/*
  * (non-Javadoc)
  *
  * @see org.eclipse.ui.plugin.AbstractUIPlugin#start(org.osgi.framework.BundleContext)
  */
 public void start(BundleContext context) throws Exception {
   super.start(context);
   plugin = this;
   viewpoints = new HashSet<Viewpoint>();
   viewpoints.addAll(
       ViewpointRegistry.getInstance()
           .registerFromPlugin(PLUGIN_ID + "/description/togaf.extension.odesign"));
 }
 /*
  * (non-Javadoc)
  *
  * @see org.eclipse.ui.plugin.AbstractUIPlugin#stop(org.osgi.framework.BundleContext)
  */
 public void stop(BundleContext context) throws Exception {
   plugin = null;
   if (viewpoints != null) {
     for (final Viewpoint viewpoint : viewpoints) {
       ViewpointRegistry.getInstance().disposeFromPlugin(viewpoint);
     }
     viewpoints.clear();
     viewpoints = null;
   }
   super.stop(context);
 }