Bug 126658 [CommonNavigator] [DND] Complete definition of DND API
tests/org.eclipse.ui.tests.navigator/src/org/eclipse/ui/tests/navigator/extension/TestContentProvider.java
TestExtensionTreeData data = (TestExtensionTreeData) element;
			return data.getChildren().length > 0;
		}
		return false;
	}
	public Object[] getElements(Object inputElement) {
		return getChildren(inputElement);
	}
	public void dispose() {
		rootElements.clear();
		ResourcesPlugin.getWorkspace().removeResourceChangeListener(this);
	}
	public void inputChanged(Viewer aViewer, Object oldInput, Object newInput) {
		if (oldInput != null && !oldInput.equals(newInput))
			rootElements.clear();
		viewer = (StructuredViewer)aViewer;
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.core.resources.IResourceChangeListener#resourceChanged(org.eclipse.core.resources.IResourceChangeEvent)
	 */
	public void resourceChanged(IResourceChangeEvent event) {
		IResourceDelta delta = event.getDelta();
		try {
			delta.accept(this);
		} catch (CoreException e) { 
			e.printStackTrace();
		}
	}