Hello!

If I try to run the program under JDK 7 final, I get the following exception when switching to screens:

Exception in thread "AWT-EventQueue-0" java.lang.IllegalStateException: This function should be called while holding treeLock
        at java.awt.Component.checkTreeLock(Component.java:1195)
        at java.awt.Container.validateTree(Container.java:1682)
        at vgrazi.concurrent.samples.examples.ConcurrentExample.initializeFrame(ConcurrentExample.java:383)
        at vgrazi.concurrent.samples.examples.ConcurrentExample.launchExample(ConcurrentExample.java:365)
        at vgrazi.concurrent.samples.launcher.ConcurrentExampleLauncher.launchExamplePanel(ConcurrentExampleLauncher.java:177)
        at vgrazi.concurrent.samples.examples.ExampleActionListener.actionPerformed(ExampleActionListener.java:21)
        at java.awt.MenuItem.processActionEvent(MenuItem.java:646)
        at java.awt.MenuItem.processEvent(MenuItem.java:605)
        at java.awt.MenuComponent.dispatchEventImpl(MenuComponent.java:349)
        at java.awt.MenuComponent.dispatchEvent(MenuComponent.java:337)
        at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:710)
        at java.awt.EventQueue.access$000(EventQueue.java:101)
        at java.awt.EventQueue$3.run(EventQueue.java:666)
        at java.awt.EventQueue$3.run(EventQueue.java:664)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
        at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:87)
        at java.awt.EventQueue$4.run(EventQueue.java:680)
        at java.awt.EventQueue$4.run(EventQueue.java:678)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:677)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:211)
        at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:128)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:117)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:113)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:105)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:90)