Component.processEvent(Component.java:6028)
        at java.awt.Container.processEvent(Container.java:2041)
        at java.awt.Component.dispatchEventImpl(Component.java:4630)
        at java.awt.Container.dispatchEventImpl(Container.java:2099)
        at java.awt.Component.dispatchEvent(Component.java:4460)
        at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4574)
        at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4247)
        at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4168)
        at java.awt.Container.dispatchEventImpl(Container.java:2085)
        at java.awt.Window.dispatchEventImpl(Window.java:2475)
        at java.awt.Component.dispatchEvent(Component.java:4460)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)
        at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:125)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
        at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
[catch] at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)