// opened events instead of property change events would be a better
// solution. Either way, more probably needs to be done to clean up
// data model objects when a case is closed.
if (oldValue != null && newValue == null) {
// The current case has been closed. Reset the ExplorerManager.
Node emptyNode = new AbstractNode(Children.LEAF);
em.setRootContext(emptyNode);
} else if (newValue != null) {
// A new case has been opened. Reset the forward and back
// buttons. Note that a call to CoreComponentControl.openCoreWindows()
// by the new Case object will lead to a componentOpened() call